I few years ago I asked Ed Sinofsky of PhotoGlow (photoglow.com) to make me a panel similar to Spike-a-Flat but with a spectrum that included at least part of the near-IR so that I could make all my flats from B to Ic easily. I was very pleased with the results, even lighting, remotely controlled with a Spike-a-Flat controller resulting in what IMO are really good flats.
I could not advertise this neat new B-to-Ic flat panel. Ed made it as an experiment and due to his ongoing obligations to Spike-a-Flat he could not offer such panels for general sale. That obligation has ended and Ed has signaled that he is willing to make panels up to 30"x30". I ordered an 18'x18". I am not sure how the pricing would be structured, but if anyone is interested I think Ed would be happy to make one for you. I have some spectra and light distribution pictures of my panel and would be glad to forward that information, although I suspect Ed would do the same.
My panel: white light LEDs on 2 sides and 850 nm LEDs on the other 2 sides. In essence a spike-a-flat on Ic steroids. I wonder about a flat panel with an array of LEDs each centered on a Johnson-Cousins filter spectrum peak.
Ed Wiley (the other Ed)
Hello! Are these LED panels or are they electroluminescence? From your comments, I presumed the former.
It sounds like you've found the Ic coverage to be good. When I looked at IR LEDs, the spectrum always seemed to high and the width to narrow in order to get good coverage at Ic = 806 nm for photometry.
I would be interested in seeing the spectra and light distribution flats you've obtained. Best regards.
Mike
Mike,
Description of my panel from Ed Sinofsky: It has white light LEDs on 2 sides and 850 nm LEDs on the other 2 sides. This unit for Ed [me] is 18” x 18”
I can't seem to upload the pictures Ed sent me, so I suggest that you contact him directly or me off-forum. The white light LEDs show the usual dip at about 475nm that seems to be typical of white LEDs, so the spectral coverage is not uniform. I suspect that could be improved with addition of other LEDs but it seems "good enough" at the amateur level for now. The 850nm spectrum appears broad with a peak at around 840 nm. The Y-axis is in intensity units (max 10) and ranges from 4 at 800 and 865nm with a more-or-less normal distribution that is not peaky (intensity level =7 at 820 and 852nm). If you consider the intensity scale, at 805 nm it scores 5/10 and going up towards the peak that is at around 835nm. I was especially pleased with the results in Ic. And my original motivation in having that first panel made by Ed S was my frustration in trying to extract a decent Ic flat out of an EL panel and my desire to avoid twilight flats.
I suspect one can do much more with LED panels, I consider mine to be first generation + Ic coverage. I am now between rigs, having taken down my Edge and in the process of installing another rig. I do have flats I can share from my old rig, we can discuss that off-forum.
Ed Wiley