Backfocus — Focus behind the desired plane of focus. (Some photographers might call this a “near sighted” lens). For converted infrared cameras, the amount of backfocus will depend on both the thickness of the replacement glass over the sensor, as well as the optical properties of the lens itself. Removal of the sensor glass entirely can result in severe frontfocus, problematic on lenses that cannot focus past infinity.
Article continues for subscribers...
Already a subscriber? CLICK HERE TO LOG IN
Since 2006, Diglloyd Advanced Photography is the authoritative review and reference for DSLRs and their lenses: Canon and Nikon primarily, but also Pentax and some medium format. Reviews of key DSLRs are included, but the primary focus is on lens performance. Also included is a wealth of technique and workflow approaches.
DAP includes thousands of pages of exclusive coverage and high resolution Retina-grade examples detailing Canon and Nikon DSLR bodies and their lenses, with in-depth analysis of sharpness and contrast, color, bokeh, vignetting, distortion, MTF, and flare, behavioral and practical usage.