Advice sought on weird stacking artifact from mirrorless rental

[MarkSturtevant]

I am renting the Canon R7 mirrorless camera, with an idea to maybe buy it straight from the rental company (they have good deals about that). One feature that really attracts me is that it does focus bracketing -- and boy does it do it fast! Only problem is, when I go to stack the pictures in Zerene it always gives me this weird artifact where about every other picture is visibly skewed from adjacent pictures. Obviously this renders an unusable stack.
I had thought that the problem was bc I had the Image Stabilizer running in the lens. It made sense that while doing a hand-held (but well braced) stack, the lens assembly would be jiggering around a little, producing this effect. But turning the lens IS off did nothing to cure the problem. The lens is my trusty Canon 100mm f/2.8 L, attached to the camera with an adapter.

There is still IS running in the camera body, and maybe that is doing it? I don't think the sensor tilts around in Canon bodies, does it? The descriptions I've read seem like it's different. I have not tried to turn that off yet. And I've not heard of this problem before.
I doubt its me. I do focus bracketing by hand all the time with the same lens (on a different body). I've never seen this.
I am trying to show the effect here as a gif animation, taken as screen grabs from Zerene after alignment.
What could be causing this? The camera is due back on Monday. I may send it back.

[RobertOToole]

I am renting the Canon R7 mirrorless camera, with an idea to maybe buy it straight from the rental company (they have good deals about that). One feature that really attracts me is that it does focus bracketing -- and boy does it do it fast! Only problem is, when I go to stack the pictures in Zerene it always gives me this weird artifact where about every other picture is visibly skewed from adjacent pictures. Obviously this renders an unusable stack.
I had thought that the problem was bc I had the Image Stabilizer running in the lens. It made sense that while doing a hand-held (but well braced) stack, the lens assembly would be jiggering around a little, producing this effect. But turning the lens IS off did nothing to cure the problem. The lens is my trusty Canon 100mm f/2.8 L, attached to the camera with an adapter.

There is still IS running in the camera body, and maybe that is doing it? I don't think the sensor tilts around in Canon bodies, does it? The descriptions I've read seem like it's different. I have not tried to turn that off yet. And I've not heard of this problem before.
I doubt its me. I do focus bracketing by hand all the time with the same lens (on a different body). I've never seen this.
I am trying to show the effect here as a gif animation, taken as screen grabs from Zerene after alignment.
What could be causing this? The camera is due back on Monday. I may send it back.
Crab in R7.gif

Hi Mark,

I'm no Canon IS expert but pretty sure the lens has Hybrid IS, yaw and pitch (side to side), and angular correction (entire frame shifting side-to-side), but the R7 has yaw and pitch only as far as I know. Sorry I couldn't help more.

Extra points for the Crab spider!

[rjlittlefield]

I had another user report a problem like this, about two weeks ago, using Olympus E-M10 Mark III with Olympus 60 mm f/2.8 macro lens.

It was pretty mysterious on first encounter.

But after some thrashing around, we figured out that for him it's a rolling shutter effect. In focus bracketing mode, his camera always uses the full electronic shutter, which takes a long time to sweep across the frame. That long sweep time, combined with variable image movement across the sensor while the sweep is going on, causes some captured frames to be stretched and/or skewed compared with other frames. Probably some of the images are also nonlinearly warped within a single frame, but we did not test enough to confirm that.

I would bet heavily that your problem is the same. I have an R7, and I've determined experimentally that the full electronic shutter travel time is about 30 milliseconds (ref viewtopic.php?f=8&t=45281). Anything that causes the optical image to move laterally across the sensor during that time will cause the image to be skewed; anything that causes it to move vertically across the sensor will cause it to be stretched or squashed, depending on the direction of movement. Any of these can wreak havoc with Zerene Stacker's alignment process, which assumes that images vary only in overall scale, X/Y offset, and rotation.

Once the images have been captured like this, there is no great way to recover. Helicon Focus has the same trouble as Zerene Stacker. If the problem is only linear skew and/or stretching, then Photoshop or other pano stitching tools can maybe coerce the images into acceptable alignment. But if there's a nonlinear warp, caused by the movement changing during one frame's exposure time, then that's a much harder problem and I doubt that you'll get a perfect result from any tool.

This problem is new to me also. Your report and the other fellow's are the only examples that I've seen, and I have not yet tried to reproduce it with my own R7. Whatever further information you or anyone else can provide will be most appreciated.

--Rik

[MarkSturtevant]

Thank you, Rik. The R7 goes to electronic shutter when doing focus bracketing, and there it takes pictures at 30 frames per/sec. I don't see a way to get it to not use that shutter mode during focus bracketing.

[Troels]

I do a lot of handheld focus bracketing and have experienced the same problem several times with both Olympus OM-D E-M5 og E-M1 II.
I also suspected it was caused by the IBIS stabilazation moving the sensor around during exposure.
Anyway, speeding up the shutter seems to reduce the problem. Since the bracketing is so fast it is no problem to increase the number of exposures caused by a bigger aperture of say 2.8 or 3.6.
With shutter speds of 1/1000 sec. or faster the problem seems to disappear.

[Marcepstein]

Hey Mark,
I have the R7 and focus bracket lots with small issues here and there mostly because of the settings I used in-camera confounding the process. I have used full electronic and 1st curtain electronic shutter with no issues. If you are using a manual lens, auto focus bracketing wont work and you have to increment individual shots like I do when I use the MPe65.

With a auto focus lens - I have set the camera for a 10 sec shutter delay so the vibration is nil. It works fine. But turn off ALL unnecessary functions in the menus, like al savo, focus tracking, eye track, anything like that and use one shot not al servo. I set the camera to M mode both on the top dial and on the front of the camera but keep the lens in auto focus. Turn off IS on lens and body. I am using a focus rail and tripod for stability. Make sure its not in movie mode. I just use 1st curtain electronic shutter and 100 iso. I also set the bracket index to the lowest point (1) in the menu.

I have found that the R7 shutter will not engage unless the subject is in focus. There are several work arounds but to start I find the outer most spot on the subject, 1/2 press the shutter release to keep it in focus while slowly turning the rail to move the focus point slightly out of focus and then fully press the shutter release (you can control shutter release with the camera app on an Iphone or pad if you can get it to work). The 10 sec delay resolves any vibration issue and the in-camera focus bracketing works fine. I have to watch the progress of the stacking on the back screen to the point that the process has fully bracketed across the subject and when all is out of focus, I press the shutter release to stop the process. Try this with a tripod and stationary subject to see if you get the same results.

Troels - I have not hand held and tried to stack but with the above process, and magnification 2-3x, Ive used shutter speeds as low as 1.5 sec with no issues. Maybe hand holding induces some movement and faster shutter resolves it.

[rjlittlefield]

For my other user, faster shutter time did not solve the problem. The reason is that the total sweep time remains unchanged at about 1/30 second. Setting a shorter exposure time causes each pixel to be exposed for less time so there may be less blur, but with the same total sweep time, movement still gives the same problems with overall geometry.

IF you can set the R7 to use only 1st curtain electronic shutter, then that would help because the sweep time is about 8 times faster.

But on my R7, enabling focus bracketing automatically sets full electronic shutter and I cannot find any way to override that. If somebody knows a trick to get around that, I would like to learn it also.

--Rik

[Marcepstein]

But on my R7, enabling focus bracketing automatically sets full electronic shutter and I cannot find any way to override that. If somebody knows a trick to get around that, I would like to learn it also.

No, there is something you have set in the menu options that is keeping it in full electronic shutter. Look at your menu options, here are my settings (I am not having that problem)

1st menu: #7, disable silent shutter function, enable shutter mode Elec. 1st curtain.
#9 display simulation, use exposure+dof, will allow you to see the picture with dof
AF menu: #1 AF operation ONE Shot, AF area (I use spot), subject track (off), subject detect (none), eye detect (disable), swithching tracked objects 0
#2 I have set to AUTO
#3 One shot AF release prior, Preview AF (Disable), Lens drive when AF imposible (off), I keep the auto assist beam on so I can see when the the operations starts, but wont affect if off
#4 Touch and drag AF settings (on), Limit AF areas (I use spot), Sensitivity AF point (0)< Orientation linked AF point (same for both vert/horz)
#5 MF peaking (on), focus guide (on), movie Servo (disable)
#6 Electronic full time MF (off), lens elect MF (one shot enabled)

Let me know if this helped because it works fine on my R7
Marc

[MarkSturtevant]

Thank you everyone, for all these responses.
My focus bracketing is hand held -- I am hard wired to doing things that way. I will explore the camera IS as being the cause.

A worry that I have now (it kept me up at night, thinking about it) is that it could be the lens after all. That is my olde and very well worn Canon 100mm f/2.8L. Although the lens IS is turned off, its possible that the glass in there could be out of alignment owing to a recent drop of my camera onto a forest floor. Not with the R7 body, mind you. That rental stays at home! The lens still works and I've used it for all sorts of things w/o problem because the way I normally do focus bracketing is all manual. I generally move the camera and not the focus ring, but if I ever used the focus ring for bracketing I might not notice any weird effects since not all attempts to free-lance focus bracket are successful anyway.
To best use the tremendous talents of the R7 and to significantly expand my capabilities, I want to use the automatic focus of the old lens during focus bracketing. The R7 is amazing in many other ways, but that feature is THE feature I'm after.
I am testing for this and for other possible causes as time allows today (got job related work to do). But if it turns out to be a glass alignment problem, then that might also be the unwanted answer to the problem with the Olympus camera that was mentioned.
Oy! But there is that Canon macro lens for mirrorless bodies ...

[WojTek]

Hello Mark,

Unfortunately, I don't have an R7, but an M6M2. But it is very similar.

I have been shooting exclusively with the full electronic shutter for years
and use the internal focus bracketing.
I use the EF 100L macro for this. So it is rather not due to the lens.

But I have not been able to achieve such an effect over the years.
The R7 must have something that the M6M2 does not.

Best, ADi

[JKT]

My first suspect here would be the long curtain time combined with hand-help photograpy. There's bound to be all kinds of movements within that 1/30 s and those are completely random between pictures in the stack.

[JKT]

Another thing caught my attention: In the first post you wrote that you turn the lens IS off, but the body IS is still running. In reality it is not. If you have an IS lens both IS systems are controlled by the lens IS switch. There is no way to get only one of them to work.

[rjlittlefield]

No, there is something you have set in the menu options that is keeping it in full electronic shutter. Look at your menu options, here are my settings (I am not having that problem)

Summary: I'm still getting full electronic shutter when focus bracketing.

In detail...

I reset everything to factory settings, then stepped through everything you mentioned:

1st menu: #7, disable silent shutter function✔, enable shutter mode Elec. 1st curtain✔.
#9 display simulation, use exposure+dof, will allow you to see the picture with dof✔
AF menu: #1 AF operation ONE Shot✔, AF area (I use spot)✔, subject track (off)✔, subject detect (none)✔, eye detect (disable)✔, switching tracked objects 0✔
#2 I have set to AUTO✔
#3 One shot AF release prior✔ ("release"), Preview AF (Disable)✔, Lens drive when AF impossible (off)✔, I keep the auto assist beam on so I can see when the the operations starts, but wont affect if off ✔(AF assist on)
#4 Touch and drag AF settings (on)✔(enabled), Limit AF areas (I use spot)✔, Sensitivity AF point (0)✔, Orientation linked AF point (same for both vert/horz)✔
#5 MF peaking (on), focus guide (on)✔, movie Servo (disable)✔
#6 Electronic full time MF (off)✔, lens elect MF (one shot enabled)✔

Then I set focus bracketing to enabled and shot a focus stack. It went blindingly fast, about 100 frames in 5 seconds, making shutter noises from the speaker but with no mechanical shutter noise, and the captured images of a moving pencil clearly showed rolling shutter effects, skewed left or right depending on direction of movement. The menu system still shows shutter mode as "Elec. 1st-curtain" when focus bracketing is disabled, but as "Electronic" when focus bracketing is selected. In addition, the shutter mode line is grayed out, and if I press the Set button, I get a diagnostic "Not available because of the associated function's setting. Focus bracketing".

Does your camera behave differently?

My firmware is Ver.1.0.1 (Tools page 6). What is yours?

--Rik

[Marcepstein]

Summary: I'm still getting full electronic shutter when focus bracketing.

Rik,
My firmware is 1.3.1, My R7 is focusing bracketing without any issues? Although, I have had the same issue you are having and it was a setting in the menu that was causing it, if I remember correctly.

Ok, I go through some of the settings I didnt include thinking they might not have affected shutter function.

1st Menu:
#1 Image quality = Raw, Duel Pix Raw (disabled), aspect ratio 3:2
#2 ISO = 100, HDR-off, HRD mode-off, auto lighting optimiser-off, Highlight tone priority-off, anti flicker shoot-off
#3 Speedlight control- flash firing-enabled, ETTL balance-standard, ETTL II meter-eval (facePrty), Contin flash ctrl-ETTL each shot, slow synchro= 1/320-1/66 (Elec. 1st curtain)
#4 White balance AWB, WB Shift/Bkt=0, color space Adobe RGB, Pic Style=Standard, Clarity=0, creative filters-off
#5 Lens aberration correction- all off, long exp noise reduction-off, High ISO speed=standard, Dust delete-off
#6 all off except when I start focus bracketing, then I enable it.
#7 drive mode-10sec delay, Interval timer-disable, bulb timer-greyed out, silent shutter function=off, Shutter mode, Elec. 1st-curtain, Release shutter w/o card-off
#8 IS mode-off, auto level-disabled, Cust quick controls (this is for setting up C1-C3 custom functions, good idea to clear them if enabled), touch shutter-disabled, Image review-2sec, high speed display-greyed out, Meter time 8 sec
#9 Display sim- as before, shooting info disp-VF vert (on), grid display (off), histogram disp=brightness, lens display-focal length disp (enabled) the rest are greyed out,, Reverse display-off, VF display format=display 1, Disp. performance-power saving FPS and smooth,
#10 really for movies - default settings

AF Menu
#1 as before
#2 as before
#3 as before
#4 as before
#5 as before
#6 as before, focus ring rotation = normal, RF lens MF=varies with rotation speed (these shouldnt affect shutter function)

> Menu - default

WiFi - airplane mode off the rest is default

Wrench Menu
#1 Record func default except camera/movie separate=disabled, file numbering=continuous, auto rotate On, add movie rotate Disabled
#2 default except mode guide enabled
#3 default except power saving = all disabled
#4 Screen/viewfind = Auto 2, all default except UI magn = disabled
#5 Touch control = sensitive, Multi function lock (custom settings), switch am/mf greyed out, rest are default
#6 default settings

These are my current settings and the focus bracketing is working fine in 1st curtain. There is a function in Menu Wrench #3 (Beep and volume) where you can set the volume of shutter and focus beep. Maybe elevate the volume a little and see if you can hear the curtain when it closes. I read somewhere that the sound is the 2nd curtain closing but I cant find the source at the moment.

The focus bracketing is operating great on my R7. I am using the EOS ef 100mm 2.8f macro and shooting in M mode as noted above in response to Mark. I set the camera to M mode both on the top dial and on the front of the camera but keep the lens in auto focus. All IS is off.

Im curious if this help resolved the issue. Hope it helped.
Marc

An after the fact edit:
You could try to hook up a flash and see if it fires? I understood that the flash didnt work with full electronic shutter but it does work in Elec. 1st-curtain.. A double check on Elec. 1st-curtain vs full electronic shutter?

[rjlittlefield]

You could try to hook up a flash and see if it fires? I understood that the flash didnt work with full electronic shutter but it does work in Elec. 1st-curtain.. A double check on Elec. 1st-curtain vs full electronic shutter? [/b][/b]

OK, tried that. Using Canon 580EX II mounted direct on the camera, there's no flash when focus bracketing, but flash when single shot. Also a big difference in shutter sound for those two cases.

Ok, I go through some of the settings I didnt include thinking they might not have affected shutter function.

Stepping through what I did...
1st Menu:
#1 Image quality = Raw, Duel Pix Raw (disabled), aspect ratio 3:2. ✔all confirmed, no effect
#2 ISO = 100✔changed, HDR-off, HRD mode-off, auto lighting optimiser-off, Highlight tone priority-off, anti flicker shoot-off ✔all others confirmed, no effect
#3 Speedlight control- flash firing-enabled, ETTL balance-standard, ETTL II meter-eval (facePrty), Contin flash ctrl-ETTL each shot, slow synchro= 1/320-1/66 (Elec. 1st curtain) ✔ all confirmed, no effect
#4 White balance AWB, WB Shift/Bkt=0, color space Adobe RGB✔changed, Pic Style=Standard✔changed, Clarity=0, creative filters-off ✔all others confirmed, no effect
#5 Lens aberration correction- all off✔changed, long exp noise reduction-off, High ISO speed=standard, Dust delete-off✔none showing; ✔all others confirmed, no effect
#6 all off except when I start focus bracketing, then I enable it. ✔same
#7 drive mode-10sec delay✔changed, Interval timer-disable, bulb timer-greyed out, silent shutter function=off, Shutter mode, Elec. 1st-curtain, Release shutter w/o card-off✔, all others confirmed, no effect
#8 IS mode-off✔changed, auto level-disabled, Cust quick controls (this is for setting up C1-C3 custom functions, good idea to clear them if enabled), touch shutter-disabled, Image review-2sec, high speed display-greyed out, Meter time 8 sec, ✔all others confirmed, no effect
#9 Display sim- as before, shooting info disp-VF vert (on), grid display (off), histogram disp=brightness, lens display-focal length disp (enabled) the rest are greyed out,, Reverse display-off✔changed, VF display format=display 1, Disp. performance-power saving FPS and smooth, ✔all others confirmed, no effect
#10 really for movies - default settings✔defaulted

AF Menu
#1 as before
#2 as before
#3 as before
#4 as before
#5 as before
#6 as before, focus ring rotation = normal, RF lens MF=varies with rotation speed (these shouldnt affect shutter function),✔all confirmed

> Menu - default

WiFi - airplane mode off the rest is default✔confirmed (my airplane mode was defaulted to off)

Wrench Menu
#1 Record func default except camera/movie separate=disabled, file numbering=continuous, auto rotate On, add movie rotate Disabled✔these were default
#2 default except mode guide enabled✔that was default
#3 default except power saving = all disabled✔changed, no effect
#4 Screen/viewfind = Auto 2✔changed, all default except UI magn = disabled✔that was default, no effect
#5 Touch control = sensitive✔, Multi function lock (custom settings)?not sure, switch am/mf greyed out, rest are default✔no effect
#6 default settings

With all the above checked, I'm still getting full electronic shutter when focus bracketing, but 1st curtain electronic shutter for single shots.

So, either the issue is some other setting, or firmware version, or confusion, or something else that has not yet occurred to me.

These are my current settings and the focus bracketing is working fine in 1st curtain. There is a function in Menu Wrench #3 (Beep and volume) where you can set the volume of shutter and focus beep. Maybe elevate the volume a little and see if you can hear the curtain when it closes. I read somewhere that the sound is the 2nd curtain closing but I cant find the source at the moment.

Some of this description makes me worry about confusion, so before I start updating firmware I'm going to press for clarification.

For me, taking single pictures, there is a distinct difference in sound between full electronic shutter and 1st curtain electronic shutter. In full electronic shutter mode, there are soft clicks apparently from the speaker at start and end of exposure. Adjusting Menu Wrench #3 volume to 0 causes those clicks to disappear. In 1st curtain electronic shutter mode, there is a fairly loud mechanical clack-and-whir at the end of exposure, and those sounds are not affected by the Wrench #3 volume setting. The two modes are unmistakably different.

Now comes an awkward question...

What exactly do you observe that makes you think your focus bracketing is actually being done in 1st curtain electronic shutter mode, as opposed to automatically switching to full electronic mode as soon as you enable focus bracketing?

--Rik