14mp not 20mp

[ryanmanchester]

(Copied from fb)

P4P+ doesn't seem to be the 20mp camera as claimed.

I must say that it has been disappointing to find that my new P4P+ "20mp camera" is an interpolated image from approximately just a 14mp area of the sensor.

Looking at my 2:3 format RAW images, while bypassing the DJI lens correction profile, I see the "full" image as captured by the 2:3 format sensor.

Sadly, this shows that the lens used for this camera, fails to provide and image circle large enough to cover the entire sensor and this results in black corners and image quality loss towards those corners.

DJI's lens correction profile (that is applied to JPGs in camera & automatically to RAW images in some converters) makes distortion corrections and crops a smaller portion of the image to be rid of the dodgy corners. This cropped image is approx 4829 x 2948 pixels.... far less than the claimed 5472 x 3648 in the specifications.

This lower resolution image in then interpolated (enlarged) back to the claimed 20mp size. This is done both to the JPGs and also to the RAW images in those converters that automatically apply the profile.

I'm sorry DJI, but that IS NOT the same as providing the user with an effective (and of course "usable") 20mp of image data to work with.

Please understand that I have not set my expectations too high for a "consumer grade" camera on a drone. I understand that it will never match the quality of a DSLR or similar mirrorless, but I do expect to get the use of an "effective 20mp" of sensor data when the specifications tell me just that!

 

[Meta4]

(Copied from fb) P4P+ doesn't seem to be the 20mp camera as claimed.
...

I'm sorry DJI, but that IS NOT the same as providing the user with an effective (and of course "usable") 20mp of image data to work with.
Please understand that I have not set my expectations too high for a "consumer grade" camera on a drone. I understand that it will never match the quality of a DSLR or similar mirrorless, but I do expect to get the use of an "effective 20mp" of sensor data when the specifications tell me just that!

I've read this same complaint from pixel peepers a number of times but it makes no difference to my photography.
The P4p camera is outstanding and you won't find a better camera in the air for even 4 times its price.
This thread offers some idea of how good the camera actually is: DJI Phantom 4 Pro image versus Canon 5DIII w/ 16-35 f/4
Or look at a couple of great images I've shot on a big screen:
Shipping 2017 - Above & Beyond Photography
Shipping 2017 - Above & Beyond Photography
It's all about results. Now .. what was that complaint again?

 

[KevMo Photog]

(Copied from fb)

P4P+ doesn't seem to be the 20mp camera as claimed.

I must say that it has been disappointing to find that my new P4P+ "20mp camera" is an interpolated image from approximately just a 14mp area of the sensor.

Looking at my 2:3 format RAW images, while bypassing the DJI lens correction profile, I see the "full" image as captured by the 2:3 format sensor.

Sadly, this shows that the lens used for this camera, fails to provide and image circle large enough to cover the entire sensor and this results in black corners and image quality loss towards those corners.

DJI's lens correction profile (that is applied to JPGs in camera & automatically to RAW images in some converters) makes distortion corrections and crops a smaller portion of the image to be rid of the dodgy corners. This cropped image is approx 4829 x 2948 pixels.... far less than the claimed 5472 x 3648 in the specifications.

This lower resolution image in then interpolated (enlarged) back to the claimed 20mp size. This is done both to the JPGs and also to the RAW images in those converters that automatically apply the profile.

I'm sorry DJI, but that IS NOT the same as providing the user with an effective (and of course "usable") 20mp of image data to work with.

Please understand that I have not set my expectations too high for a "consumer grade" camera on a drone. I understand that it will never match the quality of a DSLR or similar mirrorless, but I do expect to get the use of an "effective 20mp" of sensor data when the specifications tell me just that!

This has been posted many times in last 10 months or so. But find me a better camera at this price point though! I'm still blown away every day how freaking clear this lens and sensor are for as tiny as it is. And I'm a pretty picky pro portrait photog for 31 years. LOL

 

[tml4191]

(Copied from fb)

P4P+ doesn't seem to be the 20mp camera as claimed.

I must say that it has been disappointing to find that my new P4P+ "20mp camera" is an interpolated image from approximately just a 14mp area of the sensor.

Looking at my 2:3 format RAW images, while bypassing the DJI lens correction profile, I see the "full" image as captured by the 2:3 format sensor.

Sadly, this shows that the lens used for this camera, fails to provide and image circle large enough to cover the entire sensor and this results in black corners and image quality loss towards those corners.

DJI's lens correction profile (that is applied to JPGs in camera & automatically to RAW images in some converters) makes distortion corrections and crops a smaller portion of the image to be rid of the dodgy corners. This cropped image is approx 4829 x 2948 pixels.... far less than the claimed 5472 x 3648 in the specifications.

This lower resolution image in then interpolated (enlarged) back to the claimed 20mp size. This is done both to the JPGs and also to the RAW images in those converters that automatically apply the profile.

I'm sorry DJI, but that IS NOT the same as providing the user with an effective (and of course "usable") 20mp of image data to work with.

Please understand that I have not set my expectations too high for a "consumer grade" camera on a drone. I understand that it will never match the quality of a DSLR or similar mirrorless, but I do expect to get the use of an "effective 20mp" of sensor data when the specifications tell me just that!

There is no doubt that the p4p camera is one of a kind for the price range, but I guess this guy is basically talking about false advertising.

 

[With The Birds]

There is no doubt that the p4p camera is one of a kind for the price range, but I guess this guy is basically talking about false advertising.

Agreed- that does seem to be the point. Hopefully the next model phantom will have a better lens.

I wouldn't be happy paying for a high boost turbo engine in a car to find the ECU reduced the torque to protect an inadequate transmission or clutch plate.

 

[MikeON]

I've been trying to duplicate Ryan's results using Adobe Camera Raw 9.1.1 and the P4P profile posted on this forum:
Adobe lens profile for P4P posted
When I click on "Enable Lens Profile Corrections", the image corners brighten somewhat, and the image stretches into the corners an almost imperceptible amount. The corners are nowhere near black before applying the profile.
What profile is Ryan using? Has it already been applied to my DNG files before they get to Camera Raw?

 

[andy_k]

Has it already been applied to my DNG files before they get to Camera Raw?

The short answer is 'yes' - it's automatically applied in Adobe Camera Raw but not other raw editors (rawthrapee) - you can see the profile details if you click on the lens section of ACR

 

[andy_k]

I've read this same complaint from pixel peepers a number of times but it makes no difference to my photography.

So, it's a case of 'I'm alright Jack'

It matters if you are regularly scaling/resizing your images - the 'raw' file you are working with has already been destructively edited and scaled by approximately 25% - that's not a good starting point. This same destructive edit adds an often unwanted colour profile/highlights tweak that matters to some people.

Yes, it's about results but raw files are all about non destructive edits of what the camera actually recorded - DNG files are meant to be digital negatives. The sensor information is there and can be recovered using alternative software. The lens profile that is automatically applied is in many people's eyes a poor one - that's where the complaint is.

 

[KevMo Photog]

There is no doubt that the p4p camera is one of a kind for the price range, but I guess this guy is basically talking about false advertising.

Well that really depends on how you clarify! They are actually using all 20mp to get the corrected image to work like it does! This will improve as time goes on I'm sure. But for now it's just what we have.

 

[andy_k]

Well that really depends on how you clarify! They are actually using all 20mp to get the corrected image to work like it does! This will improve as time goes on I'm sure. But for now it's just what we have.

not really, they are using about 17mp, cropping/correcting them down to 15mp and then resizing to 20mp

 

[KevMo Photog]

not really, they are using about 17mp, cropping/correcting them down to 15mp and then resizing to 20mp

But, if the sensor was not as large as it is they would not have room to do what they are doing to correct the image imo. I could be wrong here.

 

[Meta4]

I haven't seen anyone demonstrating how this terrible flaw affects their photography and how they are unable to get the shots they want because of it.

 

[andy_k]

a physically smaller sensor would allow the lens to utilise more of it - the edge pixels are distorted and suffer from vignetting - they are effectively disposable.

The ideal solution would be a bigger camera but that adds all sorts of other issues

 

[andy_k]

I haven't seen anyone demonstrating how this terrible flaw affects their photography and how they are unable to get the shots they want because of it.

What's wrong with this workflow? Tip....if you don't know the answer just ask any photographer

Take photograph using 20 mp sensor - shoot raw as this allows non destructive editing

Perform a series of 'destructive' edits which culminates in cropping the image to approximately 15mp

Resize image to 20mp

Start on your process of 'non destructive' edits in Adobe Camera Raw

 

[Meta4]

What's wrong with this workflow? Tip....if you don't know the answer just ask any photographer
Take photograph using 20 mp sensor - shoot raw as this allows non destructive editing
Perform a series of 'destructive' edits which culminates in cropping the image to approximately 15mp
Resize image to 20mp
Start on your process of 'non destructive' edits in Adobe Camera Raw

Show me some photos that should have been great but were ruined because of this "problem"

 

[andy_k]

Show me some photos that should have been great but were ruined because of this "problem"

I see you've chosen not to answer the workflow question

it's not about ruined versus great - that's a silly point to try and prove

The photos are good but the additional work required to get them to a standard that I am happy to send to print is more than should be necessary or that we were led to believe when we read the spec sheet. Mist people assumed that a 20mp sensor would turn out 20mp images - this one doesn't.

Looking at them on a screen makes no difference because most screens are pretty crap at displaying images but......when you send an image to a magazine/printer, they do not want (many will not accept) images that have been enlarged by 25% in the production/editing stage so....it may not have any effect on your life but the process is flawed and it does impact other people - you don't seem to be able to accept that.

 

[Meta4]

it may not have any effect on your life but the process is flawed and it does impact other people - you don't seem to be able to accept that.

Exactly right ... it has no impact on my photography at all and despite the protesting, I'm still not able to see any evidence that it has any actual, real negative impact on anyone else either.
But that's just my opinion ... if it pains you to know that DJi have worked their magic differently from the way Oscar Barnak might have done it back in 1925, that's your perogative.

 

[AyeYo]

What's wrong with this workflow? Tip....if you don't know the answer just ask any photographer

Take photograph using 20 mp sensor - shoot raw as this allows non destructive editing

Perform a series of 'destructive' edits which culminates in cropping the image to approximately 15mp

Resize image to 20mp

Start on your process of 'non destructive' edits in Adobe Camera Raw

Bingo.

But the real issue, as it was the other over 9000 times this has been brought up, is in photogrammetry. Complex picture stitching is a disaster with the P4P because of this issue.

If DJI couldn't make a lense that gives a usable 20MP, then don't call it 20MP.

 

[DaRana]

Bingo.

But the real issue, as it was the other over 9000 times this has been brought up, is in photogrammetry. Complex picture stitching is a disaster with the P4P because of this issue.

If DJI couldn't make a lense that gives a usable 20MP, then don't call it 20MP.

Workflow wise it does add some overhead. I do a lot of large HDR Panoramas. In order for the stitching to work effectively I import the raw files into LR, apply my own brew of baseline develop presets on top of the integrated DNG profile, then export to 100% JPG. At that point PtGui et al will happily stitch and I just nuke the jpgs after I have an .exr

I've been a bit unhappy with corner softness as well, not sure how much of it is due to the barrel distortion correction vs general sensor/lens quality. The result though is a pretty significant difference between center vs edge sharpness. It actually just occurred to me that I think my next hdr pano session I may try an even larger overshoot than normal then cropping in to nuke those soft corners.

I've tried shooting in-camera JPG to avoid the process and export step, which takes a lot of time, but haven't been happy with the results. Plus the margin for error is so slim since in part because we have so little control over the bracket sizes (key for the hdr part) and nailing color temp from hundreds of feet away during the rapidly shifting light of a sunset or incoming storm is not always ideal.

All that said, I continue to be in awe of the quality of this sensor + lens combo. It compares quite well to my 5D3 + L glass in many situations - on the ground I would take the 5d every time but the gap is impressive. And blows the Mavic out of the water for both stills and video.

 

[ryanmanchester]

I haven't seen anyone demonstrating how this terrible flaw affects their photography and how they are unable to get the shots they want because of it.

Its false advertising, at best misleading simple as that. My p4p pictures are good but it's still misleading regardless of which way the camera works.