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I've shot a 5 gigapixel 360 degree panorama, totaling around 1400 shots in a -1.3-0-+1.3 bracket, and I'm trying to stitch it and tone map it. So far I've managed to decently assembled the panorama in Autopano Giga and render it a few times, but I'm unable to tonemap the resulting image. I'd rather not tonemap before stitching as this has the potential to create uneven exposures, particularly across a 360 degree panorama.

Steps I've tried:

  • Exporting a .psb with layers - Photoshop's tone mapping won't deal with this
  • Exporting a .hdr and tonemapping with Photomatix - Photomatix tries to save the .tiff as but this results in a file over the 4gb limit which is corrupt
  • Exporting individual .tiff files and merging with Photomatix - Photomatix crashes immediately after (apparently) finishing the merge to HDR.

Note that I have Photoshop, Autopano Giga and Photomatix Pro available currently, and possibly more from my university. I'm a fan of Photomatix's control and the resulting images but it seems unable to handle such large images.

What software would appropriate for tonemapping an image this large?

  • 1
    "What software would appropriate for tonemapping an image this large?" I'd be willing to lay odds on you being the expert on something like this. Interesting question, absolutely huge imageset to both stitch and tonemap. I'm watching this one with interest. – scottbb Apr 24 '16 at 1:10
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    Trust me, my desktop (i7-4790k, 16GB RAM and multiple TB scratch disk available) is running 24/7 trying to find something which can handle this. Every re-render is on the order of 15 hours - I haven't even found a good way to convert from one 32-bit format to another. The scary part is that this panorama was taken with a 135mm lens and I just received a 500mm mirror lens in the mail... – gjsmo Apr 24 '16 at 3:04
  • I found this: chasejarvis.com/blog/… Not sure if it will help though – KohGeek Apr 24 '16 at 6:11
  • Why not just chop your stitched panorama in small pats and apply the tone mapping separately to each part (such that it is consistent over the whole set of the separate parts) and then put the whole thing together again? Note that people were able to work with large images back in the 1960s when all they had were primitive punch card computers. – Count Iblis Apr 24 '16 at 16:41
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    Have you tried downloading some more RAM? – dav1dsm1th Apr 25 '16 at 0:02
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It turns out I manged to find a way to tonemap this monster of an image. Theoretically this should work for any image size up to 300000x300000 (90GP), which is the maximum supported by Photoshop. Of course, a full 360x180 panorama would end up as 300000x150000 (45GP). Either way, most likely not on anyone's radar, even mine. I suspect at those resolutions a dedicated panoramatic head is required, and its associated stitching software.

Onto the procedure!

  1. Export from Autopano Giga in Radiance HDR format. I tried a few different options but in the end Radiance HDR provided the best compatibility in the next step. Time: ~12 hours
  2. Using VIPS, transform this .hdr into a BigTIFF file. This is done using the vips tiffsave command, which takes HDR but not OpenEXR (the two 32-bit formats supported by Autopano). Time: ~15 minutes
  3. Open the .tiff in Photoshop. Save as a .psb immediately. Time: ~1 hour

Overall, not a particularly involved process when you get it down. Unfortunately, it turns out that there was only one combination of likely hundreds of image processing programs and libraries, and file formats, which is capable of this. I expect to make more panoramas in this format, and most likely in the same size (using the same 135mm/3.5 prime lens), and so far this seems reliable enough on my system. I'll edit this answer later to show the completed panorama.

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_1. Merge to 32-bit HDR all 1400 bases

If you are only Tone Mapping (not fusing) in Photomatix I would suggest to merge to 32-bit HDR all 1400 bases first, since memory-wise a 32-bit HDRI is handled more economic in Photomatix than 3 LDRIs.

If your bracketed sets contain proper EXIF information I don't expect any exposure differences since Photomatix reads the EXIF data to retrieve the EV of each image.

  • Photomatix 'Batch Bracketed Photos'
  • Check 'Create 32-bit unprocessed merged file'
  • Output as .hdr or .exr
  • Check 'Skip HDR processing' (!) to skip any tone mapping / LDR output

_2. Stitch 3 low-res panoramas

  • Stitch the 0EV base images (JPG, TIF, not RAW) in PTGui/Autopano first
  • Output a low-resolution panorama, maybe as TIFF 8-bit
  • Stitch the -1.3 and +1.3 images by applying the 0EV-stitching template (strg +T in PTGui)

_2.A Merge 3 panorams to 32-bit HDRI

  • If you like and the RAM your machine offers allows it, you could merge the low-res panoramas to an 32-bit HDR image (hdr, exr)

_3. Find Tone Mapping setting you like using 3 low-res panoramas

  • Tone Map the three low-res panoramas (2.) or the 32-bit panorama (2.A) to find a setting you like in Photomatix
  • DO NOT check the 360 Degree option in Photomatix since you will be using these settings for the bases
  • Save the Tone Mapping settings as preset/xml in Photomatix Pro

_4. Tone Map bases using the settings

  • Tone map the 1400 32-bit bases from (1.) in Photomatix' batch using the preset/xml from previous step (3.)

_5. Stitch high-res panorama

  • Create empty project in Autopano/PTGui
  • Load the tone mapped bases from previous step (4.)
  • Apply the 0 EV template project
  • Save stitched gigapano as flattened PSB, 8-bit, no packbits

I only use PTGui, but I assume Autpano has the same possibility to apply a template project to loaded images of a panorama. So please replace 'PTGui' with 'Autopano';-)

  • This looks like it definitely has potential, especially considering that I do like Photomatix's tone mapping better. My main concern is that using batch processing will result in banding of the image - an image with lots of sky will be "darker" than an image with lots of shadows. Or can Photomatix always tone map the same way, regardless of content? – gjsmo Apr 27 '16 at 20:43
  • As I suspected, this results in very significant differences between images - particularly between those with sky and those without. Here is just an example where I aligned the images manually in Photoshop. I don't think Autopano can deal with this much exposure difference, and it doesn't look particularly good to apply the global preset to each image locally. – gjsmo Apr 30 '16 at 14:40
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With many of these suggested Programs you can ToneMap RAW unstitched Images and get a perfect result, that's the whole point (ease and exact results, indistinguishable from a single Photo).

Its been a while since I've used some of these Tools I'm suggesting, sometimes Bugs creap in an wreck the Feature you specifically downloaded for so YMMV. These are either free or have free Trials.

My Favorite (and I am recommending it both as a great Program and as your answer) is PTGui (many Updates since I last used it): https://www.ptgui.com/hdrtutorial.html - Uses GPU(s) and multiple CPU Cores for fast processing.

If you want to look further (don't know why) then I also (last I tried it) liked EasyHDR.

See: http://alternativeto.net/software/easyhdr-pro/ for EasyHDR and suggested (by that Website) alternatives, it can do LDR (single image).

Also look at the List at: http://wiki.panotools.org/HDR_and_Tonemapping_dialogs_in_detail which is a Wiki page from one of my favorites 'Pano Tools' - it lists the Features of various competitors (some of which can 'Stitch and ToneMap', what you want).

Most of those will chew up and spit out your puny Image collection, some don't go quite that big (but I've no control over what those Links suggest, only to offer that I've used some of the ones that others have suggested).

You really want a Program that supports multiple GPUs to speed up the calculations.

  • "(ease and exact results, indistinguishable from a single Photo)" - I do not have suitable example at my hand by it seems very likely to me that there is a plenty of ways in which tonemapped single images won't make a uniform pano and I am first of all thinking about image edges. Tonal curve is better in this regard but not effective. – Euri Pinhollow Apr 25 '16 at 18:41

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