I saw it mentioned somewhere that the P4P's sensor is 3:2 and so shooting 3:2 gives the fullest, 20MP picture. However, testing this at home, 16:9 seems to give the largest FOV and both 4:3 and 3:2 seem to be (at least on the picture display) crop and zooms of the 16:9 picture. So which ratio actually gives the largest picture?
Which picture ratio?
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Meta4
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It would be surprising if 16:9 has a different FOV .
The numbers suggest that 16:9 is just 3:2 with the top and bottom cropped
Image Size
3:2 Aspect Ratio: 5472 × 3648 = 20 MP
4:3 Aspect Ratio: 4864 × 3648 = 17.7 MP
16:9 Aspect Ratio: 5472 × 3078 = 16.8 MP
4:3 Aspect Ratio: 4864 × 3648 = 17.7 MP
16:9 Aspect Ratio: 5472 × 3078 = 16.8 MP
What you have heard mentioned is correct. You need to question your test procedure, what it seems to be it can't- 16:9 and 3:2 have the same pixels across the largest dimension of the frame so diagonally measured FOV must be greater for 3:2. Most reliable way for you to confirm is to look at the image pixel dimensions.
I just noticed meta has given you the numbers in his post.
I just noticed meta has given you the numbers in his post.
16:9 will capture a much wider area than 3:2, but a little shorter. So each setting has a purpose. I fly a very large commercial property that is about a block wide and 3/4 of a mile long. They don't want to pay an upcharge for any mapping software use. But I do a stitch of the entire property out of 15 pics shot in a straight line. I can do this at 16:9 because I can just barely get the width of the property in at max altitude of 400ft. I can not do it at 3:2 or 4:3. The property width won't fit
Meta4
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The idea that 16:9 is wider than 3:2 is an illusion.
16:9 will capture a smaller area than 3:2
The images are the SAME width
A 16:9 image is the same as the 3:2 image except that a strip 285 pixels wide has been cut off the top and bottom.
If you want the biggest possible original image and preserve your options for cropping, there is only one choice .. 3:2.
I have flow the same ginormous construction property twice a month since August. I started with the P3P with a considerable wider FOV. When I started this project, I wanted to pre-program some Litchi missions, which I was positive I would have to adjust after the first flights. I asked here on PP how to do a FOV calculation. A guy on here sent me an Excel file. I wish I could remember his name, because it is simple, but genius work.
I measured the property on Google earth. I calculated the number of pics to get a good stitch and programmed Litchi according to the files results. It was PERFECT the first time.
Fast forward a bit. I bought the P4P. I took his file, looked up the FOV of the P4P, and copied his math over a few columns changing the P4P FOV
@#$%, I was not going to be able to use my new bird to fly this property. The math said it would not fit. But wait... there are different FOV's on the P4P. I plugged them in. At 400ft it said the 16:9 would capture the widest part of the property with only about 2ft to spare. The rest of the property with about 15 ft to spare. 3:2, and 4:3 would not capture it.
So... that is the math of some guy I don't know. And my adaptation of the file for the P4P. Does it work?
I reset the Litchi mission for the height to capture the width of the property in 16:9 and changed the numbers and spacing of waypoints to capture the difference in the height of the 16:9 pic, with 1/3rd overlaps. It was also perfect the first time.
The second time I flew the property, after buying the P4P, I had the site managers national boss yaking in my ear the hole time I was trying to fly. Distracted, I did not switch to 16:9 for the mission. (normally I fly 3:2) The property DID NOT fit in the frame flying 3:2. The pics would not even stitch.
So I promise, in reality, 16:9 shoots a wider image than 4:3 or 3:2. There is nearly a 30ft width difference at 400ft between 16:9 and 3:2 and nearly double that between 16:9 and 4:3.
I attached the ziped file to review. Save it, it is awesome. Using Google Earth measurements of ground captured, this file is SPOT ON ACCURATE for both the P3P and the P4P
I think the difference your seeing is between the lense on the P3P and the lens on the P4P. The P4P lens is slightly longer or more telephoto than the lens on the P3P. That's why I think your shot is harder to get with your P4P because it's closer up. Because the sensor should be recording the same width at 16:9 as it is when in 3:2. When you change these two formats it still should be using the entire sensor to record image. It's just a slightly more telephoto lense that is causing it to seem like it's shooter wider to you maybe. That might of been in the software doing this calculation too possibly.
Meta4
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And I promise that 16:9 is NOT wider than 3:2. It's just not possible as 3:2 is already using the max width.
The actual numbers tell the story.
Image Size
3:2 Aspect Ratio: 5472 × 3648 = 20 MP
4:3 Aspect Ratio: 4864 × 3648 = 17.7 MP
16:9 Aspect Ratio: 5472 × 3078 = 16.8 MP
btw .. all that calculating sounds like too much work and too many ways for an error to creep in.
Why not just use Dronedeploy to do the flying for you with lots of overlap.
It does the calculating, it does the flying and shooting.
You can still do the stitching.
.
I'm kinda torn between 3:2 and 4:3 because at the larger 'full sensor size' I'm seeing more distortion than at 4:3.
You'll note that I put 'full sensor size in inverted commas because the DNG and JPEG output from the P4P is far from the full sensor size - it's processed/cropped in camera to compensate for barrel distortion and vignetting - what we actually get is about 17.5mp images stretched back to 20mp and this is where I suspect the distortion is creeping in
You'll note that I put 'full sensor size in inverted commas because the DNG and JPEG output from the P4P is far from the full sensor size - it's processed/cropped in camera to compensate for barrel distortion and vignetting - what we actually get is about 17.5mp images stretched back to 20mp and this is where I suspect the distortion is creeping in
trying to make a little sense of my last post, please see the attached image
The outer image is the photo the sensor actually records viewed in a raw viewer which disregards any DJI embedded'crops' recorded in the DNG file (I use UFRaw but there are others) and is as expected a full 5472 × 3648 = 20mp -
The inner red framed image is what the Phantom 4 Pro outputs as a full 20mp image but is only (approximately) 4721 x 3147 = 15mp (this area does vary from shot to shot) It's clearly been processed to remove barrel distortion and then cropped.
Both are supposedly unedited but the sky in the DNG is considerably lighter than in the raw - which is actually about 1 stop under exposed. My guess is that this allows DJI a little more chance of preserving highlights in the final output
What we are seeing as 20mp shots are very definitely not 20mp shots though!
If anyone wants to play with the original image to show that I'm not deliberately manipulating it - please ask, I'll upload it to my server
The outer image is the photo the sensor actually records viewed in a raw viewer which disregards any DJI embedded'crops' recorded in the DNG file (I use UFRaw but there are others) and is as expected a full 5472 × 3648 = 20mp -
The inner red framed image is what the Phantom 4 Pro outputs as a full 20mp image but is only (approximately) 4721 x 3147 = 15mp (this area does vary from shot to shot) It's clearly been processed to remove barrel distortion and then cropped.
Both are supposedly unedited but the sky in the DNG is considerably lighter than in the raw - which is actually about 1 stop under exposed. My guess is that this allows DJI a little more chance of preserving highlights in the final output
What we are seeing as 20mp shots are very definitely not 20mp shots though!
If anyone wants to play with the original image to show that I'm not deliberately manipulating it - please ask, I'll upload it to my server
You are skimming my post, not reading.
I clearly state the differences in the FOV between the P3P and P4P and the difference is also in the calculation file. Its 94° and 84°I agree, it's entirely feasible that we get a slightly wider field of view at 16:9 because there is much less distortion for the camera to correct and can use almost edge to edge data
And I promise that 16:9 is NOT wider than 3:2. It's just not possible as 3:2 is already using the max width.
The actual numbers tell the story.
Image Size
3:2 Aspect Ratio: 5472 × 3648 = 20 MP
4:3 Aspect Ratio: 4864 × 3648 = 17.7 MP
16:9 Aspect Ratio: 5472 × 3078 = 16.8 MP
btw .. all that calculating sounds like too much work and too many ways for an error to creep in.
Why not just use Dronedeploy to do the flying for you with lots of overlap.
It does the calculating, it does the flying and shooting.
You can still do the stitching.
.
You are skimming my post and not reading.
I clearly state above, the client would not pay my charge for using DroneDeploy. Not stated above, but they would pay my smaller charge for MME either. DD is far from cheap. At this size, MME is not free. DD does not give it away. Neither do I. But the "magic" is, that FOV file is spot on accurate. Litchi cost $25 forever. And using the calculations in the FOV file, I can zip out a Litchi mission that is perfect to use over, an over, and over again.
But to your other point, forget the file. From ACTUAL bird-in-the-air results:
I can fit the width of the property in at 360ft with the P3P at 4:3
I CAN NOT fit the width of the property in at 400ft, with the P4P at 3:2 or 4:3
I CAN fit the width of the property in at 400ft with, the P4P at 16:9
Repeat for effect
I CAN NOT fit the width of the property in at 400ft, with the P4P at 3:2 or 4:3
I CAN fit the width of the property in at 400ft, with the P4P at 16:9
You can tell me the sky is green all day long. But when I go out side, I can see that it is blue
Actually that's not correct
Try this little experiment...set your P4P up on a table or something and take two photos - one at 3:2 and one at 16:9 and compare them - the 16:9 has a slightly wider field of view - I've just tried this to confirm my thoughts (above)
Meta4
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Actually Dronedeploy DOES give it away.You are skimming my post and not reading.
Their app is free to use and you can do the stitching yourself.
Meta4
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If you are using the same fixed lens and the same sensor but cropping the top and bottom to get 16:9, there is no way that one image will have a wider FOV than the other.
So here's green sky - straight from the camera except for the labels.
Tell me which image has a wider field of view?
Two identical shots (drone on a small table) showing edge detail of photo - 16:9 on the left, 3:2 on the right - the 16:9 has a couple of extra inches at either edge at a distance of approx 10' which could theoretically translate to 160 inches (about 13') at a distance of 400'
and what the sensor actually recorded for the 16:9
As you can see, neither shot is using the full width of the sensor - the DNG files have already been 'edited' so it's entirely feasible that we see a variation between the end results
Adobe Camera raw running without any presets/lens adjustment profiles etc (which is presumably applying a DJI embedded preset also sees slightly more than the 'straight out of camera' jpeg - edited to add the 3:2 raw as well - you'll see that the two are slightly different - this should not happen with a raw
The following discrepancies also appear to be present
The white balance of the totally untouched raw is 5057, Adobe interprets it as 4900
The 'full' raw has quite bad fringing/Chromatic abberration - these have disappeared in Adobe raw
As mentioned above, the 'full' raw file is underexposed - presumably to try and reduce the above fringing
The barrel distortion in the 'full' raw has already been corrected by the time we view it in Adobe raw
There is something fishy going on here and the raw file we are viewing in viewers like Adobe Camera Raw is not actually a raw file at all - the fact that the camera's software can perform this correction real time at 60fps is really impressive though
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This confirms what I've seen as well. While I agree with Meta4 that DJI's quoted resolutions would suggest 3:2 is 16:9 with more pixels top and bottom, that isn't what actual shooting bears out. In actual shooting, 3:2 is significantly narrower width-wise and slightly shorter height-wise than a 16:9 picture... and this is absolutely baffling.
