Noise in 8-bit TIFs

[pkd14u]

Help please!

I shoot Raw and would like to be able to save my photos in 8-bit TIF format. The problem is that when I save that way, I end up with a bunch of introduced noise in the photos. If I save 16-bit the files are huge (126+ mb per photo), but they look good. Does anyone know a good way around this? Am I just doing something stupid? It doesn't matter if I'm saving in Photoshop or in Lightroom (both are latest versions).

Can anyone help a girl out? I'm at my wit's end and need to have a good workflow that will give me good results!

Thanks in advance.

[SLWRTHNU]

are you using any kind of compression? I just played around in Photoshop CS5 and can't find a way to change from 8-bit to 16-bit so I don't have a way to see if I can reproduce the issue. You could always try saving PNG and see if that helps any?

[pkd14u]

I can save PNG just fine, but that's not what I need to do. JPGs look fine, as do 16-bit TIFs, but 8-bit TIFs are noisy. I can also reduce the size of my images and they look just fine if I save 16-bit, but as soon as I try 8-bit, noise is introduced. There is no other compression being added to the files.

Thanks for trying to help.

[rpandrada]

I think it is logical that the quality of the image will be degraded as you decrease the color depth, by changing from 16 to 8 bit. Then you may see a little more noise and posterization. However, I believe that the difference should not be too noticeable, unless you are doing something else.

Are you processing the pictures before saving them to 8-bit TIFs;? It may always be better to do processing in 16-bit and then saving it to 8-bit.

Pablo

[jpowers]

You should ideally not see any change from 16-bit to 8-bit. After all, the 16-bit image is being displayed on a monitor with 8-bit color depth.

More to the point, though, if saving in to some file format is producing poorer results than JPEG, something is going wrong. (GIF doesn't count.)