![]() Now, should there be some evidence of the visibly fluorescent blue-cyan fibers and dust on the flower which is so easily seen in later photo sets? Maybe, but I'm thinking that the reflected UV and emitted IR has possibly overwhelmed that. The next reflected UV photo set better shows the UV-signature of this flower without resorting to channel extractions. The emitted IR has washed it out a bit in the 3-channel photo. The flower shows a slightly UV-absorbing center. The raw Red channel doesn't show much unless pushed because the count and breadth of the red is low compared to the blue. Raw channel extractions in monochrome are also shown as further support for the separation of the reflected UV and emitted IR. That fits what we know about reflection and fluorescence (typically narrower, peaked). ![]() You can see a broad range of reflected UV in the blue and a narrow range of emitted IR in the red. We would expect the Foveon sensor to record the relatively shorter reflected UV light on the top blue layer and the relatively longer emitted IR light on the bottom red layer. See Infrared Fluorescence, Visible Fluorescence. This photo set acts as a control against which the primary fluorescence sets may be compared. Under UV illumination from the 365nm UV-Led, this U330 filter should capture both the UV reflected off the subject and any IR emitted from the subject. LOOK FOR: the adjusted version following each monochrome raw channel photo. And IR fluorescence of the flower petals is recorded in the Red channel. Blue-cyan fluorescent fibers show up in the Green channel. UV is very strong in the Blue layer as evidenced by the floral UV-signature recorded there. I think that this set of SD14 photos definitely illustrates the possibilities of Foveon separation of wavelengths well. Control Set: UV Reflection + IR Emission.(Of course, an adjusted raw comp should be be taken as accurate.) So I have supplied a "pushed" raw composite which better shows the raw recording in its non-white-balanced colours. ![]() Purpose of Showing Adjusted Raw Composite: In low light there is often not much to see in a raw composite even after application of the usual contrast adjustments following demosaicing. Images were cropped and resized in Photo Mechanic and labeled in Photoshop Elements 11. Data along the y-axis is linear (actual count, binned at 1/64 interval). EV0 is based on the SD14's data range so that histograms are easier to compare. ![]() RD settings included Gamma 2.2 and Autoscale so that the demosaiced images are visible. Software: The raw composites and r aw histograms were created with Raw Digger. ![]()
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