Poll: achieving focus in wide angle shots

I am curious of how other users focus the camera for wide angle shots using a dome or a water contact optic

Feel free to elaborate on why you use that option

For over/under with subjects greater than 2m away I tape the focus in a single position. If things aren't moving, single point, if they are I will often us Auto Area continuous as my eyes aren't good enough to check focus until it's on a monitor. Nikon Z50.

I guess I want to elaborate now why I asked the question. As a foreword unless I am shooting moving dolphins I use single AF for wide angle including slow moving subjects

I have spoken to many people and they all do the same on any format but from time to time someone comes up with the conversation of why tracking is important or caf so I am wondering why is it important to some and not to others?

12 hours ago, Interceptor121 said:

I guess I want to elaborate now why I asked the question. As a foreword unless I am shooting moving dolphins I use single AF for wide angle including slow moving subjects

I have spoken to many people and they all do the same on any format but from time to time someone comes up with the conversation of why tracking is important or caf so I am wondering why is it important to some and not to others?

I think giving a vote does not mean that this kind of focus is the only one that works reasonably, but here comes the rationale for my vote:

The reason for me not to use MF is similar to Pete, my visibility is just not good enough to judge correct focus in the viewfinder. I use C-AF&tracking because it works well on my camera (EM1-II) and I find it is useful for CFWA, when the object in the foreground is not in the center. This way I do not need to to shift the focus point away from the center. I presume the S-AF people just focus S-AF with the object in the middle and then they re-frame without additional focusing and this works also well?

Wolfgang

Of course, which AF mode you use depends primarily on which AF system you have....

In my case, I have used AF-C 3D AF for pretty much everything since the D810. It is so good, there is no real reason to change. Continuous AF (along with back button activation) allows easy recomposition with wide angle images and compensates for any lack of (my) stability in the water.

 

4 hours ago, Architeuthis said:

I presume the S-AF people just focus S-AF with the object in the middle and then they re-frame without additional focusing and this works also well?

For me it depends of the situation. If its a non moving subject I take the time to move the AF-point to it. Otherwise I act as you said. The first method is safer but they both work well.

Your remark that you use C-AF&tracking on your EM1II is interesting for me as I use an EM5III and always avoided C-AF+tracking because of its reputation in reviews. The autofocus algorithm of the 5III seems to be slightly better than that in the 1II so I will give it a try. Here I have a question, did you increase the C-AF sensitivity (A1) of your camera?

2 hours ago, Floris Bennema said:

For me it depends of the situation. If its a non moving subject I take the time to move the AF-point to it. Otherwise I act as you said. The first method is safer but they both work well.

Your remark that you use C-AF&tracking on your EM1II is interesting for me as I use an EM5III and always avoided C-AF+tracking because of its reputation in reviews. The autofocus algorithm of the 5III seems to be slightly better than that in the 1II so I will give it a try. Here I have a question, did you increase the C-AF sensitivity (A1) of your camera?

C-AF&tracking works very reliable for WA, even with adapted Canon 8-15 and Tokina 10-17 lenses (it works so-so for macro and is very difficult to use with 60mm+CMC-1 (or with the adapted Canon 100mm IS macro, that I also have).

I have mode to "s" (smallest spot); sensitivity +/-0; and face priority off...

I faintly remember that I have varied "sensitivity" and more sensitivity resulted in faster reaction, but more prone to loose the object and less sensitivity the opposite...

Wolfgang

6 minutes ago, Architeuthis said:

C-AF&tracking works very reliable for WA, even with adapted Canon 8-15 and Tokina 10-17 lenses (it works so-so for macro and is very difficult to use with 60mm+CMC-1 (or with the adapted Canon 100mm IS macro, that I also have).

I have mode to "s" (smallest spot); sensitivity +/-0; and face priority off...

I faintly remember that I have varied "sensitivity" and more sensitivity resulted in faster reaction, but more prone to loose the object and less sensitivity the opposite...

 

Wolfgang

A movement of 1 meter of the target results in change of focus of few cm behind a dome. So even if the subject moved it won't make a major difference unless you are close range. In addition the depth of field distribution behind a dome shifts considerably backwards.

When you are at close range if you want to have everything in focus in the frame you will have so much depth of field that everything will be in focus

In addition you can bump focus focus first and focus again with single AF for this reason unless you have a really fast moving target most people do not use CAF

I guess that boils down to preference but people that I know that have the same D850 of another poster here don't use CAF unless shooting fast moving fish where the fish is the clear subject if that makes sense

I also should ad that I do not have any focus gear for the WA lenses (just zoomgears), so MF is not possible, even if it would be desired...

"In addition you can bump focus focus first and focus again with single AF for this reason unless you have a really fast moving target most people do not use CAF": the same is essentially possible with C-AF&tracking, you just have the additional option to continuously to push the focus knob for reframing/following an object...

Wolfgang

1 hour ago, Architeuthis said:

C-AF&tracking works very reliable for WA, even with adapted Canon 8-15 and Tokina 10-17 lenses (it works so-so for macro and is very difficult to use with 60mm+CMC-1 (or with the adapted Canon 100mm IS macro, that I also have).

I have mode to "s" (smallest spot); sensitivity +/-0; and face priority off...

I faintly remember that I have varied "sensitivity" and more sensitivity resulted in faster reaction, but more prone to loose the object and less sensitivity the opposite...

 

Wolfgang

Thanks 

1 hour ago, Architeuthis said:

I also should ad that I do not have any focus gear for the WA lenses (just zoomgears), so MF is not possible, even if it would be desired...

"In addition you can bump focus focus first and focus again with single AF for this reason unless you have a really fast moving target most people do not use CAF": the same is essentially possible with C-AF&tracking, you just have the additional option to continuously to push the focus knob for reframing/following an object...

 

Wolfgang

No it is not the same. CAF moves the lens based on what it think it will happen or land. It may have unpredictable results when the focus motor steps are set for that the camera thinks it will happen on land or with a flat port

The camera specifically may go hunting when it predicts focus. With single AF there is no prediction

Now this may work totally fine in some circumstances it may be required (the dolphin case) 

Looking at that case how many shots do you get fully in focus when you have a fast moving target with CAF? If the answer is 100% than that system could be trusted even if not required if instead you get issues than I would not trust that system by default and would use bump focus

Single AF is not manual focus is single AF they are very different.

Single AF is not based on the camera thinking where things will be is based on where things are at the moment you half press the shutter

I just use the same method I normally use above water, with a Nikon DSLR (D810, D850), or Nikon ML (Z9).   That is, back button focus with the camera set to use 3D Tracking.   Basically it's a single point that is supposed to grab onto whatever object you put it on and keep tracking it as long as you hold the AF-ON button down.    For wide-angle, where I'm shooting from 14mm to 30mm at F8 minimum aperture, I have so much depth of field that focus isn't too critical.  I normally don't shoot moving animals though, but I would certainly try to use the same method as 3D Tracking is supposed to do exactly that - track moving objects in 3d.

So far, subject detection underwater has not worked for me, so I normally turn it off.