Check out this quick calculator for determining the proper angles to pan and tilt your camera for proper panorama overlap when shooting a multi-row panorama. Also calculate the resulting resolution and number of rows and columns needed for any desired field of view.
This tool was originally published and created for our large format astrophotography tutorial. I’ve found that it’s very helpful when configuring a panorama head to pre-determine the right angles of panning and tilting necessary to achieve adequate, regular overlap of individual panorama frames. It also calculates the resulting resolution of your panorama based on your desired output parameters. Just enter your gear details and the calculator will update in real time:
I recommend starting with about 50% overlap between frames. The output angles are calculated based on your camera, lens and whether your camera is mounted in portrait (vertical) or landscape (horizontal) orientation. The calculator assumes the same overlap percentage in both panning and tilting directions.
Once you’ve determined the degree values needed for your panorama, set your indexing head so that it sweeps that amount between each shot. These angles are also helpful for entering into PTGui’s panorama stitching software’s “Align to Grid” feature.
The default overlap is 50%. As you learn the capability of your gear and stitching software, it can be helpful to slightly reduce overlap in order to reduce the total number of frames necessary to cover any given field of view, but at a higher risk of potential stitching errors. I’ve successfully used about 30% overlap on certain panoramas and PTGui claims to be able to stitch with as little at 10%. If you’re just starting, shoot 50% overlap for the best results, especially with astrophotography panoramas.
Landscape or Portrait?
In the case of multi-row panoramas, if your overlap is consistent, the orientation of the camera doesn’t really matter. For any given final field of view for a multi-row panorama, either orientation will require approximately the same total number of photos. You might find that you prefer one orientation over the other, depending on your panorama head, lens, or camera design.
After trying both orientations for my setup, I found out that I usually prefer the landscape orientation because my camera’s LCD screen on my a7S only tilts for that orientation. That said, shooting in portrait allows me to shoot with less total number of rows in my panorama.
If you have any questions about the calculator or astrophotography in general, please feel free to comment below or contact me!
14 Replies to “Panorama Overlap Calculator”
Ian, have you ever done multiple shots for each, stacked, and then blended? For example, if I use a 40mm lens to shoot a 20mm scene vertically, it’s 3 rows and 5 columns. If I do the typewriter method and use a 13″ shutter speed and took 4 shots per position (1 stop noise reduction), it would be about 5 mins to do a column before the next column. so the difference in star position would be a little over a degree. Would that gap be too much for ptgui? Thanks!
Very cool resource! It looks like the megapixel estimate calculation isn’t working correctly. When you change the % of overlap, the MP estimate changes considerably. I don’t believe it should. If I’m using the same sensor, focal length, and output field of view (equivalent FL), then the MP should stay the same. Yes, more overlap means more frames, but using less of each one. Thoughts?
I don’t understand the point of the “desired equivalent focal length “? What does it do? I have already told the calculator that I have a crop sensor shouldn’t it be happy with that?
It’s just unfortunate naming. Instead of setting “output horizontal angle” (let’s say you want to get half-around panorama) you have to choose what lens you would use to make your desired panorama with one shot.
Thanks for the calculator. I was also wondering about star trails. I’m assuming that the field of view calculation is for the diagonal angle and not the horizontal angle. Right.
i am intrigued by this, but how do you deal with star movement. I can see using this technique during the day when you have enough light to shoot fairly quickly. but at night to do several hundred shots would take at least 1 hour if not more. So how do you stack your photos so as not to have star trails
Hi John, star movement is much less of an issue than you might think. If using a shutter time that follows a typical rule like the 500-rule or the result from my advanced shutter time calculator, exposure times can be reduced greatly when using a long lens like a 100mm (usually to only about 2-5 seconds). At that short of a shutter time, star trails are insignificant. That short of a shutter timer means it’s possible to shoot about 120 images in about 10-12 minutes. In that amount of time, the sky will only move about 2.5 degrees… small enough that a panorama stitcher can handle a seamless blend without noticeable artifacts.
Hi Ian, just ran the calculator and it is giving me a 9 column 10 row panorama. My question is regarding the tilt which is at 8.0 degrees. I purchased the same Desmond DMH-2 Tilt Head as you but there are no degree marks on the tilt portion of the head. Are you just eyeballing 50% overlap on LCD screen?
Do you generally shoot your panos left to right? That is what i end up doing, but I’ve wondered if I should be shooing Right to Left (or Right columns first, then moving progressively to the left), since the stars on the right will be disappearing under the horizon, and therefore possibly causing issues if the overlap changes as stars disappear.
Sort of. I always start my first row left to right. But then I zig-zag back and forth so the next row goes right to left. With enough experience, i’ve found that as long as you don’t allow too much time to pass between shots when shooting the horizon, stitching only rarely ever has issues with alignment. The more important thing to think about is consistent overlap angles and minimizing time gaps between exposures.