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GFX 100s erratic distance indicator


Borowiec
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I've had the 100S for a couple of weeks now but am having a lot of trouble using the depth of field scale, what the manual calls the Distance Indicator. Specifically, when I focus manually on a point and the white line under the distance scale at the bottom of the viewfinder shows a particular distance, if I then use auto-focus on that same point, about half the time the white line moves to a different number, often one quite far away, e.g. from 15ft to infinity. Also, often when I use auto-focus the white line is clearly in the wrong position: I will focus on something at 15ft and it will move to the 30ft mark. The only way to get it to show an accurate distance number is to auto-focus on a relatively near point, say 7ft, then gradually focus on further points, and eventually it will show an accurate distance. 

I have not only observed this in the field, with disastrous consequences for the depth of field in my photos, but have confirmed it with careful tests using a measuring tape. In short, the distance indicated by the white line is very inaccurate about half the time, and it is very inconsistent. I can focus on the same point multiple times and it will show wildly different distances.

Note that when I confirm the lens's focus by zooming in, the auto=focus point is always correct: the focus is working properly, it's the distance display that is not. This phenomenon is not a factor of the lens, as it happens with both the 30mm and the 45mm.

I have been through the manual and the menus countless times trying to see if I have something set incorrectly, to no avail. I did find a post from several years ago elsewhere on this forum about a similar thing happening with one of the X cameras, where someone wrote that Fuji was "working on it," but nothing else.

Am I doing something wrong or is this just a defect in the camera?

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The Distance Indicator in Fujifilm cameras is notoriously unreliable. It can behave quite erratic and is often off by 1-2m or so. With an APS-C X-mount camera at f5.6 it is less of an issue, but for a GFX100 it becomes useless. It was one of the (many) points why we decided to stay with our H6D setup.

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48 minutes ago, Borowiec said:

Thank you Herco, you have confirmed what I suspected. Now I have to decide if I want to keep the camera...

Perhaps you can make changes to your workflow when focusing? The 100S normally has good AF that doesn't require the Distance Indicator, unless you want to work with the hyper focal points (e.g. for landscape).

For portraits (as we do in our Studio) the AF in combination with eye-AF works reasonably well. However, like most Fujifilm cameras, there's a tendency towards front-focusing whereby the focus is on eye lashes instead of the pupil. That's usually only an issue with longer lenses at large apertures like the 110 at f2.

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Yes, I'm experimenting with various ways of controlling depth of field, because I photograph landscapes. I know the 100S focus is accurate, I just need to find a method to ensure that I have placed the depth of field where it needs to be. I'm trying different positions of the distance indicator relative to the infinity mark.

I've also tried using a depth of field phone app and a rangefinder to accurately measure distance (not a rangefinder camera, an actual rangefinder). This does work but it's very cumbersome.

And of course there's always focus stacking, which works brilliantly, but is also very cumbersome.

It's funny because when I used 6x9cm film for forty years, f11 on a 90mm lens gave me all the depth of field I needed, i.e. from 5 meters to infinity, but with a 45mm on the GFX 100S it's not possible to have that same depth at f11. I suppose the detail of the sensor requires a different definition of what is an acceptable circle of confusion. I may end up using f16, even though the lens isn't as sharp, due to diffraction.

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That's strange... I've quickly looked-up some tables and according to me the CoC of a 6x9 is 0.07 and for the GFX100 it should be 0.038 (same cropped MF sensor size as the Pentax 645Z). Using a 90mm at f11 on a 6x9 set at approx. 11m hyperfocal should result in a DoF from 5.3m to infinity. For the GFX using a 45mm at f11 set at approx.  5m hyperfocal results in a DoF of 3.2m to infinity. I've never heard of a different definition for an acceptable CoC before...

I can't understand why Fuji after all these years is still not able or willing to implement an accurate DoF calculator in their cameras. My H6D is accurate to the cm. Same for my wife's SL2... For typical landscape use (one of the GFX sweet spots) it's a must-have. 

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I think the difference is more a matter of perception, of what looks acceptable. That's why the 100S has two different settings for the depth of field scale. On 6x9 film I rarely made prints larger than 16"x20" and distant backgrounds looked sharp. With the 100S I can see that the background is not sharp when I look at a file 100% on screen, but it looks perfectly fine in a 17"x22" print. My concern is that I want the files to hold up for larger print sizes, which was never a concern with 6x9 film.

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