Original Mobius night recording with 4mm ~ F1.2 lens (!)

[dirkzelf]

I don't use AmpCap so I wouldn't know but it is unlikely to be adjusting the camera in any way. The AmpCap app is probably just changing the values you see on your screen. The only way to adjust the color on your Mobius is via mSetup which is adjusting the values within the camera via the firmware.

Yeah I figured.

 

[dirkzelf]

OK, I took the lot out at work today again, and I want to show you some screenshots for some interesting brightness comparison, and more comparisons on license plate readability.....

MOBIUS A2 LENS:


MOBIUS F1.2 LENS


VIOFO A119S


MOBIUS A2 (full beam)


MOBIUS F1.2 (full beam)


VIOFO A119S (full beam)


MOBIUS A2 (@80kph both ways)


MOBIUS F1.2 (@80kph both ways)


VIOFO A119S (@80kph both ways)


At first I thought I might have focussed the F1.2 Mobius better than the A2, but when looking at the A119S, that's not sharp at all either compared to the F1.2 lens.....! So, I will of course look into that (A2 being not as sharp as the F1.2), but I fear the F1.2 outperforms both A2 and A119S.....

 

[dirkzelf]

3 more, truck parked and headlights switched off:

MOBIUS A2


MOBIUS F1.2


VIOFO A119S

 

[TonyM]

That F1.2 lens has a surprisingly large depth of field. I thought that might be one area where it does not compare so well to the A119S, but that does not seem to be the case.

 

[dirkzelf]

Yeah, i'm starting to think my A119S may be slightly out of focus, please @VIOFO_Support what do you think of it? Do I need to refocus the lens, or is this how it's supposed to be? Please join in.

 

[Nigel]

Yeah, i'm starting to think my A119S may be slightly out of focus, please @VIOFO_Support what do you think of it? Do I need to refocus the lens, or is this how it's supposed to be? Please join in.

Hard to tell since your daylight images have been resized somewhere along the line, but to me it looks like the focus could be improved a little with a very small twist of the lens. I wouldn't say it is out of focus, but it doesn't look quite perfect either.

 

[dirkzelf]

At first I thought I might have focussed the F1.2 Mobius better than the A2, but when looking at the A119S, that's not sharp at all either compared to the F1.2 lens.....! So, I will of course look into that (A2 being not as sharp as the F1.2), but I fear the F1.2 outperforms both A2 and A119S.....

So, I've checked the focus on the A2 lens Mobius and the F1.2 on static objects, and the sharpnes is the same.

A2 (from +/- 2.5 meters):


F1.2 (from +/- 2.5 meters)


(yes it's a mess, I know, but we're in a building renovation process...... sigh ... )

Which leads me to conclude that the higher (faster?) throughput of light in this lens leads to sharper images of moving objects. And the unsharpness of the license plates on upcoming moving objects recorded with the standard A2 lens (even in bright sunlight!) is due to motion blurr, that's actually very sad, and contrary of what I always thought....

So I've been checking earlier footage of my Mobius with the C2 lens, and that doesn't really show readable license plates of upcoming traffic (@80kph) either, so I'd have to restate me earlier saying somewhere that it records readable license plates in that particular condition (bright sunlight / upcoming 80kph traffic) ..... sorry.

 

[dirkzelf]

That F1.2 lens has a surprisingly large depth of field

Well, it is a long lens....

 

[dirkzelf]

Hard to tell since your daylight images have been resized somewhere along the line, but to me it looks like the focus could be improved a little with a very small twist of the lens. I wouldn't say it is out of focus, but it doesn't look quite perfect either.

I just resized all 3 to 50% since the original was too large to upload. So I recon that doesn't influence the overal comparison.

(+ Added 2 screenshots 2 posts earlier to compare focus/sharpness on steady objects A2/F1.2)

 

[TonyM]

So, I've checked the focus on the A2 lens Mobius and the F1.2 on static objects, and the sharpnes is the same.

A2 (from +/- 2.5 meters):
View attachment 33848

F1.2 (from +/- 2.5 meters)
View attachment 33847

Your A2 has dust spots on the sensor

 

[Nigel]

I just resized all 3 to 50% since the original was too large to upload. So I recon that doesn't influence the overal comparison.

(+ Added 2 screenshots 2 posts earlier to compare focus/sharpness on steady objects A2/F1.2)

Looking at the previous images, it is noticeable that the F1.2 is over-exposed relative the A2. I don't know why, but you could set maybe two stops of -EV so that they are exposed the same, then you should see that there is significantly less motion blur on the F1.2 images. You could also set the A119S with one stop of -EV to even the exposures on the daytime image, it already has the least motion blur and that would give it even less.

 

[Dashmellow]

Looking at the previous images, it is noticeable that the F1.2 is over-exposed relative the A2. I don't know why, but you could set maybe two stops of -EV so that they are exposed the same, then you should see that there is significantly less motion blur on the F1.2 images. You could also set the A119S with one stop of -EV to even the exposures on the daytime image, it already has the least motion blur and that would give it even less.

Personally, I don't see the dramatic sort of over-exposure you claim for the ƒ1.2 lens; certainly not anywhere in the range of two "stops" EV. If anything the A2 seems very slightly underexposed. Either way, the Mobius doesn't employ the usually heavy handed, course "EV" settings seen on most dash or action cams but rather 128 steps of adjustment (plus or minus) which provides for much more subtle and refined image tuning.

 

[TonyM]

Personally, I don't see the dramatic sort of over-exposure you claim for the ƒ1.2 lens; certainly not anywhere in the range of two "stops" EV. If anything the A2 seems very slightly underexposed. Either way, the Mobius doesn't employ the usually heavy handed, course "EV" settings seen on most dash or action cams but rather 128 steps of adjustment (plus or minus) which provides for much more subtle and refined image tuning.

In your prior testing, have you determined what the +/-128 range relates to in EV stops? It's something I've been meaning to do, but never made the time.

 

[dirkzelf]

Your A2 has dust spots on the sensor

yah I know....

 

[dirkzelf]

Looking at the previous images, it is noticeable that the F1.2 is over-exposed relative the A2. I don't know why, but you could set maybe two stops of -EV so that they are exposed the same, then you should see that there is significantly less motion blur on the F1.2 images. You could also set the A119S with one stop of -EV to even the exposures on the daytime image, it already has the least motion blur and that would give it even less.

I gave the F1.2 -/- 10 EV, should I step further down to -/- 20 EV?

As to the A119S, you say it has the LEAST motion blurr?? Then why is the license plate unreadable and the F1.2 gives a clear readable license plate? I'm affraid I don't understand what you mean, sorry, if you can, please clarify some more.

 

[Dashmellow]

In your prior testing, have you determined what the +/-128 range relates to in EV stops? It's something I've been meaning to do, but never made the time.

I'm not sure Exposure Value stops equate exactly with how Mobius handles exposure adjustment increments but of course, there would be a relationship. I guess I've never had much reason to think about it. Mobius approaches their imaging settings based on the 8 bits of information the DSP provides with 1-256 levels of adjustment per pixel. I usually just make any required adjustment as a percentage of the range that is possible and increase or decrease accordingly.

 

[dirkzelf]

In your prior testing, have you determined what the +/-128 range relates to in EV stops? It's something I've been meaning to do, but never made the time.

I haven't, and not going to, I guess it's just a different way of measuring, like miles or kilometers in distance matters....

 

[dirkzelf]

Personally, I don't see the dramatic sort of over-exposure you claim for the ƒ1.2 lens; certainly not anywhere in the range of two "stops" EV. If anything the A2 seems very slightly underexposed. Either way, the Mobius doesn't employ the usually heavy handed, course "EV" settings seen on most dash or action cams but rather 128 steps of adjustment (plus or minus) which provides for much more subtle and refined image tuning.

in the in-home static comparison screenshots (TT-HT-66 license plate) I set both cams to

SHARPNESS +20
CONTRAST +20
SATURATION +20

And A2 EV to 0, and F1.2 to -10.

Im going to set F1.2 lens cam to -/-20 EV tomorrow.

I'm not sure yet about what I shoul do in the A119S settings to get better daytime license plate reading. Maybe set to 30fps, and lower the EV a little?

Any thoughts?

 

[Dashmellow]

I haven't, and not going to, I guess it's just a different way of measuring, like miles or kilometers in distance matters....

The Mobius has 8 bits of info to work with. 8-bit refers to the amount of colors capable of being displayed, or shades of gray from pure white to pure black, or exposure, saturation, etc. For example, 8-bit is the same as 256 colors. So the Mobius GUI provides 128 levels of plus adjustment and 128 levels of minus adjustment. (128 x 2 = 256)

 

[Dashmellow]

in the in-home static comparison screenshots (TT-HT-66 license plate) I set both cams to

SHARPNESS +20
CONTRAST +20
SATURATION +20

And A2 EV to 0, and F1.2 to -10.

Im going to set F1.2 lens cam to -/-20 EV tomorrow.

I'm not sure yet about what I shoul do in the A119S settings to get better daytime license plate reading. Maybe set to 30fps, and lower the EV a little?

Any thoughts?

Not owning an A119S it's hard to make a recommendation. As I mentioned the other day, the best thing to do is try a new setting or settings and see what happens.