Talk:35 mm equivalent magnification

Notability of the concept, and what to call it
My notability tag was removed, and more marginal sources added, to support this concept, which is not even a WP:NEO, since nobody calls it that, but is a recent concept sometimes invoked.

The source that I removed saying it derived from wikipedia uses the phrasing "Reproduction ratio in the camera in 35mm equivalents is" (what it has from WP is only "According to Wikipedia, (2011), digital macro photography means a total magnification of at least life size on a 150x100mm print", which makes it suspect, but perhaps doesn't rule it out as a source of other bits; but it's a self-published page, so probably not really at the threshold of WP:RS.

The sources added starting at this diff are to uses, but no explicit discussion. 1 says "Maximum magnification	1.0x (2.0x 35mm equivalent)"; 2 says "With its 0.52x magnification, the 50mm is equivalent to 1:1 in the 35mm format; the 35mm is equivalent to 2:1, or two times life-size." 3 (later 4) is a forum discussion arguing about the concept, where a guy says " I personally call it '35mm equivalent magnification'. A '1:1 35mm equivalent' would be 36x24 regardless of the camera used to shoot it." (so I guess that's where our title derives from). New 3 says "Pair it with the EX-25 extension tube, and you get the 35mm-equivalent magnification of 2x".

The term "35mm Equivalent Magnification" is used in the latest ref 4 (PhotographyBLOG).

I don't deny that it's a somewhat useful concept, but there doesn't seem to be anything written on it that we can base an article on, if you discount the forum argument, which is the only place it has been discussed as a concept. It's not at all clear that it will catch on as a spec (as opposed to, say, the "magnification to 150x100 print", which drops the 35mm format that is becoming increasingly irrelevant to modern digital photographers).

And if we decide we need an article on it, we should try to make a title that at least sort of respects the WP:MOS.

I'll put that tag back and give others a chance to look for sources. Dicklyon (talk) 15:58, 11 June 2012 (UTC)


 * The source that you removed only references wikipedia as part of its introduction to macro photography in general, not to "35mm equivalent reproduction ratio", and is not the part of the article I was citing. The concept of 35mm equivalent reproduction ratio and simple equations to determine it are discussed at length in the text that follows, which is part of the methods section on Digital Stereo Macro Photography.


 * Olympus uses the terminology "Maximum image magnification = 1.0x (2.0x : 35mm equivalent)" in its specs (ref. 7);
 * Digital Photography Review used "Macro focusing: 1:1 maximum magnification (2:1 35mm equivalent)" in its review article on the Panasonic (ref. 1);
 * Outdoor Photographer says: "With its 0.52x magnification, the 50mm is equivalent to 1:1 in the 35mm format";
 * DPMag says: "Pair it with the EX-25 extension tube, and you get the 35mm-equivalent magnification of 2x";
 * and PhotographyBLOG uses the term "35mm Equivalent Magnification"


 * ...so perhaps the title should be "35mm Equivalent Magnification" instead of "35mm equivalent reproduction ratio" though I used the terms interchangeably throughout the article. It's common knowledge among photographers that the term "reproduction ratio" is synonymous with "magnification ratio", "magnification factor", or "magnification"; macro photographers use the terms interchangeably:


 * http://www.nikonians.org/html/resources/nikon_articles/other/close-up_macro/macro_1.html


 * "The term magnification or reproduction ratio, such as 1:1 magnification or 1:10 magnification, will crop up with an alarmingly high occurrence within this article." and many many others.


 * Yes I agree that this topic has not been covered in great detail, however what is not debatable is that both Olympus and Panasonic are already using the term as a spec for their Micro 4/3 Macro lenses, albeit as "35mm equivalent magnification" or similar.


 * The reason I chose "35mm equivalent reproduction ratio" rather than "35mm Equivalent Magnification" is that it seems more precise. I will create a new article titled "35mm Equivalent Magnification" and redirect "35mm equivalent reproduction ratio" to that. Thank you. — Preceding unsigned comment added by DSiegfried (talk • contribs)


 * I reverted the improper move. You need to use the "move" link to retitle an article, to preserve the talk page and history.  A sensible title might be "35 mm equivalent magnification", with the space and without the caps.  But I think we'll still need some more opinions on the notability, which we can get via an RfC or an AfD.  Dicklyon (talk) 06:41, 12 June 2012 (UTC)


 * I agree with the idea in your quote "The term magnification or reproduction ratio, such as 1:1 magnification or 1:10 magnification, will crop up with an alarmingly high occurrence within this article", but that says nothing about the "35 mm equivalent" for such a term. I've been known to use "35 mm equivalent ISO speed" and "35 mm equivalent f-number", too, but that doesn't mean I can write WP articles on them.  And I certainly can't cite forum discussions to support them, and mentions in a few datasheets are pretty marginal, too.  See WP:GNG.   Dicklyon (talk) 06:46, 12 June 2012 (UTC)


 * And I think your characterization of the nzphoto ref ("The concept of 35mm equivalent reproduction ratio and simple equations to determine it are discussed at length in the text that follows") is a bit off. Yes, he discusses reproduction ratios a lot, but barely mentions the 35 mm equivalent and gives his equation for it.  This is hardly what I'd call an WP:RS, since it's self-published and had no editorial oversight.  And it's not providing significant coverage of the topic, just mentioning it.  Notability remains in the distance, methinks.  Dicklyon (talk) 06:57, 12 June 2012 (UTC)

"I agree with the idea in your quote "The term magnification or reproduction ratio, such as 1:1 magnification or 1:10 magnification, will crop up with an alarmingly high occurrence within this article", but that says nothing about the "35 mm equivalent" for such a term." I never said it did. That quote was merely to demonstrate that "reproduction ratio" and "magnification" are synonymous. I wasn't using the nikonians.org as a reference in the article

"I've been known to use "35 mm equivalent ISO speed" and "35 mm equivalent f-number", too, but that doesn't mean I can write WP articles on them." There are no manufacturers using those terms, while Olympus and Panasonic and perhaps other lens manufacturers are using the term "35mm equivalent magnification" consistently now in defining macro lens magnification for small format cameras. Whether it's a good idea or not is arguable, but they are using it.

"mentions in a few datasheets are pretty marginal" It's more than just few datasheets. The term is showing up increasingly on many more lens descriptions that I haven't cited. How many are required to make it a "notable" term? Here are some more: http://www.pixalo.com/reviews/showproduct.php/product/425 "It offers a magnification of 1:2 (half life size), which has an image magnification size equivalent to life size (1:1) in a 35mm film photo."

http://vantung.smugmug.com/By-Categories/By-Classifications/Macro/17849441_8s4nhs#!i=1364987165&k=wBMcG9H "Macro Photography has many definitions. To me, it has nothing to do with distance but magnification. If one can magnify a subject to very large size then it doesn't matter how close the photographer is to the subject. It is very difficult to decipher such information from a photo. I use a minimum 35mm equivalent magnification of 1:2 (i.e. half life size on FF camera) to qualify a picture as being "macro", as compared to just "close up".

http://www.harpersphoto.co.uk/product/olympus_35mm_f3_5_macro_zuiko/ "It is extremely compact and the world's lightest macro lens. It offers a magnification of 1:1 life size which has an image magnification size equivalent to 2:1 in a 35mm film camera"

http://www.olympus.co.uk/consumer/dslr_ZUIKO_DIGITAL_ED_50mm_1_2_0_Macro_Specifications.htm "Specifications for the ZUIKO DIGITAL ED 50mm 1:2.0 Macro: 35mm Equivalent Magnification 1.04x "

http://www.olympusamerica.com/crm/oneoffpages/crm_e_macro.asp "This lens will focus down to a 1x magnification ratio. The 35mm equivalent is a 2x magnification ratio"

I have compared these to the references in the articles "35 mm equivalent focal length" and "crop factor", both of which are similar concepts, and the sparse references in those articles don't seem any more detailed than these. Either those articles need more/better citing or you're using higher standards than the creators of those articles were given. DSiegfried (talk) 10:50, 12 June 2012 (UTC)


 * In the case of the f.l. / crop factor, they are discussed in multiple books. When magnification gets there, it will be notable.  In the mean time, a brief section in the article on macro photography would be more appropriate than a standalone article.  Dicklyon (talk) 15:04, 12 June 2012 (UTC)

Shouldn't those articles be cited properly then? In the meantime while this discussion is taking place, I would like to move this to "35mm equivalent magnification" since that seems to be the most common usage. DSiegfried (talk) 21:27, 12 June 2012 (UTC)


 * Not without the space in "35 mm" please, to be consistent with MOS:NUM (look for "Unit symbols" there). But it would be better to wait for the AfD discussion to conclude.  In the meantime, there's a redirect from that malformed name, in case anyone links it.  I'm not sure what your question was in "Shouldn't those articles be cited properly then?"  Which articles?  Cited where?  Probably yes, since "properly" is usually good.  Dicklyon (talk) 22:25, 12 June 2012 (UTC)

Since the name is malformed and not the most common usage I think it would be better to move it. DSiegfried (talk) 22:41, 12 June 2012 (UTC)