Canon mirrorless R7: focus bracketing unreliable as to how many shots it executes

[Chiara66Cologne]

Hello there, 

I am Ulrike from Cologne, Germany. I got my R7 last year and I love working with it!

Yesterday I had a spontaneous little macro shooting. Camera on the tripod, everything correctly adjusted, wanted to have 15, at times 20 shots for the focus bracketing. Well, sometimes the 15 or respectively the 20 shots were done, but at times only a few (3-5) shots. The same motive, the same light... I have worked with the focus bracketing quite often, so now I wonder what is behind this behaviour.

Does any of you have an idea, what is going on?

Have a great sunday! 

[p4pictures]

I have experienced some focus bracketing sequences where the selected number of photos were not taken. For me this happens when the lens reaches the infinity focus position or with the selected aperture, infinity is well in focus. It also can depend on lens used as not all older lenses have small increments of focus like the modern RF lenses. 

One trick I have found to help with macro work using focus stacking is to use back button AF. By removing AF activation from the shutter you can AF with the back button, or simply pre-focus on the closest part of the subject using manual focus. I have sometimes even focused a little in front of the subject. Then when you press the shutter for the camera to start the focus bracketing sequence it starts from the initial focus you chose, and drives the lens correctly. 

[Chiara66Cologne]

Hello p4pictures,

thanks a lot for your answer. The thought did cross my mind that the end of the infinity focus position might play a role in this. I always use the same lens for macro photography, and yes, it is an old lens (sigma 105 macro, I love it!). Do you think that alone could account for the "unreliability"?

As I wrote, the motive and everything else was the same throughout the shooting and the R7 did perform the full amount of shots even AFTER having executed only 3 or 4, with the same position of the AF. I normally start at the very front with the AF; I think, it doesn't work otherwise, when you allow the camera to do the merge automatically. I always want to have the option to do the merging by hand, but often the automatic results are really good and I don't have to go through the tedious process by myself. 😉

I am simply wondering whether or not I should go to the shop from where I got my E7 with this "riddle". What would you do?

[p4pictures · Accepted solution]

It could also be a compatibility question for the lens and camera. Since you mentioned you have the Sigma 105mm then it's an EF mount lens. All the cameras with focus bracketing have some lenses that are better for use with focus stacking. Even Canon older EF macro lenses are not on this list

https://cam.start.canon/en/H001/supplement_0010.html 

If you go to the shop to try it would be good to try with a Canon lens on the supported list.

[Chiara66Cologne]

Thanks, will do!😊🙏🏼