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Day 2 with perfect weather conditions and dramatic scenery. Shot more video with the A2S and after that with the M2P. The former in 4K Dlog mode and the latter in HLG FOV. Unfortunately I screwed up the second A2S flight that should have been in HLG mode, but forgot to press record.... go figure LOL.
So the comparisons are definitively not apples to apples. One thing I have to state here: I use Davinci Resolve Studio 17+ and I grade in HDR. It offers a built in DJI specific log profile correction. See attached DR17 setup. I use a properly calibrated 55" LG OLED E9 as my grading monitor via a DeckLink Mini Monitor 4K. I target 1000nits HDR10. DR is incredibly well equipped to do HDR even from a Rec709 10-bit log format. (this example).
Observations:
First, as discovered yesterday already, the built in White Balance measurement is WAY OFF on the A2S. Hopefully DJI will fix that soon. Meanwhile, turn on AUTO, wait a few seconds and check the reading. Then turn to manual and increase the value by 400. That will take you where you need to be.
Second, turn the drone towards an area of most brightness for your shooting sequence and with overexposure indication turned on, turn the shutter to right were most (some extreme points if not significant may still exceed exposure. Be careful of clouds especially if they are prominent) or all of the overexposure indication disappears. DO NOT USE AUTO because the exposure with change during flight and make the sequence unwatchable. It is OK to see the EV value drop into negative territory. You are OK with -1 to -3. The latter sequences may have a bit more noise but that is easy to fix.
Set to AF and touch the screen to invoke autofocus on a good contrasty object in the distance.
All this, if you plan to fly a scenic pass through some awesome terrain.
Another really important observation on the A2S. Remember, the M2P especially in FOV has a substantial barrel distortion (when recording in 10bit log) that can be fixed easily but for scenic area shots it is essentially barely noticeable so I usually leave it alone. HOWEVER the A2S has a much more annoying lens distortion which is the exact opposite of the M2P. The A2S has a pincushion distortion that when shooting landscape and panning across it, one might get a bit nauseas! That I found out from my very first video. On Davinci Resolve set the lens correction to -0.1 or thereabouts to correct the pincushion.
The M2P HLG FOV footage needed very little correction. In fact, all I did was pushing gain a little highlights and a little shadows. This mostly because I used Style=normal. Otherwise I would record with less contrast and push HDR contrast in post. Results are a bit better.
The A2S footage went through the normal flat gamma 2.4 to HDR (PQ) approximation. Partly, DR takes care of it by checking the "use 203 nits reference for Rec2100 HDR" and by pushing the shadows +50 and work "negative Lift" and "negative shadows" to restore black and shadow definition before starting HDR grading. These actions "bend" the otherwise linear gamma to be more like PQ. The fully graded results are nearly indistinguishable from corresponding HLG (HDR) footage. Turns out I prefer to start with Dlog footage especially on the A2S since it offers a little more flexibility working shadows and highlights. HDR grading only included a minor push of shadows, light, highlight and specular. It also includes dropping selective color saturation only for shadows, dark and black.
In conclusion: I attached two partial frame shots that demonstrate the difference in M2P 4K FOV definition/clarity/sharpness vs A2S 4K. They also show that the two are otherwise nearly indistinguishable short of maybe a slight tendency towards the A2S "Red" in brown and skin-tones when compared with the very natural M2P colors.
NOTE: I used Dolby Vision (part of DR studio) to view the HDR footage on SDR to take the screen shots.
I am sorry about that. I still have some reservations mainly because I am not able to control the camera as much as I would like to. After correcting the obnoxious pincushion and viewing the final result on my 65” OLED I am warming up to the A2S. Unfortunately something went wrong when I uploaded the M2P rendition of the sequence I shot for comparison. It looks fantastic here, but the YouTube version is awful. I just looked at it now. I will remove it and upload a corrected version.
Thank you very much for all your useful observations. The A2S footage is beautiful however I have noticed some stuttering when you pan or turn the camera. This is something I also have on my M2P and it ruined some of my shots. How to avoid it?
Waiting for your M2P footage to compare.
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