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etherial
05-09-2009, 5:54pm
Hi, now I know 16bit would have to be better, but I'm wondering your thoughts on this.

I am using Camera Raw 4.5 and PSE7 to edit my files. When I open the raw file I can select 8 or 16 bit color depth in Camera Raw. I can't really tell a difference. When I then get to PSE7 step if I want to do any editing (ie spot healing or the like) I have to convert to 8bit, and also when I go to save as JPEG, I must convert to 8 bit first.

Now I can't tell a difference, but there must be a drop in the available range of colors. I'd be interested to know what those of you with more eye for detail and more experience than me think of the issue? Is it not a problem worth worrying about, or is this a reason to step up to a better software package?

Any thoughts?

Kym
05-09-2009, 5:56pm
I keep all my work in 16 bits (RAW or PSD in Lightroom) - you can always convert down but when you convert up you have a loss.

I only convert to 8bit/JPEG when publishing.

ricktas
05-09-2009, 6:08pm
JPG has to be 8 bit, that is what JPG is, an 8-bit format.

The difference on most monitors is negligible, but 8bit photos have an maximum of 256 levels of brightness for each colour, where 16 bits is over 60,000. Interestingly most DSLR capture somewhere in between, usually around 12-14 bits.

So, do you keep them as 16bit? Depends. Certainly in future as screen and print technology improves we will see results that outdo what 8 bit offers, whether the human eye can perceive differences at the 16 bit level is debatable. If you take two pixels at 16 bit and adjust one of them by one single step, the human eye probably would not be able to detect that variance. It could be argued that saving in 16 bit is 'future proofing or future preparing' your photos. Whether you save as 8bit or 16bit is entirely up to you.

TOM
05-09-2009, 7:11pm
just to reinforce what has been said above, it is best to work in 16 bit and output at 8 bit. only high end dslr's can capture in 16bit but I'm not sure if the benefits are there. even with cameras like a nikon d3, capturing in 14 bits will yield little, if any improvement, when it comes to the final print. if you are working closely with a lab, then you will need to get profiles from them and therefore use whichever colour standard they are. if you have a go to woe workflow 'in house;, then working in sRGB is probably ideal. even sRGB captures more information than you can print, so working with a standard that requires the least amount of compression for output will usually work best. Adobe 1998 has a much larger gamut, but it is all wasted at the end of the day.

etherial
05-09-2009, 7:21pm
Thanks Guys, some interesting points. In Camera Raw it has an option for 16 bit or 8, I guess I should use 16 here. If I select 8 I don't then have to convert the color depth once in PSE7. Not sure if it makes a difference when I convert, as I say I can't see a difference but I'm a novice.

Also I notice when I save my files as a JPEG on PSE7 it changes the color space in the EXIF from sRGB to AdobeRGB. Anyone see this as an issue, again I can't see the difference.

End of the day at least I still have the raw to fall back on.

wideangle
05-09-2009, 7:28pm
End of the day at least I still have the raw to fall back on.

Don't rely on any medium - even RAW files are not 'fool=proof' The RAW format isn't as you would know all the same. Each manufacturer has their own RAW program/output, and there has been much debate as to what happens when the format/camera is no longer supported? Adobe has tried to allivec such problems by attempting to standardise the format with its free DNG format.

ricktas
05-09-2009, 8:25pm
Find the settings in PSE to retain JPG in sRGB. If it is converting them to AdobeRGB and you are uploading to the web, anyone without a colourspace aware internet browser (latest versions) will see a washed out version of your photo. AdobeRGB although a bigger colourspace has a tendency to look 'flat' when viewed over the net in a non colourspace aware browser

etherial
05-09-2009, 8:35pm
Find the settings in PSE to retain JPG in sRGB. If it is converting them to AdobeRGB and you are uploading to the web, anyone without a colourspace aware internet browser (latest versions) will see a washed out version of your photo. AdobeRGB although a bigger colourspace has a tendency to look 'flat' when viewed over the net in a non colourspace aware browser

Thats what I was worried about...seems the spot to change it is in the icc profile when I save it. If I tick the box it stays sRGB otherwise it changes it to adobe. I thought I had all that sussed...oh well live and learn.