Request: concrete instructions on how to create HDR panos (bracketed)

[harryshin]

Request: concrete instructions on how to create HDR panos (bracketed)

by harryshin » Thu May 07, 2009 3:12 am

hi:

1. i just read the brief overview (in the documentation section) on how to create bracketed panos, which can then be used in something like photomatix.

2. problem: the description was too brief for a newbie like me (in re: autopanopro) to follow. thus, it would be great if someone can give me some basic concrete steps on how to produce / render bracketed panos.


thanks for the help. harry shin

[Nanard]

by Nanard » Fri May 08, 2009 6:55 pm

I know 3 different ways to combine Photomatix and autopano pro.
Let say you have 4 different views for your pano, each taken at 3 different exposures.

1) create HDR -> stitch -> tone mapping :
combine the different exposures for each view to obtain 4 HDR images with photomatix
create one HDR pano with autopano pro
tone map the hdr pano in photomatix

2) stitch -> hdr/tone map :
create 3 panos (one for each exposure) with auto pano pro, using the auto pano layer editor (group per speed for ex.)
combine the 3 panos in photomatix, create hdr and tone map

3) hdr/tone map -> stitching
for each view, create hdr and tone map in photomatix
stitch the resulting 4 tiff

I assumed here the starting images were tiff (or jpeg).
With raw images, it's a bit different.

Try the 3 methods and tell me want you think...

Bernard

[DrSlony]

by DrSlony » Fri May 08, 2009 7:22 pm

http://www.autopano.net/forum/p43849-2009-04-27-18-23-47#p43849
Know the strengths and weaknesses of each method, and work your way from there.

[Nanard]

by Nanard » Fri May 08, 2009 9:44 pm

Hi DrSlony,

Thanks for the pointers you provided.
I agree with the strengths and weaknesses you described , just some remarks:
. I tend to use smartblend only when the are moving 'objects', otherwise I prefer multiband
. did you try Photomatix 's strip by strip option to solve memory problems ?
You probably know Michael Freeman's excellent book on HDR photography...

Bernard

[Nanard]

by Nanard » Fri May 08, 2009 9:49 pm

../.. continued

Do you process raw files in a raw developper or in PM / Autopano ?
How would you compare Photomatix's exposure blending and Enfuse ?

Bernard

[DrSlony]

by DrSlony » Sat May 09, 2009 12:40 am

". I tend to use smartblend only when the are moving 'objects', otherwise I prefer multiband"
I always use smartblend, keeps things sharper in blended areas.

". did you try Photomatix 's strip by strip option to solve memory problems ?"
Yes, it also has its memory limits. The GUI mode using large file processing or batch processing doesn't work under wine, They assured me they will solve it in Photomatix 3.2 or 3.3. For now I am stuck with Photomatix CLI for large files. I prefer enfuse most of the time anyway.

"You probably know Michael Freeman's excellent book on HDR photography..."
Heard of Mastering HDR Photography and of Perfect Exposure, haven't read them yet.

"Do you process raw files in a raw developper or in PM / Autopano ?"
For best quality, always develop RAW files yourself, I do. I use RawTherapee.

"How would you compare Photomatix's exposure blending and Enfuse ?"
Very similar, but strictly exposure blending, not tonemapping.

[Nanard]

by Nanard » Sat May 09, 2009 3:57 pm

Hi,

"I prefer enfuse most of the time anyway."
You caught my interest conc enfuse, which I did not know, but I am a bit lost between Enblend, Enfuse, Hugin,..and AutoPano !
Would be nice if you could :
. give me a starting point for enfuse,
. explain how you combine enfuse and autopano pro ?

Bernard

[DrSlony]

by DrSlony » Sat May 09, 2009 4:34 pm

Sure, just first tell me whether you use windows, linux or mac :]

[Nanard]

by Nanard » Sat May 09, 2009 6:05 pm

Sorry, I forgot to mention that : windows XP

[DrSlony]

by DrSlony » Sat May 09, 2009 6:26 pm

". give me a starting point for enfuse,"
You can use EnfuseGUI http://software.bergmark.com/enfuseGUI/

". explain how you combine enfuse and autopano pro ?"
Because of the smartblend issue I mentioned in the post I linked you to before, for now I batch-enfuse all source images before stitching. I would usually prefer to enfuse the whole layers instead of individual images for reasons described here, but for now that's mostly impossible unless ghosting isn't an issue (on some landscape shots it isn't). Once smartblend2 is here, I I will probably blend exposures after stitching without worrying about ghosting.

I think the rest is described in those threads, feel free to ask if you don't find something.

[Nanard]

by Nanard » Sat May 09, 2009 9:04 pm

DrSlony,

Very interesting, will have a try, thanks !

Bernard

[harryshin]

by harryshin » Sun May 10, 2009 4:55 am

hi:

1. thanks for the various posts.

2. after reading bernard's suggestion and glancing at Freeman's book today, it all started to make sense (at least for me) in re: making the HDR pano by first creating individual ".HDR" files and then putting those files into autopanopro--> making a .HDR pano--> then tonemapping in photomatix. Problem: i'm able to import the .hdr files into autopanopro and i can see them in the left / group window. however, when i go to make the panorama, the .hdr files seem to merge appropriately (ie stitching quality is noted to be "good") and it appears that there is a panoramic image, but the problem is that i literally can't see the image. rather all i see is a very dark grey rectangular "image". when i then render that grey image and then move it into photomatix, i end up with this very odd black/ white pencil drawing image.

3. obviously i'm doing something wrong here, but the above workflow produces nice HDR panos when using realviz stitcher. can someone please tell me what i'm doing wrong?


thanks for the help. harry

[DrSlony]

by DrSlony » Sun May 10, 2009 2:00 pm

APP-1.4.2, if I remember correctly, could only render HDR if the input files were HDR too, if you used smartblend. Since this is what you are doing and you get a black render (screenshots please!), then I assume you're using 2.0.0. I don't remember what requirements 1.4.2 had for multiband.
I haven't tested stitching HDR files in 2.0.0 yet.

[harryshin]

by harryshin » Mon May 11, 2009 4:19 am

hi:

1. i used both APP 1.4 and 2.0--> both were problematic in producing a proper .HDR file. both were able to stitch the individual .HDR files, but the APP 2.0 produced a basically black pano, which when tonemapped in photomatix produced an odd monochrome type image. what's interesting is the APP1.4 produced a "normal" looking .HDR pano (ie very contrasty image). i thought this would then turn out normal when tonemapped, but it also produced an unusual tonemapped image; not monochrome this time but an abnormally contrasty image for something that was tonemapped.

2. any further suggestions welcomed. again, as per my original post, i believe this problem isn't due to my knowledge of photomatix nor the source images, because i've been able to create a proper HDR pano via realviz stitcher. thus, there is something wrong with APP or more likely, something i'm doing incorrect in the workflow or settings. problem is, there is apparently no documentation in the APP manual on how to do this.


thanks. harry shin