Real-time image based lighting in software using HDR panoramas::
We present a system allowing real-time image based lighting based on HDR panoramic images [Debevec 1998]. The system performs time-consuming diffuse light
http://portal.acm.org/citation.cfm?id=604527HOME |
Background - I think I've got HDR down, and I've definitely got panoramas down. I use PhotoShop CS3 for the HDRs and I use AutoPano Pro to create panoramas.
I shoot RAW and open all the photographs with the same settings for the panorama. I then export them as 16-bit TIF files from PhotoShop's Camera Raw algorithm, making sure that they are ALL set to the same temperature, tint, contrast, etc. so that they match up as well as possible in the panorama software.
Problem - However, for any of you that do panoramas, especially ones that are 160+° across, you probably know that a single exposure setting can be a nightmare, especially if there's sky, because of the variation in illumination across the scene. I try to set my exposure so that the meter is never completely on one side or the other across the scene, but the camera often indicates there's as much as a 4-stop difference that I should be taking into account.
HDR Panorama Photography | panoHead - East Bay Area - Oakland CA::
panoramas. this site is for panoramas in all shapes and sizes. it's a sister site to wiredEye.net these images are all based on the same panorama
http://panohead.net/HOME |
Solution? - Apple just released new computers yesterday and I've ordered me a nice 8-core 2.8 GHz machine that I'll be loading with 6 GB RAM and 1.32 TB of hard drive space and a nice 30" monitor, so I will finally have hardware that will allow me to do what I propose:
Is it feasible to do an HDR panorama? Besides a boat-load more time and processing power, there are some practical issues that I see due to two different possible workflows:
First, you could do an HDR shot for EACH image section of the panorama. This means as you take the panorama, for each "location" within the field of view, you take your 2, 3, 4, etc. exposures with the different shutter speeds before moving onto the next frame of the panorama. Then during processing, you create the HDR of each frame and save it before importing it into the panorama software. The problem with this is ensuring the the HDR is processed the SAME way for EACH frame. Which I think would be very difficult.
Second, you could do your panorama and either go through the entire field with one setting, change it, and go through the field again, or take the shots as I said for the first method ... it doesn't matter here, though doing it the way as in the first method would probably be more consistent. You then stitch the panorama normally, creating N panoramas were N is equal to the number of shutter speeds for the HDR. Then, you merge those N panoramas into an HDR image. The problem here is ensuring that the panorama projection is the SAME for EACH panorama, otherwise there will be projection offsets that aren't uniform across the field.
Question - So ... has anyone attempted to do this? Can it be done? Can you think of a better way than either of my proposals, or think of solutions to the problems stated, or think of other potential problems I haven't thought of?
i've done an hdr panorama, it didnt turn out great though because you'd need to make sure that all the frames look the same as far as brightness
http://en.wikipedia.org/wiki/Image:False_Creek_at_Night_HDR.jpg
looking for something else - I came across this... may or may not be helpful...
at least in deciding if it is possible..
again, just a thought...
I've never done a panorama before but why cant you just set up your tripod, bracket exposure, then 3 clicks, rotate head on tripod to new position, 3 clicks again, etc. Then stitch them together, open in Photomatix and create the HDR.
http://www.flickr.com/photos/inexistentia/370271696/
Shaun loves his HDR panos. Somewhere in his flickr stream he meantioned which software he was using. I'll ask him when he's next online and if this thread is still going i'll let you know. But it takes care of everything. All you need to do is manually bracket your exposures as you're going through and the software stitches straight to HDR. Tonemapping needs to be done after as far as I remember.
Quoting myself, but he says he uses Autopano pro to go straight to HDR.
Easier said than done. That is a sweet sample on WIKI, oh and congratulations on your new Mac! (put 8 gigs in it, 1 per core) please report back as your mission unfolds.
Thanks, I'm sure I'll post my first "successful" attempt with some details. As to the computer ... yeah, I'm psyched! :drool: Too bad the graphics card (nVidia GeForce 8800 GT) puts an additional 3-5 weeks on delivery from the 1-2 days with the stock card. Sigh. As for the RAM, the extra 4 GB is $200 (2x2GB). Adding another 2 GB (2x1GB) is $130, the price of another 500 GB hard drive. I'm currently operating on 1.5 GB of RAM and so this will be a huge increase. I need to see what I actually use on the new computer before I add more, and by then the price will go down. When all is said and done, this set-up will have cost me $5.25k, so I'd rather put RAM on my birthday wish list than jack up the price on this purchase even more past my intended budget (I'm $530 over).
i've done an hdr panorama, it didnt turn out great though because you'd need to make sure that all the frames look the same as far as brightness
I'm not sure to what aspect you're referring -- are you talking about doing it via my method 1 or 2? If 1, I understand, and hence my main concern with that method. If 2, then I don't understand unless you were not using a manual exposure and keeping it the same per panoramic image across the entire field (as in one panorama at f/5.0 1/125-sec, another at f/5.0 1/80-sec, and another at f/5.0 1/150-sec). If you kept the exposure the same, you shouldn't have a problem in terms of brightness. Digital Urban: HDR Panorama with the Lumix FX-50::
Jul 24, 2007 whats your production process behind that hdr panorama? what soft do you use to stitch It has some of the best images i have ever seen.
http://digitalurban.blogspot.com/2007/07/hdr-panorama-with-lumix-fx-50.htmlHOME |
Quoting myself, but he says he uses Autopano pro to go straight to HDR.
D'oh! You're right! I didn't realize that Autopano Pro has that feature, but I did some digging, and ... http://www.autopano.net/wiki/action/view/Bracketed_panorama :hail:
That's a great shot! I'd love to know his method.
As I said to Sideburns, my concern is for when I don't have a tripod. If I do have a tripod, then I agree that it probably won't be an issue - the spherical projection should be the same if the bracketing is done on each shot. I may just have to suck it up and say that I can't do this hand-held.
I think that's pretty much how it looks.
It's not as difficult as it sounds.
Easier said than done. That is a sweet sample on WIKI, oh and congratulations on your new Mac! (put 8 gigs in it, 1 per core) please report back as your mission unfolds.
-Shea :D
Two things I thought of that might make it easier:
1) leave the exposure the same for all the shots. You'd have to find a middle ground so as not to have any blow outs, but you might end up with a bit of lost detail throughout. It's hard enough on one frame, I can't imagine it's easy accross several.
2) When messing with your RAW's, create images of each section of the pano that are overexposed by 2 stops, and underexposed by 2 stops. I don't use RAW all that much (something about to change once I cough up the bills for CS3), so I'm not positive how much leeway you have there. If you can just do that, it would be like doing a normal pano and you won't have to deal with a bunch of bracketed images that might be off a hair here or there.
If you used AEB for all your shots, and didn't move the camera at all (like using a timer)...then all of the shots should be distorted the same (if they need to be), and you should be able to just stitch them all together ,and then merge the 3 panos to HDR.
http://www.flickr.com/photos/inexistentia/370271696/
Shaun loves his HDR panos. Somewhere in his flickr stream he meantioned which software he was using. I'll ask him when he's next online and if this thread is still going i'll let you know. But it takes care of everything. All you need to do is manually bracket your exposures as you're going through and the software stitches straight to HDR. Tonemapping needs to be done after as far as I remember.
That's a great shot! I'd love to know his method.
I've never done a panorama before but why cant you just set up your tripod, bracket exposure, then 3 clicks, rotate head on tripod to new position, 3 clicks again, etc. Then stitch them together, open in Photomatix and create the HDR.
As I said to Sideburns, my concern is for when I don't have a tripod. If I do have a tripod, then I agree that it probably won't be an issue - the spherical projection should be the same if the bracketing is done on each shot. I may just have to suck it up and say that I can't do this hand-held.
You have multiple exposure groups, make those groups into panoramas, bring the panos into your HDR software, combine them, do whatever else needs to be done with them, finished. It's not as difficult as it sounds.
My concern is that the panorama software will spherically project the panorama to correct for various things, and the center of that projection may change. I admit, I haven't tried this under the panorama software I use now, but in the past this has been an issue for me when trying to align similar panoramas.
Hi guys, sorry to join this a little late...I don't normally venture too far from the landscape forum but just seen this. This was my first and only attempt at a pano, I went hdr because the foreground was very dark and although the sun was covered by clouds it was setting behind the tree, so the sky was quite bright. I didn't want to use filters because of the chance of darkening the tops of the hills.
It's 9 shots (x3 bracket exposure) in portrait 180 degrees, not really happy with the comp but as I said it's a first try at panos. I used the Panorama factory, Photomatix and cs2 to process.
http://www.takingthepic.co.uk/Forum%20Pics/sycamore%20gap%20pano%20portrait%20copy2.jpg
Ken.
If you used AEB for all your shots, and didn't move the camera at all (like using a timer)...then all of the shots should be distorted the same (if they need to be), and you should be able to just stitch them all together ,and then merge the 3 panos to HDR.
I'm hoping that's the case. The only problem with that is while some panoramas are planned and I can take my time and have a tripod to set up and all that, it's not always the case.
I guess I'll have to experiment unless some other folks can offer advice on the case of a hand-held.
well then i'd have to make 3 identical panoramas, and thats difficult as well
I've never done a panorama before but why cant you just set up your tripod, bracket exposure, then 3 clicks, rotate head on tripod to new position, 3 clicks again, etc. Then stitch them together, open in Photomatix and create the HDR.
Like I said, it's not as difficult as it sounds.
You have multiple exposure groups, make those groups into panoramas, bring the panos into your HDR software, combine them, do whatever else needs to be done with them, finished. It's not as difficult as it sounds.
http://www.flickr.com/photos/inexistentia/370271696/
Shaun loves his HDR panos. Somewhere in his flickr stream he meantioned which software he was using. I'll ask him when he's next online and if this thread is still going i'll let you know. But it takes care of everything. All you need to do is manually bracket your exposures as you're going through and the software stitches straight to HDR. Tonemapping needs to be done after as far as I remember.
i've done an hdr panorama, it didnt turn out great though because you'd need to make sure that all the frames look the same as far as brightness
That's why you HDR last.
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