I redid the testing of the previous post with an R72 filter in front of the lens. This filter blocks visible light, passing IR with a nominal corner wavelength of 720 nm. For the record, here’s the test protocol. I mounted the Coastal Optical 60mm f/4 UV-Vis-IR Apo Macro lens (hereafter called the CO 60) to… [Read More]
Coastal Optical 60mm MTF in mixed IR & visible light
I mounted the Coastal Optical 60mm f/4 UV-Vis-IR Apo Macro lens (hereafter called the CO 60) to the LifePixel-modified Sony alpha 7. The LifePixel filter absorption curve is “Super Color”. I mounted a RRS L-plate, clipped it in landscape orientation into an Arca Swiss C1 head which was attached to a set of RRS TVC-44 legs…. [Read More]
IR photography with the Sony a7 & CO 60mm f/4
Yesterday I went for a walk near my house with the LifePixel-modified alpha 7 and the Coastal Optical 60mm f/4 lens. No tripod. As an informal flare test, I shot into the sun: The above image is a ten-exposure stitch, with the camera held in portrait orientation, and a single row. I consider this… [Read More]
One thousand and one
I just noticed that yesterday’s post was my 1000th in this blog. It’s been a labor of love, and, although sometimes it has consumed more of my time and energy than I would have liked, I’ve enjoyed it immensely. I hope you have, too. Thanks to all you readers out there! Jim
Sharp Infrared Images
From the mailbag: I was pleased to see a posting on your site regarding the use of the CO60/4 for IR. I have been using the Zeiss 25/2.8 ZF-IR lens for my 830nm conversion and have recently been considering either the 50/1.4 ZF-IR or the CO60/4. If money weren’t a consideration then there would be… [Read More]
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