Gray mode and dot gain

I have a number of black and white negatives which I'm scanning with my Nikon Coolscan III. I have to do this on another machine (not a Mac or PC) as the scanner interface is SCSI. I'm scanning them as gray scale images and saving as TIFFs.

When I look at the TIFF info on the other machine it says they're gray scale. When I load them into PE2 on the Mac it gives them an Untagged RGB profile and thinks they're colour images (which I find strange). If I then convert to grayscale PE2 gives them a 'Dot Gain 20%' profile.

Can someone explain to me the concept of 'Dot Gain' and whether it is better to leave the images as colour (with Adobe RGB profile attached) or grayscale? I haven't tried printing any of them yet; I'd like to check this out first to reduce waste of expensive paper. The printer is an Epson Photo 950 attached to an iBook running OS X 10.1.5.

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Pete
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*** Email is pete -at- dawnsun -dot- net

Peter,

It is better in Elements to keep the RGB color mode, even if using gray scale colors, as RGB is the ONLY color mode where you get all functions and filters. Other color modes are limiting. Your gray scale color should NOT be effected by being in RGB mode.

Bob

In article
wrote:

Peter,

It is better in Elements to keep the RGB color mode, even if using gray scale colors, as RGB is the ONLY color mode where you get all functions and filters. Other color modes are limiting. Your gray scale color should NOT be effected by being in RGB mode.

Thanks, Bob.

What do I do when printing (Epson 950)? Should I set the printer to 'black only' or leave it as colour?

Try printing in "black" (shades of gray, of course) only. Some printers will try to apply tones of color to accomplish black. Or, if you are finished with all workings of the image, you can also do a Save As in Shades of Gray color mode only to another filename and use that for printing (still Black mode only). Keep the original in RGB for archival purposes.

Bob