bobfriedman Posted February 29, 2020 Share Posted February 29, 2020 is the IRIX 11mm f/4 Firefly Lens IR-capable? Link to comment
nfoto Posted February 29, 2020 Share Posted February 29, 2020 Not tried it, but my guess is that it might be showing a hot spot. Most modern ultra-wide lenses do. Link to comment
ulf Posted February 29, 2020 Share Posted February 29, 2020 Sometimes hotspots are aperture related. I don't have the Irix 11mm, only the Irix 15mm/2.8.I tried how it behaved in IR.My lens start to show a hotspot, visible on the camera's monitor after the shot, between f/5.6 and F/8. Tested with both 720nm and 850nm long-pass filters, rear mounted with grey-tak. Link to comment
nfoto Posted February 29, 2020 Share Posted February 29, 2020 My impression is that the camera also enters the equation as it were. On my modified Z6, most native Z lenses show very pronounced IR hot spots no matter what filter is used. Only the 50/1.8 S is OK. Fortunately, the old IR workhorses continue to be acceptable even on this new camera system. In particular the mid '70s 28-45mm f/4.5 Zoom-Nikkor is amazing good. Link to comment
Cadmium Posted February 29, 2020 Share Posted February 29, 2020 I guess the IRIX 11mm f/4 Firefly is not a circular fisheye?I read that the Nikon 10.5mm can be modified to be a circular fish on a full frame camera by cutting the hood off. I have not seen an IR hot spot with the 10.5mm used with DX.Also that the Samyang/Rokinon 8mm Fisheye CS II has a removable hood, which works the same for circular fish mode on full frame, I understand, but I don't have experience with that, nor with possible hot spot. Link to comment
bobfriedman Posted March 1, 2020 Author Share Posted March 1, 2020 I guess the IRIX 11mm f/4 Firefly is not a circular fisheye? this is a rectilinear lens. Link to comment
bobfriedman Posted March 2, 2020 Author Share Posted March 2, 2020 wow.. you finally did it. you need to make this a separate thread Link to comment
Cadmium Posted March 3, 2020 Share Posted March 3, 2020 wow.. you finally did it. you need to make this a separate thread OK... Link to comment
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now