Panasonic GH2 with Computar 12.5mm CCTV lens

There is a hair stylist not far from my house who is very film-able personality. I thought it would be a great opportunity to test out my newly acquired Computar 12.5mm f1.3.
She, however, didn’t want have anything to do with it, so I was stuck with video’ing just the kids. I was anxious to see how the lens performed indoors with whatever lighting that was available.
Fast lens are really expensive for GH2. Computer 12.5mm CCTV f1.3 is faster than pretty much anything else out there, and it costed me only $39! Add a $10 C-mount adapter, and voila, I have an excellent low light indoor lens!
Vignetting is too noticeable at the standard setting, so I used it in 1:1 crop mode.
Color grading with Colorista II tend to bring out quite a bit of noise from the shadows so I had to denoise the footage after grading. I was pretty careful with highlights so I would not blow them out, which is a true sign of a footage that looks videoish.
I think the clip below, so far, has been my most successful attempt to make GH2 look very filmy. The lens is not really sharp, but that’s okay since it tend to soften the image bit more like film. Now I really need to try this camera skydiving. I am anxious to find out how well it can handle the range in a harsh high noon sunny setting.
The focus ring set at infinity does NOT enable the camera to focus to inifinity. To overcome this, a screw under the focus ring pad needs to be taken out. It, then, can be turned beyond the infinity mark, enabling the camera to focus to infinity.

Here’s the location of the screw that needs to be taken out to achieve infinite focus. The rubber focus pad can simply be pushed out of the way to have access to the screw. No other parts need to be touched.
Screw that needs to be removed to achieve infinite focus on Computer 12.5mm

6 comments on “Panasonic GH2 with Computar 12.5mm CCTV lens

  1. Hi Bill,
    I have 2 questions about the COMPUTAR lens:
    1/ when you remove the stop screw, doesn’t the rear lens get too close to the GH2 sensor/shutter?
    2/ what brand name of C-mount/MFT adapter did you use?
    thanks, sean

  2. Hi and thanks for your tip. Following this I just got one myself and am perplexed on how to change the focus. It seems locked to very short distance focus no matter what I do with the focus ring. It’s as if the focus is frozen at 6 inches from the lens. The adapter I have appears to fit the lens quite perfectly. It is the Fotodiox brand C-M4/3. I can’t see any movement in the barrel when I turn the focus ring no matter what. The focus ring turns all the way from close to infinity. Removing any single screw doesn’t seem to change the limit of the focus ring turn. Frankly I can’t figure out what could be wrong. The aperture changes affect the image but the focus doesn’t change no matter what.

    • Since it does not have a screw, you might have to grind or file the rear part of the lens down a bit. You can google for exact instructions. I can’t seem to find the link at the moment. Good luck.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s