Feedback and advice on Coral Image
Moderators: rjlittlefield, ChrisR, Chris S., Pau
Feedback and advice on Coral Image
My first time posting so would appreciate any assistance.
I have undertaken a project to photograph live coral in a saltwater tank. Macro will vary from 1:1 to hopefully 5:1 if we can get it to work. It is surprising how much movement we get in these hard corals and they certainly react to the light ( Flash ) This is one of our first attempts with no processing apart from a quick levels. 160 stacked images ( Zerene) Canon 6D Mk11 with 100 macro.
Would love to know any thoughts on what we should be looking for regarding stacking issues /noise /sharpness etc. And suggestions on how to handle aligning of images that have subject movement would be appreciated.
I have a heap more questions but look forward to a start . Thanks..
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Re: Feedback and advice on Coral Image
capoty, welcome aboard!
Nice image -- I see that the bar for first-time posts has been raised once again.
If you're using flash as a way of freezing out vibration caused by camera shutter, then be sure to read up on how to use the camera's capability to use electronic first shutter curtain (EFSC). With EFSC, you should have no trouble getting sharp images with continuous illumination, assuming that the subject is not moving.
Best guess is that those are due to pushing the DMap contrast threshold slider too far left, so that the software makes mistakes by trying to infer depth from image content, even in areas where there's not enough sharp detail to do that correctly. The slider should be pushed right until those problematic areas go "black in preview". This is discussed in more detail in the tutorial "How To Use DMap", linked from the main Tutorials index page at https://zerenesystems.com/cms/stacker/d ... rialsindex .
Every focus stacking package that I know assumes that images can be aligned by linear operations on the entire image: shift/scale/rotate. If part of the subject moves with respect to another part, then no attempt is made to introduce nonlinear "warping" transformations to keep the moving parts lined up from frame to frame. (Photoshop will automatically do a bit of nonlinear warping, but it's really restricted to modeling lens distortions, which is commonly needed in side-by-side stitching applications.)
In some cases you might be able to use Stack Selected in combination with retouching to clean up problems caused by subject motion.
I hope this helps!
--Rik
Nice image -- I see that the bar for first-time posts has been raised once again.
Do you need to use flash for your stacked images? Subject movement will usually degrade a stack even if flash has made the individual images sharp. You might be better off to use continuous illumination and just accept some blurring in case of subject movement.It is surprising how much movement we get in these hard corals and they certainly react to the light ( Flash )
If you're using flash as a way of freezing out vibration caused by camera shutter, then be sure to read up on how to use the camera's capability to use electronic first shutter curtain (EFSC). With EFSC, you should have no trouble getting sharp images with continuous illumination, assuming that the subject is not moving.
The stack looks clean to me except for these "closed contour lines" in out-of-focus background:Would love to know any thoughts on what we should be looking for regarding stacking issues /noise /sharpness etc.
Best guess is that those are due to pushing the DMap contrast threshold slider too far left, so that the software makes mistakes by trying to infer depth from image content, even in areas where there's not enough sharp detail to do that correctly. The slider should be pushed right until those problematic areas go "black in preview". This is discussed in more detail in the tutorial "How To Use DMap", linked from the main Tutorials index page at https://zerenesystems.com/cms/stacker/d ... rialsindex .
That's a hard problem and I don't know any good way to do it.suggestions on how to handle aligning of images that have subject movement would be appreciated.
Every focus stacking package that I know assumes that images can be aligned by linear operations on the entire image: shift/scale/rotate. If part of the subject moves with respect to another part, then no attempt is made to introduce nonlinear "warping" transformations to keep the moving parts lined up from frame to frame. (Photoshop will automatically do a bit of nonlinear warping, but it's really restricted to modeling lens distortions, which is commonly needed in side-by-side stitching applications.)
In some cases you might be able to use Stack Selected in combination with retouching to clean up problems caused by subject motion.
I hope this helps!
--Rik
Thanks for the feedback everyone
Mike .. We really assumed that the glass was going to be an issue. Suprisingly we have had no problems. The water actually seems to act as a diffuser.
I am considering replacing the front glass on our tank with a thinner better quality glass though.
Appreciate the comments Rik. Initially we started with continuous lights but yes we got movement issues.. I was just reading up on the weekend about using EFSC as its not something I have needed in my normal photography. Sounds like I should go further down that path.
Cheers.. John
Mike .. We really assumed that the glass was going to be an issue. Suprisingly we have had no problems. The water actually seems to act as a diffuser.
I am considering replacing the front glass on our tank with a thinner better quality glass though.
Appreciate the comments Rik. Initially we started with continuous lights but yes we got movement issues.. I was just reading up on the weekend about using EFSC as its not something I have needed in my normal photography. Sounds like I should go further down that path.
Cheers.. John
Very beautiful.
It also makes me curious about magnification/field of view?
It also makes me curious about magnification/field of view?
Troels Holm, biologist (retired), environmentalist, amateur photographer.
Visit my Flickr albums
Visit my Flickr albums
Thanks again all for your nice comments. I am very surprised . This was our second attempt at a coral. the first was thwarted by water temp and coral reaction to that issue. The coral very quickly clouded the water
Its a bit closer than 1:1 100 mm macro plus diopter. We did attempt some images with a reversed 50mm Nikon lens on a 200 mm lens but by the time we got to that stage the coral was closing up. And with the movement the stacking looked horrible.
Our inspiration comes from an Australian site who as a complete newbie to macro I think are just fantastic.
http://www.microworldsphotography.com/G ... of-corals/
I look forward to learning a lot more from the project and this site.
Thanks.. John
Its a bit closer than 1:1 100 mm macro plus diopter. We did attempt some images with a reversed 50mm Nikon lens on a 200 mm lens but by the time we got to that stage the coral was closing up. And with the movement the stacking looked horrible.
Our inspiration comes from an Australian site who as a complete newbie to macro I think are just fantastic.
http://www.microworldsphotography.com/G ... of-corals/
I look forward to learning a lot more from the project and this site.
Thanks.. John
Daniel Stoupin is a forum member with the nickname Starshadecapoty wrote:Our inspiration comes from an Australian site who as a complete newbie to macro I think are just fantastic.
http://www.microworldsphotography.com/G ... of-corals/
Pau