I Need a Little Help

A forum to ask questions, post setups, and generally discuss anything having to do with photomacrography and photomicroscopy.

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photosbytw
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Joined: Fri Oct 26, 2018 7:43 pm
Location: Northeast Georgia

I Need a Little Help

Post by photosbytw »

When I program the Stackshot I get an additional image which has not been a problem......until now. When I ran a stack of 25(I programmed a run of 24) I got, for the lack of better terminology, stretch marks. When I removed the 1st image all was fine.......What am I doing wrong.Image
Hopefully I've posted in the proper forum...........
Since I have retired and I've rekindled a love for photography. I don't take myself serious but I do take creating interesting and well executed images seriously.

zed
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Post by zed »

Likely an alignment issue - or something was moving. Do you have 'Automatic Order' selected in your preferences? If not do so:

https://zerenesystems.com/cms/stacker/d ... hy_is_that

cube-tube
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Location: Durham, NC

Post by cube-tube »

It looks like an artifact of your stacking software's image alignment. My guess would be that your camera is not perfectly parallel to the direction of the rail, causing a slight sideways shift with each frame. When the frames do not align well, the software automatically extends the image downward to fill the frame.

You said that removing the first image fixes the problem--in that case, it might just be the first image that is misaligned.

I would try adjusting the alignment settings in your software, removing the images that are causing problems in the stack or, even easier, just cropping the output to remove the stretch marks.

rjlittlefield
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Post by rjlittlefield »

These are classic edge streaks, as explained at the link that zed gives. (Full disclosure: I'm the fellow behind Zerene Stacker.)

Because the streaks go away when you delete just the first image, clearly the problem is that the first image is not well aligned with all the others. That often happens when the StackShot rail reverses direction, due to various forms of mechanical backlash in the carriage movements.

The standard solution is to adjust your shooting protocol, so that the rail has always been moving in the same direction just before it stopped at any critical points. For example: if you have moved forward to set Start (one critical point), then be sure to move forward to set End (another critical point), then before starting to take pictures, manually back up to beyond the Start point, so that the rail will have to move forward again to reach Start and begin shooting.

This approach allows all the images to be well aligned with each other, which preserves the maximum number of good pixels in the frame.

--Rik

photosbytw
Posts: 24
Joined: Fri Oct 26, 2018 7:43 pm
Location: Northeast Georgia

Post by photosbytw »

A big thanks to all for responding..........

tw
Since I have retired and I've rekindled a love for photography. I don't take myself serious but I do take creating interesting and well executed images seriously.

Deanimator
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Joined: Tue Oct 23, 2012 7:01 pm
Location: North Olmsted, Ohio, U.S.A.

Post by Deanimator »

rjlittlefield wrote:The standard solution is to adjust your shooting protocol, so that the rail has always been moving in the same direction just before it stopped at any critical points. For example: if you have moved forward to set Start (one critical point), then be sure to move forward to set End (another critical point), then before starting to take pictures, manually back up to beyond the Start point, so that the rail will have to move forward again to reach Start and begin shooting.

This approach allows all the images to be well aligned with each other, which preserves the maximum number of good pixels in the frame.

--Rik
I had never seen this before, and it quite likely will solve some of my similar issues.

We'll see in a week or two... :D

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