Group Purchase of the 3.8mm lens

[Ricard]

Good lord, you should come and focus mine. I'll pay for your flight.

I did the half assed version of yours and dialed it on on a good monitor shooting out the window and slowly turning the lens until the shed 50 yards away looked best.

There's certainly about a 1/4 more turn on the lens this time from when I focused at 6 feet, so hoping its pretty crisp.

I think I can get out tomorrow to shoot a guys corn field and corn stand. Should tell the story.

 

[Fred Vandeman]

I'm not up to speed on the latest. Where do we stand with a lens for group purchase?

 

[ajcarter]

Good lord, you should come and focus mine. I'll pay for your flight.

I did the half assed version of yours and dialed it on on a good monitor shooting out the window and slowly turning the lens until the shed 50 yards away looked best.

There's certainly about a 1/4 more turn on the lens this time from when I focused at 6 feet, so hoping its pretty crisp.

I think I can get out tomorrow to shoot a guys corn field and corn stand. Should tell the story.

can these be used on any action cams? like firefly 7s 0r 8s? Thank you!

 

[NightStorm]

I bought a refurb H4B after losing my original H4B + Peau lens into the drink (along with everything attached to it). Recalling this thread I decided to try one of the AliExpress lens mentioned earlier. Given all the factors, such as price, the time to receive from China, and the risk that one or both of the lens might not be so great I ordered two, one a 3.4mm and the other a 3.8mm.
I'm glad I did. Everything finally arrived and today I've had some time to crack the GoPro lens seal on the camera and try the two out. Unfortunately there are no markings whatsoever on the lens and they were both packed together in a small bag. I've no idea which is which and the focal lengths are so close that even when I take pictures with them I'm hard pressed to see which of the two has more in the field of view. However the back of one lens has a reddish filter (I presume it is a filter) while the other is bluish. The Ali website show the back of the 3.8 and it shows reddish, that matches what I suspected from the photos I've taken.
I did very careful focusing with each, marking the lens, and rotating in each direction small increments and taking photos at each point. The 3.4 (or at least the one with the bluish back) seems way superior to me in sharpness. Curiously the 3.8 looks flatter and seems to have less contrast than does the 3.4mm.

Below are two sample shots. It is late in a bad, overcast day here so they are not high-contrast to begin with.

Here is the 3.4mm:



And here the 3.8mm: