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John Willard
01-02-2008, 09:38 AM
When I work on a 16bit, TIFF file in PS I want to reduce the file size for storage but am not sure of the best way to compress a 16 bit file and store it as an 8 bit file. Please lead me through the process in detail (step by step what items in what windows to fill in or check). Thanks:confused:

Fabs Forns
01-02-2008, 11:55 AM
Hi John,

Not sure why you would want to save an 8 bit file vs 16 bit? Storage is not that expensive nowadays.

Anyway, the way I do it when I need to go 8 bit for instance to make some filters effects work, is go to Image>Mode>8 bits

Hope this hepls!

Robert Amoruso
01-02-2008, 01:57 PM
Welcome John.

I don't see much of a reason to do this as the savings in size is not great in a flattened file. If you are still saving in TIFF format, it does not compress the file. Going from 16-bit to 8-bit for some PS effects as Fabiola noted is required, but your best quality will be maintained leaving the file in 16-bit and saving it as a TIFF

Now if you want to create a JPG, it will make sense to change it to 8-bit as part of that process. If you need to know how to do that, let me know here and I will post the workflow.

Storage is very inexpensive nowadays, I would recommend not reducing a 16-bit file to 8-bit. However, if you wish to do it, go to the FIle menu and Image>Mode>8 bits as Fabs mentioned.

Bill McCrystyn
01-17-2008, 02:02 PM
You know, I have been round and round with my friend on this. I guess all the "pros" shoot, capture, take, create, whatever their pictures, err images in RAW mode, then save Jpegs for the web and 16 bit Tiffs to edit and print in addtion to their RAW files.

If you want 8 bit Tiff or Jpeg from RAW just save it that way coming from the RAW mode. Further, you may compress the Tiff in the LZW mode with little to no effect on image quality and large effects on file size. I don't think storage is the issue. Three seperate files, one of which does you almost, practically speaking, no good, that being the 16 bit file, is what is questionable.

You see the problem is, correct me if I'm wrong, that as soon as you convert to Jpeg for the web or print your image you have just lost ALL that extra infomation, so what's the point? In my opinion save computer space, differant programs for differant cameras RAW versions, time consuming workflow, speed up and extend your motor-drive range, tax your card space way less and shoot LJpeg. If you can see the differance between a print made from a 8 bit Tiff and one made with a 16 (that's really, what 12 bit) you have way better eyes than the average Eagle. At that point you may have some very small changes in the shadow areas that more than likely would be inconsequential anyway.

I know this apparently flies in the face of conventinal wisdom so blast me if you want but I personally can not see the differance and never have met anyone who could. On screen - yes, in print - no. From my standpoint, the question is, why would you want to shoot and save RAW files unless your working on assignment for a magazine? Mr O'Toole makes this very same kind of argument (practicality) in favor of sRGB considering end use.