Look at your document at 100% zoom, specifically.
Now do you see a difference between the layered and merged versions? You shouldn't.
For speed Photoshop takes some shortcuts that approximate your results when you're zoomed out, when it comes to combining layers and rendering styles. Only at 100% zoom can you be sure of what you're going to get.
Post a screenshot showing before and after merging layers if you'd like. This will ensure we're talking about the same thing.
I see what you mean, however it does not apply to this case. Looking at it at 100% makes it appear a little better, but from a distance the change is still apperent. With the added layers the text I am using appears slightly bolder, making the background less, therefore making the image lighter. However the main problem is still there, even at 100%. The thing is, I dont understand why when I merge everything just disapears, there is obvious change with the added layers but yet when I merge, nothing, it all gets thrown away.
It is slightly diffucult to tell, but the most noticable spot is under the lips, so the bottom portion. On the left is a single layer with adjustments, while the right is the same layer with duplicates underneath. The solid background is on a different layer all together. What this does it thicken up the text just a bit to make the image more apperent and better readability. (Just so you know if you read the actual text, it is a college project for a line of snowboards for my type class)
Edit: http://people.ysu.edu/~jtpenezich/other/Untitled-1.jpg that is a link to the image on my server, probably a bit easier to use.
Edit 2: This also persists in any color mode/profile. I think the pictures taken were RGB, because when converted to CMYK or converted during the PDF process everything muddies down in color.
You've shown the difference between having one or two groups visible, but I don't see an image showing a merged result that looks different than either of those cases.
If you'd like, duplicate the document, crop a small part of it, then save as a PSD file and post the PSD file on your server. I'll be happy to see if I see a difference before and after merging.
Uploaded here: http://people.ysu.edu/~jtpenezich/other/
The reason I showed it the way I did, which would of been easier the way you described, was because it is basically the same. I croped a portion for you to check out, and tried the merge and flattening myself, and it still does change, so maybe you can find out the reason.
Either I don't understand what you're trying to do or I cannot reproduce the problem.
Note the following two screen grabs:
Both layers separate and visible:
The two grouped layers merged together. No difference in appearance from the above:
Am I misinterpreting what it is you're merging when you're seeing the problem.
By the way, the above is grabbed from Photoshop CS6. I tried it in Photoshop CS5 as well and the results were the same.
I see what you mean. I think I was just failing somewhere along the lines. The 100% issue seems to be the correct solution. However I guess I should as why 100% in the psd and pdf forms are so different. At 100% the psd is much larger in scale, and the pdf form seems to be a little darker, but if I zoom past the 100% it seems to be the same around 300% zoom.
Thanks in advance, not exactly sure where I was getting screwed up, but I never knew about the 100% issue, which seemed to be the majority of the problems I was having last night.
Image of what I mean:
At 100% the psd is much larger in scale,
It isn't. You're forgetting about document size vs. resolution (DPI/ PPI) vs. how Acrobat calculates the preview whereas PS displays each pixel at 100%.
I was just about to suggest that. Sorry it's been a long day. So I figure all is right in the world, thanks for all the help guys.