I have been trying to stack about 162 images for star trails, and everytime I try to flatten the image for export it washes out and introduces strange lines throughout the entire image. I edited every image in lightroom then loaded them into photoshop, and all of the layers are set to the lighten blend mode except the bottom one. I have tried using ctrl-shift-alt-e to flatten as well as just regularly flattening the image, and I have provided screenshots of the before and after. Any help would be greatly appreciated. Thanks!
Adobe Community Professional, Apr 21, 2020Apr 21, 2020
davescm • Adobe Community Professional, Apr 21, 2020Apr 21, 2020
Compare before and after at 100% zoom. Zoomed out, the composite preview is blended using 8 bit previews rather than the actual 16 bit image layers. This is done for speed. At 100% zoom the full 16 bit image layers are blended and should match the flattened version at 100% zoom Dave
Compare before and after at 100% zoom. Zoomed out, the composite preview is blended using 8 bit previews rather than the actual 16 bit image layers. This is done for speed. At 100% zoom the full 16 bit image layers are blended and should match the flattened version at 100% zoom
I'm having a similar problem, though it's manifesting a bit differently. I'm stacking 69 frames in PS (edited in LR separately) using the Lighten blend mode (all except the bottom layer, which has normal blend), then changing the opacity of each individual layer incrementally (0 to 100%) to create more refined trailing stars. The image I create on screen looks how I'd like it to, but, when I try to flatten/merge layers/merge visible, the whole thing washes out and creates a weird crosshatch-type pattern across the image. It almost looks like the transparency of the canvas showing through, but that shouldn't be happening since I have a bottom layer set to 100% opacity.
I've watched/read several other photographers use this method and they don't seem to have any issues, so I'm really confused why it's happening to me. I first thought I messed up the opacity, but it turns out that it's related to the Lighten blend mode, because even if I choose Lighten and leave the opacity at 100% across all layers, the same pattern appears when flattening. The original images don't have this pattern before blending.
I've attached images at 100% and 17% zoom for reference. Would really appreciate any help because I'm banging my head against the wall trying to figure out why this is happening! What am I doing wrong?? Thank you!