X-Pro2: Depth-Of-Field Scale, Film Format Basis vs. Pixel Basis, What's the difference?

[Wing0949]

X-Pro2: Depth-Of-Field Scale, Film Format Basis vs. Pixel Basis, What's the difference?

 

I've read what the difference is from the X-Pro2 Owner's Manual, but I still don't quite understand. Frankly, it's an extra option & setting which serves to confuse me a bit.. I've never heard or seen this option on any other camera until now, so not sure how to even use this really?  Is there really that big of difference between how your files will render depth of field for print versus on screen?

 

If somebody can shed some insight into this particular feature, thanks!

 

Here's a screen shot of the excerpt from the manual included in this post.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[flysurfer]

Pixel based is our usual DOF scale as we know it from previous X cameras. Of course, it's now adapted to the new sensor and its smaller pixel pitch.

 

Film format based corresponds to the DOF markings on Fuji's MF clutch lenses. This DOF scale about 4.5 stops less conservative and only recommended if you do not look too closely and don't print or display large.

 

Also see my article for images showing both scales while setting a hyperfocal distance: https://fujixsecrets.wordpress.com/2016/01/16/first-look-fujifilm-x-pro2/

Edited March 7, 2016 by flysurfer

[Wing0949]

Pixel based is our usual DOF scale as we know it from previous X cameras. Of course, it's now adapted to the new sensor and its smaller pixel pitch.

 

Film format based corresponds to the DOF markings on Fuji's MF clutch lenses. This DOF scale about 4.5 stops less conservative and only recommended if you do not look too closely and don't print or display large.

 

Also see my article for images showing both scales while setting a hyperfocal distance: https://fujixsecrets.wordpress.com/2016/01/16/first-look-fujifilm-x-pro2/

So, I guess it's just better to go with pixel based DOF scale for better dof accuracy.

[flysurfer]

So, I guess it's just better to go with pixel based DOF scale for better dof accuracy.

 

If that's possible, sure.

[andyfromboston]

DOF is the range of distances between which a small detail can be seen clearly. To figure this out you need to define "clearly" so you define a size for a "circle of confusion" which is the size of the detail you will see when looking at a print. Lens makers traditionally picked a print size and viewing distance (I forget what these numbers are) for this calculation. When you see a DOF scale on e.g. an old Nikkor lens, the DOF marks correspond to Nikon's calculations using those numbers. That's how "film former basis" works. When doing this for film, the amount of detail the film will capture is not accounted for in the calculation.

 

With digital people are in the bad habit of judging sharpness based on 100% magnification on a screen. Sensor resolution becomes a factor, which is why all those people who switched from a D700 to a D800 started hating on their old lenses. Pixel basis DOF is for 100% viewing, so the circle of confusion effectively becomes much smaller. You will have much tighter tolerances because you're looking at much higher magnification (as if you were using circle of confusion based on a huge print viewed at close distance) and sensor resolution will be a factor, so your pixel basis DOF on an X-Pro2 will not be the same as on an X-T1 (if they add the feature in future firmware).

[andyfromboston]

So I think the practical application is, use film format basis of you are planning moderately sized prints or web images, or pixel format if you care about 100% views or huge prints.

[flysurfer]

Of course, 100% viewing is becoming the norm with 5K and soon 8K displays becoming the norm. You don't even have to zoom in for it. In a few years, 24 MP resolution will be required to fill all pixels of a normal desktop screen. 

[Noel]

As stated above the two ranges are:

1) Film Format - based on typical a circle of confusion size required for viewing a 8x10 print at normal viewing distances.

2) Pixel Format - based on a circle of confusion size similar to that of the actual sensor pit size to compensate for pixel peeping at 100%.

 

Don't; get too hung up about this issue. It's one of these rabbit down the hole matters that is best left well alone. If you go chasing that rabbit its not long before you are conversing with the Mad Hatter and the March Hare about the intricacies of Scheimpflug calculations.

 

The film format range is approximately equivalent to the DOF markings on manual lenses. When you use these markings the same rule applies, the larger the print (or screen resolution) the narrower the DOF compared to the markings. Keep that in mind and the normal DOF techniques apply just as they did with film. I.e. stick it on f/5.6 focus on the nearest eye and everything from the tip of the nose to the back of the ear will be in focus for a headshot on a 8x10 print.