Skin colour in 24MP DX cameras
maybe use a grey card and drop the EV a step or 2
Just keep clicking, something will turn out fantastic.
Nikon D600, D7100, Canon (!) G15, Nikkor 35mm f/1.8, 85mm f/1.8, 50mm f1.4, 70-200 f/2.8 VR II, 24-70 2.8; Tokina 11-16 f/2.8, 16-28 f/2.8
MarkJH wrote:As I understand it, "CCD" and "CMOS" actually refer not to the photo-sensing capacitor or photodiode of each pixel that actually translates received light into a charge state, but rather, to the underlying technology by which that charge state is converted to a voltage quantity that can be remembered or processed.
With a CCD sensor, after you've snapped your photograph and the sensor's exposed, collected charges for each pixel "shift" down rows and columns, where they're read by a single amplification circuit for the row (or column) that converts them, one by one, into a voltages that can be stored or processed. Each pixel gets "dumped" this way. ("CCD" = "Charge Coupled Device," which describes the "shift" of charges down each pixel "bucket".)
By contrast, in a CMOS or "active pixel" sensor, a distinct amplification circuit is a part of each pixel, coupled directly to the sensing photodiode or capacitor. So the voltage conversion process happens on exposure, per pixel, and image data can be stored or processed right away, even on the same integrated circuit as the sensor itself. ("CMOS" = "Complementary Metal Oxide Semiconductor," which refers to the design style of the circuitry, in which pairs of transistors are balanced to perform logic and gating functions.)
Just looking at the raw architecture of it, it's not entirely clear (to me?) why images from a CCD sensor would look different than those from a CMOS sensor. The CMOS advantage of being able to integrate photosensing, reading, storing, and processing functions on a single silicon chip makes plenty of sense from a production and design standpoint. Smaller, lighter, faster, more efficient etcetera.
It is (or was) a matter of the geometry of the silicon. A CMOS sensor has the transistor pair or pairs right on the chip directly next to the pixel vs. a CCD which doesn't. This reduces the amount of area/volume available to the light gathering photo-diode. So other mechanism were employed to compensate. For instance CFA's which may not be as discerning. Another important aspect is the AD converter/sampler which is probably a lot different and tweaked differently as well.
Only from my personal experience, it is best to just ignore and avoid AWB with the D7000. You don't have to spend $100 for an Expo Disk, get an inexpensive $12 one and always perform the In-camera custom white balance, you WILL see a huge difference and this is the only way to get pretty good skin tones out of this camera. Even if you are shooting in RAW don't use AWB and your photos should be even better and easier to adjust in PP.
In the end, the D7000 does not produce THE nicest skin tones, specially tanish skin, period. But people say the D7100 is much much better. I use a CCD camera now and yes, HUGE difference between CMOS sensors. Below are D7000 AWB jpeg examples. Just HORRIBLE!
absolutely. In your firts image for example, the little girl's face looks washed out from details, and the shadows are very dense. If you try to recover those on cmos, you will experiment color shift in the hair and green bushes will lack of color, this is typical cmos. Try it with a CCD : if you expose well, you'll just need to ad some sharpening to your NEF file and voila !
I tend to like the results D7000 AWB gives me, even for those supposedly more challenging darker skin tones:
(As with any example photograph, maybe this one shows terrible skin tones when I'm trying to suggest they're pretty good. Eye of the beholder and all, but the client liked it.)
So many things go into color and skin tone, but I don't think there's an "sensor choice silver bullet." Instead, regardless of what you're shooting, you have to hit your exposure and you have to be aware of what kind of light you're using. I have a CCD-equipped body, too, but swapping it in won't suddenly fix a lousy exposure or unflattering light striking my subject.
Part of making AWB work properly is--you guessed it--sufficient exposure and light that doesn't have a color cast you don't want. Hit your subject with 5400K in a setting that won't bounce that light back with an obnoxious cast, and the D7000's AWB will give you 5400K tones. Under- or over-expose in an environment that's giving you really funky light and, well, it's tough to expect the camera will give you a reasonable white-balance read.
It's often the case that people shoot photographs with their mind rather than with their eyes. You're in a moment, you like it, so you frame and snap without really being aware of the color in front of you. Happens all the time when people shoot their kids posing on soccer fields: we just went through a thread with someone worrying about whether he was seeing the "nikon green cast" rather than the obvious result of posing his subjects atop a giant green reflector. He was in the moment; he didn't actually look at what he was shooting.
So, rather than worry about CCD vs. CMOS, I'd worry about Mental Image vs. Real Image: am I really paying attention to the light and color where I'm photographing? Am I trying to photograph something in totally funky or flat light and unflattering color and then expecting that it'll come out as if lit with Annie Leibovits's army of Softlighter assistants?
After reading your notes here, doing some research etc I ordered a EX+ D200 from KEH and hope I like the results for low ISO portrait work. 10MP is more than plenty for me and if this skin tone issue is solved, I can live with the ISO ceiling these have. BTW what do you consider the high ISO limit to be for these? It has to be better than my E1 I do believe there is a reason they stayed with CCD for medium format pro backs etc..-- hide signature --
Stacey, you will notice the difference. No mushy shadows, no color shift if your image was overexposed or underexposed, no almond paste skin tones in mixed-warm light situations. The images produced by the 10MP CCD are very subtle in terms of tones and details and easy to tone, use Capture NX for the best results. The only downside of the D200 is the screen, but you can read everything trough the viewfinder, so shoot raw and expose right, this is the key. I have shot great pictures at 800 ISO, but for best results, keep it under 400 ISO. Underexposing will produce more noise in the shadows and medium tones, overexposing will produce less noise. You may want to overexpose by 0.3 IL your shots by default
After reading your notes here, doing some research etc I ordered a EX+ D200 from KEH and hope I like the results for low ISO portrait work. 10MP is more than plenty for me and if this skin tone issue is solved, I can live with the ISO ceiling these have. BTW what do you consider the high ISO limit to be for these? It has to be better than my E1 I do believe there is a reason they stayed with CCD for medium format pro backs etc..
I really do hope you like it. Mine's not getting much use. The price was right and I treated it as a learning experience to see if I'd like a step up to a DXXX body. I much prefer the D90, and after carrying around a D200 to work for a few weeks, I went back to carrying a D90.
My forum postings reflect my own opinions and not those of my employer. I'm not employed in the photo business.
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