Which picture ratio?
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GadgetGuy
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Meta4
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Because you asked for it ....Would love to read it! Can you provide a link to it, please?
Skypixel 360° Images - WOW
Here's a more recent one: SkyPixel - Connecting Creativity
GadgetGuy
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Aspect Ratio
Think of this as the rectangular shape of your image stated in a ratio of length vs. width. DJI markets their superb DJI Phantom 4 Pro with a 20 megapixel sensor, but if you choose that sweet HD TV aspect ratio of 16:9 you are only achieving a little over 16.8 megapixel photos! Yes, I know that 16:9 is the same ratio as your flat screen HD tv but for photogrammetry we want to think less narrow mindedly. If you are reading this and you looked up the sensor dimensions for the Phantom 4 Pro above you’ll see it has a sensor that is 13.2mm by 8.8mm. 13.2/8.8 = 1.5. Those black bars above your 16:9 ratio image are missing data! For photogrammetry you always want to use the full ratio of your sensor. In nearly every case this will be the 3:2 aspect ratio. 3/2 = 1.5 = the same as your sensor calculated above. By choosing this ratio you will be able to capture the maximum amount of data in each image that your sensor is capable of. In the case of the Phantom 4 pro the 3:2 ratio corresponds to 5472 pixels by 3648 pixels = 19,961,856 pixels (Mega = millions) which is why DJI calls it a 20mp sensor.
Think of this as the rectangular shape of your image stated in a ratio of length vs. width. DJI markets their superb DJI Phantom 4 Pro with a 20 megapixel sensor, but if you choose that sweet HD TV aspect ratio of 16:9 you are only achieving a little over 16.8 megapixel photos! Yes, I know that 16:9 is the same ratio as your flat screen HD tv but for photogrammetry we want to think less narrow mindedly
. If you are reading this and you looked up the sensor dimensions for the Phantom 4 Pro above you’ll see it has a sensor that is 13.2mm by 8.8mm. 13.2/8.8 = 1.5. Those black bars above your 16:9 ratio image are missing data! For photogrammetry you always want to use the full ratio of your sensor. In nearly every case this will be the 3:2 aspect ratio. 3/2 = 1.5 = the same as your sensor calculated above. By choosing this ratio you will be able to capture the maximum amount of data in each image that your sensor is capable of. In the case of the Phantom 4 pro the 3:2 ratio corresponds to 5472 pixels by 3648 pixels = 19,961,856 pixels (Mega = millions) which is why DJI calls it a 20mp sensor.
Meta4
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You would think so but DroneDeploy don't seem to think it makes much difference and still use 4:3 even with the P4 pro.
3:2 aspect ratio update?
Just wondering if there are plans in the pipeline for the capture app to be able to utilise the the full 3:2 sensor size of a DJI P4P rather than 4:3?
forum.dronedeploy.com
I'm not sure what the other mapping apps employ.
