Here's the situation. I created a large document, laid in some text with cool effects then created a copy and flattened it. The effects were still there but noticably different. I know merge down or merge visible can cause this but flatten was supposed to keep everything looking the same.

Well, in an attempt to demonstrate this problem in an uploaded file, I decided to do a screen shot of the two versions of text so you could see the difference between flattened and fully layered. To do this I zoomed in on the text on both images to 200% and flattened the copy. No changes took place. This was confusing since the changes were clearly noitceable when I did this before. I don't know what made me try it again at a view of about 50%, but there it was. The changes were there again. Now I started playing around with the zoom tool and found out the changes only occured in the 50% or lower view range.
If I hadn't tried to show this to you for some possible explainations, I would have gone crazy trying to figure out why my text was changing when nothing else was. Anyone know why this happens?

At any rate for future reference, if you notice some funny things happening when you flatten an image viewed less than 100% keep this situation in mind.
DJ

DJ:

This is a known phenomenon that comes up every once in a while as a question / issue on the Photoshop forum over at Adobe.com. I've never seen a real technical reason offered for the difference between "before" and "after" flattening (occurs when merging layers, too).

The Adobe engineer types just say the only truly accurate way to assess an image is to view it at 100% (actual pixels). What you see at 100% is what you'll get flattened.

~Danny~

Thanks Danny for your input.

I've seen it happen with certain filters such as a texture filter but the change occured when just viewed at different magnifications. This really threw me for a loop because it looked just fine at any magnification until I flattened it.
When I finally figured out it was a view size situation, I could deal with it but I thought it would make a good thread subject to keep others from getting frustrated as I did.
DJ

Without reading up on it, the most obvious answer that comes to mind is (first a question) Does it happen when you are merging layers? If so the main culprit will be layer masks and associated layer effects. Create a blank layer below and then merge into the blank layer, there is a simpler method, that escapes me for now......:( (it may have something to do with not using merge down but merge all, time has withered my knowledge;))

That was the first thing I thought too but it was on a Flatten Image this occured. I even tried the others and the same thing happened. You wouldn't believe how many ways I tried flattening that image to no avail. I actually turns out not to be a physical thing just a visual one. When I flattened at 66% or higher the problem disappeared entirely.
DJ