Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On 29 November 2012 02:32, Greg 'groggy' Lehey groog...@gmail.com wrote: Where do you find that? I've tried this in the Camera and Lens tab with a photo taken vertically with the 9 mm lens. If I select Rectilinear it tells me 71.5° vertically, which presumably ignores the fact that it's mounted vertically, and doesn't say anything about HFOV. That tallies relatively well with my program above. But when I select circular fisheye it comes up with (only) 92.8°. That's some way from my estimate of 108°. Is there some other place you can get similar results? As far as I remember hugin (or panotools) only refer to HFOV throughout, which depends on the orientation of the image data (so lens corrections values will also depend on image data orientation). I always input my images in portrait and fix any rotation by assigning roll values. Nevertheless you can play with the crop and focal length values and the projection and hugin will calculate an an estimate for the hfov, that's how i came up with the cited figures. Diagonal fov on the other hand will be influenced by a,b,c lens parameters. I also get the same results whether I select full frame fisheye or circular fisheye. What's the difference? Basically only the kind of crop that can be applied to the image, circular vs. rectangular. The very same lens can be a full frame fisheye or a circular fisheye depending on the sensor size of your camera. In any case, I can't see any mathematical correspondence between the focal length and the angle of view for fisheyes. Can anybody point me at some background information? There is no single mathematical correspondence. It all depends on the form of the projection function, of which the focal length typically is the derivative at the lens center. The Samyang is special in that regard as it features a (stereographic) fisheye projection that is different than that of most (all ?) other fisheyes. Back to the original question: For me the step from a wide angle rectilinear to a fisheye was very well worth doing. The noticable but bearable quality difference is outweighted by the much easier stitching with the lower number of shots, especially so for 360x180s. That's interesting. I've asked on the German Olympus forum and got a reply from Reinhard Wagner (the author mentioned above) that confirmed my suspicion that the distortion would be less, since a 360x180° panorama is a form of fisheye image anyway, and the image needs to be distorted less. If you're interested, the thread is at http://oly-e.de/forum/e.e-system/135036.htm Having read that thread, I think both views (fisheyes do not need that much distortion or fisheyes need a lot more distortion) aren't exactly right. Typically the final format for a spherical pano is an equirectangular file. And whether your input images are fisheye or rectilinear doesn't matter that much, as there is always going to be a lot of mapping (or distortion if you want) going on, especially near the poles. The main quality loss here is caused by interpolation, but interpolation routines are good enough (if don't choose bilinear or similar) that you will not be able to tell a difference by eye even if you do interpolation back and forth a few times. Another issue is the compression at the extreme edges of the fisheye. But this can easily be dealt with by sufficient overlap and crop. Felix -- You received this message because you are subscribed to the Google Groups Hugin and other free panoramic software group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On 11/29/2012 01:42 PM, Greg 'groggy' Lehey wrote: Did you read the article? It specifies numerous different projections. And the difference between 140° and 180° can't be attributed just to distortion. Indeed: The angle of view of a fisheye lens is usually between 100 and 180 degrees[ 1] http://en.wikipedia.org/wiki/Fisheye_lens#cite_note-bare_url_a-1 while the focal lengths http://en.wikipedia.org/wiki/Focal_length depend on the film format http://en.wikipedia.org/wiki/Film_format they are designed for. That wasn't what I was referring to, but arguably it needs to be improved. The reference is barely authoritative, and Film format sounds positively archaic. To me, film format for digital cameras refers to the proportions of the CCD. My Minolta has an APS-C sized CCD. Other cameras have CCDs with the same proportions and size as a frame of 35mm film. So the phrase doesn't sound archaic to me. I use several lenses designed for my old 35mm film camera (Minolta Maxum 5), and one designed for Minolta's APS-C sized CCD. The lenses for 35mm film all have a ~1.5 focal length multiplier when used on APS-C-sized film or sensor. So my 500mm tele lens has the field of view of a 750mm tele on my Minolta 7D - which is narrower. So the sensor size a lens was designed for impacts the field of view you get from it. Or so I think, this late at night ... I have no fisheye lens around, preferring to stitch lots of full-resolution images together to make a big panorama, vs using a lens to squeeze a wider image into the same limited number of pixels. Some day would like to buy a Sony A-950 (compatible with my lenses) and using a 36mpixel 35mm full-frame sensor. I like details! :-) -- Gnome Nomad gnomeno...@gmail.com wandering the landscape of god http://www.clanjones.org/david/ http://dancing-treefrog.deviantart.com/ http://www.cafepress.com/otherend/ -- You received this message because you are subscribed to the Google Groups Hugin and other free panoramic software group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On Thursday, 29 November 2012 at 23:58:49 -1000, Gnome Nomad wrote: On 11/29/2012 01:42 PM, Greg 'groggy' Lehey wrote: That wasn't what I was referring to, but arguably it needs to be improved. The reference is barely authoritative, and Film format sounds positively archaic. To me, film format for digital cameras refers to the proportions of the CCD. My Minolta has an APS-C sized CCD. Other cameras have CCDs with the same proportions and size as a frame of 35mm film. So the phrase doesn't sound archaic to me. Well, a more modern term might be sensor format. What does it have to do with film? That's what I consider archaic. So the sensor size a lens was designed for impacts the field of view you get from it. Yes, of course. And that's the point I've been making. I've been talking about Four Thirds sensors, which are roughly half the linear size of a full frame sensor. Greg -- Sent from my desktop computer. Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua pgpKdjgICCkTQ.pgp Description: PGP signature
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
Ultra wide-angle 8mm fisheye lens with exaggerated perspective and approximately 180° angle of view, for dramatic effects Ultra-wide 139.3° diagonal field-of-view for 4/3 size image formats Of course if you use the same lens with different sensor size, the result will be different. That's why the Nikkor 10.5 on a small sensor has a 180° diagonal while on a fullframe sensor the HFOV is around 180°. Did you read the article? It specifies numerous different projections. And the difference between 140° and 180° can't be attributed just to distortion. Indeed: The angle of view of a fisheye lens is usually between 100 and 180 degrees[ 1] http://en.wikipedia.org/wiki/Fisheye_lens#cite_note-bare_url_a-1 while the focal lengths http://en.wikipedia.org/wiki/Focal_length depend on the film format http://en.wikipedia.org/wiki/Film_format they are designed for. At least now you should have a better idea whether or not you want that fisheye lens! I have a fullframe fisheye and it's quite practical to only take 6 pictures horizontally (I have a pano head so I also take a zenith, but I always have issues stitching the nadir, as the shot is handheld to avoid seeing the tripod). -- You received this message because you are subscribed to the Google Groups Hugin and other free panoramic software group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On Thursday, 29 November 2012 at 16:02:03 +0800, RizThon wrote: Ultra wide-angle 8mm fisheye lens with exaggerated perspective and approximately 180° angle of view, for dramatic effects Ultra-wide 139.3° diagonal field-of-view for 4/3 size image formats Of course if you use the same lens with different sensor size, the result will be different. That's why the Nikkor 10.5 on a small sensor has a 180° diagonal while on a fullframe sensor the HFOV is around 180°. I seem to be having difficulty making myself clear. My apologies. To spell it out: - The Olympus 8 mm lens, designed for Four Thirds sensors (21.63 mm diagonal), covers an angle of 180° along this diagonal. - The Samyang (I think that's the original manufacturer), also 8 mm, covers an angle of 139.3° along this same diagonal. And as I said, the difference in angle can't be explained by distortion alone. Did you read the article? It specifies numerous different projections. And the difference between 140° and 180° can't be attributed just to distortion. Indeed: The angle of view of a fisheye lens is usually between 100 and 180 degrees[ 1] http://en.wikipedia.org/wiki/Fisheye_lens#cite_note-bare_url_a-1 while the focal lengths http://en.wikipedia.org/wiki/Focal_length depend on the film format http://en.wikipedia.org/wiki/Film_format they are designed for. That wasn't what I was referring to, but arguably it needs to be improved. The reference is barely authoritative, and Film format sounds positively archaic. I was referring to section 3, http://en.wikipedia.org/wiki/Fisheye_lens#Mapping_function which discusses the projections and gives a reason for the big differences in angle. At least now you should have a better idea whether or not you want that fisheye lens! I don't see any input to that decision from this discussion. I have a fullframe fisheye and it's quite practical to only take 6 pictures horizontally (I have a pano head so I also take a zenith, but I always have issues stitching the nadir, as the shot is handheld to avoid seeing the tripod). Indeed. I've taken the coward's way out and done without a nadir, so looking straight down shows a black hole. Greg -- Sent from my desktop computer. Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua pgpwdXOqCZ38f.pgp Description: PGP signature
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
Hi Greg, in my opinion better is relative. If you want more quality and zoom possibility then the most narrow angle the lens has, more close to these objectives you will be. If you want an easy stitch, using less images will make you achieve the final result in less time, then the more open angle the lens has, the better it is. It doesn't matter if the lens is a fish eye or a rectilinear, as hugin treats the distortions to make the job. You just need to configure the lens correctly: if you use a fish eye and doesn't set the lens as one, then you will have problems. Going back to your specific example, I don't think 9mm will have a much narrow angle than an 8mm lens. Do you have their fov to compare? Probably you will use the same number of images to stitch and will have almost the same final image size. Cheers, Carlos E G Carvalho (Cartola) http://cartola.org/360 http://www.panoforum.com.br/ 2012/11/27 Greg 'groggy' Lehey groog...@gmail.com I do a lot of 360x180 panoramas with an Olympus 9-18 mm rectilinear lens (equivalent to 18 mm full frame). I've been offered an 8 mm fisheye. Which is better for this kind of panorama? Greg -- Sent from my desktop computer. Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua -- You received this message because you are subscribed to the Google Groups Hugin and other free panoramic software group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On 28 November 2012 12:10, Carlos Eduardo G. Carvalho (Cartola) cartol...@gmail.com wrote: Going back to your specific example, I don't think 9mm will have a much narrow angle than an 8mm lens. Do you have their fov to compare? Probably you will use the same number of images to stitch and will have almost the same final image size. Having shot myself in the past with a 10mm rectilinear lens (Sigma 10-20mm) and a 10mm fisheye (Tokina 10-17mm) I can tell you that the difference in hfov is very noticeable. It's basically the difference between 2 rows of 8 shots, nadir, zenith (so 18 shots total) and 6 shots around, nadir, zenith (maybe two, I don't remember right now) so 8 oder 9 shots in total. You can actually enter the numbers in hugin to get an estimate. Assuming crop factor 2 9 mm rectilinear yields 90° hfov while 8 mm circular fisheye yields about 130° hfov. Back to the original question: For me the step from a wide angle rectilinear to a fisheye was very well worth doing. The noticable but bearable quality difference is outweighted by the much easier stitching with the lower number of shots, especially so for 360x180s. Cheers, Felix -- You received this message because you are subscribed to the Google Groups Hugin and other free panoramic software group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On Wednesday, 28 November 2012 at 17:18:57 +0100, Felix Hagemann wrote: On 28 November 2012 12:10, Carlos Eduardo G. Carvalho (Cartola) cartol...@gmail.com wrote: Going back to your specific example, I don't think 9mm will have a much narrow angle than an 8mm lens. Do you have their fov to compare? Partially. The 9 mm has: Horizontal FOV: 87.73° Diagonal FOV: 100.49° Vertical FOV:71.68° I don't have a formula for fisheyes, so I can't give the output of my program, but I'm told that it has 180° on the diagonal. Being a fisheye, this *should* mean (on a 4:3 aspect ratio) a horizontal FOV of 144° and a vertical FOV of 108°. That's a long way from the 9 mm. Probably you will use the same number of images to stitch and will have almost the same final image size. Having shot myself in the past with a 10mm rectilinear lens (Sigma 10-20mm) and a 10mm fisheye (Tokina 10-17mm) I can tell you that the difference in hfov is very noticeable. It's basically the difference between 2 rows of 8 shots, nadir, zenith (so 18 shots total) and 6 shots around, nadir, zenith (maybe two, I don't remember right now) so 8 oder 9 shots in total. Yes, this matches my experience and expectations. I currently take 8 shots per row with the camera mounted vertically, and 2½ rows (the top row touching the zenith at 90° intervals), for a total of 20 images. I do it this way because of issues stitching with only a single zenith image. Reading Reinhard Wagner's Profibuch HDR-Fotografie (sorry, only in German), which refers to exactly this fisheye lens, he suggests 60° intervals and one row, which sounds pretty much like what you're doing. You can actually enter the numbers in hugin to get an estimate. Assuming crop factor 2 9 mm rectilinear yields 90° hfov while 8 mm circular fisheye yields about 130° hfov. Where do you find that? I've tried this in the Camera and Lens tab with a photo taken vertically with the 9 mm lens. If I select Rectilinear it tells me 71.5° vertically, which presumably ignores the fact that it's mounted vertically, and doesn't say anything about HFOV. That tallies relatively well with my program above. But when I select circular fisheye it comes up with (only) 92.8°. That's some way from my estimate of 108°. Is there some other place you can get similar results? I also get the same results whether I select full frame fisheye or circular fisheye. What's the difference? In any case, I can't see any mathematical correspondence between the focal length and the angle of view for fisheyes. Can anybody point me at some background information? Back to the original question: For me the step from a wide angle rectilinear to a fisheye was very well worth doing. The noticable but bearable quality difference is outweighted by the much easier stitching with the lower number of shots, especially so for 360x180s. That's interesting. I've asked on the German Olympus forum and got a reply from Reinhard Wagner (the author mentioned above) that confirmed my suspicion that the distortion would be less, since a 360x180° panorama is a form of fisheye image anyway, and the image needs to be distorted less. If you're interested, the thread is at http://oly-e.de/forum/e.e-system/135036.htm Greg -- Sent from my desktop computer. Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua pgpbRtpXOBhn6.pgp Description: PGP signature
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
2012/11/29 Greg 'groggy' Lehey groog...@gmail.com Partially. The 9 mm has: Horizontal FOV: 87.73° Diagonal FOV: 100.49° Vertical FOV:71.68° I don't have a formula for fisheyes, so I can't give the output of my program, but I'm told that it has 180° on the diagonal. Being a fisheye, this *should* mean (on a 4:3 aspect ratio) a horizontal FOV of 144° and a vertical FOV of 108°. That's a long way from the 9 mm. There can indeed be a big difference between a 9mm rectilinear lens and an 8mm fisheye lens, even if 9 doesn't sound that far from 8. It's also possible to have fisheyes from different vendors with different mm, even if they are all fullframe or circular. I also get the same results whether I select full frame fisheye or circular fisheye. What's the difference? I find it weird that it gives the same result... A fullframe fisheye gives you an image corresponding to the biggest rectangle (because your sensor is a rectangle) in a circle, that's why the diagonals are 180°, but horizontal and especially vertical won't be as much. A circular fisheye will give you the biggest circle on your rectangular sensor. So you'll see a circular image with 180° in all directions, but around that circle you'll have black part, because no light ended up on those parts of the sensor. Theoritically, with a circular fisheye, you could only need 2 pictures, while with a fullframe you'd need a few more. -- You received this message because you are subscribed to the Google Groups Hugin and other free panoramic software group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On Thursday, 29 November 2012 at 10:29:19 +0800, RizThon wrote: 2012/11/29 Greg 'groggy' Lehey groog...@gmail.com Partially. The 9 mm has: Horizontal FOV: 87.73° Diagonal FOV: 100.49° Vertical FOV:71.68° I don't have a formula for fisheyes, so I can't give the output of my program, but I'm told that it has 180° on the diagonal. Being a fisheye, this *should* mean (on a 4:3 aspect ratio) a horizontal FOV of 144° and a vertical FOV of 108°. That's a long way from the 9 mm. There can indeed be a big difference between a 9mm rectilinear lens and an 8mm fisheye lens, even if 9 doesn't sound that far from 8. It's also possible to have fisheyes from different vendors with different mm, even if they are all fullframe or circular. Indeed. This is what has been puzzling me. There are two different 8 mm fisheyes available for Olympus: the relatively expensive 8 mm f/3.5 from Olympus, and the 8 mm f/3.5 from various rebadgers (Bower, Samyang, Rokinon). The former costs about $800 and has a full 180° diagonal angle of view. The latter costs about $300, and from the specs state an angle of 139.3° on Four Thirds. From what I've read it will only give a full diagonal 180° on APS-C cameras. http://www.bhphotovideo.com/c/product/880776-REG/Bower_sly358od_8mm_f_3_5_For_Olympus.html Since my last message I've been reading a bit about fisheyes, and it seems that, like Hugin, there are various projections. http://en.wikipedia.org/w/index.php?title=Fisheye_lensaction=editsection=12 gives some information, though I'm still trying to digest it. At least one of the images appears to show a horizontal angle of more than 180°. If anybody knows more details, I'd be interested. I also get the same results whether I select full frame fisheye or circular fisheye. What's the difference? I find it weird that it gives the same result... A fullframe fisheye gives you an image corresponding to the biggest rectangle (because your sensor is a rectangle) in a circle, that's why the diagonals are 180°, but horizontal and especially vertical won't be as much. OK, and that's what the Olympus is. But there's the implicit assumption that *somewhere* there's a 180° angle. That's clearly not the case for some lenses. Greg -- Sent from my desktop computer. Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua pgp7MNoWV0NYu.pgp Description: PGP signature
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
Indeed. This is what has been puzzling me. There are two different 8 mm fisheyes available for Olympus: the relatively expensive 8 mm f/3.5 from Olympus, and the 8 mm f/3.5 from various rebadgers (Bower, Samyang, Rokinon). The former costs about $800 and has a full 180° diagonal angle of view. The latter costs about $300, and from the specs state an angle of 139.3° on Four Thirds. From what I've read it will only give a full diagonal 180° on APS-C cameras. I feel like the full 180° *diagonal* angle of view from Olympus and the 139.5° (as it's not specified it should be horizontal, which is what is normally used) from Bower ends up being almost the same (you computed for a fullframe fisheye 144°) Since my last message I've been reading a bit about fisheyes, and it seems that, like Hugin, there are various projections. http://en.wikipedia.org/w/index.php?title=Fisheye_lensaction=editsection=12 gives some information, though I'm still trying to digest it. Each lens displays what it sees, and there are usually distortions compared to reality. So even with normal non fisheye / non very wide angles, you have distortions. Those distortions are directly linked to the way the lens is built, and thus different lenses with the same FOV will have different distortions (even if they are not really noticeable). At least one of the images appears to show a horizontal angle of more than 180°. If anybody knows more details, I'd be interested. For me a real fisheye lens should have at least a diagonal of 180° for FF, or a full 180° circle for circular (or at least quite close to 180°). It's possible that some vendors use the term fisheye just because of the look of the pictures you can take. Note also that some lenses have an angle of more than 180° (there's the huge Nikkor 6mm with a 220° angle, meaning you starts seeing what's behind you! Or the full frame fisheye Nikkor 10.5mm made for small sensors, but that actually has an angle of a little bit more than 180° when used on a full frame camera). -- You received this message because you are subscribed to the Google Groups Hugin and other free panoramic software group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
Re: [hugin-ptx] Rectilinear or fisheye lens: which is better?
On Thursday, 29 November 2012 at 13:43:46 +0800, RizThon wrote: Indeed. This is what has been puzzling me. There are two different 8 mm fisheyes available for Olympus: the relatively expensive 8 mm f/3.5 from Olympus, and the 8 mm f/3.5 from various rebadgers (Bower, Samyang, Rokinon). The former costs about $800 and has a full 180° diagonal angle of view. The latter costs about $300, and from the specs state an angle of 139.3° on Four Thirds. From what I've read it will only give a full diagonal 180° on APS-C cameras. I feel like the full 180° *diagonal* angle of view from Olympus and the 139.5° (as it's not specified it should be horizontal, It's specified in the descriptions of other rebadged versions of this lens. Go to (for example) http://www.bhphotovideo.com/c/product/769514-REG/Rokinon_FE8M_O_8mm_Ultra_Wide_Angle.html and read: Ultra wide-angle 8mm fisheye lens with exaggerated perspective and approximately 180° angle of view, for dramatic effects Ultra-wide 139.3° diagonal field-of-view for 4/3 size image formats The Bower badged lens is also available for Canon (APS-C). http://www.bhphotovideo.com/c/product/635178-REG/Bower_SLY358C_SLY_835C_8mm_f_3_5.html states: 180° diagonal angle of view on APS-C image format. which is what is normally used) from Bower ends up being almost the same (you computed for a fullframe fisheye 144°) Yes, but diagonal values look better for selling the product :-) Since my last message I've been reading a bit about fisheyes, and it seems that, like Hugin, there are various projections. http://en.wikipedia.org/w/index.php?title=Fisheye_lensaction=editsection=12 gives some information, though I'm still trying to digest it. Each lens displays what it sees, and there are usually distortions compared to reality. So even with normal non fisheye / non very wide angles, you have distortions. Those distortions are directly linked to the way the lens is built, and thus different lenses with the same FOV will have different distortions (even if they are not really noticeable). Did you read the article? It specifies numerous different projections. And the difference between 140° and 180° can't be attributed just to distortion. At least one of the images appears to show a horizontal angle of more than 180°. If anybody knows more details, I'd be interested. For me a real fisheye lens should have at least a diagonal of 180° for FF, or a full 180° circle for circular (or at least quite close to 180°). It's possible that some vendors use the term fisheye just because of the look of the pictures you can take. Clearly it's related to the projection. Greg -- Sent from my desktop computer. Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua pgp6dWjPXRutb.pgp Description: PGP signature
