When you apply transparency anywhere on the page all objects on the page are displayed via the page's Transparency Blend space. So if the photo is grayscale and the blend space is CMYK, it previews as if it is on the CMYK black plate via the document CMYK profile. Same thing happens if you turn on Overprint preview. If the document CMYK profile is correct the overprint preview is more accurate.
Thanks so much.
This is what happened. I had a grayscle photo on the page. It apeared dark. Added box with effect on it. Photo appeared light. Now with View> overprint preview checked. Grayscale photo does not appear dark when placed and does not change when effect added to other objects.
So basicly with overprint preview on. I am seeing a more accurate representation of how things will print? Correct?
I am seeing a more accurate representation of how things will print?
Right, assuming you have the correct CMYK press profile assigned to the document. With overprint off and no transparency the preview of a grayscale is sGray or the same as the Gamma 2.2 Gray working space in Photoshop.