Dashmellow
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It's been taking longer than I anticipated thanks in part to the harsh winter weather and some other priorities but I've been testing out the new Mobius A2 lens for the last two months using a camera that ships with the A2 module installed which was graciously provided to me by the developer.
Firstly, the new A2 lens is a superb optic that is extremely well corrected. While it is the narrowest FOV lens offered by Mobius it is still a "wide angle" and as such it provides an image that has only the most minimal level of barrel distortion. What little distortion exists is negligible and can essentially be ignored, assuming you even notice it in the first place. There is virtually no lens flare to speak of, even in the most challenging lighting. There is no noticeable color fringing. There is little evidence of field curvature as the lens is quite sharp edge to edge. The lens has good contrast, resolution and resolving power.
All in all the lens is highly capable and the camera generally performs beautifully even in some challenging environments. It's a late generation Mobius 1 v.3, after all.
That said, there have been some highly unexpected and unusual problems regarding white balance corrections and color shifts.
During the early "Phase 1" Mobius firmware development there was a widely known issue with AWB stabilization where the camera would suddenly experience significant color shifts when the camera became overwhelmed by a specific RGB color entering the FOV when the amount of that color would reach a threshold level where it would trigger a shift to its opposite RGB color value on a typical RGB color wheel.
So, a large RED vehicle would trigger a CYAN/BLUE color cast or a large BLUE vehicle like a truck would trigger a YELLOW cast and a YELLOW vehicle might trigger a BLUE shift.
This color balance stabilization issue was "cured" during several early Phase one firmware iterations and was fully resolved by the time firmware v.59 was released.
For some odd reason this problem has reappeared in the A2 camera unit that was provided to me and at this point in time it is not clear what the cause is. The developer is evaluating sample clips I have provided and as yet there is no definitive explanation. Stay tuned.
In the meantime, my personal theory is that this may be more related to the sensor in the new A2 module than the lens itself but it is possible that the firmware needs to be tweaked to accommodate the specific characteristics of the new optic. It is unclear if there have been any specific changes to the sensor in the module on the new A2. Maybe there is even a one-off defect?
I do recall when I put a "B" lens into an original "C" module nearly two years ago, the color balance was off (blueish bias). The fix-it was to re-set the camera for the "B" lens using mSetup rather than the "C" setting the module had been set to previously when it had the "C" optic installed. The various specific lens setting options on the Mobius are all tuned to the color characteristics of each lens and Mobius may in turn have to provide an "A2" setting specific to that lens in the mSetup GUI.
Still, this does not explain the abrupt color shifts. A general color cast is one thing but shifting with changes in the scene colors is another matter altogether.
Finally, the other issue I have noticed is that it is not uncommon for certain challenging lighting conditions to cause the camera to produce unusually dark images. This often happens if the camera confronts a situation with a bright sky against an otherwise flatly lit scene. On a few occasions, a dark overcast day seems to make for darker underexposed images. This may be due to the smaller apparent aperture on the A2 lens but I am as yet not privy to what the aperture number is on the A2. (I'm working on that. )
*************************************************************************
So, I mounted both an original Mobius camera (v.1 pcb with original first generation A lens module) and the new v.3 Mobius A2 lens camera side by side touching each other on a small wooden board. This way both cameras have an exactly synchronized FOV for comparison.
Both cameras are set to the identical default settings at the highest bit rate with WDR-ON.
Here are some recent screen shots to peruse. (shot in my "backyard" - looking 100 miles North/Northeast from Southern Vermont USA towards the lower White Mountains in New Hampshire and up the Connecticut River Valley towards Mount Ascutney in Vermont.)
The first thing to notice is that the new A2 lens is slightly longer in focal length and therefore has a slightly narrower FOV with greater magnification.
The second thing you will observe is that the new A2 lens has a distinctly blueish color cast (at least on snow).
The third thing to notice is that the A2 lens has excellent contrast characteristics compared to the original A lens. (which is not bad itself.)
Original Mobius A lens
New Mobius A2 lens
Here I've demarcated the differences between the FOV coverage of the two lenses.
*************************************************************
Color Shifting
There is an issue with RED/CYAN,BLUE color shifts which can happen quite often during a days driving around with the A2 lens camera. There was no evidence of any BLUE/YELLOW shifting.
Here are two short YouTube clips shot on different days in the same location. I wish I could have provided longer clips but with my abysmal bandwidth out here in the middle of nowhere it's the best I can do as each one minute or so clip takes 30-40 minutes to upload.
For anyone interested, here are the raw clips of the above videos uploaded to MEGA.NZ
https://mega.nz/#!YwdiRLgI!LQnrYU3_GPrDkkhxyM3LIGwhntsQZMrC90Azw2Q8IGM
https://mega.nz/#!U89SVL5L!NrikOWBAW5CpUypjc-64d10R-Rj9Mq9RcksCVkSbDD4
Finally, here are several examples of the A2 camera going dark in settings where it really shouldn't. Usually, there is an exaggerated response to a bright sky, even if it is only a small percentage of the FOV but this is not always the case. In all of these shots the ambient lighting was much brighter than the images captured.
Firstly, the new A2 lens is a superb optic that is extremely well corrected. While it is the narrowest FOV lens offered by Mobius it is still a "wide angle" and as such it provides an image that has only the most minimal level of barrel distortion. What little distortion exists is negligible and can essentially be ignored, assuming you even notice it in the first place. There is virtually no lens flare to speak of, even in the most challenging lighting. There is no noticeable color fringing. There is little evidence of field curvature as the lens is quite sharp edge to edge. The lens has good contrast, resolution and resolving power.
All in all the lens is highly capable and the camera generally performs beautifully even in some challenging environments. It's a late generation Mobius 1 v.3, after all.
That said, there have been some highly unexpected and unusual problems regarding white balance corrections and color shifts.
During the early "Phase 1" Mobius firmware development there was a widely known issue with AWB stabilization where the camera would suddenly experience significant color shifts when the camera became overwhelmed by a specific RGB color entering the FOV when the amount of that color would reach a threshold level where it would trigger a shift to its opposite RGB color value on a typical RGB color wheel.
So, a large RED vehicle would trigger a CYAN/BLUE color cast or a large BLUE vehicle like a truck would trigger a YELLOW cast and a YELLOW vehicle might trigger a BLUE shift.
This color balance stabilization issue was "cured" during several early Phase one firmware iterations and was fully resolved by the time firmware v.59 was released.
For some odd reason this problem has reappeared in the A2 camera unit that was provided to me and at this point in time it is not clear what the cause is. The developer is evaluating sample clips I have provided and as yet there is no definitive explanation. Stay tuned.
In the meantime, my personal theory is that this may be more related to the sensor in the new A2 module than the lens itself but it is possible that the firmware needs to be tweaked to accommodate the specific characteristics of the new optic. It is unclear if there have been any specific changes to the sensor in the module on the new A2. Maybe there is even a one-off defect?
I do recall when I put a "B" lens into an original "C" module nearly two years ago, the color balance was off (blueish bias). The fix-it was to re-set the camera for the "B" lens using mSetup rather than the "C" setting the module had been set to previously when it had the "C" optic installed. The various specific lens setting options on the Mobius are all tuned to the color characteristics of each lens and Mobius may in turn have to provide an "A2" setting specific to that lens in the mSetup GUI.
Still, this does not explain the abrupt color shifts. A general color cast is one thing but shifting with changes in the scene colors is another matter altogether.
Finally, the other issue I have noticed is that it is not uncommon for certain challenging lighting conditions to cause the camera to produce unusually dark images. This often happens if the camera confronts a situation with a bright sky against an otherwise flatly lit scene. On a few occasions, a dark overcast day seems to make for darker underexposed images. This may be due to the smaller apparent aperture on the A2 lens but I am as yet not privy to what the aperture number is on the A2. (I'm working on that. )
*************************************************************************
So, I mounted both an original Mobius camera (v.1 pcb with original first generation A lens module) and the new v.3 Mobius A2 lens camera side by side touching each other on a small wooden board. This way both cameras have an exactly synchronized FOV for comparison.
Both cameras are set to the identical default settings at the highest bit rate with WDR-ON.
Here are some recent screen shots to peruse. (shot in my "backyard" - looking 100 miles North/Northeast from Southern Vermont USA towards the lower White Mountains in New Hampshire and up the Connecticut River Valley towards Mount Ascutney in Vermont.)
The first thing to notice is that the new A2 lens is slightly longer in focal length and therefore has a slightly narrower FOV with greater magnification.
The second thing you will observe is that the new A2 lens has a distinctly blueish color cast (at least on snow).
The third thing to notice is that the A2 lens has excellent contrast characteristics compared to the original A lens. (which is not bad itself.)
Original Mobius A lens
New Mobius A2 lens
Here I've demarcated the differences between the FOV coverage of the two lenses.
*************************************************************
Color Shifting
There is an issue with RED/CYAN,BLUE color shifts which can happen quite often during a days driving around with the A2 lens camera. There was no evidence of any BLUE/YELLOW shifting.
Here are two short YouTube clips shot on different days in the same location. I wish I could have provided longer clips but with my abysmal bandwidth out here in the middle of nowhere it's the best I can do as each one minute or so clip takes 30-40 minutes to upload.
For anyone interested, here are the raw clips of the above videos uploaded to MEGA.NZ
https://mega.nz/#!YwdiRLgI!LQnrYU3_GPrDkkhxyM3LIGwhntsQZMrC90Azw2Q8IGM
https://mega.nz/#!U89SVL5L!NrikOWBAW5CpUypjc-64d10R-Rj9Mq9RcksCVkSbDD4
Finally, here are several examples of the A2 camera going dark in settings where it really shouldn't. Usually, there is an exaggerated response to a bright sky, even if it is only a small percentage of the FOV but this is not always the case. In all of these shots the ambient lighting was much brighter than the images captured.
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