Ah, what I ment about there being no difference is one isn't better than the other in terms of image quality. They just merge layers. It's more of how you do it.
Quality shouldn't matter....just file size. For every layer you have your file size is bigger. IE: 2mb without. with 1 layer=4mb, 2 layers=6mb, etc, etc.
and while it may be obvious to some it took me a while to realize, you have to be on a currently visible layer to merge visible...drove me nuts wondering why it wouldn't do it.
Um, one last question... what is an invisible or non-visible layer? and what are they used for? thanks!
1 - On the layer palette you can see a little 'eye' icon. When it is turned on then that layer is visible. But sometimes you want to see what the image would look like without a particular step in your processing.
2 - So you turn the layer off by clicking on the 'eye' icon of the specific layer.