The world is being slowly poisoned, the environment destroyed. Why don’t we care about such an apocalypse more? Clare Saxby joins us to discuss; Mary Beard considers the cultural legacy of Caligula, that most reviled of all emperors, via a revisionist work of fiction told from the perspective of the emperor's exiled sister; as Arsène Wenger's twenty-two year tenure as Arsenal manager draws to a close, the TLS's History editor and Arsenal fan David Horspool shares his thoughts on football's modern myth-making
Books
Mourning Nature: Hope at the heart of ecological loss and grief, edited by Ashlee and Karen Landman Cunsolo
Walking on Lava: Selected works for uncivilised times, edited by Charlotte Du Cann, Dougald Hine, Nick Hunt and Paul Kingsnorth
Energy Humanities: An anthology, edited by Imre Szeman and Dominic Boyer
Real-life millennial Samuel Earle pops in to consider the status of young people in an unequal society, keeping avocado references to a minimum; Ruth Scurr analyses the role of mothers in life and literature; and Madeline Miller talks about inhabiting the role of Circe.
Stefan Schmitz is a photographer living in Northern France and specializing in sensual and nude portraits.
I stumbled upon his work during one of my searches for photographers using Free Software on Flickr, and as someone who loves shooting portraits his work was an instant draw for me.
He’s a member of the forums here (@beachbum) and was gracious enough recently to spare some time chatting with me. Here is our conversation (edited for clarity)…
Are you shooting professionally?
Nope, I’m not a professional photographer, and I think I’m quite happy about that. I do happen to photograph my surroundings for ±40 years now, and I have a basic idea about camera-handling and light. Being a pro is about paying invoices by shooting photos, and I fear that the pressure at the end of some months or quarters can easily take the fun out of photography. I’m an engineer and photography is my second love behind wife and kids.
Every now and then some of my pictures are requested and published by some sort of magazine, press or web-service, and I appreciate the attention and exposure, but there is no (or very little) money in the kind of photography I specialize in, so … everything’s OK the way it is.
Starting with photographers: Andreas Feininger, Peter Lindbergh and Alfred Stieglitz. Check out the portrait of Georgia O’Keeffe by Alfred Stieglitz: it’s 100 years old and it’s all there. Pose, light, intensity, personality - nobody has invented anything [like it] afterwards. We all just try to get close. I feel the same when I look at images taken by Peter Lindbergh, but my eternal #1 is Andreas Feininger.
Georgia O’Keeffe by Alfred Stieglitz
I got the photo-virus from my father and I learned nearly everything from daddy’s well-worn copy of The Complete Photographer[amzn] (Feininger) from 1965. Every single photo in that book is a masterpiece, even the strictly “instructional” ones. You measure every photo-book in the world against this one and they all finish second. Get your copy!
How would you describe your own style overall?
I shoot portraits of women and most of the time they don’t wear clothes. The portrait-part is very important for me: the model must connect with the viewer and ideally the communication goes beyond skin-deep. I want to see (and show) more than just the surface, and when that happens, I just press the shutter-button and try to get out of the way of the model’s performance.
What motivates you when deciding what/how/who to shoot?
I like women, so I take photos of women. If I were interested in beetles, I’d buy a macro lens and shoot beetles. All kidding aside, I think it’s a natural thing to do. I am married to a beautiful woman, an ex-model, and when she got fed-up with my eternal “can we do one more shoot” requests, we discussed things and she allowed me to go ahead and shoot models. Her support is very important to me, but her taste is very different from mine.
I really never asked myself “why” I shoot sensual portraits and nudes. It just feels like “I want to do that” and I feel comfy with it. Does there have to be a reason?
The location is very important for me. Nothing is more boring than blinding a person with a flashlight in front of a gray wallpaper. A room, a window-sill, a landmark - there’s a lot of inspiration out there, and I often think “this is where I want to shoot”. Sometimes my wife tells me of some place she has been to or seen, and I check that out.
If you had to pick your own favorite 3 images of your work, which ones would you choose and why?
Jennifer is a very professional and inspiring model. We’ve worked together quite a number of times and while you may think that this shot was inspired by The Who’s “Pinball Wizard”, I’d answer “right band, wrong song”. It’s The Who, alright, but the song’s “A quick one while he’s away”.
I chose this photo because it’s all about Jennifer’s pose and facial expression. It’s sensual, even sexy, but looking at Jennifer’s face you forget about the naked skin and all. There’s beauty, there’s depth … that’s what I’m after.
This shot of Alice is an example for the importance of natural light. There are photographers out there who can arrange light in a similar way, but I doubt that Alice would express this natural serenity in a studio setup with cables and stands and electric-transformers humming.
She’s at ease, the light is perfect - I just try to be invisible because I don’t want to ruin the moment.
Try to escape Khiara’s eyes. Go, do it. It’s all there, the pose, the room, the ribbon-chair and the little icon, but those eyes make the picture. I did NOT whiten the eyeballs nor did I dodge the iris, and of course it’s all natural/available light.
If you had to pick 3 favorite images from someone else, which ones would you choose and why?
I already named Stieglitz’ Georgia O’Keeffe as an inspiration further up - next to that there’s Helmut Newton’s Big Nude III, Henrietta and Kim Basinger’s striptease in 9 1⁄2 weeks (white silk nighty and all). Each one a masterpiece, each one very influential for me. Imagine the truth and depth of Georgia with the force and pride of Henrietta and the erotic playfulness of Kim Basinger. That photo would rule the world.
Is there something outside of your comfort zone you wish you could try/shoot more of?
I would like to work more with women above the age of 35, but it’s hard to find them. In general they stop modeling nude when the kids arrive.
Shooting more often outdoors would be cool, too, but that’s not easy here in northern France - there is no guarantee for good weather, and it’s frustrating when you organize a shoot two weeks in advance just to call it off in the very last minute due to bad weather.
Last but not least there’s a special competition among photographers; it’s totally unofficial and called “the white shirt contest”. Shoot a woman in a white shirt and make everybody “feel” the texture of that shirt. I give it a try on every shoot and very few pictures come out the way I wish. Go for it - it’s way harder than I thought!
There are websites where models and photographers can present their work and get in contact. The biggest-one worldwide is modelmayhem.com, and I highly recommend to become a member. Another good place is tumblr.com, but you have to go through a lot of dirt before you find some true gems. I have made contact via both sites and I recommend them.
You will need some pictures in your portfolio in order to show that you are - in fact - a photographer with a basic idea of portrait-work. If you shoot portraits (I mean really portraits, not some snapshots of granny and the kids under the Christmas-tree), you probably have enough photos on your disk to state the point. But if you don’t and you want to start (nude) portraits, spend some money on a workshop. I did that twice and it really helped me in several ways: communication with the model, how to start a session, do’s and don’ts - and at the end of the day you will drive home with a handful of pictures for your portfolio.
Speaking of gear, what are you shooting with currently (or what is your favorite setup)?
Gear is overrated. I am with Nikon since 1979 and today I own and use two bodies: a 1975 Nikon F2 photomic (bought used in 82), loaded with Kodak Tri-X and a Nikon D610 DSLR. 90% of my pictures are shot with a 50mm standard lens. Next on the list is the 35mm - you will need that in small rooms when the 50mm is already a bit too long and you want to keep some distance. I happen to own a 85mm, but the locations I book and shoot rarely offer enough space to make use of that lens.
There are these cheap, circular 1m silver reflectors on amazon. They cost about 15 €/$ and you get a crappy stand for the same price. That stuff is pure gold - I use the reflector a lot and I highly recommend to learn how to work with it. It’s my little secret weapon when I shoot against the light (see Alice here above).
A camera with a reasonably fast standard lens, a second battery and a silver reflector is all I need. The rest is luxury for me, but I am pretty much a one-trick-pony. Other photographers will benefit more from a bigger kit.
Most of your images appear to be making great use of natural light. Do you use other lighting gear (speedlights, monoblocks, modifiers, etc)?
Right - available light is where it’s at. I very rarely shoot with a flash kit today because it distracts me from the work with the model. I’m a loner on the set, no assistants or friends who come and help, so everything must be totally simple and foolproof.
Saying that, I own an alarming number of speedlights, umbrellas, triggers and softboxes, but I don’t need that gear very often. I try to visit the locations before I shoot. I check the directions and plan for a realistic timeframe, so today I will neither find myself in a totally dark dungeon nor in a sun-filled room with contrasts à gogo. Windows to the west - shoot in the morning, windows facing south-east: shooting in the (late) afternoon.
Here’s a shot of Karolina Lewschenko. We took this photo in a hotel room by the end of October and the available (window) light got too weak, so I used an Aurora Firefly 65 cm softbox with a Metz speedlight and set-up some classic Rembrandt-Light. I packed that gear because I knew that our timeframe wasn’t guaranteed to work out perfectly. “Better be safe than sorry”.
Do you pre-visualize and plan your shoots ahead of time usually, or is there a more organic interaction with the model and the space you’re shooting in?
Yes, I do. When I visit a place, a possible location, I have some Ideas of where to shoot, what furniture to push around and what pose to try. I can pretty much see the final picture (or my idea of it) before I book the model. Having said that, you know that no battle-plan has ever survived the first shot fired…
When the model arrives, we take some time to walk around the locations and discuss possible sets. We will then start to shoot fully clothed in order to get used to another and see how the light will be on the final shots. It’s very important for me to get feedback from the model. She might say that a pose is difficult for her or hurts after a few seconds, that she’s not comfy with something or that she would like to try a totally different thing here. I always pay a lot of attention to those ideas and - out of experience - those shots based on the model’s ideas are in general among the best of the day.
I mean we’re not here because I shoot bugs or furniture, you don’t give me the opportunity to express myself here because you are a fan of crickets; all the attention is linked to the beautiful women on my photos and how they connect with the beholder. I am just the one who captures the moments, it’s the models who fill those moments with intensity and beauty. It would be very stupid of me not to cooperate with a model who knows how to present herself and who comes up with her own ideas.
Always listen to the model, always communicate, never go quiet.
The discussion with the model also includes what degree of nudity we consider. So the second round of photos starts with the “open shirt” or topless shots before the model undresses completely. If we take photos in lingerie, we do that last (after the nudes) because lingerie often leaves traces on the skin and we don’t want that to show.
It is important to know what to do and in what order. You don’t want to have a nude model standing in front of you, asking “what’s next?” and you answer “I dunno - maybe (!) try this or that again”. If you lose your directions for a moment, just say so or say “please get your bathrobe and let’s have a look at the last pictures together”. If you are “not sure”, the model might be “not comfy”, and that’s something we want to avoid.
Would you describe your workflow a bit? Which projects do you use regularly?
A typical session is 90 to 120 minutes and I will end-up with about 500 exposures on the SD-card and maybe a roll of exposed Kodak Tri-X. The film goes to a lab and I will get the negatives and scans back within 15 to 30 days.
There’s two SD-cards, one with RAW files that I import with gThumb to /photos/year/month/day. The other card holds fine-quality JPG and those go to /pictures/year/name_of_model. My camera is already set to monochrome, I get every picture I shoot in b/w on the camera-screen and the JPG-files are also monochrome.
Next step is a pre-selection in Geeqie. That’s one great picture viewer and I delete all the missed shots (bad framing, out of focus etc.) and note/mark all the promising/good shots here. This is normally the end of day one.
Switching from RAWstudio to darktable has been a giant step for me. dt is just a great program and I still learn about new functions and modules every day. The file comes in, is converted to monochrome and afterwards color saturation and lights (red and yellow) are manipulated . This way I can treat the skin (brighter or darker) without influencing the general brightness of the picture. Highlights and lowlights may be pushed a bit to the left and I add the signature and a frame 0,5% wide, lens correction is set automatically. That’s the whole deal. On very rare occasions I add some vignette or drop the brightness gradually from top to bottom, but again: it doesn’t happen all that often. I never cut, crop or re-frame a shot. WYSIWYG. Cropping something out, turning the picture in order to get perfectly vertical lines or the likes - it all feels like cheating. I have no client to please, no deadline to meet, I can take a second longer and frame my photo when I look through the viewfinder.
The photos will then be treated in the GIMP. Some dodge and burn (especially when there are problematic, very high or low contrasts), maybe stamp an electric plug away and in the end I re-size them down to 2560 on the long side (big enough for A3 prints) and (sometimes) apply the sharpening tool with value 20 or 25. Done. I can’t save a crappy shot in post-prod and I won’t try. Out of the 500 or so frames, 10 to 15 will be processed like that and it feels like nothing has changed over the last 40 years. The golden rule was “one good shot per roll of film” and I happen to be there, too. Spot-on!
I load those 15 pictures up on my Flickr account and about once or twice a week I place a shot in the many Flickr groups. Also once a week (or every ten days) I post a photo on my Tumblr account. Today I have about 5k followers and my photos are seen between 500’000 and one million times a month, depending on the time of year and weather. There’s less traffic on warm summer days and more during cold and rainy winter-nights.
It takes me some time before I add a shot to my own website. In comparison I show few photos there, every one for a reason and I point point people to that address, so I hope I only show the best.
Is your choice to use Free Software for pragmatic reasons, or more idealistic?
I owned an Apple II in 1983 and a digital MicroVax in 1990 or so. My way to FOSS started out pragmatic and it became a conviction later on. In the late 90’s and early 2000’s I had my own small business and worked with MS Office on a Win NT machine. Photos were processed with a Nikon film-scanner through the proprietary software into an illegal copy of Adobe PS4. It was OK, stable and I didn’t fear anything, but I wasn’t really happy neither. One day I swung over to Star-Office/OpenOffice.org for financial reasons and I also got rid of that unlicensed PS and installed the GIMP (I don’t know what version, but I upgraded some time later to 1.2, that’s for sure). I had internet access and an email address since 1994, but in the late 90’s big programs still came on CDs attached to computer-magazines. Downloading the GIMP was out of question.
Gaming was never my thing and when I installed Win XP, all hell broke lose - keeping a computer safe, virus-free and running wasn’t easy before the first service pack, but MS reacted way too slow in my opinion - I tried debian (10 CD kit) on my notebook, got it running, found the GIMP and OOo - and that was it. It took a bit of trial and error and I had to buy a number of W-Lan sticks because very few were supported and so on, but in the end I got the machines running.
Later on I got hold of an Ubuntu 7.10 CD, tried that and never looked back. The few changes on my system were from Gnome to XFCE desktop and from Thunderbird to a browser-based mail-client. Xubuntu is a no-brainer, it runs stable and fast. I contribute every December 100.- € to FOSS. That’s in general 50 and 40 to two projects and a tenner to Wikipedia. I’d spend an extra tenner to any project that helps to convert old star-office files (.sdw and so on) to today’s standards (odt…), but nobody seems interested.
What is one piece of advice you would offer to another photographer?
Don’t take any advise from me, i’m still learning myself. Or wait: be kind and a gentleman with the models. They all - each and everyone of them - have had bad experiences with photographers who forgot that the models are nude for the camera, not for the man behind it. They all have been in a room with a photographer who breathes a bit too hard and doesn’t get his gear working … don’t be that arsewipe!
Arrange for a place where the model can undress in privacy - she didn’t come for a strip-show and you shouldn’t try to make it one. Have some bottles of water at hand and talk about your plans, poses and sets with the model. Few people can read minds, so communication works best when you say what you have in mind and the model says how she thinks this can be realized. The more you talk, the better you communicate, the better the pictures. No good photo has ever been shot during a quiet session, believe me.
In general the model will check your portfolio/website and expect to do more or less the same kind of work with you. If you want to do something different, say so when booking the model. If your website shows a lot of nude portraits, models will expect to do that kind of photos. They may be a bit upset if you ask them out of nowhere to wear a latex suit because it’s fetish-Friday in your world. The more open and honest you are from the beginning, the better the shooting will go down.
Don’t overdo the gear-thingy. 90% of my photos are taken with the 50mm standard lens. Period. Sometimes I have to switch to 35mm because the room is a bit to small and the distance too close for the one four-fifty, so everything I bring to an indoor-shooting is the camera, a 50, a 35, an el-cheap-o 100cm reflector from amazon (+/- 15 €/$) and an even cheaper stand for the reflector. Gear is not important, communication is.
Want to spend 300 €/$ on new gear? Spend it on a workshop. Learn how to communicate, get inspiration and fill your portfolio with a first set of pictures, so the next model you email can see that you already have some experience in the field of (nude) portraits. That’s more important than a new flashlight in your bag.
I want to thank Stefan again for taking the time and being patient enough to chat with me!
Stefan is currently living in Northern France. Before that he lived and worked in Miami, FL, and Northern Germany where he is from, went to school, and met his wife. His main website is at https://whatstefansees.com/, and he can be found on Flickr, Facebook, Twitter, Instagram, and Tumblr.
Unless otherwise noted, all of the images are copyright Stefan Schmitz (all rights reserved) and are used with permission.
In popular science books, including 'Seven Brief Lessons on Physics' and 'Reality Is Not What It Seems', the Italian theoretical physicist Carlo Rovelli has studied the phenomena – namely time and space – that structure our very existence. In doing so, he has become something of a phenomenon himself, praised for his charm, clarity and humour – things we might not immediately associate with the field of quantum gravity. Here, the TLS's Samuel Graydon asks him about his new book The Order of Time
How do we account for Richard Nixon's stubborn unpopularity? Sure, he was a liar and a crook, but that has not stopped the rehabilitation of many a politician – as a new biography appears Barton Swaim joins us to discuss; why is it that certain ailments suffered by women are so scarcely discussed or resolved? Leonore Tiefer considers endometriosis and a "legacy of disinterest"; “The world is far more complicated than what we see”, says the theoretical physicist Carlo Rovelli, putting it mildly. Reality “is mind-blowing” – here, he discusses the structure of time with the TLS's Samuel Graydon
Books
Richard Nixon: The Life by John A. Farrell
The Order of Time by Carlo Rovelli
Ask Me About My Uterus: A quest to make doctors believe in women's pain by Abby Norman
A camera profile is often a combination of a color lookup table (LUT) and a tone
curve which is applied to a RAW file to get a developed image. It translates
the colors that a camera captures into the colors they should look like. If you
shoot in RAW and JPEG at the same time, the JPEG file is already a developed
picture. Your camera can do color corrections to the data it gets from the
sensor when developing a picture. In other words, if a certain camera tends to
turn blue into turquoise, the manufacturers internal profile will correct for
the color shift and convert those turquoise values back to their proper hue.
The camera manufacturer creates a tone curve for the camera and understands
what color drifts the camera tends to capture and can correct it. Also RAW
files normally look very dull and the profile will allow it to look more
pleasing with just one click. We can mimic what the camera does using a tone
curve and a color LUT. We want to do this as the base curves provided by
darktable are generalized for a manufacturers sensor behavior, but individually
profiling your camera can provide better color results.
Why do we want a color profile?
The camera captures light as linear RGB values. RAW development software needs
to transform those into CIE XYZ tristimulus
values for mathematical
calculations. The color transformation is often done under the assumption that
the conversion from camera RGB to CIE XYZ is a linear 3x3 mapping. Unfortunately
it is not because the process is spectral and the camera sensor sensitivity
also absorbs spectral light. In darktable the conversion is done the
following way: The camera RGB values are transformed using the color matrix
(either coming from the Adobe DNG Converter or dcraw) to arrive at
approximately profiled XYZ values. darktable provides color lookup table in
Lab color space to fix
inaccuracies or implement styles which are semi-camera independent. A very cool
feature is that a user can edit the color LUT. This color LUT can be created by
darktable-chart as this article will show so that you don’t have to create it
yourself.
What we want to have is the same knowledge about colors in our raw development
software as the manufacturer put into the camera. Therefore we have two ways to
achieve this. Either we fit to a JPEG generated by the camera, which can also
apply creative styles (such as film emulations, filters), or we profile against
real color reproduction. For real color a color
target ships with a file providing the color values for each patch it has.
In summary, we can create a profile that emulates the manufactures color
processing inside the body, or we can create a profile that renders real color
as accurately as possible.
The process for both is nearly identical, and we will note when it diverges in
the instructions.
Creating pictures for color profiling
To create the required pictures for camera profiling we need a color chart
(aka Color Checker) or an IT8
chart as our target. The
difference between a color chart and IT8 chart is the number of patches and
often the price. As the IT8 chart has more patches the result will be much
better. Optimal would be if the color target comes with a grey card for
creating a custom White Balance. I can recommend the X-Rite ColorChecker
Passport Photo.
It is small, lightweight, all plastic, a good quality tool and also has a gray
card. An alternative is the Spyder
Checkr.
If you want a better profiling result, you can buy a good IT8 chart from Coloraid
(you want C1) or invest for example in the ColorChecker Digital
SG.
(Please share you experience if you buy a Coloraid C1!). I recommend getting
a gray card as this makes profiling easier.
Note: ArgllCMS offers CIE and CHT files for different color charts, if you
already have one or are going to buy one, check if ArgyllCMS offers support for
it first! You can always add support to your color chart to ArgylCMS, but the
process is much more complex. This will be very important later!
You can find these files (generally) in:
/usr/share/color/argyll/ref/
The path might differ depending on the distribution you’re using. Your package
management tool should provide a way to list all files of a package so it should
be easy to find.
find /usr/share -name "*.cht"
is a possible alternative to track down where the files are located.
We are creating a color profile for direct sunlight conditions (D50) which can
be used as a general purpose profile. For this we need some special conditions.
The Color Checker needs to be photographed in direct sunlight at 5000K (K =
Kelvin), which helps to reduce any metamerism of colors on the target and
ensures a good match to the data file that tells the profiling software what
the colors on the target should look like. However a major concern is glare,
but we can reduce it with some tricks.
One of the things we can do to reduce glare, is to build a simple shooting box.
For this we need a cardboard box and at least three black T-Shirts. The box
should be open on the top and on the front like in the following picture
(Figure 1).
Figure 1: Cardboard box suitable for color profiling
Normally you just need to cut one side open. However it is better if you use
one big cardboard and build the box yourself. This way you can make the box so
it widens up in the front, see Figure 1. Then coat the inside of the box with
black T-Shirts like this:
Figure 2: A simple box for color profiling
To further reduce glare we just need the right location to shoot the picture.
We want to shoot the target when the sun provides a temperature of 5000K (D50).
We get that in the morning hours when the sun is at about 45° in the sky. It
varies on where on earth you are located and on the season of the year.
I took my shots in central Europe in mid October at 09:45.
To measure 5000K I used a gray card for white balancing. When I shoot the gray
card, my camera displayed which temperature the profile has.
Try to shoot on a day with minimal clouds so the sun isn’t changing intensity
while you shoot. The higher the temperature the more water is in the
atmosphere, which means the quality of the images for profiling might be
reduced. Temperatures below 20°C are better than above.
In some countries it may not be possible to accurately produce these images
with sunlight. This could be due to air pollution (or lack of), temperature,
humidity, latitude, and atmospheric conditions. For example, in Australia, one
might be unable to use direct sunlight to create this profile, and would have
to use a set of color balanced bulbs with the same box setup to create this.
Shooting outdoor
If you want to shoot outdoor, look for an empty tared parking lot or a lonely
road. The parking lot should be pretty big, like from a mall, without any cars
or trees! You should be far away from walls, trees or anything which could
possibly reflect. Put the box on the ground or a small chair and shoot with the
sun above your right or left shoulder behind you. You can use a black fabric
(bed sheets) if the ground reflects.
Shooting indoor with artificial light
Avoid all windows and stained glass. Create the box as mentioned, and arrange
it in a V shape with your tripod. At the top left of the V is the camera, at
the bottom is the color target, and at the top right is the light source. The
right source should be bright and even across the room and your setup. Position
yourself underneath it to avoid all shadows.
How to shoot the target?
Outdoor preparations
Start white balancing your camera outside your house, office etc. with a
gray card every hour or 30 mintues in the morning and write down the time
and temperature. This way you will find out when the sun provides the right
temperatue (5000K) to take pictures for your target.
Taking the pictures
Preparations at home
If you’re shooting outdoor, do the following preparations at home. You will not
have much time for taking the pictures of your target. You only have a Window
of about 10 minutes. An assitent in the field can be useful.
You should use a prime lens for taking the pictures. If possible a 50 mm or
85 mm lens (or anything in between, numbers are for full frame). The less
glass the light has to travel through the better it is for profiling. Thus
those two lenses are a good choice in the number of glass elements they have
and their field of view and also vignetting! With a tele lens we would be
too far away and with a wide angle lens we would need to be too near to have
just the black box in the picture.
Set your metering mode to matrix metering (evaluative metering or multi
metering - this is often a symbol with 4 boxes and a circle in the center)
and use an aperture of f/8.0 (+/- 1/3 EV).
[If you have a spot metering mode which isn’t fixed on the center, then you
can point it to the neutral gray patch of the color checker, that’s the one
we want to have exposed correctly.]
Make sure that Dynamic Range Optimization (DRO) and Auto HDR (High Dynamic
Range) or anything like that are turned off!
Set the camera to capture “RAW & JPEG” and disable lens corrections
(vignetting corrections) for JPEG files if possible. This is important
for JPEG and real color fitting. You can leave corrections for color
failures turned on.
Set your camera to color profile to AdobeRGB.
Set the ISO to the lowest possible value. Some cameras have an extended
ISO range, don’t use any of those values. For example my camera offers ISO
50, ISO 64 and ISO 80. Those are extended ISO values. The lowest ISO not in
the extended range for my camera is ISO 100. Check your camera manual!
Wear dark cloths, the best is a black hoody with long sleeves :-)
In the field
Be there in advance so you have time to prepare everything.
Set up your shooting box and mount your camera on a tripod. The best is to
have the camera looking down on the color chart like in the following
picture:
Figure 3a: Camera setup for creating pictures of the Color Checker
Make sure the color chart is parallel to plane of the camera sensors
so all patches of the chart are in focus. The color chart should be in the
middle of the image using about 1/3 of the screen so that vignetting is
not an issue.
Shoot the target, zoom to 100% and check for glare and reposition if
necessary! In Figure 3b you can see a patch with extreme glare. In Figure 3c
you can see a patch with a bit of glare. You should try to get no glare at
all. Make sure the sun is shining at an angle on the Color Checker. Change
the angle of the target in to box till you get no glare!
Figure 3b: The target with extreme glare cause by a wrong angle of the sun shining on the target
Figure 3c: The target with some glare cause by a wrong angle of the sun shining on the target
If your camera has a custom white balance feature and you have a gray card,
create a custom white balance profiles till you get 5000K (D50) and use it
(see figure 3). Put the gray card in your black box in the sunlight or
artificial light at the same position as the Color Checker. If you don’t
have a gray card, you have to use Auto White Balance (AWB) and find other
ways how to measure when you get 5000K from the sun.
Once you get 5000K from the the sun, you have about 10 minutes to take the
pictures of your target!
Now you want to begin taking images. Normally we want to have a camera profile
just for the lowest ISO value.
Note: I created profiles for ISO 100 to ISO 640, because my camera has a gain
switch at ISO 640. I learned about that by inspecting the charts which have
been measured by DPReview.
You need to take 5 pictures of your target. This is so that if an image is over
or under exposed, you have an image with a stop above or below that is then
exposed correctly. One photo for -0.3 EV, 0 EV, 0.3 EV, 0.7 EV and 1.0 EV.
Some cameras (Fuji) ISO 100 is an Extended value, so use ISO 200. Normally
Extended ISO values are captured with the lowest physical ISO and overexposed and then
exposure is reduced with image processing. Use the lowest ISO profile for them.
Hint: Some cameras have a “Continues Bracketing” feature. You can set this to
0.3EV and 5 Images. Then the camera will automatically capture 5 images in 0.3
EV stops (-0.3 EV, 0.0 EV, 0.3 EV, 0.7 EV, 1.0 EV) for you.
Once you have done all the required shots, it is time to download the RAW and
JPEG files to your computer.
Verifying correct images in darktable
For verifying the images we need to know the L-value from the Lab color
space of the neutral gray field
in the gray ramp of our color target. For the ColorChecker Passport we can look
it up in the color information (CIE) file
(ColorCheckerPassport.cie) shipping with
ArgyllCMS, which should be located at:
The ColorChecker Passport has actually two gray ramps. The neutral gray field
is the field on the bottom right of the color target ramp and is called D1 (see
Figure 4). For the ColorChecker SG it is the patch E5 and for Wolf Faust’s IT8
target the one on the left of the gray ramp (GS0). It should be described in the
specification of your target.
If we check the CIE file, we will find out that
the neutral gray field D1 has an L-value of: L=96.260066. Lets round it to
L=96. For other color targets you can find the L-value in the description or
specification of your target, often it is L=92 (e.g. Wolf Faust’s IT8 GS0).
Better check the CIE or CGATS file!
You then open the RAW file in darktable and disable the base
curve and all
other modules which might be applied automatically! You can leave the
Orientation module turned on. Select the standard input matrix in the
input color profile
module and disable gamut clipping. Make sure “camera white balance” in the
white balance
module is selected. If lens corrections are automatically applied to your JPEG
files, you need to enable
lens corrections
for your RAW files too! Only apply what has been applied to the JPEG file too.
For my configuration I was left with the following modules enabled:
Output Color Profile
Input Color Profile
Lens Correction (Optional)
Crop & Rotate (Optional)
Demosaic
White Balance
Raw Black/White Point
Apply the changes to all RAW files you have created!
You could consider making a “profiling” style and applying it en-masse.
You can also crop the image but you need to apply exactly the same crop to the
RAW and JPEG file! (This is why you use a tripod!)
Now we need to use the global color picker
module in
darkroom to find out the value of the natural white field on the color target.
Open the first RAW file in darkroom and expand the global color picker module
on the left.
Select area, mean and Lab in the color picker and use the eye-dropper
to select the natural gray field of your target. On the Color Checker it’s
on the bottom right. Here is an example:
Figure 4: Determining the color of the neutral white patch
If the value displayed in the color picker module matches the L-value of the
field or is close (+0/-2. This means L=94 to L=96 is acceptable), give the RAW
file and the corresponding JPEG file 5
stars. In the picture above it is the first value of: (96.491, -0.431,
3.020). This means L=96.491, which is what you’re looking for on
this color target. You might be looking for e.g. L=92 if you are using a
different Color Checker. See above how to find out the L-value for your
target.
For real color profiling this is very important to get right. Additionally
you want to check the JPEG is registering a L value between 96 and 98 (0/+2
tolerance). You do not want overexposure here (L=100 is white)! If your
images are over exposed, your profile will actually darken the images (this
is not what you want).
For profile extraction, this is less important as darktable-chart will extract
the differences between the raw and the JPEG, and will assume the camera’s
exposure level was correct. This means if your camera “thinks” a good exposure
is L=98 for the JPEG, and the RAW reads as L=85, then your profile needs to
create the difference here so you get the same effect.
Exporting images for darktable-chart
For exporting we need to select Lab as output color profile. This color space
is not visible in the combo box by default. You can enable it by starting
darktable with the following command line argument:
darktable --conf allow_lab_output=true
Or you always enable it by setting allow_lab_output to TRUE in darktablerc. Make
sure that you have closed darktable before making this change, then reopen it (
darktable writes to this file and may erase your change if you edit while
darktable is running).
Remember to select the Lab output color profile here as well.
You need to export all the RAW and JPEG files, not just the RAWs.
Select all 5 star RAW and JPEG files and export them.
Figure 5: Exporting the images for profiling
Profiling with darktable-chart
Before we can start you need the chart file for your color target. The chart
file contains the layout of the color checker. For example it tells the
profiling software where the gray ramp is located or which field contains
which color. For the “X-Rite Colorchecker Passport Photo” there is a
(ColorCheckerPassport.cht) file provided by
ArgyllCMS. You can find it here:
Now it is time to start darktable-chart. The initial screen will look like
this:
Figure 6: The darktable-chart screen after startup
Source Image
In the source image tab, select your PFM exported RAW file as image and for
chart your Color Checker chart file. Then fit the displayed grid on your
image.
Figure 7: Selecting the source image in darktable-chart
Make sure that the inner rectangular of the grid is completely inside of the
color field, see Figure 8. If it is too big, you can use the size slider in the
top right corner to adjust it. Better too small than too large.
Figure 8: Placing the chart grid on the source image
Reference values
This is the only step where the process diverges for real color vs camera
profile creation.
If you are creating a color profile to match the manufacturers color
processing in body, you will want to select color chart image and as the
reference image select the PFM exported JPEG file which corresponds to the
RAW file in the source image tab. Once opened you need to resize the grid again
to match the Color Checker in your image. Adjust the size with the slider if
necessary.
Figure 9: Selecting the reference value for profiling in darktable-chart
If you are creating a color profile for real color, select the mode as
cie/it8 file and load the corresponding CIE file for your color target. If
you have issues with this, run darktable-chart from the CLI and check the output.
I found that my chart would not open with:
error with the IT8 file, can't find the SAMPLE_ID column
It’s worth checking the ‘Lab (reference)’ values at the bottom of the display
to ensure they match what you expect and were correctly loaded. I saw some
cool (but incorrect) results when they did not load!
Process
In this tab you’re asked to select the patches with the gray ramp. For the
‘X-Rite Color Checker Passport’ these are the ‘NEU1 .. NEU8’ fields. Newer
version of darktable automatically detect the gray ramps! The input field
number of final patches defines how many editable color patches the resulting
style will use within the color look up table module. More patches give a
better result but slows down the process. I think 28 is a good compromise but
you might want to user the maxium of 49.
Once you have done this click on ‘process’ to start the calculation. The
quality of the result in terms of average delta E and maximum delta E are
displayed below the button. These data show how close the resulting style
applied to the source image will be able to match the reference values – the
lower the better.
You must click process each time you change source images or reference chart
to generate the new profiles. Sometimes process is “greyed out”, so simply
toggling the grey ramp setting will reactivate it.
After running ‘process’, click on ‘export’ to save the darktable style.
Figure 10: Processing the image in darktable-chart
In the export window you should already get a good name for the style. Add a
leading zero for ISO values smaller than 1000 get correct sorting in the styles
module, for example: ILCE-7M3_ISO0100_JPG.dtstyle. The JPG in the name should
indicate that we fitted against a JPG file. If you fitted against a CIE file,
remove the CIE filename from the style name. If you applied a creative style
(for example, a film emulation or filter in the camera). to the JPG, probably
add it at the end of the file name and style name.
Importing your dtstyle in darktable
To use your just created style, you need to import it in the style
module in the lighttable.
In the lighttable open the module on the right and click on ‘import’. Select
the dtstyle file you created to add it. Once imported you can select a raw file
and then double click on the style in the ‘style module’ to apply it.
To verify the style you created you can either apply it to one of the RAW files
you created for profiling. Then use the global color picker to compare the
color in the RAW with the style applied to the one in the JPEG file.
I also shoot a few normal pictures with nice colors like flowers in RAW and
JPEG and then compare the result. Sometimes some colors can be off which can
indicate that your pictures for profiling are not the best. This can be because
there were some kind of clouds, glare or the wrong daytime. Redo the shots till
you get the result you’re satisfied with.
Sadly this is a trial and error process, so you will have to create some number
of profiles before you find the results you want. It’s a good idea to
read this article again to see if you missed any important steps.
How does the result look like?
In the following screenshot (Figure 11) you can see the calculated tone curve by darktable
chart and the Sony base curve of darktable. The tone curve is based on the color LUT. It will
look flat if you apply it without the LUT.
Figure 11: Comparison of the default base curve with the new generated tone curve
Here is a comparison between the base curve for Sony on the left and the
dtstyle (color LUT + tone curve) created with darktable-chart:
Figure 12: Side by side comparison on an image (left the standard base curve, right the calculated dtstyle)
Other ideas
This process will work for extracting in-body black and white profiles, as
well as creative color profiles. I see a significant improvment in black
and white profiles from this process over the use of some of the black and white
modules in darktable.
You may find that the lowest ISO profile may provide pretty good results for
higher ISO values. This will save you a lot of time profiling, and allows
you to blanket-apply your profile to all your images quickly - you only
need one profile now! This is highly
dependant on your camera however, so experiment with this.
These profiles should work in all light conditions, provided your white
balance is correct. Given you now have a color target, you should always take
one photo of it, so you can correct the whitebalance later.
Discussion
As always the ways to get better colors are open for discussion an it can be
improved in collaboration.
Feedback is very welcome.
Thanks to the darktable developers for such a great piece of software! :-)
William Brown has contributed to the article, based on his profiling experience
following this tutorial.
Martin Rowson, cartoonist for the Guardian and elsewhere, joins us to discuss caricature as political hit-job; the TLS's Arts editor Lucy Dallas considers the jolly japes and scrapes of the Beano, as that publication marks its eightieth year; and our Features editor Rozalind Dineen goes to meet Jesmyn Ward, a writer described in our pages as “an important new voice of the American South – one developing, perhaps, into the twenty-first-century’s answer to William Faulkner”
Books
The Communist Manifesto: A Graphic Novel, adapted by Martin Rowson
The Fire This Time: A New Generation Speaks about Race by Jesmyn Ward
With Stig Abell and Lucy Dallas. Lionel Shriver castigates the arrogant British for snootiness over American English; David Coward tells the story of Simon Leys, "the man who did for Mao" and who called Sartre a "windbag"; and Kate Bingham reads her poem "This hair".
Noise in digital images is similar to film grain in analogue photography. In
digital cameras, noise is either created by the amplification of digital
signals or heat produced by the sensor. It appears as random, colored speckles
on an otherwise smooth surface and can significantly degrade image quality.
Noise is always present, and if it gets too pronounced, it detracts from the
image and needs to be mitigated. Removing noise can decrease image quality or
sharpness. There are different algorithms to reduce noise, but the best option
is if having profiles for a camera to understand the noise patterns a camera
model produces.
Noise reduction is an image restoration process. You want to remove the digital
artifacts from the image in such a way that the original image is discernible.
These artifacts can be just some kind of grain (luminance noise) or colorful,
disturbing dots (chroma noise). It can either add to a picture or detract from
it. If the noise is disturbing, we want to remove it. The following pictures
show a picture with noise and a denoised version:
To get the best noise reduction, we need to generate noise profiles for each
ISO value for a camera.
Creating the pictures for noise profiling
For every ISO value your camera has, you have to take a picture. The pictures
need to be exposed a particular way to gather the information correctly. The
photos need to be out of focus with a widespread histogram like in the
following image:
We need overexposed and underexposed areas, but mostly particularly the grey
areas in between. These areas contain the information we are looking for.
Let’s go through the noise profile generation step by step. For easier creation
of the required pictures, we will create a stencil which will make it easier to
capture the photos.
Building a profiling testbed
Requiements
A dark room (wait till night time)
Monitor
Printer
Sheets of black thick paper (DIN A3, >= 200g/m²)
White paper
Scissors
Sellotape (Tesafilm)
First you need to get some thicker black paper or cardboard. No light should shine
through it! Then you need to print out a gradient on white paper. Light
should shine through the white paper!
I got black thick paper (DIN A3, >= 200g/m²) and used two sheets. You need to
be able to cover your monitor with the black paper. Put the printed gradient in
the middle and draw around it. From three sides (bottom, left, top) make the
window smaller by 1 cm, see Figure 1. On the right we need to have a gap.
Figure 1: Drawn window reduced by 1 cm on the bottom, left and top.
Next is to cut out the window and type the gradient onto the black paper like
in Figure 2. It is important that there is a gap between the white and the
black paper on the white side of the gradient. We need light for an overexposed
area.
Figure 2: The gradient taped into the window of the black paper.
Once you have done that go to your monitor and make it all white. You can an
all white image for that. Then tape the sheets to your monitor
like in Figure 3.
Figure 3: The sheets of black paper taped to the monitor.
Taking the pictures
It is time to get your camera. You need to shoot in RAW. It is best to turn off
any noise reduction especially long exposure noise reduction. Mount the camera
on a tripod and use a lens between 35 mm to 85 mm (full frame). I used a 85 mm
f/1.4 lens.
Make sure the gradient fills most of the frame. Set your camera to manual focus
and focus on infinity. Select the manual mode of your camera and choose the
fastest aperture and ISO100. Depending on the lens you’re using you might want
to close the aperture. For me f/1.4 was too blurry and I closed it till f/4.0.
You don’t want to see any edges or any structure on the paper but be too
blurry. You want to still see the gradient but we want nice transitions between
different lightning zone black -> grey -> white like in Figure 4.
Now you need to set the shutter speed. Make the picture really dark and then
make the shutter speed longer till the gap which gives us the white from the
monitor is overexposed, pure white see Figure 4. The black around the white
paper should be underexposed (pure black).
Figure 3: Example shot for noise.
Now you need to take a picture for each ISO value of your camera. When you
increase the ISO value you need to decrease the shutter speed!
If this gives you the help of the tool, continue with STEP 2 otherwise go to
STEP 1a. Packages for openSUSE, Fedora, Ubuntu and Debian packaging the noise
tools can be found
here.
STEP 1a
Your darktable installation doesn’t offer the noise tools so you need to
compile it yourself. Before you start make sure that you have the following
dependencies installed on your system:
This will automatically do everything for you. Note that this can take quite
some time to finish. I think it took 15 to 20 minutes on my machine. If a
picture is not exposed correctly, the tool will tell you the image name and you
have to recapture the picture with that ISO. Remove the non-working picture.
The tool will tell you, once completed, how to test and verify the
noise profiles you created.
Once the tool finished, you end up with a tarball you can send to darktable for
inclusion. You can open a bug here
The interesting files are the presets.json file (darktable input) and, for the
developers, the noise_result.pdf file. You can find an example PDF
here. It is a
collection of diagrams showing the histogram for each picture and the results
of the calculations.
Are we hard-wired to feel other people’s pain? And if so, is it necessarily a good thing? Andrew Scull has reviewed three new books on empathy and joins us to tell us more; Charles Dickens's love of all things theatrical – in life as in art – is no secret. Robert Douglas-Fairhurst considers fifty years' worth of Dickens adaptations for the stage (and film)
Books
The Empathy Instinct by Peter Bazalgette
Against Empathy: The case for rational compassion by Paul Bloom
The Invention of Humanity: Equality and cultural difference in world history by Siep Stuurman
Dickensian Dramas: Plays from Charles Dickens (Volume One, edited by Jacky Bratton; Volume Two, edited by Jim Davis
Who are the most exciting novelists from the British Isles currently working? In a spirit of mischief, the TLS asked 200 notable names in the publishing industry (editors, agents, publishers and writers) to nominate those at the top of their literary game. The critic Alex Clark and TLS fiction editor Toby Lichtig join us in the studio to pick through the results
The political philosopher John Gray discusses the failures of liberalism; as the TLS publishes its 6,000th issue, Ruth Scurr delves into the back issues to explore how the paper has changed, and how it reflects literary culture more broadly; the TLS's poetry editor Alan Jenkins reads two of his favourite poems from the past century: D. J. Enright 's "The Laughing Hyena, by Hokusai" and "In Your Mind" by Carol Ann Duffy
Literary prizes come in more shapes and sizes than ever before: we have prizes that echo the Man Booker, and prizes that set out not to be the Man Booker; we have prizes for first novels, second novels, crime novels that don’t feature violence against women, and, more satirically, a prize for “bad sex in fiction”. Why do we need so many? Do we need them at all? And how do prizes work not only for writers but for those people who do all the reading (and sometimes arguing): the judges? The TLS's Michael Caines chairs a lively discussion between Toby Lichtig, the fiction editor of the TLS, and Alex Clark, a critic and regular prize judge/chair. This live event was a collaboration with BookMachine.
Science reporter Jennie Erin Smith joins us to discuss our desire, or evolutionary compulsion, to delve into the minds of other animals, from cows and penguins to the dismally misunderstood hyena; the TLS's George Berridge shares new insights into the work of Cormac McCarthy and the various (failed) attempts at adapting his novels; much has been said about how literary blogs killed off 'proper', print criticism. Jennifer Howard explains why the picture is far more complicated, and positive, than that
O artista Hélio Ziskind fala um pouco mais sobre a música Amigos do Peito e seu processo de criação.
Conheça o novo canal do Hélio Ziskind, o ZiS: http://goo.gl/j9YhRn
Venha conferir a nova versão de Amigos do Peito: https://goo.gl/Ro41eR
Miranda Seymour reveals the peculiar circumstances surrounding the marriage of Lord Byron's daughter and his super-fan, William King; just how seriously should we be taking the Virtual Reality revolution? Tom Rachman cautiously probes the frontier of what is possible; Death Row attorney Clive Stafford Smith shares the story of Billy Neal Moore, a tale of murder, hope and Mother Theresa; and finally, before the winner of the Republic of Consciousness Prize for small presses is revealed, the TLS's Fiction editor Toby Lichtig meets Neil Griffiths, the prize's founder, to find out more
Dale Salwak, the editor of a new collection of essays, tells us why he wanted to probe this most complicated of relationships, while Judy Carver, the daughter of William Golding – he of Lord of the Flies – sheds light on her father’s difficult relationship with his mother; Charlotte Shane introduces us to Marjorie Hillis, who, in the 1930s, taught American women how to "live alone and like it"; finally, TLS editor Catharine Morris considers the difficult genesis of Latvian literature
David Baddiel – comedian and, as per his Twitter profile, Jew – joins us to discuss whether Jewishness is inherently funny; as Italians prepare to elect their next prime minister (an unenviable choice between undesirables and impossibles), Tim Parks – author, translator, and resident of Italy – talks us through the excessively complicated mess that is Italy
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