Fuji X100 Dynamic Range limitations

Allan

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Phoenix, Arizona
As a jpeg shooter, I'm struggling to understand the behavior of the Dynamic Range (contrast) settings. It strikes me as odd that at ISO 200 I can only select DR=100%. At ISO 400 I can select DR=100% or 200%. At ISO 800 I can select DR= 100%, 200%, or 400%.

Why should the sensitivity setting pose limitations on how much I can increase the DR?

I posted this question at the X100 Forum too Dynamic Range Settings - X100 Forum. I repeat it here, not knowing which forum will provide the answer.
 
the x100 uses the hardware based DR expansion seen in the F100fs and S100fs, it boost the iso to bring up the shadows basically so to get maximum benefit you need a higher ISO.
EXR sensors have a binning property where when shot half resolution one half is used for shadows and the other for highlights; in this you would need no ISO boost.
This is general Fuji EXR tech the X100 might have the pixel binning but I am not sure not having one....
 
This is general Fuji EXR tech the X100 might have the pixel binning but I am not sure not having one....

This is my first Fujifilm camera, so I'm unfamiliar with the esoteric terminology which only Fuji seems to use.

We are taught that proper exposure is achieved by "exposing to the right" as much as possible, short of blowing out any highlights. That accomplished, one then wants to spread out the histogram to the left as far as feasible, without blowing any shadow detail. I assume that this leftward expansion is what happens when increasing the Dynamic Range.

So what am I suppose to do on a bright sunny day, with ISO set at 200? The X100 will then only allow only DR=100%, with no option for expansion. It seems inappropriate to have to increase ISO to 800 so that I can set DR=400%. And what do those figures mean, anyway? Is the historgram at 400% really four stops broader than at 100%?
 
The dynamic range as Lili explained is equated to fstops...
so 100% is considered normal, 200% is 1 stop...400% is 2 stops.. It's the 1/2 double inverse square law that we as photographers have to live by...
 
You should also post your results...
I think this issue will be coming up more often in the future.
With your results and Lili's brain, we'll have a good answer when it does...
 
You should also post your results...
I think this issue will be coming up more often in the future.

This single exposure at ISO 800 was captured in RAW, then developed in-camera to vary the Dynamic Range. The left image is DR = 400%, the right image is DR = 100%. The corresponding histogram is shown below each image.

For a contrasty scene like this, it is clear that DR=400% will produce a good jpeg without clipping the highlights.

The lesson for us jpeg shooters might be that even on a bright sunny day we should select ISO 800, because with lower values of ISO the DR cannot be selected as 400%.



Screenshot2011-05-09at35828PM.png
 
If you're shooting jpegs and you trust the X100 to get it right, shoot with auto ISO and auto DR and watch the ISO values jump around. Its alarming at first, but damned if it doesn't work quite well. It'll jump up to iso 800 in the middle of the brightest sunniest day and you'll wonder why until you realize its the auto DR doing this. I was freaked out by it at first, but this camera is so good at higher iso that I've started trusting it and it does a really really good job. Lately I've been leaving the ISO and DR on auto and just playing with the shutter speed or aperture and, occasionally, the ND filter.

-Ray
 
If you're shooting jpegs and you trust the X100 to get it right, shoot with auto ISO and auto DR

I'm so new with the camera I had not got around to trying this. I'm going to try your "double auto" settings.

[edit] Okay, I set auto ISO and auto DR, and re-exposed the same shot as posted above. The camera selected ISO 200 (there was plenty of light, obviously), and DR=100%. Looking at the histogram, it shows hghlight clipping, as in the previous histogram above (right). So this "auto" method did not produce a desirable result for this scene.
 
I never did any formal testing to see how it would react - I just started seeing the ISO jumping around very unpredictably and asked somewhere about it. Was told it was a result of the auto DR. I just looked at a couple of shots I took last weekend in bright light with a lot of contrast and sure enough, ISO 800...

-Ray
 
If you're shooting jpegs and you trust the X100 to get it right, shoot with auto ISO and auto DR and watch the ISO values jump around. Its alarming at first, but damned if it doesn't work quite well. It'll jump up to iso 800 in the middle of the brightest sunniest day and you'll wonder why until you realize its the auto DR doing this. I was freaked out by it at first, but this camera is so good at higher iso that I've started trusting it and it does a really really good job. Lately I've been leaving the ISO and DR on auto and just playing with the shutter speed or aperture and, occasionally, the ND filter.

-Ray

Ray, thanks for the explanation. This erratic auto ISO behavior irritated me last Sunday, but now I understand. On sunny days I usually use aperture priority, auto iso 1600, often ND filter on (ND on/off assigned to the Fn button), min shutter speed 1/125.
 
I haven't tried auto ISO yet. I generally set the ISO and adjust it as needed, however I can see that this camera's abilities to use such a variety of high speeds so well could give a whole new meaning to auto ISO. I've pretty much decided to stick with the RAW to DNG mode because I just like it...but I can also see that jpegs can be a great and worthwhile alternative. I appreciate reading everyone's feedback very much.
 
I've pretty much decided to stick with the RAW to DNG mode because I just like it..

RAW to DNG mode? is this in camera or on computer? I've been using Adobe RAW converter to do this, as I'm beginning to think I don't like the amount of cyan in the fuji sky colours.

all the best
 
In the computer, sorry about that. I use Lightroom and convert the RAW to DNG while importing.

Meanwhile, I have to back track a bit... I am trying the jpegs along with the RAW again...this time in the Astia mode. I want to see how the different film modes work.
 
Snap! That's what I'm about to do - to see if I like the colour any better.
I've been using Adobe DNG converter to convert the raw files and then working on them in Aperture - it's an extra step, but not too arduous - I'm sure that Apple will include support for the files sometime in the next decade or so :dash2:
 
;) I remember waiting for Aperture. I know it's a great program, but when it gave me some serious issues with my X1 files...I migrated. Sounds as though you have a good work around, Jono.(y)
 
Actually, they have been better since version 3. I still far prefer their local adjustments to Lightroom, especially the cloning (we have a LOT of telegraph poles around us!).
 
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