uniwb file for x-h1?

Started 4 months ago | Discussions thread
OP mainoo Regular Member • Posts: 117
Re: uniwb file for x-h1?

RetiringGuy wrote:


Use RawDigger and the blinking exposure warnings of your X-H1 to find out how much exposure compensation is needed so that none of the colour channels are being limited (overloaded).

Yes the technique will only get you to within 1/3 stop of the critical exposure but all you need is the camera and a white/grey target

You will need a lens with an aperture ring and a photographic target scene where the illumination DOES NOT change and the brightest part of the scene is basically as grey/white as you can get it.

Make sure your camera does not move during the testing.

Select an appropriate ISO speed for your normal work.

Select a Film simulation for your normal work.

Select an aperture in the middle of its available range.

Switch on the blinkies and adjust the shutter speed so that the blinkies are either just starting or just stopping. Make a note of the shutter speed and aperture value.

Take a shot.

Adjust either the shutter speed OR aperture up AND down in 1/3 stop steps while keeping the other (aperture or shutter speed) the same as you started with and take a shot at each setting combination. (i.e. take shots at 1/3 stop increments above and below the onset of the blinkies.

Look at your RAW shots in RawDigger and select the most exposed shot that does not have any colour chanel limiting. Look at the shutter speed and aperture values to see how many 1/3 stop steps it is above or below the point of the onset of the blinkies.

For that ISO and film simulation you now know how many 1/3 stop steps you need to adjust your exposure above or below the onset of blinkies in order not to overload any of the colour channels and you can dial that into the Exposure Compensation adjustment.

I normally use ISO 200 and nothing else but its quite probable that the results won't change much for a reasonable range of ISO but will probably change with change of film simulation.

Hope this helps.


Thank you very much for your suggestion. I will indeed be doing something like this if I can't get uniwb to work (or if I want a jpeg as well) with slight modifications. I mainly shoot people wide open so I will use that as my aperture. I will test at iso 200, 800 and 1600. I'll start with astia (liked its look as a film).

Thanks again.

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