Parallax Problem?

Glenn NK

I’m having some trouble with focus stacking - typically I start the "focus range" on the nearest part of the object, and successively focus farther away for each subsequent image.

However, what is seen in the viewfinder and captured with each successive image are wider and wider views - which essentially means I’m creating a parallax problem between successive images.

The result is usually a faint double image - a ghost along the edge of a leaf for example.

Someone suggested leaving the focus constant and moving the camera progressively closer to/farther from, the object, but that too essentially creates a parallax problem.

I'm usually shooting flowers, some of them with considerable "depth" from the nearest to the farthest focus point. A huge problem would be a dahlia that has spikes sticking out in all directions - parallax is a major problem with these.

The lens is a Canon 100 f/2.8 macro.

Skippy

Glenn NK wrote:

I’m having some trouble with focus stacking - typically I start the "focus range" on the nearest part of the object, and successively focus farther away for each subsequent image.

However, what is seen in the viewfinder and captured with each successive image are wider and wider views - which essentially means I’m creating a parallax problem between successive images.

The result is usually a faint double image - a ghost along the edge of a leaf for example.

Someone suggested leaving the focus constant and moving the camera progressively closer to/farther from, the object, but that too essentially creates a parallax problem.

I'm usually shooting flowers, some of them with considerable "depth" from the nearest to the farthest focus point. A huge problem would be a dahlia that has spikes sticking out in all directions - parallax is a major problem with these.

The lens is a Canon 100 f/2.8 macro.

Hi there Glenn, our resident MACRO King, Lord V. does most of his stacked shots by hand, and to tell you the truth I am still stumped as to how he does, but yes he hand holds his shots for his stacked images.

I'm sure he will offer you up some advice when he sees this thread.

Have you read his HOW TO Thread about stacking images ???
Here's the link ... http://www.dgrin.com/showthread.php?t=50752

... Skippy
.

Lord Vetinari

Hi Glen,

No matter how you take the pictures (move the camera or use the focus ring) the FOV will change. The software automatically resizes the images to account for this but the big problem is very OOF areas are always larger than in focus areas so you tend to get haloing around sharp edges. The easiest thing to do is to just clone the offending halos off or as I sometimes do, repair clone from the original pics back onto the stacked pic.
Haloing is always worse if there are rotational differences between the pics.

Brian V.

Glenn NK

Lord Vetinari wrote:

Hi Glen,

No matter how you take the pictures (move the camera or use the focus ring) the FOV will change. The software automatically resizes the images to account for this but the big problem is very OOF areas are always larger than in focus areas so you tend to get haloing around sharp edges. The easiest thing to do is to just clone the offending halos off or as I sometimes do, repair clone from the original pics back onto the stacked pic.
Haloing is always worse if there are rotational differences between the pics.

Brian V.

Brian:

First, thanks for the reply.

I rather suspected that there wouldn't be an optical solution to the problem, and your comments confirm this so I won't have to waste time and effort trying to find "the perfect lens" that could eliminate the situation.

I have been doing both cloning and air-brushing (if the halo occurs where the BG is uniform without pattern).

It never occured to me to clone parts from the original image(s); this will require some further learning on my part in the use of PP. My software consists of DPP (which I seldom use now), Lightroom (for basic adjustments), CombineZM, and Photoshop Elements 6.0.

I suspect PSE will be the one to use, but don't have a clue how to clone from one image to another. Any hints on this? There is a "clone stamp" in PSE, but it uses only copies parts of one image to other parts of the same image. What you're suggesting would require a different tool it seems.

Lord Vetinari

Glenn NK wrote:

Brian:

First, thanks for the reply.

I rather suspected that there wouldn't be an optical solution to the problem, and your comments confirm this so I won't have to waste time and effort trying to find "the perfect lens" that could eliminate the situation.

I have been doing both cloning and air-brushing (if the halo occurs where the BG is uniform without pattern).

It never occured to me to clone parts from the original image(s); this will require some further learning on my part in the use of PP. My software consists of DPP (which I seldom use now), Lightroom (for basic adjustments), CombineZM, and Photoshop Elements 6.0.

I suspect PSE will be the one to use, but don't have a clue how to clone from one image to another. Any hints on this? There is a "clone stamp" in PSE, but it uses only copies parts of one image to other parts of the same image. What you're suggesting would require a different tool it seems.

I use the repair brush - I'd be suprised if PSE does not have this - you just alt left click on the donor image and then paint onto the stacked image. Think it's just not obvious that you can do this from one image to another. You'll soon get the idea how I do stacks by hand
Brian V.

Glenn NK

Lord Vetinari wrote:

I use the repair brush - I'd be suprised if PSE does not have this - you just alt left click on the donor image and then paint onto the stacked image. Think it's just not obvious that you can do this from one image to another. You'll soon get the idea how I do stacks by hand
Brian V.

For a moment I was puzzled by what you said, but I think a light just went on - thanks. I forgot that one can load more than one image into PS at a time.