I want to address a common misconception. Some people shooting video or JPG with dSLRs claim:

If you are going to shoot JPG or video on a DSLR then shoot in Adobe RGB 98 because it is a wider color space. You can always switch to sRGB later and it will throw out the extra data

This is, quite frankly, WRONG. Being a “wider” colorspace does not make it a “better” colorspace. Especially when dealing with 8 bit file formats.

There is NO EXTRA DATA in Adobe RGB relative to sRGB – this is a common misconception. The “amount” of data in a file is related to the bit depth and not the color profile.

An 8-bit sRGB file and an 8-bit Adobe RGB file both have the SAME amount of data. The only difference is that in Adobe RGB, the distance between colors is greater. And because of the limited interpolation of 8 bit data, this means the delta E errors are larger in Adobe RGB than in sRGB.

The end result is that if you shoot in 8-bit in Adobe RGB and then convert to sRGB you will be introducing greater delta-E errors into the image.

And here’s the thing: as long as you are not clipping color channels in sRGB, then there is no benefit to using a larger color space like Adobe RGB, regardless of bit depth. You want to use larger colorspaces when you are clipping (running out of “room”) in the colorspace you are working in.

If you shoot 8 bit in Adobe RGB then convert, you are not “throwing away extra data”, but you are damaging color accuracy. 

Gamma encoded sRGB and Rec709 were developed to work well with 8 bit files. Adobe RGB less so because it has the primary colors set a larger distance apart, and thus introducing greater delta E errors. ProPhoto is USELESS in 8 bit, and should be used only with 16 bit or greater file types. IMO, Adobe RGB should also only be used with 16 bit or greater file types.

WHEN RECORDING VIDEO IN A DSLR:

Use sRGB. sRGB matches the primaries in Rec709, and Rec709 is the standard for HD.

If you have specific shots where you are clipping specific color channels, and you are going to record out to actual film or go to DCI/P3, then Adobe RGB *may* be an appropriate choice.

But Adobe RGB is the wrong choice for the vast majority of video work, and especially video that is in 8-bit, and more especially for video that is heavily compressed 420 or 422 and not 444. (dSLRs are typcially 420).

The reality is that if you want to be working in a “wide gamut” space, then shooting video on a dSLR is not a good choice to begin with. You want a camera that can shoot at 10 bit minimum, and either to RAW or LOG encoded files such as RED or ALEXA.

To get the best results in a dSLR, use the smallest colorspace that fully encloses your subject, control scene contrast, and keep the image within the limited latitude of 8 bit video.

FINAL NOTE:

If you don’t have a wide gamut monitor that can cover the Adobe RGB gamut, then you will not be able to see that additional color information accurately, either.

Most monitors are sRGB (or even smaller gamut). HD monitors are set for Rec709, which uses the same primaries as sRGB. When you watch a BluRay on your nifty HDTV, you are watching Rec709. sRGB is the *same size* – it uses the same primaries. (only the gamma curve is different).

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