Help with Panoramics...
Hello Dgriners,
As I've mentioned previously, I am spending a few weeks in Europe and come to you in need of help: I am trying to take panoramics of sites in Vienna, Austria, but am running into difficutly in the stitching phase. The pictures do not blend seamlessly and are thus rather dissatisfying. Any help, including links to other posts (though I have searched this forum) would be greatly appreciated.
I'll mention what I've been doing in case you notice anything that can be to blame:
1. Camera: Sony 717 on tripod
2. Settings: manual mode, manual wb, manual iso (100), manual focus (infinity)
3. Exposures: same settings for all pictures in the series (roughtly F4.0, speed 160)
4. Lighting conditions: mainly daylight
5. Overlap: 33-50%
Could the problem be that I do not change the exposure between phrames???
Thank you for your help,
Kevin K.
As I've mentioned previously, I am spending a few weeks in Europe and come to you in need of help: I am trying to take panoramics of sites in Vienna, Austria, but am running into difficutly in the stitching phase. The pictures do not blend seamlessly and are thus rather dissatisfying. Any help, including links to other posts (though I have searched this forum) would be greatly appreciated.
I'll mention what I've been doing in case you notice anything that can be to blame:
1. Camera: Sony 717 on tripod
2. Settings: manual mode, manual wb, manual iso (100), manual focus (infinity)
3. Exposures: same settings for all pictures in the series (roughtly F4.0, speed 160)
4. Lighting conditions: mainly daylight
5. Overlap: 33-50%
Could the problem be that I do not change the exposure between phrames???
Thank you for your help,
Kevin K.
0
Comments
You say that your panoramics didn't blend seamlessly. Is your only problem exposure? Or are you having problems with objects that did not blend well.
I am certainly not an expert on panoramics, but here is what i found worked best for me:
1. Horizontal stitching generally works better than a vertical stitch, because of issues with changing perspective.
2. Limit the overap to 10 - 20%.
3. Use a focal length that minimizes barrel/pin cushion distortion. If you are taking your photos on your maximum wide angle, you are probably getting some distortion at the edges. Take a look at lines that should be straight or verticle and see if they are curved or inclined (like the edge of a building, a verticle post, etc.). If you are getting this kind of "bending" at the edges, your stitch software will have a really hard time matching things up, especially if you are overlapping 30 - 50%.
4. Make sure you are panning absolutely horizontal to the horizon. This is easier said than done, but this helps enormously.
As far as the exposure is concerned, I usually do what you have done and use the same exposure for each photo. It depends on the differences between the light to shadows and how many photos I want to stitch.
My better panoramics were with a mid focal length, but a wide angle can work well if the edge being stitched is far in the horizon. The closer the objects, the more likely you will have some perspective distortion.
I hope this is of some help.
Regards,
Brad
P.S. What software are you using to stitch your photos? How about posting a sample of one that you don't like so that we can take a look.
www.digismile.ca
Most stitching problems boil down to three very common oversights - all easily controlled.
1. Exposures should be all done on full manual. This will ensure an even blend from shot to shot. If in doubt of what the proper exposure should be, take some test pics with either shutter or aperture priority to get a feel of where the correct and average exposure for the set should be. Hint... on the F-series cameras, the lens is sharpest at f/4 to f/4.5. I'd start there on Av, write the exposure settings down, then switch to M. Also, best to set focus to infinity (if outdoor pano), to insure no single shot is accidently focused onto a nearby shrub or something.
2. Wide shots don't stitch well due to barrell distortion. Since wide angle is the method most shoot at for panos, this will often confound the stitching software due to image distortion at the edges. This doesn't mean you need to shoot at the equivalent of 50mm all the time. Good (and free) software is available to de-barrellize the shots. Check out the PTLens plug-in. Many pano stitching software packages deal with this more or less automatically, if they are correctly set up. I use PanoramaFactory, which can correct for wide shots prior to stitching, but I prefer to do it manually in PTLens first. I have more control over the process that way. The big upside to a correctly de-barrellized pic is that stitching works much much faster, and is hugely more accurate.
Some parts of pics are just notoriously difficult to stitch. Foreground made up of grass or small planty material, or asphalt streets at the bottom of pics confuse software easily.
3. Parallax error. See this here for more info.
note... overlapping 50% can be counter-productive. I wouldn't overlap more than 30% - but do overlap at least 20%
Hope that helps.
"You miss 100% of the shots you don't take" - Wayne Gretzky
Might I also suggest software that makes your job easier. That is
Panorama Factory from Smoky City Design. I've seen a number of
panoramas put together with it and was impressed enough to buy it
myself. Very nice tool.
Ian
Brad,
Thank you for that great reply, it's certainly very helpful. My main problem appears to be with blending exposures (objects seem to blend rather well). This is most evident in the areas where the sky from one shot meets the sky of the following shot.
I will take into account your advice about the focal length issue, and reshoot to see what comes out.
In terms of software, I was using PS Elements 2. After some late-night research though, I found that many dgrinners use PanoramaFactory. I downloaded the trial version and it worked like a charm. I've included a test picture below, and as you can see the sky blends quite well - the only issue I've yet to resolve is that the left portion of sky is blown out (was originally light blue), so I'll try correct that. I also emailed Luben Solev, who recommended PF as well as software called PTGui, which I've yet to try out. Here is the picture, a pano of the Schoenbrunn Palace in Vienna, Austria:
Cheers,
Kevin K.
Hi David,
Thank you for the links and advice - looks like I've got a bit of learnin' ahead of me regarding barrel distortion and lens parallax. I will reshoot the pano once I've read all the info and see if I can't get better results. Also, I'll keep the overlap to between 20-30%. I also plan to buy a hot-shoe bubble/level as per the advice of Luben Solev.
Thanks again...cheers,
Kevin K.
You're right Ian, there seems to be a great thread developing here thanks to you and everyone else
Cheers,
Kevin K.
Nice panoramic too.
Ian