Focus bracketing on Canon R6 and RF 100/2.8 lens

[rhirekat]

I have been trying to do focus bracketing on Canon RF 100/2.8 lens with mixed results. This is the problem I have encountered: The lens works with autobracketing only when it is on autofocus. Unlike in EF lenses (I use 180/3.5), I can not use manual focus ring while half pressing the shutter release button to focus on the closest point with RF 100/2.8 lens. The autofocus often misses the closest point resulting in images that are blurry in areas that are closest to the camera. Are there any tricks to make the lens autofocus on the closest point or to use the focus ring while half-pressing the shutter release button? How do the pros do it? I think it is a drawback in an otherwise excellent lens. 

[Waddizzle]

“I have been trying to do focus bracketing on Canon RF 100/2.8 lens with mixed results. This is the problem I have encountered: The lens works with autobracketing only when it is on autofocus.”

I believe using autofocus is crucial to how automatic focus bracketing functions.  

Judging from what I have read about it, automatic focus bracketing seems to require a little experimentation for every macro shooting scenario.  The DoF can be surprisingly narrow.  It sounds like you are encountering issues invoking manual focus override.  What AF mode are you using?

The first images is an example of just how narrow DoF can be when capturing a series of images.  There is a VERY narrow [horizontal] band of sharp focus across the center of the coin.  I captured a series of images, manually refocusing the lens so that the narrow band of focus moved from the top of the image to the bottom. 

The second image is what the final result looked like after combining 60 images.  I used One Shot AF Mode and the lens AF/MF switch in the MF position.  Hope this helps.

[deebatman316]

All RF lenses wether STM or USM use Electronic focus rings. Make sure Manual Focus After One Shot is Enabled in the camera menu. If not manual focus override will NOT work. This setting is set to Disable by default. Also Manual Focus override does NOT with Servo AF and AI Focus it only works with One Shot.

-Demetrius

Current Gear: 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 50 F/1.8 STM, EF 85mm F/1.8 USM, EF 70-200mm F/2.8L IS III USM, 430EX III-RT, 470EX-AI & 600EX II-RT

Retired Gear: EOS 40D, Sigma 17-50mm F/2.8 EX DC OS HSM & EF 28-135mm F/3.5-5.6 IS USM

[FloridaDrafter]

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@rhirekat wrote:

I have been trying to do focus bracketing on Canon RF 100/2.8 lens with mixed results. This is the problem I have encountered: The lens works with autobracketing only when it is on autofocus. Unlike in EF lenses (I use 180/3.5), I can not use manual focus ring while half pressing the shutter release button to focus on the closest point with RF 100/2.8 lens. The autofocus often misses the closest point resulting in images that are blurry in areas that are closest to the camera. Are there any tricks to make the lens autofocus on the closest point or to use the focus ring while half-pressing the shutter release button? How do the pros do it? I think it is a drawback in an otherwise excellent lens. 

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I know what you are saying, but to be clear for others so they won't be confused, your lens has to have AF enabled. As Demetrius pointed out, "Lens electronic MF" has to be set to "One shot-->enabled" if you want to fine tune with manual focus override (MFO). It's in AF menu item 4 on the R5 and R6 and AF menu item 6 on the R6 mark II. You don't mention which camera you are using (EDIT: Sorry, I missed the R6 reference), so I can only reference these three as they are the ones I use for stacking.

With that out of the way, stacking requires practice and some experimentation with camera settings, subject placement, and lighting. With the built in stacking of these cameras, contrast is very important to get the initial focus point. So if your subject has clutter behind the first point or is soft to begin with, it may be hard for the AF system to find an edge. I run into this on occasion when shooting flowers. Also, with this lens, aperture is important. It is pretty sharp wide open, but for best results, I've found it needs to be in the f/5- f/8 range. This will give you deeper DOF, a sharper slice, and eliminate any initial focus shift. TIP: When I run into the initial FP being soft I use a target that I made or my finger. By placing it just in front of my subject I get focus on it, then move my target and start the stack. I always use the 2 second timer to allow things to settle down whether I use a target or not. But usually, initial focus is not a problem.

Personally, I am not a fan of the built in stacking of these cameras and prefer dedicated software for both shooting and stacking. However, I do use it for simple stacks and  convenience when I don't want to tether my laptop to the camera when using Helicon software.

Newton

[rhirekat]

Thanks everyone who replied to my post. I tried out the settings suggested and it worked! Thanks again. Here is the image I made  with suggested settings. Stacked in Zerene stacker.