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- Thread starter Pieter 12
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www.photo-digitaltransitions.com

When doing stitching with stitching you’re basically just making a physically larger virtual sensor.

For example if you stitch an IQ4 150mp ~51x40mm sensor to do a left-right stitch of +/- 12mm shift on the long side your virtual sensor size is now (51+12+12) x 40mm.

Got it. What I’d like to know is the then equivalent angle view for the lens.

When doing stitching with stitching you’re basically just making a physically larger virtual sensor.

For example if you stitch an IQ4 150mp ~51x40mm sensor to do a left-right stitch of +/- 12mm shift on the long side your virtual sensor size is now (51+12+12) x 40mm.

There are a few choices when converting angles of view with different aspect ratios. In @dougpeterson's example, since you're describing a 75x40 rectangle instead of a 51x40, you can use the diagonal or the long edge, and these will give different answers. The long edge is a 47% increase (75/51) = 1.47. The diagonal is a 31% increase. (85/65) = 1.31. With a larger aspect ratio like 75x40 (almost 2:1), the diagonal is probably what you care about, and so the angle of view would be that of a 50/1.31 = 38mm lens. That is, a single image from a 38mm lens, cropped to the same shape as the panorama, would have the same image, only with fewer pixels.

The formula is (equivalent focal length of panorama) = (focal length of taking lens)*(diagonal of single frame)/(diagonal of panorama)

Plugging in the numbers here looks like 38 = 50 * 65 / 85

Best,

Matt

(If you*really* want angles and not equivalent focal lengths, then it's 2*ArcTan( d / f ), where f is the focal length of the taking lens and d is the diagonal of the panorama.)

The formula is (equivalent focal length of panorama) = (focal length of taking lens)*(diagonal of single frame)/(diagonal of panorama)

Plugging in the numbers here looks like 38 = 50 * 65 / 85

Best,

Matt

(If you

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Thank you. Come to think of it, I thought there was a website where you could plug in the numbers and get equivalent focal length and angle of view.There are a few choices when converting angles of view with different aspect ratios. In @dougpeterson's example, since you're describing a 75x40 rectangle instead of a 51x40, you can use the diagonal or the long edge, and these will give different answers. The long edge is a 47% increase (75/51) = 1.47. The diagonal is a 31% increase. (85/65) = 1.31. With a larger aspect ratio like 75x40 (almost 2:1), the diagonal is probably what you care about, and so the angle of view would be that of a 50/1.31 = 38mm lens. That is, a single image from a 38mm lens, cropped to the same shape as the panorama, would have the same image, only with fewer pixels.

The formula is (equivalent focal length of panorama) = (focal length of taking lens)*(diagonal of single frame)/(diagonal of panorama)

Plugging in the numbers here looks like 38 = 50 * 65 / 85

Best,

Matt

(If youreallywant angles and not equivalent focal lengths, then it's 2*ArcTan( d / f ), where f is the focal length of the taking lens and d is the diagonal of the panorama.)

There is a lot of webpages offering ready made triangle calculators, too.

That’s exactly what the DT Visualizer (linked above) does.Thank you. Come to think of it, I thought there was a website where you could plug in the numbers and get equivalent focal length and angle of view.

Enter any combination of sensor, lens, and stitching configuration and it gives the AOV, equivalent focal length (based on vertical, horizontal, or diagonal) in another format. It also shows you the result visually.

Maybe you didn’t notice the Focal Length Visualizer as it’s the second such tool at the provided link?

Maybe I'm missing something here, but the tools seem to be limited to certain lenses and sensors, none of which I am using. I don't see the option of entering my own configuration(s).That’s exactly what the DT Visualizer (linked above) does.

Enter any combination of sensor, lens, and stitching configuration and it gives the AOV, equivalent focal length (based on vertical, horizontal, or diagonal) in another format. It also shows you the result visually.

Maybe you didn’t notice the Focal Length Visualizer as it’s the second such tool at the provided link?

Hello Pieter,Maybe I'm missing something here, but the tools seem to be limited to certain lenses and sensors, none of which I am using. I don't see the option of entering my own configuration(s).

I think you're referring to the

But if you scroll down from there, you'll discover the

Here's a screenshot: