I need help with Focus Shift.

[monte12345]

I can sort of get it to work but cannot get the last frame in the stack to focus on the most distant object. I suspect the problem is how I'm using this mode.

So, Settings. Number of shots = 15

Focus Step Width = 1

Interval until next shot = 0"

First Frame Exposure lock = ON

Silent Photography = ON

Starting Folder = New Folder

Subject focus for nearest object is at the closest point in the bottom of the frame, typically about 3 feet for 24mm. Hit start and I get 7 images shifting from the closest point to some distance a bit short of infinity and then the camera cycles back to the starting point and runs another sequence that stops a bit short of infinity with the last pic a repeat of the starting point.

As I stated earlier I am doing something wrong. I suspect it's the Interval to next shot deal. Problem is determining what interval will put me at infinity has me a bit baffled. However I am shooting a landscape with a 24mm setting on my 24-120 so getting within say 3 feet short of infinity will be perfectly good. My real issue is what is the distance that is 3 feet short of infinity. Would doing the math to get it sharp at 60 feet work? That would work out to roughly 30 shots with the interval set to 24". Second question is how would the Focus Step Width be effected? Actually if the interval distance is set does that null out the Focus Step Width?

 

[jthomas39]

(you don't say which Z camera you have.)

I don't do focus shift shooting, but that "interval" is timing between shots, not distance.

The Z6 online manual and the Z6 iii online manual both have similar settings for focus shift. It looks like the Z6 iii has a little more explanation and tips.

Z6 iii focus shift page from the online manual.

 

[jthomas39]

A quick test, Z6 iii, 24-120 at f/4, 24mm.

closest focus at about 5 feet. step size of 1, 20 shots. This took 9 images, it stops at infinity.

50mm at f/1.8. step size 1, 120 shots. It took about 30 images.

The useful Hogan's Guide to the Z6 iii says that the interval focus change is based on the camera's calculation of the focus depth of the current lens setting.

Note: The greater the starting focus distance, the fewer shots
you’ll need. The shorter the starting focus distance, the
more shots you’ll need.

Likewise, the faster the aperture (e.g. f/2.8) the more shots
you’ll need. The slower the aperture (e.g. f/11) the fewer
shots you’ll need.

 

[monte12345]

Like your explanation but it is simply a clearer version of what I got out of the Z7 II Reference manual. I had really hoped someone would spot something I got wrong. Because the final image does NOT end at infinity focus, it's either slightly ahead or behind that point. BTW my understanding is that the AF-S and mirrorless Nikkors can actually go past the true Infinity focus point. So is there a setting somewhere in the Z7 II menu system that can effect what the camera determines is Infinity? Following are three images from a first attempts at pixel shift. Note they have been downsized and are for illustration only but they clearly illustrate what I am seeing with first shot sharp at the foreground point and following images focused I have no idea where.

638

639

640

 

[Hesman]

I have not had much luck using Focus Shift with landscape photography and my Z6II. In the research I have done, written how to’s and YouTube videos, I found out that only a few pictures need to be taken for landscape photography focus stacking. I remember one suggestion was no more than 5 pictures for number of shots. Also “focus shift width” needs to be bigger than 1 for landscape photography if the focus shift feature is used. Using 1 on “focus shift width” works the best for macro focus shift photography.

Whenever I do focus stacking for landscape photography, I don’t bother using the Focus Shift feature. I will take 3-6 photos and select a focus point that is focusing on something farther away from the camera each time I take a picture. This usually works best when there is something close to the camera in the foreground that you want to be in focus.

 

[just Tony]

Like your explanation but it is simply a clearer version of what I got out of the Z7 II Reference manual. I had really hoped someone would spot something I got wrong. Because the final image does NOT end at infinity focus, it's either slightly ahead or behind that point.

One way to fail to reach infinity is to set too low a number for the exposure count. In the manual page that was linked it says that if the number is higher than necessary to reach that far, it will stop there without executing the full sequence you allowed, because it’s not necessary. If you are right about the focus going beyond that sounds like a defect.

As to the dual sequences from one start command, I have no idea and haven’t experienced that.

BTW my understanding is that the AF-S and mirrorless Nikkors can actually go past the true Infinity focus point. So is there a setting somewhere in the Z7 II menu system that can effect what the camera determines is Infinity?

It’s likely that focus position is known internally by each lens. There is an encoder whose reading is cryptically presented in the exif data. The Z lenses “know where they are” in the focus range, at least approximately.

Following are three images from a first attempts at pixel shift. Note they have been downsized and are for illustration only but they clearly illustrate what I am seeing with first shot sharp at the foreground point and following images focused I have no idea where.

638

639

640

--
Wag more; bark less.

 

[Ruby Rod]

I use focus shift all the time for macro and product photography. You definitely want enough shots so the lens can focus out as far as needed. I also don't set the step size at the minimum, maybe just under half. That said, I can't see why it's necessary for most landscape photography. Just stop the lens down. Or, if you've got a simple scene, take two or three shots focused manually on the planes of interest and stack those.