Viofo A119S with F1.2 lens

[dirkzelf]

You know I can't help myself, so, here it is, focused and ready to go....

Soon in this theater..... Stay tuned!

 

[Lola]

You know I can't help myself, so, here it is, focused and ready to go....

Soon in this theater..... Stay tuned!

View attachment 39632

This should be very interesting.

 

[dirkzelf]

Problem... Nightfall is LATE..... but don't worry, video's will arrive soon...

 

[dirkzelf]

OK, yesterday evening I was waiting for it to get dark, but guess what, close to midnight there was still some remaining light from the sun gone under, nevertheless I took it, because I didn't want to wait any longer..... so here it is, let me know what you think.

Notice the events on +/- 1:20 into the video, where the low beam goes off, and only the smallest parking lights were on, and where I saw close to nothing with the naked eye....

 

[dirkzelf]

Comparison to some earlier recording with

Viofo A119S and standard lens



Viofo A119S and F1.2 lens

 

[Moon]

Given the different language ... I couldn't see any of the lettering on the signs in the above night video unless it was right up close.
How does it go reading number plates at night? In this video there weren't any ... and that is the main purpose ... top priority.

Is VIOFO releasing a Cam with the 1.2 lens or have you custom fitted one?

 

[dirkzelf]

Given the different language ... I couldn't see any of the lettering on the signs in the above night video unless it was right up close.
How does it go reading number plates at night? In this video there weren't any ... and that is the main purpose ... top priority.

Is VIOFO releasing a Cam with the 1.2 lens or have you custom fitted one?

You probably haven't seen the whole video, and I don't blame you for that, since it's quite a long one, but I have seen plenty of license plates:


Police thinks "what's he doing up so late, shall we pull him over...? Nah... he drives a Fiat, can't be a bad guy this one"



For all dashcams (as far as I know) goes: reading numberplates in the night hours only works for cars right upfront, prefferrably at standstill, moving objects always blurr. It's like buying a magnifier glass in the dollar store, and expect to examine the moon's surface from earth.

However, that wasn't the reason for this test since I know this after a year or 5 of testing.

The reason was to compare it with the original lens, and the screenshots above show clearly a brighter and sharper image than with the original lens in the night time.

I have no idea what VIOFO will do about that, it's just a lens I bought of Ali's Express, and it turned to be very successfull in the Mobius 1 and JooVuu X dashcams, so I thought to give it a go in this A119S.

Daytime results somewhere later this week.

 

[Nigel]

Given the different language ... I couldn't see any of the lettering on the signs in the above night video unless it was right up close.
How does it go reading number plates at night? In this video there weren't any ... and that is the main purpose ... top priority.

Is VIOFO releasing a Cam with the 1.2 lens or have you custom fitted one?

I think in these midnight images, it is so dark that both lenses are using maximum exposure time, so there is the same amount of motion blur, the only difference is that the F1.2 lens can see deeper into the shadows and the slightly brighter areas are clearer because the darkest areas always lack detail.

In brighter conditions, once the camera gets away from maximum exposure time, there will always be less motion blur with the F1.2 lens, however in daylight F1.2 lenses normally struggle with sharpness and focus, which is why Viofo doesn't use one as standard. It will be interesting to see the daylight results...

 

[dirkzelf]

I think in these midnight images, it is so dark that both lenses are using maximum exposure time, so there is the same amount of motion blur, the only difference is that the F1.2 lens can see deeper into the shadows and the slightly brighter areas are clearer because the darkest areas always lack detail.

In brighter conditions, once the camera gets away from maximum exposure time, there will always be less motion blur with the F1.2 lens, however in daylight F1.2 lenses normally struggle with sharpness and focus, which is why Viofo doesn't use one as standard. It will be interesting to see the daylight results...

Yeah, what he said!

 

[Dashmellow]

F1.2 lenses don't "struggle with sharpness and focus". These fast M12 all use aspheric elements and they tend to be be well designed and have good resolving power. The real issue with M12 "Starlight" lenses is that they struggle with a very short depth of field which can make the optimal hyperfocal distance a challenge to determine and are often a compromise when used in dash cams. These are CCTV lenses designed to be used on static fixed mount cameras viewing static scenes rather than the dynamic, ever changing environment dash cams operate in where both camera and subject are moving while trying to capture subjects at various distances from the camera.

 

[Dashmellow]

@dirkzelf, did swapping lenses in the Viofo require a complete tear-down of the camera and lens module?

 

[Nigel]

F1.2 lenses don't "struggle with sharpness and focus". These fast M12 all use aspheric elements and they tend to be be well designed and have good resolving power. The real issue with M12 "Starlight" lenses is that they struggle with a very short depth of field which can make the optimal hyperfocal distance a challenge to determine and are often a compromise when used in dash cams. These are CCTV lenses designed to be used on static fixed mount cameras viewing static scenes rather than the dynamic, ever changing environment dash cams operate in where both camera and subject are moving while trying to capture subjects at various distances from the camera.

"they struggle with a very short depth of field" = focus issues when used in a fixed focus camera that is exposed to a huge temperature range.

Having an aspheric element doesn't automatically make the lens perfect! There are still good ones and bad ones.

 

[Dashmellow]

"they struggle with a very short depth of field" = focus issues when used in a fixed focus camera that is exposed to a huge temperature range.

Having an aspheric element doesn't automatically make the lens perfect! There are still good ones and bad ones.

"Having an aspheric element doesn't automatically make the lens perfect! There are still good ones and bad ones." - True, but these ƒ/1.2 Starlight lenses from Treeye are excellent for the money.

The temperature range is completely unrelated to the focusing challenges those of us who have actual experience with these aftermarket lenses are talking about. As mentioned, these lenses yield very short depth of field.

 

[dirkzelf]

@dirkzelf, did swapping lenses in the Viofo require a complete tear-down of the camera and lens module?

Yes, I looked up how to on the good old Utube, the only thing is to fix the lens at focus. I use a lens fixing ring, but it's a little tricky since the whole construction of the lens Swivel mount doesn't allow easy access to the barrel and fixing ring. But be patiënt. You will figure it out.

 

[Dashmellow]

Yes, I looked up how to on the good old Utube, the only thing is to fix the lens at focus. I use a lens fixing ring, but it's a little tricky since the whole construction of the lens Swivel mount doesn't allow easy access to the barrel and fixing ring. But be patiënt. You will figure it out.

Thanks! Did you use the AV out port into a monitor or HDTV to focus? The reason I'm asking about this is that I came into possession of a Viofo A119 some time ago and when I finally got around to checking it out, the focus was slightly off. I see that there is a good tutorial on this on YouTube. One of my main concerns was dealing with the lens housing ratchet spring, but it looks pretty easy. One time I opened up an old camera with a similar design and the spring shot off somewhere never to be seen again.

 

[dirkzelf]

Thanks! Did you use the AV out port into a monitor or HDTV to focus? The reason I'm asking about this is that I came into possession of a Viofo A119 some time ago and when I finally got around to checking it out, the focus was slightly off. I see that there is a good tutorial on this on YouTube. One of my main concerns was dealing with the lens housing ratchet spring, but it looks pretty easy. One time I opened up an old camera with a similar design and the spring shot off somewhere never to be seen again.

Yeah you gotta be careful with the Swivel ratched spring thingie, it's a little unsettling when it proves to not go back in place so easily.... Hahaha BTW I just used the display I ALREADY have ON the camera, THAT was the easy part....

 

[dirkzelf]

The tricky thing is that the out er lens protector slides OVER the original lens AFTER focusing. With th F1.2 lens that won't fit, SO.... you need to fix the focus with the outer part ALREADY mounted....

 

[kamkar]

Hehe yeah this time of the year at night its easy to see where north are, if you have a clear view of the horizon.

Just pisses me off we now have a nation wide ban on any form of fire and grilling, i was planning for a nice chillout ( grill ) and scale offroading trip to the forest.
Then again at night there are not many other people in the forest, maybe a law or 2 will get circumvented though it is a 5000 Dkkr fine, they will have to find us first.

 

[dirkzelf]

Hehe yeah this time of the year at night its easy to see where north are, if you have a clear view of the horizon.

Just pisses me off we now have a nation wide ban on any form of fire and grilling, i was planning for a nice chillout ( grill ) and scale offroading trip to the forest.
Then again at night there are not many other people in the forest, maybe a law or 2 will get circumvented though it is a 5000 Dkkr fine, they will have to find us first.

Dry weather éh.... Yeah here too. Across half the country I could smell forrest fires through out the whole truck ride... Kinda unsettling, really not nice, considering I had my truck cought fire last week, the area where left front lights are cought fire, perhaps shortcut or heat, but we still don't know why or what happened. That was NOT a nice day, I can tell you that.

Luckily we could extinguish rapidly, but if you get paniced and don't act fast we could have lost it complete. I didn't mention it to the girls at home, for obvious reasons.... Just love them too much to upset them....

 

[dirkzelf]

OK here's the daytime sample 1080p/60, but blocky as h@ll, so further down I've got you a 4k upscaled version upload, but to be honest it's not significantly better, but yt didn't save it as a 4K clip, just 1080p, while the original uploaded file really is a 4K one.....

Should have cleaned the windshield.... sorry.

Maybe the lens is set TOO sharp? Anyone?