question about stacking

paddler4

I usually stack with Zerene, using PMax. Generally, I have had halos and other edge junk with handheld shots if I don't maintain good enough alignment.

However, last night I found halos in images that I had taken on a tripod, with mirror lockup and a remote release. The images below are stacks of 17 shots, stacked with PMax and DMap. (I find that DMap sometimes does better with textures and retaining saturation when doing flowers). I did nothing before stacking other than WB adjustment. I exported 8 bit TIFFs from LR to load into Zerene.

The first two below are roughly 100%, as Zerene produced them. You can see that there is a halo in both cases, although they are different: PMax is dimmer and less even, clearly showing an echo of the edge of the anthers. The final shot is an edit, showing how clarity, contrast, and sharpening bring out the halo.

Is there a way to avoid this? I think an edge retouching would not work, because the image that has the anther in focus is far in front of the one that has the red background in focus, so the retouching would create blur in the red near the border--re-creating a halo.

Thanks for any suggestions.

PMax, unedited:



DMap, unedited:




DMap, edited:

Lord Vetinari

Halos like this with stacking software are almost inevitable when stacking a subject with a high contrast edge when there is detail showing in the background. You may be able to reduce them depending on whether you use PMax or DMap but I have never really tried DMap. I think the problem in this case is caused by the sofware actually trying to fill in an area that cannot actually be seen in the photographs because when the background is in focus the anther would have been a much larger blur and it would have masked a "halo" of background detail. I suspect if the stack had not been so deep that the background was not in focus you might have then got a white halo.
You can get rid of most of this type of halo in PS using the cloning brush at about 50%to take the detail closer in to the anther and then use the healing brush to remove any non blended lines that show further away from the anther.
Brian V.

paddler4

Brian,

thanks very much. Very helpful.

Dan