I understand that the choice of color space to be sRGB or Adobe RGB is only relevant when shooting in JPEG and irrelevant when shooting in RAW. Can you confirm it ?
Furthermore, choosing in the Shooting Menu NEF (RAW) Recording between Lossless compressed, compressed or Uncompressed, do you recommend Uncompressed ?
n the same menu choosing the bit depth to 14 bit instead of 12 bit, does that make a big difference in the quality of the RAW photo ?

What settings you use do have an impact on how the image is rendered on your computer screen.
This is very relevant to changes you may want to try for final use.
Best settings are those that match your intended final use.
sRGB is preferred for computer display and display on the web.
RGB is preferred for nuances, mainly subtleties in tone and color when you do print and see them on a high quality calibrated monitor.
Generally, RGB images are muted when displayed on the web.

Color space settings are only irrelevant in the sense that the image is unaltered as shot when in RAW, and you can later change the color space.

I use Lossless Compressed because its name implies there is no data discarded when saving and yet, it saves disk space.
Compressed losses some data to reduce the file size.
Uncompressed simple doesn't compress and they have the largest file size.
As for bits, the more the merrier. However, in my daily use (the web), I don't see much of a difference -and often none- in image quality, even on wider dynamic range sensors, like those on the D4 and D800.
My personal impression is that the more bits options are in preparation of the wider dynamic range of the near future.

Our experts will surely expand on this topic.

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Thanks for your reply.
If I say that the main purpose of making photos is to sell them in Istockphoto (for further usage by a large community of photo users), what would be your recommendations ?
Should I use in Shooting control vivid colors, or standard or neutral etc.?
Regarding lossless compression versus uncompress, if at the end the picture we sell is converted to JPEG format, should the conversion from RAW to JPEG be from lossless compressed RAW to JPEG or uncompressed RAW to JPEG ?
Now a key question for me : Converting from RAW to JPEG, what would be the best setting to minimize the compression and maximise the quality of the JPEG photo ?

The only difference in lossless compression versus uncompressed, is the speed from camera saving to the flash card and loading from card to computer. Compression and uncompressing take a bit more time and may not even be noticeable. From lossless compression versus uncompressed, to JPG, makes no difference what-so-ever since the data is already uncompressed before converting to JPG.

KenL

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OK for JPG pictures saved in the camera, but what about RAW. Is uncompressed taking more time to save than lossless compressed ?

It will always take more time for the processor to compress before sending data to a card. How mush? Of course it depends on card speed. On fast cards it may not be noticeable. I haven't tested because I don't care. I want purity so I use uncompressed. It hasn't bothered me on hi-speed cards. Test it yourself and let us know which you prefer.

KenL

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Thom Hogan has an interesting web page on this topic here: http://www.bythom.com/qadraw.htm

The bottom line for me is: More bits are better, lossless compression doesn't hurt much, and keep your RAW conversion software up to date.

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