Auto Align Layers creating alignment issue

[eddybaby]

I am shooting 3 mutiple exposures of the same fixed image. The 3 images have been taken on a Canon 5D Mk IV on a tripod with a remote shutter release at the same wide aperture with the same fast exposure. There is no reason for the frames to be misaligned.

I want to blend those layers, and want to ensure the 3 frames (3 layers) are all aligned. On the layers when I zoom in all 3 appear aligned. Yet when I appy >Auto-Align Layers>Auto there shows some pixels misaligned left and top.

Am I doing something wrong, and how can I be 100% certain layers are competely aligned?

[D Fosse]

It happens that auto align offsets by a couple of pixels. I just nudge with the arrow keys (at 100%!) and make no more of it. Just make it a habit to check before committing.

IME the final result is always spot on, it's just maybe that little two or three pixel offset.

[eddybaby]

But in this instance, Auto-Align is creating misalignment when there isn't any. Why?

[D Fosse]

Are you saying it introduces actual geometrical distortion in one frame? Not just a general offset of a couple of pixels?

Are you viewing at 100% - one image pixel to one screen pixel? That's really important.

[eddybaby]

Have a look at these along the left side at 100%: before auto alignment and after. I am almost certain there was no alignment issue before applying Auto-Alignment.

[JJMack]

Post the three images

[Chuck Uebele]

I don't use auto align for that, maybe the reposition setting, as auto align, might distort. Either that or as Dag suggested: nudge the images.

[happie_97]

I agree with all the suggestions as auto align does mildly distort the images. I would try Chuck’s method if you want to prevent distortion.