Just published the CHSOS Infrared Photography Lenses Database. Anybody is welcomed to ship their lenses to be tested for infrared photography and be added to the database. Also everybody with a Nikon DSLR camera modified for Infrared is welcomed to contribute to this database by doing a similar test and providing the photos to be posted here.
Lenses show hotspots when shooting infrared photography. Hotspots are caused by the coatings inside the lens barrel and the lens elements or by the interaction between the lens elements and the imaging sensor. Hotspots become more apparent at higher aperture numbers, while often disappear at the lowest numbers. Depending on the application and the task the infrared photo should be taken, low or high aperture numbers could be necessary. For the specific needs of infrared photography for art documentation it is useful to have detailed information on lenses behavior at different aperture numbers. This database tests only Nikon lenses.
Hello Antonino
It’s a great idea to create a database, i could colaborate with, I have diferent Nikon lens as you have.
My problem is that I don´t have yet the IAC target, but I can use the color checker instance.
Just send me the instruction, and I will.
Ups! I forgot to say you, that I have a Nikon D90 and Peca set filter
Saludos desde Chile
Hi Carolina, thank you so much. Ideally, I would prefer to test the lenses with the Nikon D800. Indeed, the hotspots could depend also on the interaction with the camera’s detector, In any case, I would be relly happy if you could do the test with your Nikon IR modified camera. That data would provide useful information, in any case, and I’ll be happy to add them to the database. The test is pretty easy. Just use a black cardboard and white one, as you see in my photos. You don’t have to use the AIC target, you can use any color checker with a ruler. Shoot photos starting from the lower aperture and moving to the higher aperture number. Remember to increase the shutter speed while increasing the aperture number, in order to keep the same exposure. The distance camera – target should be so that the width of the area photographed is about 30 cm (as in my photos). Well, let me know if something is not clear! thanks!
Antonino, voy a replicar la experiencia en mi laboratorio y te cuento los resultados
saludos!!
Hasta luego!
Hi Antonino,
Here is another database of lenses suitable for UV-VIS-IR imaging:
http://www.macrolenses.de/objektive_sl.php?lang
This database doesn’t have test results for all lenses, but some useful details are available.
Cheers,
Taylor
Hi Taylor, very interesting resource, thanks 🙂