Talk:Flange focal distance

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Diagram source[edit]

Recreating a diagram should be straightforward for someone with SVG skills; there are a few available to recreate if you google for "flange focal distance". A diagram could show an internal view of an SLR camera, with the distance between the lens mount and the film plane highlighted. Perhaps something derived from Slr-cross-section.png. grendel|khan 06:50, 26 July 2006 (UTC)[reply]

After spending quite a while drawing a piture myself, I did a search in Wikicommons and found this one which is much simpler and clearer than what I had come up with. Yay Wiki! Egmason (talk) 08:35, 3 February 2012 (UTC)[reply]

Back Focus Adjustment[edit]

This article might be a good place to point out that some camera bodies (especially CS and C-mount) incorporate a (screw) mechanism for moving the sensor along the optical axis. The movement is typically very small (and usually not calibrated) but allows compensation for any "irregularities" in the lens mounting that would upset the flange focal distance. Usage procedure is 1/ mount the lens, 2/ set focus to infinity, 3/ point the lens at a distant building, then 4/ adjust the "back focus" until you obtain the sharpest possible image of the building. 87.102.83.121 (talk) 18:36, 18 August 2008 (UTC)[reply]

And B4 Mounts - move lens away from the flange. Often needed to ensure zooms are 'par-focal' - ie focus doesn't shift when zooming. Procedure is to zoom to a long focal length and focus the lens, zoom out to wide-angle, adjust back-focus at camera; repeat. --195.137.93.171 (talk) 05:55, 21 October 2014 (UTC)[reply]

Number of lenses, which lenses to include?[edit]

Which lenses should be counted for the "number of primes/zooms produced" columns? In production only or including legacy? Manufacturer only or including 3rd party? Should new issues of the same lens (MkII) be counted separate? I have added Samsung NX (also counting 3 samyang primes, but I think there are more), and Pentax K (counting only Pentax lenses, but everything listed in pentaxforums.com, including legacy lenses). --200.120.12.145 (talk) 02:42, 13 March 2012 (UTC)[reply]

Include all legacy lenses, for as long as they use the same mount (don't count lenses using mount adapters). List only lenses by original manufacturer(s), not third-party lenses (as this would be impossible to maintain). Any update (officially distinguished by the manufacturer as a new lens) should be counted (don't count color variants available at the same time, don't count mere firmware updates or internal-only changes). If there is more than one original manufacturer for a mount (f.e. Minolta, Konica Minolta, Sony), distinguish between them and combine the numbers using a "+" symbol. If a mount supports lenses for more than one format (f.e. 35mm full-frame and APS-C format), distinguish between them and combine the numbers with "+". If possible, link the numbers to WP articles or lists discussing these lenses. If possible, leave a  indicating when a number was last updated in order to make it easier to keep the numbers up to date without recounting from scratch. --Matthiaspaul (talk) 23:25, 26 March 2014 (UTC)[reply]

What's the use of such a list anyhow? Taking only the Nikon system there must be hundreds of original Nikon lenses and hundreds of third party lenses. What do I gain if I know that there are 352 (just guessing..) prime lenses for the Nikon F? It's a useless number. Just my opinion.178.165.129.253 (talk) 12:06, 7 December 2017 (UTC)[reply]

Wanted: Flange-focal distance of Samsung Kenox GX-1/Samsung SR4000 mount[edit]

Prior to their cooperation with Pentax, Samsung developed and marketed their own SLR system for a short period of time (1998(1997?)-2002). The camera was named "Samsung Kenox GX-1" in Korea and "Samsung SR4000" in the USA. The mount looked a lot like Minolta's A-mount, but with the aperture lever moved to a slightly different position. It featured 5 lens contacts, but was manual focus only (no AF coupler). It is unknown, however, if this mount was mechanically or electrically compatible with Minolta's A-mount at all (probably not). Despite the name similarities, this mount also had nothing to do with the Pentax K-AF mount as used in the later Samsung GX-family of DSLRs. Does someone know the flange focal distance of this mount? --Matthiaspaul (talk) 22:34, 19 May 2015 (UTC)[reply]

Back focus vs flange distance confusion[edit]

There appears to be much confusion between those two, because they are correlated in practice, but a lens with short flange may have long backfocus or vice-versa (e.g. "invasive" wideangle lenses for early SLR cameras requiring mirror lockup). Alliumnsk (talk) 05:00, 30 March 2017 (UTC) I think you are right, and back focus is also an ambiguous term (has different meaning on broadcast lenses). But the term back focus is not present in this article.Robijn (talk) 13:45, 7 December 2017 (UTC)[reply]

Flange Distance for Panasonic Varimount[edit]

https://www.lensadaptor.com/camera-mount/panasonic-varicam-mount

Type[edit]

I'm wondering which technical type "cine" or " TV" are, which are used inside the table. In my opinion these are usage kinds, but no technical category like SLR/mirorless. --Angerdan (talk) 15:28, 13 March 2021 (UTC)[reply]

Panavision, ARRI, CineAlta, and Red are professional systems for digital cinematography. They're not really comparable to a consumer-level mirrorless system which does both video and stills. There may be some overlap (I guess?), but would it make sense to classify a Red camera as "mirrorless"? - Kzirkel (talk) 17:20, 13 March 2021 (UTC)[reply]

If SLR and mirrorless are "technical categories," I cannot see how cine and video are not. Those are their design functions, and they are distinct and not interchangeable; you cannot, for example, use a C-mount video lens on an SLR, nor will an ENG video lens function properly on a MILC.

In addition, cine and video lenses are constructed differently, featuring things like clickless aperture rings, geared aperture and focus rings, lever-actuated zooms on older lenses, and in the case of video lenses, often built-in handgrips with zoom and record controls, focus and zoom motors, or interfaces to electronic follow-focus/aperture control units. Okto8 (talk) 15:05, 3 May 2024 (UTC)[reply]