Stacking at 5:1, Not Entirely Happy with the Results: Yet another damp and cold Saturday in Wales so I though I would have a go at Stacking at 5:1 (not been above 3:1 before now).

PaulBa Loc: Cardiff, Wales

Yet another damp and cold Saturday in Wales so I though I would have a go at Stacking at 5:1 (not been above 3:1 before now). Maybe not the most exciting of subjects but at least they didn't crawl away.

I've shared the best two.

While initially fairly happy with the results closer inspection revealed a few areas of concern

1. when zoomed in the subject are not a sharp as I would have hoped
2. a few of the subjects appeared to have a halo around them as you can see down the right hand side of the twig.

The dust trails (removed) show evidence of movement about halfway through the twig stack but apart from that they appeared fairly straight.

Any suggestions or explanations will be gratefully received.

Technical Data: Canon 6D, MP-E 65, F8, 180 sec, ISO 200, step size 0.037mm, lighting two strobes defused.

Peppercorn
Peppercorn...

(Download)

Twig
Twig...

(Download)

tinusbum Loc: east texas

those look great in download! i see what you mean in double download.you might try f5 or is it f5.1 anyway that might work better at 5x1

Mark Sturtevant Loc: Grand Blanc, MI

I too felt they were not as sharp as expected. Perhaps the wider aperture as tinusbum suggests will give greater sharpness.
Not sure how to prevent the halo effects in the first place. Is there a way to do that?

PaulBa Loc: Cardiff, Wales

tinusbum wrote:

those look great in download! i see what you mean in double download.you might try f5 or is it f5.1 anyway that might work better at 5x1

Thanks tinusbum, I’ll try F5 next time.

PaulBa Loc: Cardiff, Wales

Mark Sturtevant wrote:

I too felt they were not as sharp as expected. Perhaps the wider aperture as tinusbum suggests will give greater sharpness.
Not sure how to prevent the halo effects in the first place. Is there a way to do that?

Thanks Mark, it’s good to know I’m not the only one who thinks they could be a little sharper.

LoneRangeFinder Loc: Left field

What software did you use to do the stacking?

If you saved the “slices”, you might try a 30 day trial of Helicon Focus. It will stack raw—and it does a pretty good job on higher mag stacks. F5.6 is my “go to” aperture for stacking. With a wider open aperture you may also lose just enough coverage that you may have to change the incremental setting.

PaulBa Loc: Cardiff, Wales

LoneRangeFinder wrote:

What software did you use to do the stacking?

If you saved the “slices”, you might try a 30 day trial of Helicon Focus. It will stack raw—and it does a pretty good job on higher mag stacks. F5.6 is my “go to” aperture for stacking. With a wider open aperture you may also lose just enough coverage that you may have to change the incremental setting.

Thanks for taking the time to comment Alan.

I use ZereneStacker but not adverse to changing if need be.

I’ll try F5.6 next time which will reduce my step size to 0.026mm

LoneRangeFinder Loc: Left field

PaulBa wrote:

Thanks for taking the time to comment Alan.

I use ZereneStacker but not adverse to changing if need be.

I’ll try F5.6 next time which will reduce my step size to 0.026mm

Zerene is good. I have both Zerene and Helicon. A 30 day test drive can’t hurt...

EnglishBrenda Loc: Kent, England

fjwallace

I think it is diffraction limiting. When you shoot at high magnification the effective aperture changes a lot. Eff Ap. = lens aperture x (1+magnification) so f8x6 = f48. Are you using D-Map or P-Map. I get these effects sometimes when I choose the wrong number in D-Map - could also be edge effects - as you change focus the edges change and blur. Hope that help.

PaulBa Loc: Cardiff, Wales

EnglishBrenda wrote:

Thanks for the thumbs-up Brenda

PaulBa Loc: Cardiff, Wales

fjwallace wrote:

I think it is diffraction limiting. When you shoot at high magnification the effective aperture changes a lot. Eff Ap. = lens aperture x (1+magnification) so f8x6 = f48. Are you using D-Map or P-Map. I get these effects sometimes when I choose the wrong number in D-Map - could also be edge effects - as you change focus the edges change and blur. Hope that help.

Thanks for taking the time to comment fjwallace, I'm going to rerun the stack at F5, as advised, hopefully that will improve sharpness.

I'm not sure what "wrong number in D-Map" means, so I'll look into that.

cactuspic Loc: Dallas, TX

I would open up to either f/ 2.8 or 4.0 at 5x magnification. With my 65 MP-E, I think 4.0 is the sharpest aperture but you should check with yours. At 5x my stacking interval is .025mm (for f/2.8) .051mm (for f/4.0). Do you use Zerene or Helicon of some other stacking software? If you use Zerene there are ways to retouch so that your edges are very sharp with little fringing. You use Zerene, let me know and I will explain it.

PaulBa Loc: Cardiff, Wales

cactuspic wrote:

I would open up to either f/ 2.8 or 4.0 at 5x magnification. With my 65 MP-E, I think 4.0 is the sharpest aperture but you should check with yours. At 5x my stacking interval is .025mm (for f/2.8) .051mm (for f/4.0). Do you use Zerene or Helicon of some other stacking software? If you use Zerene there are ways to retouch so that your edges are very sharp with little fringing. You use Zerene, let me know and I will explain it.

Thanks for taking the time to comment cactuspic.

I will be reducing the aperture to at least F5 for my next session as advised by LoneRangeFinder tinusbum and now yourself.

I currently use Zerene but plan to take advantage of the Helicon Focus 30 day free trial to see how that performs.

Sadly my “photography time” is limited so I may not be able to try this out for a week or two which probably explains why my progress has been slow over the last couple of years. However, the friendly folk in this section of the forum are very patient.