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Custom WB with BMCC Speedbooster is a bad idea on GH4
  • This little bastard...

    I now own 3 cameras. The GH2, BMPCC and the GH4. For the Blackmagic I bought the BMCC Speedbooster, so I can use it on the BMPCC and the GH4, if I would buy it any time soon. And I did - today. Excited about the Speedbooster working with my Nikon Glass and getting away with no vignetting in UHD mode (crop factor 2,3 becomes 1,472 like APS-C), I just wanted to give the Custom White Balance a try, since I had to dial in the correct color temperature on the BMPCC, I wanted the luxury back, to have the right settings at the push of a button.

    So I was just about to flex my finger and set Custom WB... when I remembered... my GH2 always using the mechanical Shutter, when taking the custom WB. Cause I want to use the GH4 a little longer, I dismounted the BMCC Speedbooster and took the Custom Whitebalance.

    Long story is short: Even with activated Electronic Shutter, the GH4 still uses the mechanical Shutter for Custom White Balance and can be damaged with attached BMCC Speedbooster. Since the SB touches the inside of the Shutter Casing and even leaves a mark there due the pressure of the adapter, when it´s attached.

    So better stay with the Blackmagic way of dialing in the color temperature or use your MFT Kit Lens - if you own one - to do the work.

    By the way.... am I the only one who sets custom WB? Cause I didn´t read about this issue anywhere else. At least the BMCC Speedbooster Users don´t care much about it and stick with automatic WB ;-)

    That´s it for today!

    Cheers from Austria! Stefan

  • 13 Replies sorted by
  • @0range

    I think it is best to use

    http://www.personal-view.com/talks/discussion/5770/metabones-lens-speed-booster-adapter-focal-reducer#Item_741

    I also think you do not read it as people do not use such adapter that is incompatible with camera.

  • The idea came from eoshd.com and youtube did the rest with it´s comparison videos :-)

  • Can you white balance using kelvin\ settings? I haven't used a GH4 yet, but my friend has one and I plan on using it on a shoot with my BMPCC specific speedbooster...but I don't want to ruin his camera either.

  • You can do it if you switch to any photo mode, in photo modes custom wb uses electronic shutter if it turned on. WB is shared between modes so you don't need to remove adapter.

  • Thanks for the heads up. I've shot with the BMPCC Speed Booster on the GH4 a few times (no problems) but hadn't considered custom WB would activate the mechanical shutter. Thank goodness I just stuck to the presets so far.

    Speaking of which, don't know why more people aren't talking about this combo, it reduces the GH4 crop to 1.33x, effectively APS-H. Looks lovely.

  • I have to eat my own words.

    Today I managed it to jam my shutter. What a great experience with a new toy which is 2 days young :-D

    So, if your GH4 tells you to shut it off and remain silent.... don´t get hysterical, like I did - just remove your BMCC Speedbooster and give it a gentle push against the curtain. Then the shutter curtain releases again, when you switch it on again. If you don´t push, it stays closed when switching on. So I guess.... it´s my lucky day.

    It seems to work as normal. It still does its 12fps in stills mode and now I know, that custom wb can be set with electric shutter in stills mode - THANKS f1lm3r!!!! - it hopefully won´t happen again ;-)

  • @0range, how did you manage to jam your shutter? Doing WB in video mode or were you just shooting video?

  • I was actually showing the stills mode of the camera to a friend and was switching around between mft lenses and speedbooster with nikon glass. So we shot a picture with mech. shutter and speedbooster ^^

  • It is an accident waiting to happen with an $1800 toy. Tempting fate.

  • It would be great to use these boosters on the gh3/4. If you set the camera into silent mode (page 1/9 of the custom menu) you can set custom white balance without activating the mechanical shutter in video mode, not sure if silent mode means no mechanical shutter ever?

    @Oedipax Thanks for the info, Interesting to hear you're using the bmpcc booster on the gh4, are your findings the same as others have reported? ie. some light marks on the "shutter guide" only?

    Still waiting to see what Metabones creates with the gh4 (specific) booster that is in the pipeline.

    Which lens combinations have you tested and found to work well? thanks :)

  • @matthere Silent Mode seems to work like you said - cool :-D

  • @matthere, Yes, slight marking on the shutter guide and that's all. I do think it's probably best not to leave said combo on the camera all the time, except for when you're shooting.

    I've tried it with my old Nikon manual primes: 24mm f/2, 35mm f/2, 50mm f/1.4. I don't remember if I've used it with the Samyang 85mm f/1.4 yet or not. But I probably wouldn't use that combo much anyway. The 24/35/50 all looked great.

    Infinity seems like it could be off by just a hair - i.e. when you rack to infinity, it feels like there's maybe just a hair more of focusing depth beyond what the lens is capable of reaching. But for such shots you could just shoot without the booster, as those aren't really shots that would benefit as much from the booster anyways.

    And about silent mode, yes, that's mandatory for this risky business! I will do a test later and see if custom WB in video or stills still activates the shutter when silent mode is engaged. It would be nice if it didn't.

  • Just tested, in silent mode doing a custom WB in either video or stills mode DOES NOT fire the shutter. So it seems if you set the camera to silent mode you should be protected from mechanical shutter accidents. YMMV, of course, and no guarantees :)