The dreaded DOF scale international issue.

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M4streetshooter

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Ok, first off ... We can safely assume that this forum has many members that understand RF cameras. They also understand about DOF scales and how to use them. Many also use the X100.

So, if you use a DOF calculator, set to 23mm (22-24 will work), you will find that the scale in the camera is off.
It's off very bad on the close end of hyperfocal distance.

It appears that Fuji used a 35mm to design the scale.
Of course we all know that's just wrong.

Does this bother anyone or should I just drink another shot of single malt.
 
Are you taking into account that it has a crop factor of about 1.5X?

I have E-510 (4/3s) with a 2X crop factor. The dof is about double what it is on a 135mm camera using the same focal length and aperture.

Go here. http://www.dofmaster.com/dofjs.html Compare the 23mm lens with 35mm and see if the scale is closer with the crop factor added.
 
It's not about the crop factor. Any calculator will instruct you to use the actual focal length on the camera. Every other camera works right, the X100 scale is off.
Use the X1 as the sensor, put 23mm as the lens... compare to the scale in the camera...

I'm a streetshooter, this is an issue for me.
Set the focus distance anywhere you like, compare to the calculator and you'll see what's wrong.
 
M4streetshooter said:
It's not about the crop factor. Any calculator will instruct you to use the actual focal length on the camera. Every other camera works right, the X100 scale is off.
Use the X1 as the sensor, put 23mm as the lens... compare to the scale in the camera...
Click to expand...

In the end it's just that the camera maker took a decision what they consider the acceptable circle of confusion, and that's why the camera shows what it shows. I don't have an X100 here; what does the camera show, say, as hyperfocal distance for f/8?

DOF Master says it's 3.30 m, based on a Circle of Confusion of 0.02mm. The X100 has a pixel pitch of about 5.5 µm, meaning that this CoC would already covers four pixels wide and four pixels high. So it gets rather mushy. If you set the distance to those 3.30 m, what is one pixel at 3.30 m gets mushed into four pixels at infinity. If you set your standards of acceptable sharpness higher so that unsharpness within depth of field should, for example, never be larger than one sensor pixel, you have to calculate instead with a less generous CoC of 0.0055mm (the pixel pitch), which gets you a much stricter hyperfocal distance of 12.05 m at f/8.

Now how is this an international issue?
 
X100: f/16 6 feet to infinity
DOF program: 2.9 feet to infinity

X100: f/8 12 or 13 feet to infinity
DOF program: 5.8 feet to infinity

X100: f/4 25 feet to infinity
DOF program: 11.8 feet to infinity

I do understand a certain margin of error for being conservative.
Look above...that's a heck of a margin!

I have tested this, had prints made... Fuji got it wrong.
 
Last edited:
M4streetshooter said:
I do understand a certain margin of error for being conservative.
Look above...that's a heck of a margin!

I have tested this, had prints made... Fuji got it wrong.
Click to expand...

I don't think they "got it wrong", they're just catering to pixel peepers' ideas of sharpness. Looks like they calculated with a circle of confusion around 0.01 µm.

Now you can either order bigger prints and enjoy that they still look sharp, or you can get used to that in order to get prints that are acceptably sharp to you, you have twice as much margin as the camera suggests.

Still unclear how that's an "international" issue though.
 
Clearly, the difference between the figures calculated by Fuji and the figures calculated by a program on the internet is so large that - if standing at a frontier and pointing the camera in a particular direction - the wrong country can be in focus!!! Hence, it is an international issue . . errmmmm, I could be wrong (I usually am).
 
It's not just international, it's multicultural.

I used the same dof settings on the Nex5 and an X1.
So why would Fuji assume it's ok to make a scale that's off.
At f16, I have 16 x 20 prints that are great from around 3' to infinity.
Maybe I just don't see the Forrest for the Trees but this camera is no different than any other when it comes to dof.
 
As I always use a more stringent circle of confusion than the manufacturer's recommended CofC, I applaud Fuji decision. Maybe they figure that the lens is so good that everyone will want to make 20x24 inch prints and will want the tighter DOF limits.
 
Look at it this way.... You figure you need from around 6' to infinity for a shoot...
The camera says use f16.....
The light is slipping....
You really need f8 to get your dof...
That's 2 stops here in Philly...
 
More seriously, the whole thing depends on what you do with the recorded-image. In the old old old days the calculation would have assumed contact prints from a sheet or plate, while acceptable enlargement has varied depending on the quality of film and the enlarging tools available. Now with digital you can zoom in hugely on your monitor, or crop a small piece of the scene with ease - it is not unreasonable for the acceptable circle-of-confusion to be reduced in such circumstances, as so often throughout photographic history.
 
M4streetshooter said:
Look at it this way.... You figure you need from around 6' to infinity for a shoot...
The camera says use f16.....
The light is slipping....
You really need f8 to get your dof...
Click to expand...

...and you figure your camera's standards are higher than yours because you don't do pixel peeping...
...so when the camera suggests f16 you know that you'll still be happy at f8...

Everybody is happy. Problem solved! Cheers!
 
Yessir! Scotch will do that.
I just find it hard to believe the Fuji engineers planned this great mistake proof feature but couldn't get auto iso in the iso menu.....
Nah.... Sorry, ain't buying it...
 
If you put 35mm and X100 in to DOF Master you get what the X100 shows. Fuji just used the wrong numbers. In practice, what this means is, that if you work to the Fuji DOF scale you will be well within the zone of acceptable focus. If you want to be OCD (even slightly) about it then just note down the hyperfocal distance for your most commonly used f stops and set the focus to that distance in manual focus and you are sorted.
 
Thanks Gid..... I just see it as an unacceptable mistake.
I may be the only one upset about this and that probably means more that the issue at hand.
If Leica did this....hmmmmm worlds would collide.
 
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