Thread: C-mount lens recommendations, and if any, example images... for BMPCC

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  1. #1 C-mount lens recommendations, and if any, example images... for BMPCC 
    Senior Member jeclark2006's Avatar
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    I've looked at ebay, and while there seems to be a plethora of c-mount lenses, often they have such attributes attached as 'CC camera' or 'TV camera'. This suggests to me the lens coverage is for a smaller sensor than the Super16mm sized sensor of the Blackmagic Pocket Cinema Camera.

    Naturally when I look at official Super16mm lenses... I quickly find $1K+ lenses... which is out of my price range... of something like between $100-300.

    Also, my estimate of the 'normal' length lens for the BMPCC is about 18-20mm. So I'm not looking for a 6mm, but mostly in the 12mm-40mm range which would be 'somewhat wide' to somewhat telephoto.

    Currently I'm using my 14-140 Lumix zoom, which at about 50-60mm become 'unwieldy' without a tripod (actually 40mm seems to be the max for me these days with out some sort of support rest...)... given that is more than 2x the 'normal'... on the other other hand, at 140mm I can think about getting reasonably good surfer shots when the surfer is about 300 yards out...

    I've seem some number of Bolex lenses which may have sufficient coverage, although they were designed for regular 16mm. Even if I had to stop down from something like f/1.4 to 2 , or 2.8 to get better coverage that would be better than my current f/3+ on the Lumix.
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  2. #2  
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    Look for primes made for S-16 or 1", but forget zooms in that range. They either don't cover or they are expensive.
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  3. #3  
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    When I first got my BMPCC i was looking at a ton of ebay c-mount lenses, and I got burned on almost all of them.

    You can't trust c-mount lenses, they are old and not taken care of and they are also very soft and do not do the Blackmagic sensor justice.

    I had the following:
    Fujinon TV zoom - seller lied to me and said it covered s16, it vignetted heavily on my camera and wasnt parfocal. It now sits on my shelf.
    Canon TV zoom - was advertised to cover 1" (and i checked the model # too to make sure) but my copy couldnt even keep focus past 30mm and vignetted hard. Got a lemon, returned it.
    Wollensak 12.5mm f1.5 - fairly wide, no vignettes, and fast-ish. Soft as hell and full of chromatic abberations though. Got lucky and sold it off for 2x what I bought it for, because everybody wants a cheap wide for their BMPCC.
    Cosmicar 25mm f1.4 - good mid range focal length, kinda sharp (but barely keeps up with modern lenses) and covers fully. Still use it from time to time.

    In general, the image quality from these was terrible. Literally coke bottle quality of glass. Shots were blurry, flares were ugly, it was just old beat up dirty glass.

    I learned my lesson and now I just stick to m43 glass for low budget stuff and PL lenses with an adapter for bigger projects.
    Last edited by poematik13; 10-13-2014 at 01:16 PM.
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  4. #4  
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    For c-mount zooms, you might look into the Cinegon 18-90mm, Angenieux 17.5-70, Navitar 18-180, there's also the Angenieux 15-150 but these are typically very beat up and command a hefty price. You're not going to get a c-mount sub 15mm zoom, you'll have to go with a proper s-16 zoom and they are expensive. I'd also be surprised if any of these lenses were sharper than the 14-140 that you have now. The lenses listed are faster on paper than your lens but I wouldn't shoot wide open on any of them. Good Luck.
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  5. #5  
    Senior Member Steve Wake's Avatar
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    I have three.
    Schneider Cinegon 10/1.8 Careful, this has to be the one with the large front element, 55mm filter threads.
    Schneider Cinegon 16/1.4
    Bell and Howell, Taylor-Hobson (Cooke) 25/1.9

    First two were bought for about $500 total on eBay when the Pocket was new, Digital Bolex was not released, and the seller had no clue that they were useful for digital cinema. Glass was perfect, and I sent them in to Schneider in Torrance for CLA.

    The Taylor-Hobson still shows up on eBay in your price range, and is a nice lens, smaller than the others, a little long to hand hold - but great color. I have one clip available to view - my first test. To use filters with this one I had to epoxy a 52mm step-up ring to the Series 4.5 Filter adapter that comes with the lens.

    I've shot a lot with the 10 - just right for walking around, pretty discreet, but kind of big with filters because you have to step up to 77mm since it is a wide. I'm taking my time putting some personal pieces together, but I'll eventually post. Flares on the Cinegons are unique since they have a four bladed iris that shows as a diamond or cross. The 16 is not a favorite - need to stop down a lot, and the edges are always blurry - uncorrected spherical aberrations. But if you love swirly bokeh, that would be it's niche.

    I mounted each one in its own mft - C adapter. To get the distance marks accurate I had to cut my own shims from brass shim stock. They needed .002 to .007 inches of shims to get the distance marks right. This was critical for me because I got them mainly for discrete street shooting on a naked Pocket and I usually estimate distance.

    Here's a test clip with the "Cooke"

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    Yeah, I'd love to see some more of your stuff with these lenses. This one shot is gorgeous.
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    A friend and DoP bought off eBay a rather extraordinary Fujinon TV box lens for older 1" tube camera. To use it he dismantled the external casework so that he could manually operate it. That lens is both sharp for a zoom and has good contrast. I bought for a Bolex 16mm some years back a Fujinon TV-Z 16-160mm f1.8 lens, also for 1" tube or sensor. Both lenses are huge. There is a caveat when using these with the BMPCC and M4/3-C-mount adapters.

    The C-mount is attached to the lens body by a shouldered threaded collar arrangement. The collar fouls the M4/3 mount and adapter as it is too broad. Fortunately the collar is generous and material can be turned off it without compromising strength. The C-Mount bush inside also needed to have about 0.7mm skimmed off its rear clamping face "NOT" the the flange face.

    On the rear of these lenses is a mount adaptor which is fastened by six screws in the same pattern as a B4-Mount lens. The C-Mount bush locates in a neatly turned hollow surrounded by a thin-walled raised ridge. The piece has to be removed and this ridge also skimmed forward by about 0.7mm so that the collar maintains positive contact upon the rear shoulder of the C-Mount bush. It will otherwise spin around under the shouldered collar and you'll never get it off the camera again .

    This process then enables the flange face of the C-Mount positive contact with the face of the M4/3 to C-Mount adaptor, whereas it previously was hanging off a fraction forward.

    I commented less than favourably about this lens on dvinfo.net a few years back related to the SI2K. On the Bolex film camera in 1996 it had yielded a very pleasing image of good contrast. The moving zoom group was very baulky after several years of storage and the results to the SI2K were not so good. This may have been enough to throw focus off

    I opened it up to relube the movement. A few of the elements were a bit smokey so I cleaned them. The restored zoom movement and clean elements improved the lens significantly.


    You would need to have a lens engineer do this work for you as you get no second chances if you ruin something.When I first got this lens, it was externally in good condition. Apparently they were favoured as surveillance lenses.


    I could not find an example of the Fujinon 16-160 f1.8 TV-Z on eBay. This Vicon lens is patterned very similarly, except for the more forward p[ositioning of the apoerture ring closer to the zoom ring and a longer throat to the rear barrel and mount. It might have been a re-badged Fujinon TV-Z built to order for a camera type. With a fully closing aperture after f16 instead of the f22 on the TV-Z, there may be an opaque star printed in centre of the rear element which may mess with the bokeh.

    http://www.ebay.com/itm/VICON-TV-Zoo...item2ed7562be6


    These lenses should not be confused with the Fujinon 16-160 2.5 Z which is smaller and believed to be unsuited to single-sensor digital cameras.
    Last edited by Robert Hart; 10-15-2014 at 06:36 AM. Reason: errors - many
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  8. #8  
    Senior Member jeclark2006's Avatar
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    Quote Originally Posted by Robert Hart View Post
    A friend and DoP bought off eBay a rather extraordinary Fujinon TV box lens for older 1" tube camera. To use it he dismantled the external casework so that he could manually operate it. That lens is both sharp for a zoom and has good contrast. I bought for a Bolex 16mm some years back a Fujinon TV-Z 16-160mm f1.8 lens, also for 1" tube or sensor. Both lenses are huge. There is a caveat when using these with the BMPCC and M4/3-C-mount adapters.

    The C-mount is attached to the lens body by a shouldered threaded collar arrangement. The collar fouls the M4/3 mount and adapter as it is too broad. Fortunately the collar is generous and material can be turned off it without compromising strength. The C-Mount bush inside also needed to have about 0.7mm skimmed off its rear clamping face "NOT" the the flange face.
    I was wondering about that, as a number of the CC type lenses seemed to be too wide at the base to be 'adapted' to the M43 to C mount, minimal though that mount is...
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  10. #10  
    I ran across this a while back when I was looking at picking up some old C-Mount lenses off ebay for cheap...might want to check it out, although that would require Facebook and an accepted invitation into their closed group lol

    https://www.facebook.com/groups/cmountm43/
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