A139 (Pro) Telephoto Remote Camera

[viofo]

Do you think what FOV is best for telephoto, the horizontal angle less than 50°?
70° will be too wide?

 

[SafetyStealth]

Do you think what FOV is best for telephoto, the horizontal angle less than 50°?
70° will be too wide?

Do you have samples of each vs the main camera?

 

[viofo]

Do you have samples of each vs the main camera?

Maybe next month.

 

[Voldur]

This is the one I used. For that big varifocal, you will need to drill out the camera front plastic cover to get it to clear the housing.

Hey, I got the telephoto lens and got everything hooked up but for some reason I'm not getting a clear image on the interior cam with the lens. I've adjusted the lens but nothing....maybe I'm adjusting it wrong. Any idea what the problem night be?

Edit: Thought I uploaded a clip. Here it is.

 

[Dashmellow]

Hey, I got the telephoto lens and got everything hooked up but for some reason I'm not getting a clear image on the interior cam with the lens. I've adjusted the lens but nothing....maybe I'm adjusting it wrong. Any idea what the problem night be?

Edit: Thought I uploaded a clip. Here it is.

Your lens is extremely out of focus. Did you even attempt to focus the lens and just screw it in hoping for the best?

You'll need to screw the lens in or out of the barrel while viewing what the camera can see until you begin to see a clear image. Once you do that you can make finer adjustments until you achieve a sharp image.

 

[Voldur]

Your lens is extremely out of focus. Did you even attempt to focus the lens and just screw it in hoping for the best?

You'll need to screw the lens in or out of the barrel while viewing what the camera can see until you begin to see a clear image. Once you do that you can make finer adjustments until you achieve a sharp image.

I'm trying to adjust it, but now I can't get the 2nd channel to connect and record. I've reset, turned on/off and held the button to enable/disable the 2nd channel and nothing.

 

[Dashmellow]

I'm trying to adjust it, but now I can't get the 2nd channel to connect and record. I've reset, turned on/off and held the button to enable/disable the 2nd channel and nothing.

I don't happen to own an A139 Pro so I can't offer any advice about getting the second channel to connect. No doubt others here can help.

Either way you'll need to be able to find a method to focus your new lens properly.

 

[JardaB]

Telephoto fundamentally degrades the luminosity of the sensor. If the wide lens has an aperture of 1.6 then the supplemented telephoto lens has an aperture of about 5.6-8 if not worse. This is totally unsuitable for night shots. This may also be the reason the lens can't focus

 

[SafetyStealth]

Hey, I got the telephoto lens and got everything hooked up but for some reason I'm not getting a clear image on the interior cam with the lens. I've adjusted the lens but nothing....maybe I'm adjusting it wrong. Any idea what the problem night be?

Edit: Thought I uploaded a clip. Here it is.

Connect to the app to get a live view from the camera - you will need to rotate then lens to focus it, it maybe tough due to the old residual thread locker but should be possible.

Keep rotating until it is in focus at your desired distance (note the direction you rotate could be either loosening or tightening)

 

[Dashmellow]

Telephoto fundamentally degrades the luminosity of the sensor. If the wide lens has an aperture of 1.6 then the supplemented telephoto lens has an aperture of about 5.6-8 if not worse. This is totally unsuitable for night shots. This may also be the reason the lens can't focus

I don't know how you've reached such a conclusion or what logic you are using but this statement is simply not true.

DCT members have been installing telephoto lenses on dash cams for many years and there are numerous suitable wide aperture M12 lenses available. Some have fixed apertures as wide as ƒ/1.2 or even ƒ/1.0, known as "Starlight" lenses.

Here is an example from @TonyM using a 4K 12 Megapixel 8mm ƒ/2.0 lens. The focus is tack sharp and the aperture is more than adequate for excellent performance at night and this isn't even a Starvis sensor. You'll find many similar examples on the forum posted by other members, including me.

If you chose your lens wisely and install it correctly you will get good results. There is no fundamental reason that a telephoto lens would arbitrarily provide an aperture of "ƒ/5.8- ƒ/8.0 or worse" just because it is a telephoto and there is no truth to your notion that telephoto lenses can't be focused. Focus depends on the BFL and MBF specifications of the particular lens in concert with the sensor type and lens holder barrel depth.

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[Voldur]

Connect to the app to get a live view from the camera - you will need to rotate then lens to focus it, it maybe tough due to the old residual thread locker but should be possible.

Keep rotating until it is in focus at your desired distance (note the direction you rotate could be either loosening or tightening)

Gotcha.

I just now figured out I needed to unscrew the old lens from the bracket and put the telescope lens in it. I was using the washer that was included with the telephoto lens to secure it instead of the bracket. So I'm a dummy and that's on me....got all that switched out but now I can't get the 2CH to connect again.

Nothing was damaged when taking it apart, so not sure what the issue is now. Going to find another cable and give that a go. If that doesn't work then I'll get a replacement camera and retry it...I could have damaged it in some way when taking it apart again.t

 

[Dashmellow]

Gotcha.

I just now figured out I needed to unscrew the old lens from the bracket and put the telescope lens in it. I was using the washer that was included with the telephoto lens to secure it instead of the bracket. So I'm a dummy and that's on me....got all that switched out but now I can't get the 2CH to connect again.

Nothing was damaged when taking it apart, so not sure what the issue is now. Going to find another cable and give that a go. If that doesn't work then I'll get a replacement camera and retry it...I could have damaged it in some way when taking it apart again.t

The camera has a hard reset button (a hole on the left hand side of the camera you press with a bent paper clip). Press it for a few seconds with the camera powered up and see what happens. Sometimes a hard reset can fix an odd problem like you are experiencing with your second channel. If it doesn't work no harm is done. It is basically the same thing as re-booting your computer.

 

[TonyM]

I can't get the 2CH to connect again.

Nothing was damaged when taking it apart, so not sure what the issue is now. Going to find another cable and give that a go. If that doesn't work then I'll get a replacement camera and retry it...I could have damaged it in some way when taking it apart again.

The rear and internal camera connectors can be a bit temperamental. Unplug and re-plug. If you have voice notifications turned on, it should say something like "Recording, 2 channels"

 

[black9white]

hi sorry for the dumb question but i really want to try this mod. How do you open the rear camera? i dont see any screw in it to disassemble

 

[Voldur]

hi sorry for the dumb question but i really want to try this mod. How do you open the rear camera? i dont see any screw in it to disassemble

Where the power cable plugs in to is a cap. Remove the cap cover and there will be screws there. Once the screws are removed, you'll have to pry it open along the seams.

 

[black9white]

Where the power cable plugs in to is a cap. Remove the cap cover and there will be screws there. Once the screws are removed, you'll have to pry it open along the sea

Thank you! Missed the previous post explaining how to remove it..

 

[black9white]

The cover on the side of the dashcam pops off to reveal 3 screws. Really no force should be necessary, I mauled my dashcam thinking I needed force.

The lens threads into the existing thread pattern in the dashcam (after removing factory lens)

Which exact lens do you have, can you send a link? The one I ended up using fits through the factory hole in the dashcam housing which is helpful.

How did you remove the lens from the lens mount? Do i need force to remove it from the lens mount maybe using heat gun or there is an existing mount one can buy?

 

[SafetyStealth]

How did you remove the lens from the lens mount? Do i need force to remove it from the lens mount maybe using heat gun or there is an existing mount one can buy?

Rotate anti-clockwise, might need some force to break the epoxy initially, but then it should should be stiff but simple to unthread.

 

[Dashmellow]

Rotate anti-clockwise, might need some force to break the epoxy initially, but then it should should be stiff but simple to unthread.

Actually, it's not epoxy. It's a UV (ultra violet) setting cement. Epoxy would require mixing a messy two part glue that would take many hours to harden after application. UV polymer based cement is much easier to apply and less wasteful. Once the lens is focused at the factory a small amount of UV cement is applied and the unit is then subjected to UV light which causes the glue to set up and harden within seconds, thus ensuring the lens remains in focus after handling and speeding up the manufacturing process.

Anyway, UV cement tends to soften when heated so using a hair dryer or heat gun to modestly heat up the lens module will facilitate unscrewing the original lens from the holder.

While it is possible to break the glue, using force can risk unexpected, unwanted results, so I recommend the heat method when removing factory mounted lenses from dash cams.

 

[Voldur]

How did you remove the lens from the lens mount? Do i need force to remove it from the lens mount maybe using heat gun or there is an existing mount one can buy?

I used 2 pliers. One to hold the lens and another to twist the mount.

As @Dashmellow said, use a hair dryer or heat gun to warm it up around the threads and it will make it easier.