Any way to reduce the contrast?

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murcod

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South Australia
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Dash Cam
Mobius, A119v2, A119v3
Has anyone else found the contrast ratio is way too high in the A119V3? Detail in shadows is lost; I'd much prefer less contrast with more shadow detail than footage that appears impressive for it's high contrast ratio.

Has there been any 3rd party software developed? I notice @BCHobbyist has done quite a bit of work with other Viofo models.
 
Would the EV level help ?

Left mine on zero with WDR off and it seems fine.
 
I've got the EV set to +1/3 -> below is an example of what I'm talking about. If the contrast was reduced there would be more detail shown of the person driving the vehicle.

(Rear facing camera, no CPL, through factory tinted glass, latest firmware.)

Contrast too high.jpg
 
Notice the sky is blown out (over exposed) but then all the bushes by the side of the road are virtually black, so is under the car and the car's interior (through an open window) is very dark too.

I've found similar issues with home security cameras. The contrast may look great (if you're making a movie) but for security purposes lowering the contrast helps bring out the detail in the shadows.
 
murcod said:
I've got the EV set to +1/3 -> below is an example of what I'm talking about. If the contrast was reduced there would be more detail shown of the person driving the vehicle.

(Rear facing camera, no CPL, through factory tinted glass, latest firmware.)

View attachment 49731
Click to expand...
Tinted windows tend to affect the exposure balance and very hard to get it right even if you increase the EV values.
I used to have two a119s on my SUV, one in front and the other in the rear window. The rear window is factory tinted (as most of them) but not sure at what percentage but enough to mage a very noticeable difference in the light contrast. I tried to increase the EV to compensate for the darkness but it gets the sky overexposed ands the shadows still won’t look quite the same as the front camera does. The front camera did quite well.
I feel like it would be too much to ask viofo to generate and add to the menu a selectable secondary IQ profile specifically for the use on cameras installed behind tinted glass. Don’t know if that is even possible...
 
EGS said:
Tinted windows tend to affect the exposure balance and very hard to get it right even if you increase the EV values.
I feel like it would be too much to ask viofo to generate and add to the menu a selectable secondary IQ profile specifically for the use on cameras installed behind tinted glass. Don’t know if that is even possible...
Click to expand...

I'd imagine the lighting effect with a tinted window would be very similar to using their CPL?

You can see some of the contrast issues in the below Youtube video - compare the A129 to the A119V3 at around the 25 second mark

 
In this video both Viofo models show much higher contrast (dark shadows with no detail) compared to the other two cameras.

 
I think your tint may be increasing the contrast. If you have a CPL then that can as well, maybe try without.
The WDR setting should brighten the dark areas, not everyone likes the result but it's worth a try, often better than using EV because that brightens everything, the WDR only brightens the dark areas.

Also, note that there is detail in the dark areas of your image, your problem might be more with your monitor settings, if I brighten your image in an editor by increasing gamma then I get this, how effective this is depends on your monitor so I don't know if this will look better to you or look rubbish:
1575015950260.png
Also note that if you want to see the dark detail in a video, unless you have a very bright HDR monitor, it is best to watch it at night.
 
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@Nigel I got a similar result earlier using Capture One photo software on a screen print from Windows Media Player. I used shadow and highlight adjustment to reduce the overall contrast. The main facial features were still a blob like your picture. IIRC there are some media players that let you adjust the gamma "on the fly". But should you need to do that?

I still think the camera's video output could be better/ improved in that area. I've compared some video stills from a Mobius that was in that position and it seemed to show more detail in the shadows. Those YouTube videos above also show a lack of shadow detail compared to the other cameras.
 
murcod said:
I'd imagine the lighting effect with a tinted window would be very similar to using their CPL?

You can see some of the contrast issues in the below Youtube video - compare the A129 to the A119V3 at around the 25 second mark

Click to expand...
CPL can affect the exposure but not as drastic as the tinted window as it is dark at a larger percentage. For that reason I would never add a CPL because that would only contribute to the problem. I always used a CPL on the front camera and It performed quite well at minimizing dashboard reflections without affecting the contrast that much...
 
I'll give it a go. (It's down as far as it will go without changing how it's mounted.)
 
I tried mounting it so the angle is better (angled downwards), but there's still the issue of dark areas being totally black with no detail in the shadows. I might try putting the EV level back to zero, perhaps the software is doing other undesireable things....
 
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