|WikiProject Film||(Rated Start-class)|
|WikiProject Photography||(Rated Start-class)|
What is up with this "throat" column in the table? Whoever edited this has fouled up the thread specifications, such as the M42x0.75 T-mount thread, which is now garbage.
Unsigned by: Rkinch ("Throat" sizes is spurious)
Throat sizes? response
To clear things up some more:
- Added a Legend table at the bottom explaining each column
- Separated "Frame size" (8, 16, 35mm, ...) from "Camera type" (digital, still, movie, CCTV)
- Separated "OEM model line(s)" from "Type Name"
- bayonet/breech/screw, diameters, and thread pitches
were all in one column "jumbled up" across rows (there was not consistency between rows).
Reasoning (for separate diameter column):
- With as many variations as there are - (diameter, thread pitch, type) really needed to each be in their own separate columns.
- "Major" or "Throat" diameter is not "spurious": while "flange focal distance" in relation to "frame size" tells you something about a lens's relative focal properties (telephoto versus wide angle relationship), it told you nothing about how much light a lens mount family can gather or how heavy they might be relative to others (i.e. larger mount diameters gather more light and are generally heavier).
The "shorthand notation" M42x0.75 (or M42x1) really means:
- ISO 68-1 metric thread size (see below),
- Nominal major diameter D=42mm x pitch P=0.75mm per thread (or 1mm per thread);
so the (D) 42mm and the (P) 0.75mm are appropriately placed in separate columns
Compared to "mm", an "M" provides some additional information:
- it means that the thread is cut to ISO 68-1 specifications with:
- 60 degree angle (which defines a height H), and
- outermost 1/8 and innermost 1/4 rounding (of height H).
I re-added citations/references for 4/3. FYI - 4/3 is intentionally designed to try to be 1/2 lighter and 1/2 smaller (than corresponding "35mm" Nikon F and D-series and other contemporaries), so it is factual that 4/3 major diameters (D) are NOT ~50mm (which would be as big and heavy as Canon EF and EF-S systems). 4/3 (D) is ~43-44mm and micro-4/3 is ~37-38mm (See Notes section in the article). Digital Photography Review has it "wrong" - DPR is citing the lens/mount female "outside diameter" instead of the major (D) which is the camera body female mount inside diameter or the male lens mount outside diameter. LeheckaG (talk) 17:46, 11 August 2008 (UTC)
"Creating screw threads of the necessary precision, across many camera and lens manufacturers, is too troublesome."
This is just some conjecture on my part. Can anyone offer information supporting or challenging my suggestion? Imroy 20:25, 2005 May 29 (UTC)
A registration distances
M42×1 screw mount registration distance is 45.5 mm (±0.02--0.03 mm), but not 45.46 mm. (See GOST 10332-72 and this document, for example: http://www.zenitcamera.com/archive/lenses/flektogon-2-8-35-adb-lk.tif ) K-mount registration distance is 45.5 mm (±0.02mm) too, not 45.46 mm (±0.03--0.04 mm). KengRu (talk) 14:00, 20 June 2008 (UTC)
This was suggested at Wikipedia:Articles for deletion/Focusing lens mount, I'm posting the mergeto and mergefrom tags to encourage discussion. Stifle 23:18, 6 April 2006 (UTC)
It should be noted that the use of different lens mounts on photo cameras was not primarily due to marketing considerations but due to a patent dispute. There was a broad consensus among camera manufacturers to us a standard mount to replace M42 as it was not adequate for electronic controlled cameras in the late 70's. This consensus was destroyed when one of the manufacturers obtained a patent for the suggested mount and wanted royalties from all others. Alf photoman 14:33, 5 December 2006 (UTC)
- Any idea who that was, or any books or articles talking about it? I know for pretty sure that that's what happened in rangefinder cameras; Leica screw mount was obsolete, Leica invented the M bayonet mount and patented it. It didn't hurt, of course, that marketing considerations also encouraged makers to use incompatible mounts. Matthew Brown (Morven) (T:C) 16:16, 5 December 2006 (UTC)
I recommend that the table in list of lens mounts be moved into this article. Neither is big, and there's no reason for two articles on the same subject with one being just the table. Dicklyon 23:34, 19 September 2007 (UTC)
Hearing no immediate outcry, I went ahead. If anyone objects, say so here or back it out. Dicklyon 20:33, 20 September 2007 (UTC)
- Looks good, but shouldn't it replace the other list in the earlier section? It seems rather redundant now. --Imroy 22:20, 20 September 2007 (UTC)
- The other organization may have some use. Probably it would be best to separate out the list into categories like those. But I don't know the history of who thought what would be more useful, so I decided to do no more yet. Feel free. Dicklyon 07:04, 21 September 2007 (UTC)
Better add to this article some information on common new mounts. Four Thirds mount (Olympus E series, Leica Digilux 3 SLR, Panasonic Lumix SLR) Sony and Zeiss share one too. —Preceding unsigned comment added by 126.96.36.199 (talk) 15:48, 4 July 2008 (UTC)