••Fujinon TV Lens on GH-1...Don't Drool••

okay. I'm in the same boat and have given up. now I have an $60 paper weight.

with 2x tele, it will not focus out far to infinity. only acts as macro focusing up close.

the end of the fujinon is basically butted up against the 2x tele so there is not
much of a gap if any.

not sure how super8 did his but definitely no cigar here.
 
Anyone ever get theirs to work? I've tried all kinds of things but I can't get this setup to work no matter what I do.
 
So I think I've found a way to make one of these lenses work but it took a lot of time, machining and parts from an old Nikkor tele lens, however in changing the focal length AND enlarging the picture enough to reduce vignetting at the widest angle, I introduced a good amount of chromatic aberration and barrel distortion.. I could NOT make a 2x extender work at all.
 
I am looking to try fitting a fujinon lens as well. If I use a lens with builtin 2x extender, will I still need a separate 2x extender to avoid vignetting?
 
The 2x extender does nothing for vignetting. The extenders only change the magnification, not the focal length. Your target will look magnified(if you use a 50mm lens with a 2x you'll get a 100mm lens..) but you will have the same vignetting. I built a jig to hold the 2x and the lens to adjust everything independently and I could find NO sweet spot for least vignetting and still keeping the image in focus. I really don't know how the OP and others built this and had it working with a 2x extender...
 
pix2pixels, the lens shown in your pictures is not a 2/3" lens - it is a 1/2". With Fujinon lenses, the first letter before the number determines the format and is:

C=1" C mount ie C5x20
A=2/3" B4 mount ie A12x9BERM
S=1/2" Bayonet mount ie S12x6.6BERM
D=1/2" C Mount ie D14x7.5BMD
TH=1/3" Bayonet mount ie TH17x5.5BRM
 
Svart said:
The 2x extender does nothing for vignetting. The extenders only change the magnification, not the focal length. Your target will look magnified(if you use a 50mm lens with a 2x you'll get a 100mm lens..) but you will have the same vignetting. I built a jig to hold the 2x and the lens to adjust everything independently and I could find NO sweet spot for least vignetting and still keeping the image in focus. I really don't know how the OP and others built this and had it working with a 2x extender...
Click to expand...

I think maybe your lens is a different type than the OPs. In any case what you say about extenders is incorrect. They do in fact enlarge the image circle. That you had zero distance between your rear element and the front element of the extender is telling. ;)
 
Tesselator said:
I think maybe your lens is a different type than the OPs. In any case what you say about extenders is incorrect. They do in fact enlarge the image circle. That you had zero distance between your rear element and the front element of the extender is telling. ;)
Click to expand...


They enlarge the circle, if you move them outside of their designed focal distance, but without changing the focal distance all you get is a larger out-of-focus picture that can't be focused by conventional means. By the time you move the extender to the point where you can focus onto the sensor, you have vignetting.

I have lenses made for 1/2 and 2/3 sensors. The 2/3 gets close but not enough. If we could find some TV lenses for 1" then those would work. I also have the exact same lens as the OP but I could not get it to work. The only range I could get without vignetting was about 75mm upwards. That pretty much wastes 3/4th of the zoom range.
 
I have the exact lens as well. I haven't tested it properly and I haven't tested it with a nikon doubler like the op did either so I dunno about that first hand. I've held it in front of the camera by hand with no doubler though. Doing that I can allllllmooooost get full coverage infinity focusing at the 75mm end. (There are a couple of lenses the op mentions.) I have the Fujinon 12.5mm 75mm f/1.2... the Sony 11mm - 70mm f/1.4 (Macro) - both for the 1/2" chips and the Fujinon 10mm - 100mm f/1.6 (Macro) for the 2/3". The later covers the sensor with infinity focusing from 40mm on out but it's not a C-mount. it's Sony's D-Mount which has the same registration specs but uses bayonet fins like this guy shows: http://www.dvxuser.com/V6/showpost.php?p=1946051&postcount=75 I guess I could see a doubler allowing it to cover in most of it's range and still focus to infinity. Of course holding up a lens like that is not a very conclusive test - even though I've taken about 50 different test shots like that with each one.

The later exhibits fairly strong signs of CA fringing too. But the first two mentioned look like dang APO lenses... extremely sweet! So I really want to try and adapt them. Remember, he's replacing the mount on his too. Right? The bummer with the two c-mount lenses it that it will not screw onto a C-nount adaptor at all - or so I think by looking at these:

1.JPG
JYCM434.JPG


JYCM432.JPG
JYCM435.JPG


http://cgi.ebay.com.au/Bolex-16MM-C...ccessories&hash=item4aa06f2c3d#ht_2480wt_1088

I'll post some actual information on using these with the GH1 after I get serious with them - probably in a few weeks or a month.
 
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I have one of those adapters. I could not get it to be vignetting free unless zoomed way out.
 
Just got my Canon Video lenses modified!

Just got my Canon Video lenses modified!

I finally got around to working on a couple Canon J13x9B 2/3" video lenses that I had. I put a Nikon mount on them and mounted them on my Nikon-m4/3 adapter. Works great! :laugh: They are 9-117mm @ f/1.6. They have a built-in 2X extender, and when it is engaged, the whole GH1 frame is covered throughout the zoom range. With the extender the zoom is 18-234mm and the aperture would be f/3.0 or so since I think it creates a light loss of 2 stops. Without the extender the full frame is covered at 117mm (maybe a little darkening of the corners, but not much). The focus holds throughout the zoom range. I'm a happy camper.
Now I just have to figure out some sort of lens support.
 
lvlinux said:
I finally got around to working on a couple Canon J13x9B 2/3" video lenses that I had. I put a Nikon mount on them and mounted them on my Nikon-m4/3 adapter. Works great! :laugh: They are 9-117mm @ f/1.6. They have a built-in 2X extender, and when it is engaged, the whole GH1 frame is covered throughout the zoom range. With the extender the zoom is 18-234mm and the aperture would be f/3.0 or so since I think it creates a light loss of 2 stops. Without the extender the full frame is covered at 117mm (maybe a little darkening of the corners, but not much). The focus holds throughout the zoom range. I'm a happy camper.
Now I just have to figure out some sort of lens support.
Click to expand...
Hey I've got a similar Canon and I'm curious how you put the nikon mount on? Where you got it? Also, I've got the hotrod PL adapter and when there is cash of course a nice set of primes get rented but for messing around is there any way that anyone knows of to convert/adapter a cheap c-mount to PL and if that would even work? I realize I may not get the wide portion of the lens but......I wish a nice fast PL zoom that could cover the whole sensor would fall in my lap.
 
Also, with a lens that covers an area similar to 16mm, then being 2x-extended so it covers the GH1 sensor, Do the DOF characteristics still resemble 35mm because the GH1 sensor remains the same or do you get a greater DOF?
 
jgardner said:
Hey I've got a similar Canon and I'm curious how you put the nikon mount on? Where you got it? Also, I've got the hotrod PL adapter and when there is cash of course a nice set of primes get rented but for messing around is there any way that anyone knows of to convert/adapter a cheap c-mount to PL and if that would even work? I realize I may not get the wide portion of the lens but......I wish a nice fast PL zoom that could cover the whole sensor would fall in my lap.
Click to expand...

Don't know for sure about C-PL, but do you mean put a PL mount on a C mount lens? Should work I guess, but probably your biggest problem would be you'd have to get a PL mount, and wouldn't that mean buying a PL lens? Why not just use a C-m4/3 adapter? If you meant a C-PL adapter then I don't think that that is possible at all. The C mount has a very short flange distance, and PL is much greater, so even though it would be physically possible, you'd only be able to focus out to a few inches, if that.

As for how I did it - for one lens I used a cheap Nikon extension tube deal with the screw-in pieces and just ground down the smallest piece till it was the right distance and JB-welded it to the existing lens mount. I don't have a grinder or anything, so I just rubbed it by hand against some walkway bricks to grind it down (hey you gotta use what's available :-)
As for the other lens, I used a different (and better) Nikon mount on it. It fit right on without grinding it to change the distance. I super-glued the Nikon mount on first, just to hold it in the right spot, then put on the JB Weld. Then I used the back-focus adjuster on the lens to get it perfectly matched up to the GH1 so it would hold focus throughout the zoom range. I'll try to post some pics sometime soon if I have time.
 
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jgardner said:
Also, with a lens that covers an area similar to 16mm, then being 2x-extended so it covers the GH1 sensor, Do the DOF characteristics still resemble 35mm because the GH1 sensor remains the same or do you get a greater DOF?
Click to expand...

A video lens at 18mm will give the same DOF as a 35mm lens at 18mm or a MF or LF lens at 18mm or a C mount or any other lens at the same focal length.
The only differences are the size of the image circle and the field of view, based on the amount of coverage or lack thereof.

DOF is directly linked with aperture and focal length, not sensor size, but since the sensor size of the GH1 is similar to 35mm movie film (albeit somewhat cropped), the DOF should be similar with lenses that are providing the same filed of view.

In other words, at 45mm and f/5.6, the GH1 will be identical in DOF, and close to the same field of view (portrait range), as 35mm cinema at 45mm and f/5.6. My DVX100 (1/3" sensor) at the same settings will ALSO be IDENTICAL in DOF, but much more telephoto in it's field of view. A full-frame 35mm camera (Canon 5D, Nikon D3, Nikon F2, etc.) with a 45mm lens at f/5.6 will also be identical in DOF, but will have a wider field of view (normal range).
 
lvlinux said:
A video lens at 18mm will give the same DOF as a 35mm lens at 18mm or a MF or LF lens at 18mm or a C mount or any other lens at the same focal length.
The only differences are the size of the image circle and the field of view, based on the amount of coverage or lack thereof.

DOF is directly linked with aperture and focal length, not sensor size, but since the sensor size of the GH1 is similar to 35mm movie film (albeit somewhat cropped), the DOF should be similar with lenses that are providing the same filed of view.

In other words, at 45mm and f/5.6, the GH1 will be identical in DOF, and close to the same field of view (portrait range), as 35mm cinema at 45mm and f/5.6. My DVX100 (1/3" sensor) at the same settings will ALSO be IDENTICAL in DOF, but much more telephoto in it's field of view. A full-frame 35mm camera (Canon 5D, Nikon D3, Nikon F2, etc.) with a 45mm lens at f/5.6 will also be identical in DOF, but will have a wider field of view (normal range).
Click to expand...

Almost true, you've forgotten about the circle of confusion. Try a quick experiment with a depth of field calculator. http://www.dofmaster.com/dofjs.html

With a 45mm at f4.5 on a 5D sensor i get a depth of field of 4.16 feet
With a 45mm at f4.5 on a GH1 sensor I get a DOF of 2.02 feet

The main difference is the circle of confusion, inherently tied to sensor size. It's easy to forget because no one understands it. Hard to understand because it's confusing. But it does work and should be remembered.

A side note regarding field of view:
45mm on a 5D sensor = 22.5mm on a GH1 sensor
With a 22.5mm at f4.5 on a GH1 sensor DOF is 8.54 feet

Bigger sensor has a bigger circle of confusion and will always have better depth of field.
 
weaponsofthenow said:
Almost true, you've forgotten about the circle of confusion.

Bigger sensor has a bigger circle of confusion and will always have better depth of field.
Click to expand...

Right you are! I completely forgot about the circle of confusion.

However "better" is not the word - "shallower" is more appropriate. Sometimes you want a more shallow DOF and other times you want a very large DOF.

Thanks for clearing that up.
 
I know this thread's be inactive for about a month, but I had a question a way of getting a fujinon c mount zoom to work on the gh1 w/o vignetting.

Someone mentioned the possibility of removing the c mount and "gluing" a nikon mount from ebay onto the fujinon and then just attaching that to NIKON 2x teleconverter and that to NIKON to micro 4/3rds adapter.

1. Is that correct? Anyone tried this yet?

2. Someone mentioned somehow using an cmount to m42 and m42 to nikon, etc.... How would this work, if at all?

3. Lastly, what about this method (I'm sure I'm missing something because it seems too easy):

A. Attach a c-mount to nikon adapter to the fujinon like this:
http://cgi.ebay.com/lens-adapter-49...ultDomain_0&hash=item5adab79128#ht_1551wt_769

B. Then attach that to a Nikon 2x teleconverter

C. Then all of that to a nikon to micro 4/3rds adapter to the gh1

Am I right that this later method won't work because the original cmount to nikon reverse mount will simply making the zoom a macro lens with very limited focusing ability?

4. ONE MORE THING. How about something like this:

A. remove the c mount from the fujinon and attach a nikon to canon mount;
B. attach that to a canon eos 2x teleconverter like this: http://www.keh.com/camera/Canon-EOS-Lens-Converters/1/sku-CE100090307240?r=FE
C. then attach to gh1 via a canon to micro 4/3rds adapter??
 
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qwerty123 said:
I know this thread's be inactive for about a month, but I had a question a way of getting a fujinon c mount zoom to work on the gh1 w/o vignetting.

Someone mentioned the possibility of removing the c mount and "gluing" a nikon mount from ebay onto the fujinon and then just attaching that to NIKON 2x teleconverter and that to NIKON to micro 4/3rds adapter.

1. Is that correct? Anyone tried this yet?

2. Someone mentioned somehow using an cmount to m42 and m42 to nikon, etc.... How would this work, if at all?

3. Lastly, what about this method (I'm sure I'm missing something because it seems too easy):

A. Attach a c-mount to nikon adapter to the fujinon like this:
http://cgi.ebay.com/lens-adapter-49...ultDomain_0&hash=item5adab79128#ht_1551wt_769

B. Then attach that to a Nikon 2x teleconverter

C. Then all of that to a nikon to micro 4/3rds adapter to the gh1

Am I right that this later method won't work because the original cmount to nikon reverse mount will simply making the zoom a macro lens with very limited focusing ability?

4. ONE MORE THING. How about something like this:

A. remove the c mount from the fujinon and attach a nikon to canon mount;
B. attach that to a canon eos 2x teleconverter like this: http://www.keh.com/camera/Canon-EOS-Lens-Converters/1/sku-CE100090307240?r=FE
C. then attach to gh1 via a canon to micro 4/3rds adapter??
Click to expand...

1. Yes and Yes (i have not with a c-mount but a b3 and b4 mount and it would be a similar thing, except the distances are different, so the Nikon mount would have to be pretty far up the c-mount lens's barrel to get the rear glass close enough to the teleconverter)

2. Probably wouldn't work. Would mount, but you probably couldn't focus to infinity - probably not even close.

3. nope, that would create a super-macro lens, if anything, and you could only focus to a couple inches or so.

4. That would work but it would be more expensive than method #1.

Basically however you attach it to the GH1, as long as the flange distance is correct, it will focus correctly, and if you have the teleconverter then it will make the image larger so a 2/3" lens or bigger will cover the GH1 frame.

Let me know if you need more info or help.
 
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