URGENT : layer effects not rendering correctly

[Ann_Johnson4824]

I'm in a real jam. I have a large format graphic file, 363" x 45" at 300 ppi.

It looks gorgous as a PSB, but when I go to flatten the file, the layer effects (bevels, glow, shadows, etc) are not rendering properly. I even tried to just copy merged and paste and it's not even doing that without changing how the effects look. HELP! Deadline today. FIrst pic is how it should look and looks when it's layered PSB. Second pic is how it looks when I merge, flatten, copy merged, make smart object of whole thing. I've tried all my tricks. I'm baffled.

[davescm · Accepted solution]

Zoom in and check whether there is a change before and after flattening at 100% zoom.

If that looks the same, then this isn't a bug, but an effect of the way Photoshop renders previews when zoomed out. When previewing at less than 100%, Photoshop does not blend every individual pixel on every layer, but works with groups of pixels in caches. Most of teh time there is little visible impact of this, but with certain images it can alter the preview. Blending should always be chacked at 100% as that does show teh impact of blending individual pixels and will match the flattened image.

Dave

[Ann_Johnson4824]

Thanks for your reply. I can confirm at 100% size the rendering is super smooth. Until I try to flatten, merge in any number of ways.

[davescm]

I think you may have missed my point. This is not about just looking at the image at 100%.

The comparison at 100% zoom, where 1 image pixel is mapped onto 1 screen pixel, is before and after flattening. At that zoom level before and after flattening should look identical. 

However, if zoomed out, before and after flattening will look different. How different depends on image content and blending effects. On some image content the difference is barely visible, on others the difference can be huge. That is the way preview views are built in Photoshop using image caches.

Dave

[Ann_Johnson4824]

My appologies, you're right!!! When I zoom into 100% it's EXACTLY what it looked like rending it out. But yes, the preview was really off. Thank you SOOOO MUCH. You saved the day!

[davescm]

You're welcome - you are not the first to be caught out by that preview 'artifact'.

Dave