FUJINON-TV ZOOM LENS - H6x12.5R 1:1.2/12.5-75
Like many GH1 users one of the challenges and the joys is experimenting and finding reasonably priced c-mount lenses. To get full coverage of the m4/3 sensor, you generally need to use a 25mm c-mount lens or higher otherwise you get a “peep hole” effect as well as vignetting because the image circle of the lenses that are smaller than 25mm will not fill the whole sensor. Despite these drawbacks people are still finding these lenses a lot of fun to shoot with. Many people have done a number of tests with c-mount prime lenses with both not so great and wonderful results. But not a lot of folks have explored c-mount zoom territory and it seems that more and more are finding ways to use c-mount zooms in a filmmaking capacity.
I have posted a few preliminary tests with an Angenieux and Schneider zoom here on this blog and despite the image circle not filling the sensor I still love the look of these lenses. Some folks have figured out a way around the issues with image circle size by converting the mount of the c-mount lens with a Nikon teleconverter but you lose the fast aperture as well as your wides. Converting the lens is one solution but you need to have some skill to be able to do that. So for those who are willing to live with the current limitations of c-mount zooms on a m/43 sensor I wanted to add some more initial findings of another zoom lens: The FUJINON-TV ZOOM LENS H6x12.5R 1:1.2/12.5-75 The advantage of this zoom lens is that it’s fast at f/1.2 and you can use your GH1 in low light situations. And for close range work, these lenses are quite sharp especially in the higher focal ranges and are reasonably priced so it’s worth a little experimenting especially if you can find a good deal on one. Many users who bought this lens found out they couldn’t use them because the lens mount cannot properly fit the c-mount to m 4/3 adapter.
After some brainstorming and experimentation, I figured out a very cheap and pretty solid solution to getting this lens to mount on my Hawk Peng c-mount to m4/3 adapter using the magic of Scotch Blue Painters Tape. I love this tape because it’s removable and thin and can be used almost anywhere. It’s like a poor man’s gaffers tape. Here’s what I’ve done in order to mount this lens:
1) Remove the threaded black cap on the back of the lens that holds the c-mount plate in place.
The c-mount plate is silver looking and removable.
2) Once you remove the plate, you’ll cut to size a 1 inch long tiny piece of blue painters tape and place it along the flat edge of the plate.
3) Place the c-mount plate back on the lens making sure it’s flat and snug.
4) Screw the c-mount to m4/3 adapter to the lens first making sure that it is not loose and sits evenly on the mount.
5) When you mount the lens, you can slowly twist the lens so that the scales are pointed up and where you want it to be.
6) Be aware, that the lens is snug but not permanent. It should really not go anywhere unless you twist it off.
7) Replace the tape when you feel it starts to jiggle out of place.
JUST REMEMBER…
- When using this and most c-mount zooms you are still going to get a smaller image circle and a little bit of vignetting depending on your focal length but the lens will sit snugly in the mount. You can also adjust focus, aperture, and focal distance through out the zoom range with very nice results.
- You can use the 2x digital zoom on the GH1 in order to get a full frame picture for both still and video but be aware there will be a resolution loss that will be equivalent to SD resolution. For those who are producing web content or DVD content then this may not be so bad of a loss.
- One thing that I did notice with the FUJINON-TV ZOOM LENS is that when you are in digital zoom mode it is a little shy from infinity focus when using your widest focal range. With out digital zoom engaged you are able to focus to infinity.
Comments
Thank you Gary! Very useful to see the results before slogging away on eBay to find the perfect lens! The loss of contrast on 2x digital is an eyeopener too! Good stuff and please keep it up!
Pat
Hi Pat, Yes, I agree there is some loss in contrast with the 2x digital engaged but overall I am still surprised that this lens can give some pretty sharp images. I’ll post some comparisons shortly.
I came across your post searching about the c-mount and using it on a canon.
I realize that your camera is not a canon, but have you come across anyone that has?
Hi Jeremy,
Canon cameras have larger sensors than the m4/3 system so they will generally not work with c-mount lenses. The Micro Four Thirds system uses the sensor size (18 x 13.5 mm) which is small enough for c-mount lenses to work fairly well 25mm and above. You can check out more info and samples at getdpi.com.
-G
Any video of this lense in action in low light?
Unfortunately I don't have the lenses anymore. I sold them. They were pretty decent in low light. Not mind blowing. I'd say you still have to stop down for sharpness so the lens is more like f/1.4.
I've sold these lenses and have been trying to find another one to purchase and test on the GH2.
Just as an FYI the older version H6x12.5R with the blue tape fix allowed you to achieve infinity focus. The newer version of the H6x12.5R does not work. :(
I did find a new one but it is not the same. I just discovered this and will post the physical differences. The model number is exactly the same but there are slightly different versions of this lens. The one that works has a different aperture ring and also the c-mount cap is a little wider.
Hello Gary. Thanks for posting your lens adventures and findings.
I've just acquired a different c-mount Fujinon TV Zoom. This one is quite old, it's model C16x175B 17.5mm-105mm & f1.8 . It used to be fitted to a 'line test' camera at the animation studio I work at.
I notice that like your lens described above, the c-mount on the rear of the lens can be unscrewed and exposes another larger diameter threaded lens mount. I wonder what format this is? I saw one ebay seller for a similar lens state that this was M42 (old Pentax, Prakitika, Zenit etc.), butI've got an M42 adaptor and that's slightly larger and not the same as this thread. I found another reference that suggested this thread might be special to some older Sony TV cameras???
Anyway, it strikes me, that by removing the cmount and somehow coupling to this unknown (and larger) lens mount, then maybe these lenses could give a larger image circle after all. I'm hoping to buy a GH2 soon and would really like to put this old lens to good use…
many thanks
Chris
Whoops my lens is actually C6x175B not C16X175B as I wrote above.
I guess C means 'c-mount' , 6X -zoom factor and 175 code for the widest angle, not sure what the 'B' at the end means…
Thanks Chris for your post. I will look into this and ask R.J. the ebay seller jinfinance to see if he can create a custom mount from the secondary M42 type thread. It definitely is not M42 and it is not a T-mount. Like I said I bought a brand new Fujinon H6x12.5R and it is different from the old ones that I sold. The thread mount for the secondary mount is a little bit wider and so it does not give infinity focus with my blue tape fix. I’d first try to see if you can try the Blue tape fix and see if you can get infinity focus with the lens you have.
I’ve purchased many different Fujinon c-mount zoom lenses and it’s very random. Some lenses totally clear and look to work with a c-mount to m4/3 adapter and they won’t work to give you infinity focus. This is true for the Fujinon H6x12.5D. It won’t work right though it fits to c-mount to m4/3 adapter perfectly. You can modify it by removing the screw underneath the rubber ring of the focal ring so that you go beyond infinity focus but your scales are off and the lens focal ring can rotate out of the barrel. This is currently how I would do it.
I’m still on a hunt for the older Fujinon H6x12.5R. If I only knew the GH2 was just around the corner. Oh, well.
Let me know how the Fujinon C6x17.5B works out for you. And I do not know what the B means either. If you do find out let us know.
Thanks!
Gary
hi gary.
i just bought the same exact lens you show in the photo (Fujinon H6x12.5R) I'm tryin' to adapt it to my GH2 but i think my cmount to m43 is too thick and do not fit well because i can't easily achieve infinite focus (i'm tring to find a very slim adapter).
what kind of adapter do you used?
thanks!
Hi fegato,
Yes, I must update this page. I’m surprised people are still trying to get this lens to work.
The c-mount you want is from Hawk Peng. His user name on ebay has changed to the following:
http://myworld.ebay.com/hawks_factory/?_trksid=p4340.l2559
You must use Hawk Peng’s c-mount that will get you closer to infinity focus than the other c-mount adapters and is one of the best.
I will post an update on this lens in terms of getting it to infinity focus. Sometimes the tape fix may not be enough.
-G
I have modified this type of lenses and already sold a few. Can focus to infinity throughout the zoom:
http://cgi.ebay.com/MODIFIED-C-mount-FUJI-FUJINON-12-5-75-f1-2-TV-lens-/180690242492?pt=Camera_Lenses&hash=item2a11fa4bbc
Hello, I found a FUJINON-TV Zoom Lens/H6x 12.5R in my house used in the past by my father. What is this lens and how do I sell?
Very interesting Ed. I have also found another way to modify the lens as well but at the end of the day in order to use this lens you need to stop down by a half to a full stop to get sharpness. Hopefully you’ve found a nice solution. Thanks for the note.
Just go on ebay and sell the lens. Do the research and read the articles or go online and see what others have done or sold it for. Good Luck!