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#161
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Big Lenses, was Ping Tony Cooper
In article , Ken Hart
wrote: But the biggest lens I've seen in real life was a nikon 6mm fisheye in the mid 70s. I've never seen that lens in real life, but I remember the "excitement" when it was introduced. I googled it, and found https://www.mir.com.my/rb/photograph...rces/fisheyes/ 6mmf28.htm has a pretty nice writeup about it. For those who just want the highlights: a 220 degree angle of view, 236mm (9.29") diameter, 171mm (6.73") long, weight 5.2Kg (11.46 pounds). The website doesn't give a price, but mentions that it was special order. $6k in 1970s dollars. $161k today, due to its rarity, at least this one: https://www.theverge.com/2012/4/24/2...on-6mm-f2-8-le ns-for-sale-london |
#162
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Ping Tony Cooper
On Tue, 2 Oct 2018 01:55:14 -0700 (PDT), Whisky-dave
wrote: On Monday, 1 October 2018 18:59:22 UTC+1, -hh wrote: On Monday, October 1, 2018 at 11:16:33 AM UTC-4, Whisky-dave wrote: On Friday, 28 September 2018 18:08:55 UTC+1, -hh wrote: nospam wrote: -hh wrote: a long lens does not become not long because someone uses it in a different manner. Which must be why nospam not only dodged answering my two examples of context mattering, but he furthermore deleted them from his response, clearly in hopes that readers would not notice his dodge. i didn't dodge anything. Then what’s the answer for each example provided? Don’t dodge again. i answered your question, which covered both of your examples. Except that you dodged making a declarative statement: is my 35mm long or short? cough I'd call that a little prick. Yeah, I deserved that for not *pedantically* including the word "lens" :-) In any event, this was a tricky questions for pendants, as the lens in question is the Nikon's amphibious Nikkor 35mm for the Nikonos, which has an integral flat port. As such, while it acts short out of the water, it becomes a normal when used in its primary intended application of underwater (the field of view in air is 52 degrees, which changes to 38 degrees), as it is equivalent to a 52mm lens. However, in practical application, the Nikkor 35mm was broadly considered to be a bad (undesirable) lens that everyone owned anyway, I didn't I've never owned an nilon or nikkor lens. But the biggest lens I've seen in real life was a nikon 6mm fisheye in the mid 70s. because it usually came bundled with the body, because for the contextual application of underwater photography, it was too "long" for most UW interests. Barring the novice who didn't (yet) own any other lenses, virtually the only place you would ever find it being used was with extension tubes for macro, If you put esxtention tubes on a lens does that make the lens bigger ? I don't know as again it depends on what a person means by size as that is as relative to an individual. .... and the circumstances under discussion. but even this was largely self-fulfilling, since Nikon's macro kit only came with framers for use with the 35mm lens; one had to seek out a 3rd party aftermarket for framers for the more usable 28mm. Plus shooting wide didn't really start becoming "wide enough" until 20mm, with 15mm being the premier lens: historically, the 15mm was the "cash cow" lens with the highest rate of success in selling covers for the rec scuba trade magazines... As I said it's all relative just like incest. And how about my 60mm - long or short? 6cm still a bit on the short side. Now if you were talking inches then that's pretty normal. Yup. As Eric pointed out in his statement, how happy one is with length also depends on the receptor size ...yes, I meant to say "of the _camera_ body"! What else might you have been talking about just any orifice. -hh -- Regards, Eric Stevens |
#163
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Ping Tony Cooper
On Tue, 02 Oct 2018 08:40:34 -0400, nospam
wrote: In article , Eric Stevens wrote: the physical properties of a lens are *not* an opinion. But what is normal and hence what is long is an opinion. no Yes. I have already given you the Wikipedia definition of normal https://en.wikipedia.org/wiki/Normal_lens "... a normal lens is a lens that reproduces a field of view that appears "natural" to a human observer." Under the heading of "What is 'normal" it says "A test of what is a normal lens then, is to find one that renders a printed (or otherwise displayed) photograph of a scene that when held at 'normal' viewing distance (usually arms-length) in front of the original scene and viewed with one eye, matches the real-world and the rendered perspective, though Maurice Pirenne (in 1970) and others demonstrate that it is possible to see a scene made with any lens in normal perspective if one adjusts the viewing distance; but impractically close to the image for wide angle photographs and further away for a telephoto, and views it from a static point at the centre of perspective from which the image was made ... " In other words that while whether or not a lens is normal may be a subjective judgement the work of Maurice Pirenne shows that any lens may be regarded as normal. Lower down the Wikipedia article says "For still photography, a lens with a focal length about equal to the diagonal size of the film or sensor format is considered to be a normal lens; its angle of view is similar to the angle subtended by a large-enough print viewed at a typical viewing distance equal to the print diagonal;[12] this angle of view is about 53° diagonally. For cinematography, where the image is larger relative to viewing distance, a wider lens with a focal length of roughly a quarter of the film or sensor diagonal is considered 'normal'. The term normal lens can also be used as a synonym for rectilinear lens. This is a completely different use of the term." It is clear that even for constant image dimensions the focal length ascribed to a 'normal' lens is very much a moveable feast dependent on the viewer and their circumstances. That is why I wrote "what is long is an opinion". -- Regards, Eric Stevens |
#164
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Ping Tony Cooper
In article , Eric Stevens
wrote: Lower down the Wikipedia article says "For still photography, a lens with a focal length about equal to the diagonal size of the film or sensor format is considered to be a normal lens; which means that anything longer than that is a long lens. very simple. that's also consistent with wikipedia: https://en.wikipedia.org/wiki/Long-focus_lens In photography, a long-focus lens is a camera lens which has a focal length that is longer than the diagonal measure of the film or sensor that receives its image. it's also in agreement with what ken said, which tony confirmed was correct (contradicting his initial claim), up until he realized that meant i was also correct, at which point he quickly changed back to long lens is an opinion idiocy and then lied about it. its angle of view is similar to the angle subtended by a large-enough print viewed at a typical viewing distance equal to the print diagonal;[12] this angle of view is about 53° diagonally. For cinematography, where the image is larger relative to viewing distance, a wider lens with a focal length of roughly a quarter of the film or sensor diagonal is considered 'normal'. The term normal lens can also be used as a synonym for rectilinear lens. This is a completely different use of the term." It is clear that even for constant image dimensions the focal length ascribed to a 'normal' lens is very much a moveable feast dependent on the viewer and their circumstances. That is why I wrote "what is long is an opinion". you're moving the goalposts again. different formats (including your graflex) will have different numbers, and video will obviously be different yet since the image is projected with viewers further back, plus most video is now widescreen. nothing about it is opinion, just different sets of numbers. once again: "For still photography, a lens with a focal length about equal to the diagonal size of the film or sensor format is considered to be a normal lens; for 35mm full frame still cameras, 50-55mm is considered normal, which is actually a little longer than the frame size (~43mm) because 50mm is a simple lens design and therefore cheap to manufacture as well as being long enough to not need a retrofocus design due to the fixed flange distance of the mirror box, which for nikon f is 46.5mm. and then there's tolerances. focal lengths are within 5% of stated, so a 50mm lens is actually anywhere from 47.5mm to 52.5mm. nikon dx, including the d300 mentioned early in the thread, has a 1.5x crop factor, so normal is 35mm (52.5mm effective). tl;dr lenses longer than normal are long lenses. very simple. |
#165
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Ping Tony Cooper
On Wed, 03 Oct 2018 00:07:41 -0400, nospam
wrote: In article , Eric Stevens wrote: Lower down the Wikipedia article says "For still photography, a lens with a focal length about equal to the diagonal size of the film or sensor format is considered to be a normal lens; which means that anything longer than that is a long lens. very simple. that's also consistent with wikipedia: https://en.wikipedia.org/wiki/Long-focus_lens In photography, a long-focus lens is a camera lens which has a focal length that is longer than the diagonal measure of the film or sensor that receives its image. That's what it says in the Wikipedia article you have just cited but the relevance of "the diagonal measure of the film or sensor that receives its image" is that this is (but) one of the ways of defining a normal lens. So that article is saying quite reasonably "In photography, a long-focus lens is a camera lens which has a focal length that is longer than [insert your definition of a normal lens here]". At this point one gets down to splitting hairs about what exactly is a normal lens. it's also in agreement with what ken said, which tony confirmed was correct (contradicting his initial claim), up until he realized that meant i was also correct, at which point he quickly changed back to long lens is an opinion idiocy and then lied about it. its angle of view is similar to the angle subtended by a large-enough print viewed at a typical viewing distance equal to the print diagonal;[12] this angle of view is about 53° diagonally. For cinematography, where the image is larger relative to viewing distance, a wider lens with a focal length of roughly a quarter of the film or sensor diagonal is considered 'normal'. The term normal lens can also be used as a synonym for rectilinear lens. This is a completely different use of the term." It is clear that even for constant image dimensions the focal length ascribed to a 'normal' lens is very much a moveable feast dependent on the viewer and their circumstances. That is why I wrote "what is long is an opinion". you're moving the goalposts again. Not at all. I'm confining myself to the baseline from which loner or shorter lenses are measured. different formats (including your graflex) will have different numbers, and video will obviously be different yet since the image is projected with viewers further back, plus most video is now widescreen. nothing about it is opinion, just different sets of numbers. Opinion comes into deciding which definition of normal should be used for the purpose of discussion. once again: "For still photography, a lens with a focal length about equal to the diagonal size of the film or sensor format is considered to be a normal lens; "about"? "ABOUT?". Now how is that for certainty and precision? for 35mm full frame still cameras, 50-55mm is considered normal, which is actually a little longer than the frame size (~43mm) because 50mm is a simple lens design and therefore cheap to manufacture as well as being long enough to not need a retrofocus design due to the fixed flange distance of the mirror box, which for nikon f is 46.5mm. and then there's tolerances. focal lengths are within 5% of stated, so a 50mm lens is actually anywhere from 47.5mm to 52.5mm. nikon dx, including the d300 mentioned early in the thread, has a 1.5x crop factor, so normal is 35mm (52.5mm effective). tl;dr lenses longer than normal are long lenses. very simple. And you ask why I was discussing the various definitions of normal? -- Regards, Eric Stevens |
#166
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Ping Tony Cooper
On Wed, 3 Oct 2018 02:28:25 -0700 (PDT), Whisky-dave
wrote: On Wednesday, 3 October 2018 01:15:50 UTC+1, Eric Stevens wrote: On Tue, 2 Oct 2018 01:55:14 -0700 (PDT), Whisky-dave wrote: On Monday, 1 October 2018 18:59:22 UTC+1, -hh wrote: On Monday, October 1, 2018 at 11:16:33 AM UTC-4, Whisky-dave wrote: On Friday, 28 September 2018 18:08:55 UTC+1, -hh wrote: nospam wrote: -hh wrote: a long lens does not become not long because someone uses it in a different manner. Which must be why nospam not only dodged answering my two examples of context mattering, but he furthermore deleted them from his response, clearly in hopes that readers would not notice his dodge. i didn't dodge anything. Then what’s the answer for each example provided? Don’t dodge again. i answered your question, which covered both of your examples. Except that you dodged making a declarative statement: is my 35mm long or short? cough I'd call that a little prick. Yeah, I deserved that for not *pedantically* including the word "lens" :-) In any event, this was a tricky questions for pendants, as the lens in question is the Nikon's amphibious Nikkor 35mm for the Nikonos, which has an integral flat port. As such, while it acts short out of the water, it becomes a normal when used in its primary intended application of underwater (the field of view in air is 52 degrees, which changes to 38 degrees), as it is equivalent to a 52mm lens. However, in practical application, the Nikkor 35mm was broadly considered to be a bad (undesirable) lens that everyone owned anyway, I didn't I've never owned an nilon or nikkor lens. But the biggest lens I've seen in real life was a nikon 6mm fisheye in the mid 70s. because it usually came bundled with the body, because for the contextual application of underwater photography, it was too "long" for most UW interests. Barring the novice who didn't (yet) own any other lenses, virtually the only place you would ever find it being used was with extension tubes for macro, If you put esxtention tubes on a lens does that make the lens bigger ? I don't know as again it depends on what a person means by size as that is as relative to an individual. ... and the circumstances under discussion. How or why does a person describe a 'lens' the way they do. If I put an extention tube on a lens does it make the lens longer as a description of a lens. As you've failed to understand this point I'll ask you how you measure a lens, what is a large lens what is a big lens ? Is the nikon 6mm f2.8 a big lens. I'd say so but I wouldn't call it a long lens. How do I measure a lens? For ordinary conversational purposes, I bring to mind a picture of the lens and the type of image I wish to shoot with it and then, if you ask me what it is, I will probably name it by its focal length. -- Regards, Eric Stevens |
#167
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Ping Tony Cooper
On 10/04/2018 05:49 AM, Whisky-dave wrote:
On Thursday, 4 October 2018 02:02:27 UTC+1, Eric Stevens wrote: On Wed, 3 Oct 2018 02:28:25 -0700 (PDT), Whisky-dave wrote: On Wednesday, 3 October 2018 01:15:50 UTC+1, Eric Stevens wrote: On Tue, 2 Oct 2018 01:55:14 -0700 (PDT), Whisky-dave wrote: On Monday, 1 October 2018 18:59:22 UTC+1, -hh wrote: On Monday, October 1, 2018 at 11:16:33 AM UTC-4, Whisky-dave wrote: On Friday, 28 September 2018 18:08:55 UTC+1, -hh wrote: nospam wrote: -hh wrote: a long lens does not become not long because someone uses it in a different manner. Which must be why nospam not only dodged answering my two examples of context mattering, but he furthermore deleted them from his response, clearly in hopes that readers would not notice his dodge. i didn't dodge anything. Then what’s the answer for each example provided? Don’t dodge again. i answered your question, which covered both of your examples. Except that you dodged making a declarative statement: is my 35mm long or short? cough I'd call that a little prick. Yeah, I deserved that for not *pedantically* including the word "lens" :-) In any event, this was a tricky questions for pendants, as the lens in question is the Nikon's amphibious Nikkor 35mm for the Nikonos, which has an integral flat port. As such, while it acts short out of the water, it becomes a normal when used in its primary intended application of underwater (the field of view in air is 52 degrees, which changes to 38 degrees), as it is equivalent to a 52mm lens. However, in practical application, the Nikkor 35mm was broadly considered to be a bad (undesirable) lens that everyone owned anyway, I didn't I've never owned an nilon or nikkor lens. But the biggest lens I've seen in real life was a nikon 6mm fisheye in the mid 70s. because it usually came bundled with the body, because for the contextual application of underwater photography, it was too "long" for most UW interests. Barring the novice who didn't (yet) own any other lenses, virtually the only place you would ever find it being used was with extension tubes for macro, If you put esxtention tubes on a lens does that make the lens bigger ? I don't know as again it depends on what a person means by size as that is as relative to an individual. ... and the circumstances under discussion. How or why does a person describe a 'lens' the way they do. If I put an extention tube on a lens does it make the lens longer as a description of a lens. As you've failed to understand this point I'll ask you how you measure a lens, what is a large lens what is a big lens ? Is the nikon 6mm f2.8 a big lens. I'd say so but I wouldn't call it a long lens. How do I measure a lens? For ordinary conversational purposes, I bring to mind a picture of the lens and the type of image I wish to shoot with it and then, if you ask me what it is, I will probably name it by its focal length. That sounds reasonable as reasonable as me saying I would love a kebab or I could murder a kebab or eat a horse, or I'd love to play with the leica 2000mm but is it longer than say a canon 600mm f4L . Some expect technical accuracy fromm such statements as long, short, wide, big, small and all of this is open to interpretation, so my 75/300 IS longer when I add extention tubes, it's also bigger and heavier but as far as I know the focal lengh remains the same provided I don't zoom or focus. I get a simialr thing in my job with studetns asking for a large resistor or capacitor asking me what the largest or smallest I have in stock, so I ask them do they mean the value or rating or the physical size, that;s when they have to start thinging and I can take a nap ;-) Can I get a 10K-ohm 1/2W carbon composition resistor and a 25uF 25wVDC radial lead electrolytic after you're done with your nap? -- Ken Hart |
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