XT2 Focus peaking in Manual mode

[miguel]

I must confess to knowing nothing about focus peaking so I set up my XT2 with peaking in Red - low.

 

With a 35mm f2 lens attached and f2 selected, I noticed that the area shown in Red that is supposed to be in focus was greatly exaggerated when compared to the image viewed on my monitor in photoshop.

 

Also the in focus area highlighted in Red did not change at all when I changed apertures to f16, is this normal? Does it only register Red at the max aperture of the lens?

 

Michael

[gkramer71]

When you change apertures the focus doesn't change, only the apparent focus. f16 gives you a greater depth of field then f2

[miguel]

Hi,

Thanks for the reply but mine does not display a greater dof at smaller apertures.

 

I focussed on some lettering on a cereal packet on my table. At f2 or f16 the Red peaking colour does not change at all.

 

If you have an XT2 could you please try that for me.

 

Many thanks

Michael

[Adam Woodhouse]

I have only played with it a little bit (will play with it more when my Rokinon FishEye arrives tomorrow), but have found that it is finicky and takes practice to learn how it works.  I believe the visual marker we see when moving the focus ring indicates the front of the Depth of Field (DoF).  So the part in focus should be (approx) what is immediately behind the indicator.  At least that is what I recall when I used it last.  If you are at a small aperture, then the DoF results will be greater (naturally) but the focus peek indicator is still the same regardless of F-stop.  It would be pretty slick if the focus assist changed with the aperture to give us an area of focus to expect (or illustrate the expected DoF) .. but alas ... do any mirrorless cameras do that currently?  I know the Sony and Lecia have a pretty slick manual focus peeking feature, but I've never used one personally.

[miguel]

Hi Adam,

 

I am confused with this problem.

If the part in focus is immediately behind the indicator, is this the dof wide open or at F16?

When I use the 35mm lens focussed at about 15 feet the area in red extends to infinity.

 

I would be very interested in anything else you can clarify on this subject.

 

The main reasin I wish to use this function is to verify that the focus point selected by the af-l button

in manual focus mode is accurate

 

Regards

Michael

[Adam Woodhouse]

I did a bit of testing this evening.  I found that regardless of the F stop, the focus indicator when in manual focus does not change in size.   So I tested a shot @ F2.8 and F11.  What I found was the focus indicator seems to show where centre of the DoF (or what is in focus) will be.  I shot a piece of paper that had text on it from top to bottom and shot the text in the middle with the camera being approx 45 degrees to the paper.  So the area of focus (or DoF) was very obivous.  And when I shot it at F11, the area in front of and behind the manual focus assist line was pretty evenly in focus.

This help?

[miguel]

Hi Adam,

 

Thanks for trying this out.

I too will do a similar check.

 

It would work better for to identify the actual focus point if the sensitivity could be reduced further

than the Low setting.

 

Regards

Michael

[Adam Woodhouse]

I have never understood what the difference was between HIGH and LOW in the manual focus assist settings.

[Rand47]

Low is supposedly "lower sensitivity" ergo, "tighter" focus indication. High will show "more stuff" in red, but is less precise.

I agree with you that focus peaking on High doesn't seem to make much sense. I've yet to find a use-case for it.

 

As for DOF, once you have you focus selected via peaking, use the DOF preview (I have mine mapped to the front button) to check the depth things in acceptable focus. This's actually works pretty well.

 

Rand