Meta4
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Still photo curved horizon, video straight..
- Thread starter Håkan22
- Start date
Yep, I've read it and left well alone. I see what they are doing but fail to understand how one generic fudge to replace another generic fudge is in any way an improvement
For stuff that isn't critical (95% of what I do) then I work within the constraints applied by DJI/Adobe. For the other 5% I use a different piece of software to achieve the results I need.
Unlike some members of the forum, I don't feel the need to post on threads that don't seem that important to me
Yep, I've read it and left well alone. I see what they are doing but fail to understand how one generic fudge to replace another generic fudge is in any way an improvement
For stuff that isn't critical (95% of what I do) then I work within the constraints applied by DJI/Adobe. For the other 5% I use a different piece of software to achieve the results I need.
Unlike some members of the forum, I don't feel the need to post on threads that don't seem that important to me
Don't bother anyway, as it's a mix of contradictions. He calls the upscaling on the images a "myth" and then proceeds to talk about how some pixels are upscaled others downscaled and in one case even talks about being left with a 13mp image to work with.
His sample images display that original pixel data has indeed been discarded. So the "myth" is no myth at all, as DJI presents theses images at the full 20mp size.
That's pretty much how I read the thread. I'm still not sure what he was trying to achieve
Well... I was just tinkering for my own curiosity along with planning the best possible quality workflow for me. There are no contradictions as such once you make sense of it all. Well one contradiction so far was that I too at first thought it was corrected and then up-scaled by DJI until I dug deeper and found it wasn't, hence the myth.
For what is is worth consider the image above. Same raw shot processed 4 different ways. This is just the center crop at 100%.
1. Is the original uncorrected raw (not using the embedded DJI profile). It shows up the extreme barrel distortion (almost like a P2V+) and vignetting (severe almost black right in corners) from the less than adequate lens vs sensor size. It is what it is and here's hoping the P5 will use a larger and better lens construction. It is 20mp off the sensor and as raw as it comes.
2. Is DJI's embedded profile. It corrects the bad stuff. While we do not know exactly how they are processing the lens correction, it is most likely similar to #3 using a lens profile. This process stretches the outer edges and more still into the corners but not in the center for the most part.The size of the chair does not change much at all vs #1 and the field of view is consistent with the amount of stretching applied as per #3.
3. Is my custom lens profile for LR. It corrects the bad stuff too but uses a little bit less stretching than DJI's embedded profile. Notice the chair is smaller meaning while the outer edges/corners are stretched almost as much as DJI's a second layer of adjustment also pushes in the center bubble. So both up-scaling by means of stretching outer edges and down-scaling by means of pushing in the center bubble. A slight FOV gain can be had by using this method.
4. Is taking the uncorrected raw #1 and using LR's manual distortion correction with a value of 100 (max) (107 is required actually but near enough for the eye). This tool works differently and does not stretch out anything. Instead it pushes in the middle of all 4 sides. You then have to crop off the missing detail/bowed edges. The end result is all down-scaling and about a 13mp image. It is the sharpest method overall if only going to downsize again for web viewing below 13mp. It also has a fair bit more FOV than any other method. It is highly unlikely that DJI use this method as a) its more processor intensive (correct + crop + upscale back to 20mp vs just correct in one step) and b) if using this method the FOV should be greater than it is in #2 or #3.
Does any of this matter. Not really to most... still the best image from a Phantom to date and various ways to develop a raw if desired.
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But the underlying fact is that a large portion of the original sensor data is discarded, so the final image when presented at a 20mp size is interpolated no matter which way you look at it.... and this, while it does not matter to some, does matter to others.
No denying the barrel distortion is huge and yes I do not like it either. Yes I feel a bit cheated by the DJI marketing is this respect. Considering the P3 and sounds like P4 with smaller sensors have lenses that match better and do not have such bad barrel distortion - yet they put a nice larger sensor in these top end models and then cut corners with a reasonable lens to match. I wish the lens performed like my 24mm DSLR one (which only discards a fraction when correcting the minimal distortion). But it is what it is so I like you and everyone else either deal with it (after having a whinge) or sell it and hope for a miracle in the P5 lens. All lens correction profiles need to interpolate or stretch to some degree just unfortunately the P4P needs a lot which makes for really soft edges.
If we want less to be discarded and/or interpolated up use method #4 (some images get away with less than 100 which gets closer to original FOV). If you want the middle road use #3. If you want less work and/or do not see any problems use method #2 right out of camera. If you want perfection buy a $2000 DSLR lens + a $5000 camera body + a $10,000 jib + a $60,000 truck to move it all around in order to get 20m high shots
Ok, messing around now as I wish my $2000 got me all that in the P4P too but alas.I'd simply be happy to have the use of what they sold me.... a "20mp sensor". I can bypass the embedded profile and make my own corrections, but I can't avoid having to dump the unexposed or shitty areas that the sensor captures by seeing the edge of the image circle. This is not what they advertised or what I paid good money for and the arguments that have been chucked around in this site ie "it's the best there is" "sell it & buy something else" "it's built to a price point" etc are all mute. DJI flat out misrepresents the camera.
Yes, we have to deal with it, but that doesn't mean that they shouldn't be held accountable by those who are effected.
Yes, we have to deal with it, but that doesn't mean that they shouldn't be held accountable by those who are effected.
Well I made my choice. In my country we are protected from false or misleading advertising and IMO I would have been able to obtain a refund if I decided to based on this matter and one other. I decided I wanted to keep using it as is, warts and all instead. Not sure what else one can reasonably expect other than a refund. It's not like one can expect a new improved P5 after keeping and continuing to use the old one they were disgruntled with.
I'm fully aware of the consumer law in Aus but the sad part is that DJI claim that their specs and advertising are legit, because it does have a 20mp sensor. The fact it's unusable is ignored by them and when photo evidence is provided they go to ground and cease all contact. So to enforce my right as a consumer, I need to entertain a protracted battle between myself, the store and DJI and if that goes nowhere (which it has at this point) then it starts all over again trying to get the consumer departments involved. It really is easier to sell and move, or work with it how it is.... but again, that doesn't diminish that fact that the P4P camera is not what they make it out to be and that DJI is full of $hit. lol
Meta4
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Rusty .. how about moving on? You've been singing the same song for a long time now.
If the P4 pro isn't good enough for you, get something that is.
fyi ... If this guy is right, it seems that the Sony RX100 does the same thing: Phantom 4 Pro camera is really 4K?
While the amount of curvilinear distortion on the Sony is still saddening, at least it has a lens that projects an image that adequately covers the sensor and leaves the photographer with the option of using all 20mp.
