Color Space Question

Plato

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Can others edit my Photos
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To put this in perspective, I'm an amateur and nearly all of my shots are for personal enjoyment or for family and friends. Be that as it may, my goal is to always do the best that I'm able.

There seems to be no doubt that 16-bit RGB color space far exceeds the quality of 8-bit. Also, Adobe recommends ProPhoto RGB over sRGB and Adobe RGB. I'm just learning RAW and I bring the RAW files into either Lightroom-2 or Nikon's Capture NX2 (on a Mac). I'm still uncertain which RAW processor that I prefer but I'm leaning toward LR because of Topaz compatibility. When I finish in LR (or NX2), I export either a TIFF for further work in PSE-8 and eventually create a JPG or, if I'm finished with the image, I export a JPG directly from LR. In either case, I use iPhoto to catalog all finished products (JPGs) as it allows me to interface with dot-Mac blindfolded.

The Topaz plug-ins work from inside LR, PSE and iPhoto (but not NX2). That gives me another advantage in that I can bring my wife's Casio shots directly into iPhoto and still make them look as good as is possible.

Now to the question after the long-winded background description...
For those photos that I intend to give to friends and family, will the 16-bit color space and/or the ProPhoto RGB color space screw them up? What should I do (and how do I do it) to change the JPG files before distributing them while retaining as much quality as is possible?
 
Well you can't save a 16-bit file as a JPEG, you have to convert it to 8-bit first. Do all your editing, and as the last step, flatten the image and convert it to 8-bit. Then save as a JPEG. I would also keep it in sRGB if you're going to give them to others. Most monitors are calibrated to sRGB, plus that's what the Web runs on. And it keeps things simple. ;)

Personally I shoot RAW, edit in 16-bit sRGB, and save it as a PSD file, with layers. That way I can go back later and create additional JPEGs, re-edit, or whatever. If I'm using it on the Internet (Web, email), I flatten the image, convert it to 8-bit, and save as a JPEG, resizing as appropriate. For prints you'll want the full-res JPEG.
 
Quite a few people and applications they use will have difficulty with 16-bit files. Also, I think it's wise to tag images with an sRGB profile when distributing them for e-mail or for the web. Macintosh browsers are color-aware and will recognize and display the right color profiles, but the majority of Windows systems will not, and so your photos might look very ugly and dull. So, tag the images you export to JPEG as sRGB and you can rest assured that Windows users will see your photos the way they were meant to be seen.

SOme automated printing systems installed in drug stores and big box stores "expect" that, since most people use Windows, that the color profile should be considered to be sRGB by default, so once again, tag those images sRGB when you distribute them. We all know Adobe RGB and ProPhoto RGB have wider gamut than sRGB, but the prevalence of Windoze is proof that better doesn't necessarily mean more widely-distributed, so once again another inferior system, sRGB, has become the norm.
 
Well you can't save a 16-bit file as a JPEG, you have to convert it to 8-bit first. Do all your editing, and as the last step, flatten the image and convert it to 8-bit. Then save as a JPEG. I would also keep it in sRGB if you're going to give them to others. Most monitors are calibrated to sRGB, plus that's what the Web runs on. And it keeps things simple. ;)

Personally I shoot RAW, edit in 16-bit sRGB, and save it as a PSD file, with layers. That way I can go back later and create additional JPEGs, re-edit, or whatever. If I'm using it on the Internet (Web, email), I flatten the image, convert it to 8-bit, and save as a JPEG, resizing as appropriate. For prints you'll want the full-res JPEG.

Thanks. I haven't consciously converted to 8-bit inside PSE but, based on your comment, saving as JPG automatically drops it down to 8-bits.

I'm hoping to stick with ProPhoto RGB because of Adobe's recommendation so I'll have to convert from inside PSE before I save as JPG. I had originally intended to work with PSD files but, again, Adobe recommended TIFF over PSD! I forget the reason (I'm not home right now) but I believe that it had something to do with flexibility.
 
Quite a few people and applications they use will have difficulty with 16-bit files. Also, I think it's wise to tag images with an sRGB profile when distributing them for e-mail or for the web. Macintosh browsers are color-aware and will recognize and display the right color profiles, but the majority of Windows systems will not, and so your photos might look very ugly and dull. So, tag the images you export to JPEG as sRGB and you can rest assured that Windows users will see your photos the way they were meant to be seen.

SOme automated printing systems installed in drug stores and big box stores "expect" that, since most people use Windows, that the color profile should be considered to be sRGB by default, so once again, tag those images sRGB when you distribute them. We all know Adobe RGB and ProPhoto RGB have wider gamut than sRGB, but the prevalence of Windoze is proof that better doesn't necessarily mean more widely-distributed, so once again another inferior system, sRGB, has become the norm.

Thanks. I pretty much had decided to convert to sRGB for distribution but your post and Dennis' post seem to contradict each other with regard to bit levels. Do 16-bit JPGs exist?

Edit (another question)...
If I know ahead of time that my end result will be sRGB JPG, is there any benefit to using ProPhoto RGB in Lightroom and PSE and then converting to sRGB or should I use sRGB from start to finish? Similarly, should I stay with 8-bit from start to finish?
 
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I'm hoping to stick with ProPhoto RGB because of Adobe's recommendation so I'll have to convert from inside PSE before I save as JPG. I had originally intended to work with PSD files but, again, Adobe recommended TIFF over PSD! I forget the reason (I'm not home right now) but I believe that it had something to do with flexibility.

Thanks for this post. It prompted me to search around for PSD vs. TIFF information and you're right, TIFF is actually recommended over PSD. Here's one of the links I found:
Ted Dillard: TIFF vs PSD- Schewe (via Luminous Landscape)

I guess I should switch to TIFF!

Thanks. I pretty much had decided to convert to sRGB for distribution but your post and Dennis' post seem to contradict each other with regard to bit levels. Do 16-bit JPGs exist?

There is something called JPEG 2000 that I believe supports 16-bit images, but I don't think it's widely supported. You might want to search around for info on that, not to sure myself. But regular JPEGs do not support 16-bit images.

Edit (another question)...
If I know ahead of time that my end result will be sRGB JPG, is there any benefit to using ProPhoto RGB in Lightroom and PSE and then converting to sRGB or should I use sRGB from start to finish? Similarly, should I stay with 8-bit from start to finish?

That I am not sure about either. We need someone like Garbz or KMH to provide input here, hehe. Although if I had to guess, any additional gamut gained by editing in ProPhoto or AdobeRGB is probably lost on conversion to sRGB. It's probably the same with 8-bit vs. 16-bit, but I edit in 16-bit and convert to 8-bit at the end anyway (for Web stuff). It'd be interesting to know this for sure as I may just be wasting hard drive space with 16-bit images. They can be huge.
 
Plato asked, "If I know ahead of time that my end result will be sRGB JPG, is there any benefit to using ProPhoto RGB in Lightroom and PSE and then converting to sRGB or should I use sRGB from start to finish? Similarly, should I stay with 8-bit from start to finish?"

Well, I have no idea about your workflow or how you process images; some actions in Photoshop cannot be performed on 16-bit files,and require that the image be converted to 8-bit to perform. I can only tell you that "my" preference is to convert my best images from RAW to a 16-bit .PSD file and perform as much work as I can at the 16-bit level, and then when the images look good, I will save the images as full 16-bit .PSD files.

My belief is that .TIF files (which can be .TIFF files with two Fs on the Mac platform) are more universally readable by more applications than .PSD files are. As far as 16-bit JPEGs and the JPEG-2000 specification--I have no idea. I would keep my images in the ProPhoto color space as long as possible; now that disk space is cheap and batch processing is fast,sure,and easy, it's possible to use an application such as Automator (for the Macintosh) to design automated workflows that will open a file, change the profile, and perform a whole host of other actions to create web-optimized or print-optimized files from your "Master" or "Retouched-Intermediate" files.

Check out this for Automator actions Photoshop Automator Actions v3.7 : Complete Digital Photography

Automator is a built-in Macintosh system application not many people talk much about....you might have fun with it!



Questions about how best to keep digital files are a lot like discussions about drinking glasses in the cupboard: stored rim up, or rim down? Or toilet paper--coming over the front side of the roll, or from the back side of the roll?
 
Thanks for this post. It prompted me to search around for PSD vs. TIFF information and you're right, TIFF is actually recommended over PSD. Here's one of the links I found:
Ted Dillard: TIFF vs PSD- Schewe (via Luminous Landscape)

I guess I should switch to TIFF!

Adobe made that recommendation right in the Lightroom-2 preferences pane!

There is something called JPEG 2000 that I believe supports 16-bit images, but I don't think it's widely supported. You might want to search around for info on that, not to sure myself. But regular JPEGs do not support 16-bit images.

As far as I can determine you're probably correct about JPEG-2000. However, my understanding is that the major reason for its existence is lossless compression. Unfortunately, there are only three persons in the entire world that use it and none of them are in my social circle so I'd be opening up another can of worms. The fact that regular JPEG does not support 16-bit is the info that I was looking for.

That I am not sure about either. We need someone like Garbz or KMH to provide input here, hehe. Although if I had to guess, any additional gamut gained by editing in ProPhoto or AdobeRGB is probably lost on conversion to sRGB. It's probably the same with 8-bit vs. 16-bit, but I edit in 16-bit and convert to 8-bit at the end anyway (for Web stuff). It'd be interesting to know this for sure as I may just be wasting hard drive space with 16-bit images. They can be huge.

My gut feel is that you're 100% correct. It does not make sense to work in 16-bit and/or ProPhoto RGB if it will all be changed in the end product. However, I have a late-model Mac and I can do everything in 16-bit/ProPhoto, including printing. I have not yet confirmed that my printer can handle it but, if it can, I'll use those settings for my prints and then dumb down the files for others.
 
Derrel,

I was responding to Dennis while you were responding to me. Look at my comments to him.

1) I checked out the Automator link that you provided. Unfortunately, I don't have PS. I have PSE. Also, this is a bad time for me to mess with it. I'm fighting several software packages, all of which insist on cataloging my photos for me. I'm ending up with copies all over and I'm getting really screwed up.

2) I've pretty much convinced myself that it's foolish for me to use 16-bit ProPhoto unless I can confirm that my printer can handle it. If it cannot, it makes sense to immediately export as 8-bit sRGB. There's something to be said for consistency. If anything changes in the future, I'll always have the RAW files and I can start all over again.

Thanks again for your help.
 

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