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How create a 30000 pixel panorama

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  • How create a 30000 pixel panorama

    I am hoping someone here will be able to steer me into the right direction. Presently I provide HDR panorama light domes for the CGI community. My process has been very simple. I use a 8mm lens on a Canon Mark III using a Nodal Ninja mount. But I am now being asked to create 30000 pixel wide HDR panorama domes. I recently used a Nikon 810 using a 24mm lens (if I remember correctly) for a project, which gave me what I was looking for, but it took a lot of images and was difficult to stitch using PT Gui Pro. I am now considering using the Canon 5DS R but not sure what lens would be the best choice to use to get the least of amount of captures and still produce a proper stitched dome. Any info would be appreciated.

  • #2
    I cannot see how you can get away without a lot of images with a full frame DSLR such as your Canon Mark III or the Nikon D810.
    Even with a Nikon D800 and 18mm lens (not fisheye) I took 24 shots to get a width of 23,500 pixels, and that was without filling the nadir, but closing the zenith nicely.
    I would be interested in how you define your "dome", is this a full spherical panorama or just from the equator up for use with something like Igloo Vision?
    The number of images will of course be affected by how much overlap you like.
    I like to have a lot of overlap for Control Point generation so PTGui stitches without having to work at it and to be able to effectively use PTGuis "Mask" tool if there is movement between shots, but you could reduce the number of images by having less overlap.
    From my quick calculations I would think that you would need the 24mm focal length with your Canon Mark III.
    Perhaps someone could comment on the result from a Canon 5DS R with it 50Mp sensor.

    Just made a little experiment:
    D800 image size = 4912 x 7360 which an gives Equirectangular = 22530 x 11265 using the 18mm (not fisheye) lens.
    so I resized the images to 5792 x 8688 to simulate the Canon 5DS R 50Mp sensor and ran these through PTGui and this gives an Equirectangular = 27750 x 13875 so even with the Canon 5DS R you would still need something longer than 18mm, but probably shorter than 24mm, but still a lot of images.
    Last edited by Hugh; 04-03-2018, 03:50 AM.

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    • #3
      Thanks Hugh, this is all very useful information. Also I define the term dome to mean a full spherical.

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      • #4
        I too need to up the resolution of my 360 spherical panos. Up till now I've been using a D7200 (24mp) with a Sigma 4.5mm circular fisheye, shooting at 5 degrees up at four stations (0/90/180/270). They look good to me but are roughly 6300 x 4000. Now I'm told 13,000 pixels wide minimum. I'm guessing even if I shot with my D810 and an 8mm Sigma circular fisheye that resolution would be still only be about 8000 wide.

        Caveat: I'm shooting on a DIY pano head where I can only shoot straight forward (or tilt the ballhead it's attached to up 5 degrees) and only in landscape mode. Given my D7200/4.5mm circular fisheye and DIY pano head is there any way I can shoot to produce a 360 at 13,000 wide? Or is the only way going with a real pano head shooting multiple rows NOT with a circular fisheye?

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        • #5
          Thanks for the information Tinhat, I guess that you are probably best staying with your Canon Mark III and a 24mm fisheye as investing in a Canon 5DS R and a slightly shorter lens is not going to significantly reduce the number of images need for your panoramas.

          Giganweb, with a D810 and Sigma 8mm fisheye your Equirectangulars should be 12,000 x 6,000 or slightly larger.
          Not quite 13,000 x 6,500, but close.
          I used to shoot with a Nikon APS-C sensor and Sigma 4.5mm and the Equirectangulars were about 5,000 x 2,500, so you weer doing well to get 6,300 x 3,150?
          If you shoot with a D810 and 8mm fisheye tilted up by 5 degrees you should be able to shoot four shots round and still close the zenith OK, but I tilt up by 7.5 degrees as this still results in the hole at the nadir being smaller than the head.
          If you decide to shoot multirow panoramas with a non-fisheye lens to get higher resolution panoramas then I would suggest investing in an NN3 (or NN6 if you plan to got motorised in the future) - http://shop.nodalninja.com/.

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          • #6
            Hugh, thanks for your reply. Yeah, I have a Nodal Ninja M2 and a 20mm prime on my to-buy list to start shooting multiple rows. It just seems crazy to me how my four station circular fisheye panos have been fine for my client for a year but now they need 13000. All they can say is that they need to keep up with the competition.

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            • #7
              Hello Giganewb,

              I have been giving this matter some thought and two questions spring to mind:
              Why do they actually need 13000 x 6500 and is 12200 x 6100 really not good enough?
              and
              How are they going to use the Equirectangulars you supply?

              If they do really need 13000 x 6500 then I feel that there are three solutions:
              1) Multi row panoramas with your 20mm prime lens;
              2) Resize the Equirectangulars from four shots round with an FX body (D810) and 8mm to 13000 x 6500;
              3) Output the Equirectangulars from PTGui at 13000 x 6500.

              When outputting from PTGui I usually click the "Set optimum size" box and shooting four shots round with my D800 and Samyang 8mm at +7.5°.
              The "optimum size" for last 14 Equirectangulars I have made vary from 12172 x 6086 to 12252 x 6126.
              I have wondered how PTGui calculates the "optimum size" and did ask the question on the PTGui Forum some years ago but did not receive a definitive answer.

              I decided to make some experiments using my last project - http://360hugh.co.uk/panormas/stourh...ead-in-winter/
              For this I made four Equirectangulars, none of which used the same number of images.
              For this project I used HDR (five shots at one stop intervals), but HDR is no good if there are moving objects such as people or ducks, so for some of the four shots round I would have the HDR image plus the middle image from the HDR so I could use the Mask option in PTGui to have solid figures rather than ghosts so the four Equirectangulars were made up as follows:
              1) 9 images, one of which was a handheld nadir shot, which gave an Equirectangular of 12216 x 6108
              2) 6 images, one of which was a handheld nadir shot, which gave an Equirectangular of 12244 x 6122
              3) 7 images, one of which was a handheld nadir shot, which gave an Equirectangular of 12020 x 6010
              4) 5 images with no nadir shot which gave an Equirectangular of 12260 x 6130
              so clearly the calculation for the optimum size is not straight forward so I feel that outputting at 13000 x 6500 should not be a problem.

              To see if there really was a difference I created three tours, one at the optimum sizes for the Equirectangulars, one with the Equirectangulars output from PTGui at 13000 x 6500 and one with the images output from PTGui at the optimum sizes then resized to 13000 x 6500, and I really could not see any difference, so If I was asked to provide 13000 x 6500 Equirectangulars I would carry on using my D800 and Samyang 8mm with four shots round and output them from PtGui at 13000 x 6500.

              As a matter of interest the sizes of the tours using these three set of images are as follows:
              Output from PTGui at "optimum size" - 93,797 Kb
              Output from PTGui at 13000 x 6500 - 107,338 Kb
              Resized to 13000 x 6500 from "optimum size" - 110,441 Kb

              With respect to the second question, I create my tours in Pano2VR and output a *.ggpkg file which I publish using WordPress which has a 64,000 Kb limit so I have to resize the Equirectangulars down quite a lot to get the tours within this limit.
              For the Stourhead in Winter tour, which has 4 panoramas, I had to get the Equirectangulars down to 9700 x 4850 and for the Stourhead tour, which has 9 panoramas, I had to get the Equirectangulars down to 6000 x 3000!

              I hope this is some help to you, Hugh.
              Last edited by Hugh; 04-15-2018, 10:48 AM.

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              • #8
                Hugh, we all appreciate you taking the time to reply. At the risk of sounding like a complete newb at this (I've been shooting panos for years but never gave a thought to the output size):

                -you keep using the word "Equirectangular". Could you please define that? I'm shooting with a circular fisheye and I'm guessing your Samyang is a rectangular fisheye. The way I shoot I don't need to shoot a zenith to get full coverage of the skies. With your rectangular fisheye I'd guess you'd have to shoot a zenith or just accept partial coverage of the sky

                -I have no idea where my guy got 13,000 wide. It just seems to be some maybe-new industry standard width that everyone now is offering and he has to keep pace. I've tried to up the apparent resolution by dialing up the output image (back when he was insisting on 8000 wide) but he said all that did was interpolate the results, degrading the final panorama.

                -it makes me wonder if circular fisheyes were ever designed with wide panoramas in mind. Or just trick funny single images is all they had in mind. I would guess my only hope is to get the 20mm and a pano head so I can shoot multiple rows then 13,000 will be a piece of cake. Or even the 30,000 wide that the OP is talking about. From easy peasy, four shots, BLAM! done to complicated shooting workflow and complicated time spent in PTGui. Oh well, time marches on.

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                • #9
                  Hello Giganewb,

                  Equirectangular is just the technical term for and image where the width is exactly twice as wide as the height, which is what software such as PTGui or Autopano create from our fisheye originals.

                  I agree, the output size has not really bothered me provided the panoramas look good on the Internet, but I was intrigued by the fact that it did not seem to be a straight forward calculation such as number of images and resolution of the originals, but the resolution of the originals and the number of images clearly does have a big impact.

                  Outputting from PTGui at 13,000 wide when the optimum suggested is say 12,250 is not going to make much difference and I truthfully could not see any difference in my tests.
                  Yes, resizing an image from say 12,250 x 6,125 to 13,000 x 6,500 in Photoshop or whatever is interpolation, but outputting at 13,000 wide instead of a suggested 12,250?
                  We take fisheye images, blend them apply all kinds of mathematical distortions to produce the Equirectangular and then grossly distort them again to create our 360° panoramas.
                  Look at this way; compare a globe with a flat map of the world which shows Greenland much much bigger than India where in fact India is some 3.3 million kmē while Greenland is just two thirds of the size at 2.2 million kmē.
                  The map is the equivalent of our Equirectangular and the globe of our 360° panorama.
                  The distortion long the top and bottom of the Equirectangular is huge when compared with the central axis so is outputting from PTGui at 13,000 wide instead of a suggested 12,250 really an issue?

                  My Samyang 8mm is a fisheye (image attached) which I use with a D800 (FX body) tilted up at +7.5° and I shoot 4 shots round, sometimes with an extra hand held shot to the nadir, and I would be happy outputting from PTGui at 13,000 x 6,500 if that is what was required.
                  I do not take a zenith image as this arrangement fills the zenith nicely.

                  Hm, 13,000 wide seems to be a number plucked from the air, unless anyone else knows otherwise.
                  13,000 wide gives an 84.5 Mp wide Equirectangular, which is quite a bit larger that the very expensive professional cameras such as NCTech's iSTAR of up to 50 Mp and the Ladybug at 30 Mp.

                  Unfortunately, the angle of view of the lens influences the number of shots round and the size of the resulting Equirectangular, so a fisheye with its 180° coverage will allow for less shots, but result in smaller Equirectangulars.

                  I have experimented with various lenses and the results can sometimes be surprising and some of the results are as follow:
                  Using the D800 I get the following results:
                  Nikon 10.5mm fisheye - 4 shots round - 11,000 wide
                  Samyang 8mm fisheye - 4 shots round - 12, 200 wide
                  Sigma 12-24mm Zoom @ 12mm - 26 shots - 3 layers of 8 shots round + 2 zenith shots - 16,400 wide
                  Tamron Zoom @ 16mm - 26 shots - 3 layers of 8 shots round + 2 zenith shots - 20,400 wide
                  so there is clearly a limit to what can be achieved with a fisheye lens.

                  Added 20th April
                  Quote from the PTGui Forum:
                  https://groups.google.com/forum/#!to...ui/c-4JQ_vx4pE
                  "It depends on the optimized lens parameters. These can differ significantly, especially in PTGui 10 which uses the same equidistant fisheye projection for all fisheye lenses. There is no true optimum size because the images are warped in a non uniform way."
                  So I now firmly believe that outputting from PTGui at 13,000 wide instead of a suggested 12,250 is not an issue.
                  Last edited by Hugh; 04-20-2018, 01:46 AM.

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                  • #10
                    Have now installed PTGui 11 and the output Equirectangular size is shown as 13,600 x 6,800 for my D800 + Samyang 8mm fisheye.

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                    • #11
                      Originally posted by Hugh View Post
                      Have now installed PTGui 11 and the output Equirectangular size is shown as 13,600 x 6,800 for my D800 + Samyang 8mm fisheye.
                      OK, shot with your rectangular fisheye? Is there a black spot up there in the sky or did you shoot a zenith? In fact, please detail exactly how you shot this. As it is, I guess we've all concluded an output that wide is impossible with a circular fisheye like I have, even shooting with my D800. Again, you're specifying "Equirectangular". As opposed to some other kind of pano? I wouldn't say that, just that the output size (at least for me using a 24mp camera) is around 6300 wide. Is describing it as "Equirectangular" telling me something specific about how you shot it or the gear you're using?

                      A typical four shot pano with my circular fisheye yields 6252 x 3126 (using a 24mp camera--I'm guessing using a 36mp camera, which I don't have the lens for, would come out around 8000 wide using a circular fisheye). I let PTGui "Set Optimal Size". "Link width and height" is checked. Is your 13,600 wide what PTGui just naturally wanted to output?
                      Last edited by giganewb; 04-21-2018, 03:43 PM.

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                      • #12
                        Kit = Nikon D800 + Samayang 8mm Fisheye Lens + Nodal Ninja R1
                        Four shots round with the R1 set at +7.5°
                        Stitched in PTGui 11 (beta) gives 13,276 x 6,638 at 100% of Optimum Size
                        Stitched in PTGui 10 gives 12,176 x 6088 when "Set optimum size" is clicked so can safely be output at 13,000 X 6,500

                        All the panoramas following were taken with this arrangement - some with an extra shot to fill in the nadir and some without where I have just used a "tripod cap":
                        http://360hugh.co.uk/panormas/the-gr...eam-fair-2017/
                        http://360hugh.co.uk/panormas/stourhead-wiltshire/

                        The lens is shown above in my previous post - note that both lens hood parts need to be taken off to expose the full fisheye

                        Note that in PTGui (both 10 and 11) after "Load images..." the "Crop" needs to be set before "Align images..." is clicked as shown in the image "Cropping Image" - PTGui always puts the Crop as shown in the image on the left for the Samyang 8mm fisheye so it needs to be dragged out to the edge of the circle.

                        The image "Image as part of the final Output" shows how PTGui "stretches" the fisheye image for inclusion in the final output Image.
                        Note that there is plenty of sky and that by tilting the rig up at +7.5° there is plenty of overlap to "close the zenith" without any need for taking a shot straight up.

                        I would suggest that if you are looking to get a fisheye for your D800 that you go for a Samyang 8mm rather than a Sigma 8mm.
                        The Samyang is a lot less than half the price of the Sigma, but this is not down to less quality, but to different construction.
                        Also the Samyang will give a larger output image from PTGui because of this different construction - The Sigma 8mm gives something like 9,000 wide on an FX body (D800) but I no longer have one to check.
                        https://wiki.panotools.org/DSLR_spherical_resolution
                        The Samyang is marketed under a number of different names - see also:
                        https://www.lenstip.com/160.1-Lens_r...roduction.html
                        http://michel.thoby.free.fr/SAMYANG/...%20report.html

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