Mounting M12 Lenses
Note: Some super wide angle and fisheye M12 lenses may not be compatible with the H8PRO. The M12 lenses in our shop clearly list their compatibility in the product details. As a general rule M12 lenses with a back focus distance of 3.2mm or under are not compatible.
- Remove the C-Mount ring
- Screw the M12 to CS adapter ring onto the camera (Yellow Bag).
- Gently screw in your lens and check to see if it will focus. If it stops turning before it’s sharp you will need to remove the filter from the camera. If it still will not focus after removing the filter it likely has a back focus under 3.2mm and is not compatible. Take the lens back out.
- Thread the small black locking ring onto your lens.
- Screw the lens into the adapter until sharply in focus.
- It helps to connect the camera to a large screen via HDMI / Media Mod. If using the rear screen on the camera set the focus while zoomed in all the way in Photo mode. Zoom back out and take some pictures. Verify sharp focus across the entire image via GoPro app or PC.
- Tighten the locking ring against the adapter to lock the lens in place.
- You can also tighten the locking ring against the orange O-ring if desired.
Using the Slim M12 Mount
The H8PRO comes with an optional ‘slim’ mount dedicated to M12 lenses. Use this if you plan on mounting only M12’s or if you have a lens with an odd barrel or short threads that won’t move far enough into the standard M12 to CS adapter. Remove the CS-Mount ring using the supplied Allen key and use the four silver screws to mount the ‘slim’ M12 mount. It’s also designed to be reversible if you need a little more thread on the front of the camera.
Troubleshooting:
My camera turns off after just a few seconds! Use the side button to power on the camera instead of the top. Quick capture is triggered by default when you hit the top button so it will try and record. If no SD card is found the camera will display the message ‘Insert SD Card’ on the rear screen and then shut off.
My M12 Lens Won’t Focus! Try removing the glass filter from the camera to give the lens some extra room to focus. If the lens still won’t go in far enough it likely requires a back focus distance of less than 3.2mm and is not compatible with the H8PRO. The lenses we sell in our shop have their compatibility listed in the product details. As a general rule, M12 lenses with a back focus distance greater than 3.2mm should be fully compatible. Back focus distance is sometimes called ‘Flange Distance’. Lens manufacturers usually supply that information in their product details.
My footage looks pink! You are using an H8PRO-IR camera which is designed to image infrared light. Infrared appears pink in recorded footage. For ‘normal’ color you will need to install the supplied IR-Cut filter which prevents infra-red light from reaching the sensor. If your footage looks pink this filter is likely not installed, or you are using an ‘IR corrected’ M12 lens which is designed for full spectrum & IR imaging. Most M12 lenses have the filter installed on the back but for CS, C-Mount and other lens types you will need to add it for normal use.
My C-Mount lens won’t focus!: This usually means that you simply need to add the supplied 5mm C-Mount spacer ring to the camera before adding your lens. It comes mounted on the camera with a plastic cap screwed into it. Also make sure that the protective glass filter is installed in the camera as that has a small effect on the focus of lenses.
Dark spots in footage, especially when iris is closed down: Your image sensor or filter needs to be cleaned. Using an air puffer is usually enough to blow away any small particles that might have gotten on the sensor. A LensPen MiniPro is also a great tool for cleaning the small GoPro sensor. Also verify that there is no dust or debris on the back of the lens.
Images are blurry on one side with M12’s: Likely your lens is not perfectly aligned with the image sensor. Some lenses have looser thread engagement than others which may cause a very slight tilt. Try adding a layer of Teflon tape to the lens barrel before adding it to the adapter ring as outlined in the tips.
NOTE: We’ve done our best to accommodate the vast majority of M12, CS and C-Mount lenses on the market, however there will be some designs that aren’t compatible. M12 lenses that are extremely short, have odd shaped barrels or short threads may not work. M12 lenses must have a back focus distance (flange distance) of 3.2mm or higher. The lenses at www.back-bone.ca have their compatibility clearly marked. When buying M12 lenses elsewhere look for 1/2.3”, 1/2” or 1/1.8″ lenses. If you want to perform full spectrum or infrared imaging with your H8PRO-IR camera, look for ‘IR-corrected’ lenses. We recommend 1/2”, 1/1.8” or 2/3” C-Mount lenses with high resolution ‘megapixel’ optics.