Monday, May 16, 2011


Discovered something annoying about Lightroom.

When exporting to JPG the saturation of the original isn't the same. The JPG looks slightly under saturated compared to the original in Lightroom.

After some Googling this seems to be a well known problem, with a lot of people pointing to color spaces (sRGB versus ProPhotoRGB) or monitor profiles.

Now, despite the fact that profiles and color spaces surely can have their effect (depending on the program you view the JPG in) I don't think that's the whole story.

I have my doubts, because if it's ProPhotoRGB versus sRGB, why is it that an exported TIFF in ProPhotoRGB (doesn't matter with what settings, 8/16 bit, compressed or non-compressed) with Lightroom, on a monitor without a profile, also looses saturation when viewed in Lightroom?

When I compare the original RAW with the exported TIFF there's a difference, mainly in saturation.

Surely an uncompressed 16 bit TIFF should look exactly the same when exported with the same color space as the original, when viewed in the same program that supposedly uses ProPhotoRGB as working color space? But it doesn't... so what am I missing here?

I must add though that the assumption that Lightroom uses ProPhotoRGB is mainly taken by hear say. It's claimed by a lot of people on the Internet, but I think the first step should be to confirm it myself through some info from Adobe.

Then I'll be doing some more testing, since it seems that there's also a difference between RAW files. My older Canon 40D files seem to be less affected by this problem than my 5DII files. But perhaps it's me not noticing this sooner, because it's not something you would expect. Or perhaps it requires certain tweaks in Lightroom that I only applied to my recent photos.

I also want to have a good look at the DNG files. Perhaps this is more specific to the RAW conversion of Canon files.

I have a vague idea that this problem has 'something' to do with the 'blacks' slider and less with color spaces (or perhaps the mysterious black point moving around, thus a combination of converting color spaces with a cranked up 'blacks' slider), but I'll be testing that a bit more.

Yes dear reader, when it comes to the digital world, almost nothing is simple. These manufacturers don't seem to be able to come up with a lot of definite standards. Try browsing through your PhotoShop's 'color settings' and you'll know what I mean. It's a mess. No sane person would actually want to know how it works, but sometimes you have to... so, reluctantly I'm now diving into the fascinating world of color spaces...

Some suggest you should export as TIFF, then do the main work in PhotoShop, but that adds a tremendous amount of work to the whole work flow and it sort of defeats the purpose of all those handy sliders in Lightroom. If it's really color space, I wonder why Lightroom can't be switched to sRGB.

Here's an example, created in a somewhat unorthodox way: they are shots, snipped directly from the screen. That does seem to preserve the original saturation.

The first is from the original as viewed in the Lightroom Develop module. The second is from an exported 16-bit TIFF in ProPhotoRGB also viewed in the Develop module.

The difference is what I see in Lightroom.

Kinda ironic that I can see my saturated example as JPG, but that I have to copy/paste it directly from my screen. Come on Adobe...

I mean, how is it possible that a simple cheap screen grabber gives me the JPG I expect to see, but the export from a sophisticated piece of software doesn't come close (well, relatively speaking)?

I don't have an explanation.

Obviously, with the JPG export the ProPhotoRGB to sRGB conversion doesn't help, which might explain the stronger effect with the JPG compared to the TIFF, but I first like to figure out why the TIFF looses color too and if I'm missing something here (apart from my saturation!)...

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