I hope some of you can help me. I am trying to learn focus stacking and exposure bracketing. One important photoshop tool is to align different pictures when set up in layers. I have used different ways to achieve this, but photoshop is not able to align the pictures perfectly which I find odd. The problem must be with me , I suppose. My setup is either nikon Z6 or Nikon D800 mounted on a tripod with the lens stabilisation turned off. I then take several exposures with different exposure or focus point (with some focus breething which is impossible to avoid). I make sure to group the photos so that I do not mix different focal length and so forth. When I import the pictures into photoshop to make magic , I have tried throu LR and make it open the pictures in different layers. I have also opened the pictures with ACR and arranged them in different layers in photoshop. When I auto align the layers they always seems some pixels off (from 5 to 10). The same happenes when I import directly in photoshop script stack (did I write that correctly ?) . From time to time the alignment is perfect, but most of the time not. The pictures are typically ordinary landscape pictures, where there are a lot of detail, and most pixels should be almost perfect aligned to begin with ( pre alignment) . I do not use smart objects (I am not smart enough). So I think I follow the tutorials, but my photoshop (latest edition subscription) does not deliver. The tutorials I watch arrange the picture in layers, and then choose auto-align and voila , it works. Not with me though. When clicking one layer on and off afterwards, with som magnification, you clearly see it "jumping" slightly , most often to one side, seldom upp and down. So, please tell me what I am doing wrong ?? I use a windows 11 laptop (problem present when I used windows 10), the CPU, GPU , SSD and RAM is sufficient for DaVinci Resolve and should not be an issue , I belive.
I've seen the same thing, and this probably qualifies as a Photoshop bug. Auto Align works well, but the result is sometimes offset a few pixels. The final result is always perfect, it's just this curious offset.
Just press ctrl+1 to go to View > 100%, and nudge with the arrow keys, pixel by pixel. 100% maps one image pixel to exactly one physical screen pixel.
I'm not too bothered by it, actually you sometimes need to nudge a few pixels anyway, to compensate for irregular lens geometry. So I'd always double check at 100% in any case.
Thank you very much for clarifying this. One last question - when I focus stack, and there is some focus breathing, the geometry of the different layers will change slightly. Will auto align correct this, so that the nudge of the pixels will be the same over all parts of the image, or will I have to live with the fact the alignment will be perfect in the center, but not the edges ?
No, focus breathing is a real optical problem outside the scope of Photoshop. It's a variant of parallax error caused by the optical center of the lens moving "into" or "away from" the scene.
The best way to correct it is to prevent it, and you do that with a focusing rail. Moving the whole camera/lens assembly, without using the focusing ring on the lens, will improve things considerably because less movement is needed. The ultimate solution is a bellows system with a fixed lens, and just the camera body moving to focus.