EXCERPT page containing first few paragraphs. 2024-05-09 22:58:53
UA_SEARCH_BOT_compatible_botmozilla/5.0 applewebkit/537.36 (khtml, like gecko; compatible; claudebot/1.0; +claudebot@anthropic.com) @ 3.145.2.184
For full access, subscribe here. Or click title to login. 
Focusing for Infrared
As will be clear from the lens assessment pages that follow, a camera focus adjustment only makes a few lenses less bad in focus accuracy; there is simply too much variation between lenses in how infrared light is focused (with respect to visible light). In short, do not expect critical focus at f/1.2, f/1.4 or even f/2 and f/2.8. And even if the lens is stopped down to f/8 or f/11, thus increasing depth of field, sharpness will frequently disappoint if the optimal focus is not achieved.
The Canon 5D auto focusing mechanism responds quite well to the use of a B+W 091 (deep red) or 092 (short-wave infrared) filter, almost always producing results that are superior to unfiltered focusing. Therefore, unlike the Nikon D70 lens assessments, the 5D examples on this page are aimed at assessing how well use of filtration improves the focusing accuracy over an unfiltered lens.
Article continues for subscribers...
Diglloyd Monochrome is by yearly subscription. Subscribe now for about 8 cents a day.
BEST DEAL: get full access to ALL 8 PUBLICATIONS for only 68 cents a day ($249.95)!
Diglloyd Infrared Photography covers cameras and lenses for infrared photography.
The coverage explains all the issues involved in shooting for monochrome and in infrared. It is not a review of any particular camera or lens, though many examples are included.
- Monochrome vs color cameras.
- Post processing for monochrome.
- Guidance on workflow for infrared, including black and white and channel swapping for false-color images.
- How infrared renders, and why certain spectral cutoffs matter: false color vs black and white.
- Image quality issues to be on the lookout for in infrared.
- Numerous lens evaluations in infrared.
View an overview of infrared as well as filter spectral transmission plus examples from an optimal lens.