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Sigma sd Quattro false color


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A few random early morning shots with the sd Quattro.

Sigma sd Quattro - dust protector removed + Sigma 30mm/1.4 EX DC HSM + Hoya X1 / FLD filter stack

 

http://radium.zenfolio.com/img/s/v-3/p2870961028-4.jpg

 

http://radium.zenfolio.com/img/s/v-3/p2870949088-4.jpg

 

http://radium.zenfolio.com/img/s/v-3/p2870972667-4.jpg

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This system works really well for that deep magenta color. And gives those yellow tones I've read about. Some nice color variation to add interest. Cool.

 

Review for me please what are the Hoya X1 /FLD filters you used? I am not familiar with those. :rolleyes: Thanks.

They seem to be a good combo for the Foveon sensor. Wonder how they would work on a converted Bayer sensor??

 

I think I would raise the midtones just a bit on the last one. Looks a bit dark?

 

It's funny, isn't it, how these images seem quite natural to us who love shooting alternate wavelengths. :lol: B) B)

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Thanks Andrea! I don't have a converted Bayer sensor camera to test the X1, but so far it only produces green images on my unconverted Olympus M1.

 

As you may know, the foveon sensor produces an overabundance of 'red'. For EIR-like colors, the camera needs to be color balanced, either through the CWB settings, or with the use of an external filter. Once that's done, the overall reddish cast disappears, with more defined separation between colors.

 

No filter is required on older Sigma 'SD' models, or 1st generation FS-converted 'DP' models. All that's needed, is to set a CWB capture on any grey surface and you're good to go.

 

Unfortunately, CWB capture is difficult to impossible, on later Sigma models, and is why I've resorted to the Hoya X1 green filter on my current sd Quattro.

 

This publication mentioned the use of the Hoya X1 green filter, on the Sigma SD1 Merrill, as a way of digitally simulating the red/magenta hues of Kodak infrared EIR film, to record healthy foliage and vegetation, in a single exposure. http://www.mdpi.com/2313-433X/2/2/14/htm

From this, I decided to try a Hoya X1 stacked with a light magenta generic FLD filter, which seems to work well with sdQ.

 

The Hoya X1 comparison graph shows marginal IR sensitivity, but I have no idea if it slopes upward after 750nm.

Although the X0 green filter shows far better IR sensitivity, but it doesn't produce EIR colors.

http://host.tokinalens.com/pictures/F0000059-transmission.gif

 

 

sd Quattro (dust protector removed); No filter

http://radium.zenfolio.com/img/s/v-3/p2877129967-4.jpg

 

Same sd Quattro setup as above, with Hoya X1 + FLD filter stack.

http://radium.zenfolio.com/img/s/v-3/p2877129948-4.jpg

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Andy Perrin
This is quite interesting. I had never heard of the Foveon sensor. I love the idea of getting rid of the Bayer from the design.
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This is quite interesting. I had never heard of the Foveon sensor. I love the idea of getting rid of the Bayer from the design.

 

Hi Andy, Aside from higher resolution, the current Quattro sensor produces different results than the original 3-layer foveon sensor. For that reason, some foveon addicts seem to prefer the Merrill, and older Sigma models. Foveon sensors can do some things that Bayer-sensors can't do, but the opposite is also true.

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Gary, How do you feel these results compare with your "Sigma DP1x FS-conversion - no filter - SOOC" shots that you posted a while back?

I really liked those, although the resolution of that other model seemed a bit low. I guess the resolution on this Sigma sd Quattro camera is higher.

http://www.ultraviol...__fromsearch__1

 

I think the colors, especially in the pink, magenta hues are far better on the FS-DP1x. Those older Sigmas are easy to set a CWB, and a pleasure to use. Sadly, my current FS-DP1 has succumbed to the 'stuck lens' issue, which is common to these early models. The resolution is only 4.6 MP, but there is more detail information, than the standard Bayer-sensor. The Merrill was a big leap forward at 14.8 MP, while still retaining the 3-layer foveon design. Quattro added a forth layer to dramatically increase resolution, especially on the sd Quattro H @ 25.6 MP.

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