File request: SD14 Full Spectrum X3F

Hoping that somebody, somewhere, may have a Full Spectrum X3F with a custom white balance taken off vegetation... or anything IR reflective. And be willing to share it!

** I recall (but possibly incorrectly) that the SD14 can capture a custom IR WB off vegetation, the only Foveon camera to do so... ? **

I'm interested in Full Spectrum (FS), NIR and Infrared but solely for the aesthetic e.g. I'm not the slightest bit interested in imitating Aerochrome film. Shooting FS with the SD1M means capturing a Custom WB off an 18% grey card and whilst this suppresses the influx of IR, the grey card isn't IR reflective, thus the IR 'effect' is merely neutralised.

An SD14 FS image/X3F will detail the RAW channel gain and matrices, and I'm hoping to transpose them to work with my SD1M. Fingers crossed.

tagscuderia wrote:

Hoping that somebody, somewhere, may have a Full Spectrum X3F with a custom white balance taken off vegetation... or anything IR reflective. And be willing to share it!

** I recall (but possibly incorrectly) that the SD14 can capture a custom IR WB off vegetation, the only Foveon camera to do so... ? **

I'm interested in Full Spectrum (FS), NIR and Infrared but solely for the aesthetic e.g. I'm not the slightest bit interested in imitating Aerochrome film. Shooting FS with the SD1M means capturing a Custom WB off an 18% grey card and whilst this suppresses the influx of IR, the grey card isn't IR reflective, thus the IR 'effect' is merely neutralised.

An SD14 FS image/X3F will detail the RAW channel gain and matrices, and I'm hoping to transpose them to work with my SD1M. Fingers crossed.

I searched my HD but found no such SD14 X3Fs, Tom, i.e. no Custom WB.

I can try it with my SD15 if that would help . .. nice and sunny today ... let me know.

xpatUSA wrote:

I searched my HD but found no such SD14 X3Fs, Tom, i.e. no Custom WB.

Thanks for looking Ted.

I can try it with my SD15 if that would help . .. nice and sunny today ... let me know.

If you don’t mind, that’d be great thank you! Custom WB off grass or other vegetation please.

tagscuderia wrote:

xpatUSA wrote:

I searched my HD but found no such SD14 X3Fs, Tom, i.e. no Custom WB.

Thanks for looking Ted.

I can try it with my SD15 if that would help . .. nice and sunny today ... let me know.

If you don’t mind, that’d be great thank you! Custom WB off grass or other vegetation please.

Already done, Boss!

http://kronometric.org/phot/post/dpr/Tom/

xpatUSA wrote:

Already done, Boss!

Fantastic!! Thanks Ted:

SD1M -cCustomWBGain: 1.320313 ; 1 ; 0.6445313

SD15 -cCustomWBGain: 0.996094 ; 1.25391 ; 1.48047

That's my first point of interest, and it's quite telling! Heading out now so will have to analyse the matrices later, but I'm optimistic just from the RAW channel gain.

P.S. thanks also for extracting the metadata, much appreciated 

I'd still very much like to inspect an SD14 X3F, no AFE and it'd be interesting to see the differences! So if anybody can help out...

Cheers all,

Unfortunately I can't correlate the SD15's custom matrix with the SD1M, I'm going to guess that it's the AFE so again, if anybody has a relevant SD14/F13 X3F it'd be greatly appreciated!

What I'm interested in:

SD1M CustomWBGain:1.320313;1;0.6445313

CustomCCMatrix:

R=2.875;-1.71875; 0.9921875

G=-3.15625; 3.851563;-4.648438

B= 1.28125;-1.132813; 4.65625

SD15 CustomWBGain:0.996094;1.25391;1.48047

CustomCCMatrix:

R=3.42188;-2;1.01563

G=-3.375;4.32813;-3.99219

B=0.953125;-1.32813;3.97656

Differences between the 2 were expected and wanted of course, with the SD1M CustomWB captured from a non IR reflective grey card vs the SD15's against vegetation, but the 2 don't play well... at all, in any combination.

Why do I think that it may be possible in the first place?* More hope than anything, but Foveon have published repeatable spectral responses, so it's possible that they haven't significantly altered the photodiode depth between generations. I'll have to compare Sunlight WBGain from F13 and F20 sensors to corroborate that though (possibly should have started there!!).

*WBGain is applied after the conversion to RGB, with Merrill RAW data already being RGB, so that is one less headache! And the gain won't be interchangeable of course without some modification.

It's nice (?) to see that SIGMA have been using the same noise reduction filters from 2007 to present day

Bilateral and anisotropic diffusion.

Fool's errand: the SD14 uses a WB correction matrix, no WBGain. CamToXYZ_Flash matrix follows so the chances of being able to transpose between the 2 cameras, well... it's beyond me

Shame because I'd love to be able to have my SD1M render a la the SD14 for natural light photography too, ach well.

tagscuderia wrote:

Fool's errand: the SD14 uses a WB correction matrix, no WBGain. CamToXYZ_Flash matrix follows so the chances of being able to transpose between the 2 cameras, well... it's beyond me

Sad to hear.

A point or three:

The transform from XYZ to sRGB is well known, if that helps. In other words, you could easily derive a cam-to-RGB matrix.

By the way, the WB correction follows the camtoXYZ, not the other way around, AFAIK. In other words, I think you must have XYZ values before applying an XYZ correction matrix.

The SD15 is no different to the SD14 when shot at 100 ISO - as far as the AFE is concerned.

Shame because I'd love to be able to have my SD1M render a la the SD14 for natural light photography too, ach well.

So you like a green cast, eh? Just kidding ...