Laowa 10mm sharpness issue on BMPCC4K

I bought the new Laowa 10mm on BMPCC4K and found the lens is consistently soft and not focused well on my BMPCC4K - but the same Laowa 10mm lens is sharp on Lumix GH5. I contacted Laowa support and even replaced twice since I suspected it's the lens may be defective.

Upon more testing, I now found this could be a flange gap between BMPCC4K and Laowa 10mm lens. I would need help from this forum if anyone has any experience with Laowa 10mm on BMPCC4K re sharpness.

thanks.

DETAILS...
Here are my testing and initial findings:
1. Laowa 10mm on GH5 is sharp. Lumix 12-60mm lens on BMPCC4k is sharp.
However, Laowa 10mm on BMPCC4k is not sharp (tested with 2 new Laowa lens consistently).

2. After mounting the Laowa 10mm on BMPCC4K, the BMPCC4K focus assistant does not show the image is focus (if it's focus, it shows red lines). However, if i hard press the Laowa 10mm lens toward the BMPCC4K body for 1-2 sec temporarily, i can see the BMPCC4K focus assistance displaying most of the objects in red (ie. focused).

3. I asked several youtube channels who reviewed laowa 10mm. none of them use BMPCC4K and none of them complain the lens sharpness. Instead, they praise this lens is sharp. When i described the problem, one channel suggested my BMPCC4K flange distance gap.

4. I talked to BMPCC support. They can test my camera in their lab with other lens. However, if other lens (like my Lumix 12-60mm) are sharp, they will conclude it's not the BMPCC4K issue. They don't have Laowa by the weay. In my case, I tested my bmpcc4k with my Lumix 12-60mm (sharp). it's possible that BMPCC lab will just say my bmpcc is fine. it's the lens issue. (Remarks - Laowa support already disputes it's their lens issue since i tested with 2 new lens, and the lens is sharp on gh5).

I bought the new Laowa 10mm on BMPCC4K and found the lens is consistently soft and not focused well on my BMPCC4K - but the same Laowa 10mm lens is sharp on Lumix GH5. I contacted Laowa support and even replaced twice since I suspected it's the lens may be defective.

Upon more testing, I now found this could be a flange gap between BMPCC4K and Laowa 10mm lens. I would need help from this forum if anyone has any experience with Laowa 10mm on BMPCC4K re sharpness.

thanks.

DETAILS...
Here are my testing and initial findings:
1. Laowa 10mm on GH5 is sharp. Lumix 12-60mm lens on BMPCC4k is sharp.
However, Laowa 10mm on BMPCC4k is not sharp (tested with 2 new Laowa lens consistently).

2. After mounting the Laowa 10mm on BMPCC4K, the BMPCC4K focus assistant does not show the image is focus (if it's focus, it shows red lines). However, if i hard press the Laowa 10mm lens toward the BMPCC4K body for 1-2 sec temporarily, i can see the BMPCC4K focus assistance displaying most of the objects in red (ie. focused).

3. I asked several youtube channels who reviewed laowa 10mm. none of them use BMPCC4K and none of them complain the lens sharpness. Instead, they praise this lens is sharp. When i described the problem, one channel suggested my BMPCC4K flange distance gap.

4. I talked to BMPCC support. They can test my camera in their lab with other lens. However, if other lens (like my Lumix 12-60mm) are sharp, they will conclude it's not the BMPCC4K issue. They don't have Laowa by the weay. In my case, I tested my bmpcc4k with my Lumix 12-60mm (sharp). it's possible that BMPCC lab will just say my bmpcc is fine. it's the lens issue. (Remarks - Laowa support already disputes it's their lens issue since i tested with 2 new lens, and the lens is sharp on gh5).

I just posted a new thread in regards to this and also replied to another thread of yours. Maybe you could chip in on my thread if you have any other info

The lens flange retaining springs are weak on some samples resulting in loose fitting lenses at best and at worst the lens not registering properly against the face of the mount. There is an easy fix which involves putting a small flat bladed screwdriver under the spring tabs and levering the gap wider to create more tension. From an engineering perspective the lens and body flanges should be engineered / manufactured to a sufficiently tight tolerance to not need springs to keep the registration faces together.

The lens flange retaining springs are weak on some samples resulting in loose fitting lenses at best and at worst the lens not registering properly against the face of the mount. There is an easy fix which involves putting a small flat bladed screwdriver under the spring tabs and levering the gap wider to create more tension. From an engineering perspective the lens and body flanges should be engineered / manufactured to a sufficiently tight tolerance to not need springs to keep the registration faces together.

ok Thanks, so is this the case with all the Laowa met lenses on the BMPCC4k? I didnt have this issue when I owned the 7.5. Will I void the warranty or potentially damage anything doing what you said?

Also, any thoughts on which to choose between the 9mm 2.8 and 10mm f2

Thanks

I had this issue with all lenses on my P4k but some were worse than others. Modding the spring fixed them all. Likely you will void any warranty and yes you will damage your camera if you do it wrong i.e with too much force or the screwdriver slips and you stab your sensor.

I had this issue with all lenses on my P4k but some were worse than others. Modding the spring fixed them all. Likely you will void any warranty and yes you will damage your camera if you do it wrong i.e with too much force or the screwdriver slips and you stab your sensor.

Ah ok so its the spring in the camera mount you are talking about, I thought you meant something in the lens!

I think my camera is out of warranty anyway now and I'm sure I can do it carefully. I wonder why this guy in the video said it was just the laowa lens, and not others and was that bad