Help with focus stacking

[PeterAit]

I am just not getting the sharpness I think I should. As far as I can tell I am doing everything right. Any ideas?

1) Nikon D-600 with Nikkor 105mm macro lens shooting at f5.6.
2) Tripod mounted with focus rail, manual focus.
3) Remote shutter release.
4) Move camera a few mm after each exposure (the subject is about 1" deep).
5) Open images as layers in PS CC.
6) Edit->Auto Align Layers.
7) Edit->Auto Blend Layers.
Flatten

[PeterAit]

I am just not getting the sharpness I think I should. As far as I can tell I am doing everything right. Any ideas?

1) Nikon D-600 with Nikkor 105mm macro lens shooting at f5.6.
2) Tripod mounted with focus rail, manual focus.
3) Remote shutter release.
4) Move camera a few mm after each exposure (the subject is about 1" deep).
5) Open images as layers in PS CC.
6) Edit->Auto Align Layers.
7) Edit->Auto Blend Layers.
Flatten

Seems I have answered my own question - it was simply that I was not taking enough slices.

[Bart_van_der_Wolf]

Seems I have answered my own question - it was simply that I was not taking enough slices.

Hi Peter,

I was just about to ask, what is the image magnification factor?

If you are at 1:1, with a 105mm lens at f/5.6, the DoF is 0.136 millimetres (approx. 0.0054 inches), and that should then be the step increment for perfect, seamlessly connecting slices. That would take some 185 slices to cover 1 inch of distance. That is assuming that you'd want full size output files, so for half the pixel dimensions you'd half the number of slices by doubling the interval distance. Reducing the magnification factor also rapidly reduces the number of required slices, because you gain DoF per image.

Added to that, Photoshop's resampling quality (focusstacking requires to change the magnification of all images but one in order to register the images) is not as good as can be gotten from dedicated stitching programs, and it would probably choke on the number of images anyway.

Cheers,
Bart

[PeterAit]

Bart,

Thank you for all the information. I had no idea that DOF was so shallow. I was at about 0.5x.

Is there a dedicated stitching program that you would recommend?

[Bart_van_der_Wolf]

Bart,

Thank you for all the information. I had no idea that DOF was so shallow.

Yes, but only if you want pixel perfect output at something like 20 x 14 inches that survives close inspection. Smaller sizes are more forgiving, everything scales proportionally.

I was at about 0.5x.

DoF becomes 0.42 mm (approx. 0.0164 inches) at  1:2, almost 60 shots to cover 1 inch depth (maximum quality).

Is there a dedicated stitching program that you would recommend?

If you have to do this a lot, a program like Helicon Focus, or a similar one like Zerene Stacker, will save the day.

Helicon Focus comes with a utility (Helicon Remote) that allows to automate the stacking sequence with AF lenses (by bracketing the focus between closest and furthest distance), or an automatic focusrail like the Stackshot (also supported by Zerene stacker, if I'm not mistaken). If deep stacks (like dozens of shots) are required, an automation of the capture process is almost mandatory if you don't want to lose your sanity.

Cheers,
Bart

[Mark Lindquist]

Yes, but only if you want pixel perfect output at something like 20 x 14 inches that survives close inspection. Smaller sizes are more forgiving, everything scales proportionally.

If you have to do this a lot, a program like Helicon Focus, or a similar one like Zerene Stacker, will save the day.

Helicon Focus comes with a utility (Helicon Remote) that allows to automate the stacking sequence with AF lenses (by bracketing the focus between closest and furthest distance), or an automatic focusrail like the Stackshot (also supported by Zerene stacker, if I'm not mistaken). If deep stacks (like dozens of shots) are required, an automation of the capture process is almost mandatory if you don't want to lose your sanity.

Cheers,
Bart

Hi Bart,

Of the two, Zerene and Helicon, do you prefer one over the other?

Thanks-

Mark

[Bart_van_der_Wolf]

Of the two, Zerene and Helicon, do you prefer one over the other?

Hi Mark,

I've been using HeliconFocus for a long time, even long before Zerene Stacker became available. So my experience is with HF not ZS, although from what I read it's also very good. I don't think that there is much difference in the results they can produce, both are competent stackers.

HF has a good name in scientific circles (e.g microscopy, and all sorts of macro subjects), probably because it is already around for along time, and ZS is popular amongst many Photomacrography enthusiasts, probably because the programmer Rik Littlefield is also a moderator at a large forum (http://www.photomacrography.net/) for that specialized field.

HF also has an application (Helicon Remote, also for tablets and phones) to control your AF lens or an automatic focus rail, and integrates with the actual stacking program. AFAIK Zerene Stacker does not offer its own application to manage the capture process.

Cheers,
Bart

[Mark Lindquist]

Thanks Bart.  I've played with Zerene stacker some and not Helicon.  Zerene seemed to be brain dead simple though.  They advocate lens focal adjustments rather than rail adjustments for anything bigger than golf balls.  Cam Ranger has a good capture program - I use that.

Appreciate your feedback -

Mark

[Bart_van_der_Wolf]

Thanks Bart.  I've played with Zerene stacker some and not Helicon.  Zerene seemed to be brain dead simple though.  They advocate lens focal adjustments rather than rail adjustments for anything bigger than golf balls.

The Zerene website has a nice overview of the benefits of each approach, (focus)ring versus rail.

Cam Ranger has a good capture program - I use that.

Yes, that's what they suggest at Zerene as well, if you already have the CamRanger.

Appreciate your feedback -

You're welcome.

It's a bit too expensive to add to my already present Helicon Focus based solution, which works great. Maybe I'll install the trial version of Zerene, but I have not all that much time to do a thorough comparison, and especially when the results are expected to be quite similar (same basic algorithms). It would be nice to compare the Retouching capabilities of both, I know Helicon's to be quite good, and Retouching is going to be required at times (especially on occlusions and wide apertures).

Cheers,
Bart