Crosstour CT9500 M12 Lens Tests

[Philaphlous]

Hey all, writing this from some new experience.

I recently broke off the glue that holds the stock lens of the CT9500 in place and replaced it with my older CT9500 lens which is different and a new Runcam RC25G lens. I was super excited about the Runcam RC25G lens since it is a F2.0 which I thought would be larger than my stock lens and the 2.5mm would be wide angle with less distortion. The results of my tests are in and below are each lens:

1) Runcam RC25G
Great looking lens. The glass looks really high quality and the all metal construction looks premium. Unfortunately that's where it all ends. Center sharpness is good but the edges are out of focus and you need to actually defocus the center to get the edges into focus, clearly the lens wasn't made correctly. Highly disappointing and I wouldn't recommend.

2) Stock CT9500 lens from the newer 4k50fps camera
It's actually a really good lens. The only thing that really stands out is the distortion is really bad because the lens is SOO wide.

3) Older CT9500 lens from the 2016-2018 version of the action camera
This lens actually appears to have the best qualities. The aperture is similar to that of the newer CT9500 lens. The sharpness is the best of all 3. The field of view is the most narrow of all 3. The MP isn't too terribly high, however, I think the new CT9500 lens gets away with it by having such a large FOV.


One thing I found interesting was the new CT9500 with the IMX458 did not have a lens with a IR filter in the back of the lens... I found this really surprising as I thought all cameras had to have an IR filter...apparently not... so I'm wondering if my older CT9500 lens should have the IR filter in it or not... I actually hoping to remove the IR glass which is glued in...I'll probably have to shatter the glass to get it out would be my guess... My thought is with the IR glass removed, it will be 1 pane less of glass and a slightly sharper lens...

[nutsey]

Could you please provide some pics of rear ends of your ct9500 lenses?

[Philaphlous]

I ended up taking apart after I put the middle lens on and broke off the IR lens. Judging by the pictures I took before IR / after IR, the red spectrum was cut out way too much. Definitely not worth it and it did change the focus point of the lens as well as increased sharpness slightly...



This is the RC25G left and stock NEWer CT9500 lens on the right.

[Philaphlous]

So I want to add this photo... as you can see the new CT9500 has been focused to the back glass of the lens...This is the new CT9500's lens... there's microscopic scratches all over the glass and this is what I was catching in the light in some pictures... Well actually my cleaning with IPA didn't eliminate all the smudges on the back glass so part of it was that ghosting...but still... I have another picture where you can clearly see an air bubble in the glass..... I guess that's what you get with cheap lenses..
I tried this with both other lenses, the OLD CT9500 and the RC25G lens and they looked all worse than the new lens...clearly this is probably why the images look a bit sharper and clear...

I should be getting the new 3.8mm lens here on Friday... however, I doubt I'll end up using it.. I'm like 99% sure I won't because apparently its going to be around a 27mm lens equivalent... so the FOV is going to be WAYYY too narrow...

I'll probably just stick with the stock lens and just ensure its focused properly and call it a day...

[Philaphlous]

So I ended up getting the 3.8mm lens. First, the lens looks to be great quality. The eBay listing says the housing is plastic but it's actually metal...lol. I tried to take off the ir glass and ended up removing another tiny lens that was held in by the screw for the ir lens. But I fixed it. The lens is definitely way to narrow for an action camera. Maybe if you had 2 action cameras, one with the wide angle and other with the narrow lens. The 3.8mm lens is definitely sharp but it is blurry on the edges. Again, I'm having trouble determining which lens is better, either the new ct9500 lens or the old one. I'm leaning more toward the new lens as being the best. Yes the distortion is the worst and angle is the widest but it also appears to give the best color and clarity.

[Philaphlous]

The 3.8mm lens is definitely the best looking lens of all others... the aperture does appear to be larger than the rest of the other lenses... the FOV is just too narrow and with the 1/3 sensor...it seems quite blurry on the edges again... I'm wondering if removing the IR glass would increase the sharpness on the edges... I already glued shut my CT9500 so I'd need another camera to test it out with...

[Philaphlous]

I think I'm also going to try this lens: https://www.ebay.com/itm/M12-x-0-5-B...R/184301971346

With the f-stop being 1.6 it's going to let in a heck of alot more light compared to the other lenses I've purchased... Plus with the 2.1mm, it's plenty wide like the stock lens...

I pretty well sealed up the CT9500 and glued down the stock lens...so it might be an interesting time trying this new lens if it appears to be indeed better than my stock lens...

I'm generally able to quickly identify if the lens is going to bring in more light by holding the end of the lens to a light then using a lux meter on my iphone and putting the camera against the back of the lens...it gives me a rough idea if it will indeed exceed the stock lens or not...then I'll give it a try.

[Philaphlous]

Figured I'd give a quick update here...


I ended up getting another lens after doing some digging -> https://www.ebay.com/itm/M12-x-0-5-B...53.m1438.l2649


The lens DEFINITELY has a much bigger aperture than the stock lens. Unfortunately due to it being a 2.1mm lens...I think its reaching the limits of the ability for a lens to be soo wide and sharp at the same time. The lens focuses quite evenly, however, it is not as sharp has the stock lens...

The new lens does much better in low light situations as its able to capture about 2x as much light as the stock lens...however, again, its not as sharp... Plus the lens is much longer and its focal length is much farther away from the stock lens...so the lens I got from ebay sticks out about an inch from the camera. I'm ended up using it on one of my security cameras which actually works quite well. I'm hoping to actually use it on my dash cam but just haven't had time to swap it out yet.

Ideally I'd like to find a lens that would be around 2.5-3.0mm with an aperture of f1.6-f1.8 and also be really sharp...that obviously would be ideal... but I think I'll have to settle for what came with the camera instead...once again, back to the drawing board.

I was also able to find this --> https://www.ebay.com/itm/112525296848 which I ended up getting just recently... I'll let you know how that lens works after I get it. I'm thinking 2.1mm will be ok for now...it might just be finding a lens that has the correct internal lenses to focus properly...hoping this F1.8 is a winner!