The Nikkor “O” CRT 55mm f/1.2 Lens: A Recipe for Lovely

[Michael Erlewine]

This lens is very hard to mount due to very odd threads. I finally mounted it with a clamp-on tube as close to the flange as I could get. Even, then, there is very little range and it is too close for my taste. So, there is the mounting and the range and the sheer heaviness of the lens. It is a lump. And you are going to have to shoot it wide-open unless you have the electrical connection to close and open the blades. Better hope that it comes wide open! I had to make sure the seller would set it to wide open before shipping.

I can live with that, but when I stack fairly close, looking to see what degree of sharpness is there, I must have missed the “sharpness” in passing. LOL. There wasn’t any sharpness there worth my trouble and I usually go to a fair amount of trouble to find things out.

So, heavy, ultra-limited range, very difficult to mount, and then not really sharp.

This might be a lens that folks like Jakov Minić, those who are skilled in atmospherics, might like.

Here is a multi-level stack using the JML 56mm. What you see is all the resolution/sharpness I can get, and this photo has been dressed up in post in its “go-to-meeting” best.

I see no reason to use it. However, if anyone wants it, I’m happy to sell this copy WITH a Nikon-F adapter included.

[Jack Dahlgren]

And you are going to have to shoot it wide-open unless you have the electrical connection to close and open the blades. Better hope that it comes wide open! I had to make sure the seller would set it to wide open before shipping.

I see no reason to use it. However, if anyone wants it, I’m happy to sell this copy WITH a Nikon-F adapter included.

Actually, there are just a few screws holding the cover plate so it is easy to set or remove the shutter diaphragm:
Unscrew the front cell
Remove the six screws
Lift the cover plate
Remove the 4 screws holding the shutter diaphragm
Lift the shutter out
Move the actuator lever to open position
Open the shutter using the actuator pin
Put shutter back in (or remove entirely if you just want to use wide open)
Put cover back on
Screw front cell back in.

I agree that this in not a great lens for Michael’s type of work.

[Fons Baerken]

Here is how I find out the best way to connect the 55mm CRT to my Nikon bodies : In this way you won't hit anything in the mirror chamber

All you need is a couple of M39/nikon rings (very cheap) :

1/ screw the first ring with the nikon side facing the lens;

2/ screw the second ring with the nikon mount normally.

3/ screw both rings in thoroughly. That's it !

Thus you attach your lens like any one without worry...

I tried this at my D500 first but ERR messages appeared although the camera didnt stop shooting, still not enough mirror clearance?
later i added another ring as spacer and tried it on the Df with the aperture lug turned in, no error messages on the Df.

[Fons Baerken]

I tried this at my D500 first but ERR messages appeared although the camera didnt stop shooting, still not enough mirror clearance?
later i added another ring as spacer and tried it on the Df with the aperture lug turned in, no error messages on the Df.

Any thoughts?

[Jack Dahlgren]

Any thoughts?

ERR probably means the lens is hitting one or more of the contacts in the body.

[Fons Baerken]

ERR probably means the lens is hitting one or more of the contacts in the body.

thanks Jack

[Bjørn Rørslett]

Keep the retaining nut on the rear part of the lens. If this is removed the lens will be seated deeper into the camera and the danger of it touching something inside the camera throat is increased.

Flipping up the aperture lug on the Df won't influence the basic problem of interfacing the 55 CRT with any Nikon (D)SLR.

[Fons Baerken]

Thanks,
thats what it looks like one spacer ring(jamnut) and 2 adapters(m39-f-mount) back to back following Francis' suggestion, so the nut is flush with the adapter mount, actually slightly inside.
Any way of enlarging, or extending the focal distance?

[Dr Klaus Schmitt]

Sure, a very thin M42 helicoid from ebay, a M39-M42 ring in front, and a thin (macro) M42-Nikon adapter ring and you're all set!!
Tht first ring and that Nikon adapter you seem to have already though...

[Akira]

Thanks,
thats what it looks like one spacer ring and 2 adapters back to back following Francis' suggestion, so the nut is flush with the adapter mount actually slightly inside.
Any way of enlarging, or extending the focal distance?

The best (and probably the only) way is to mount the lens on a mirrorless camera.  I'm not joking.

You can mount the CRT without the retaining ring via BR-15 and F to Canon EF adapter on a Canon body, as its flange back is shorter and an EOS body doesn't have the aperture lever to interfere.  I've done that on EOS 5D MkIII.  The focusing distance IS shorter, and the magnification factor is closer to its designated range, but the difference is almost unnoticeable.

[Fons Baerken]

Akira i have a pana gx1 lying around I never use, what adapter do you recommend?

[Fons Baerken]

Actually on the 1 V1, LF1 @f/1.2





handheld waiting for a lull in a light breeze

[bobfriedman]

Nikon D3 ,CRT Nikkor-O 55mm f/1.2
1/50s f/2 at 55.0mm iso200

[Jack Dahlgren]

Thanks,
thats what it looks like one spacer ring(jamnut) and 2 adapters(m39-f-mount) back to back following Francis' suggestion, so the nut is flush with the adapter mount, actually slightly inside.
Any way of enlarging, or extending the focal distance?

I just use a single adapter with the jam but up against it. It keeps it in place just fine.
If you want to move focus out closer to infinity you need to bring the lens closer to the sensor. On the F mount this is not possible as the lens body can only go so deep into the camera. You could gain a few mm more depth by shaving off the protruding part of the lens barrel, but I wouldn’t recommend. A mirrorless camera body would seem the easiest solution if you want infinity focus. Going the other direction can be achieved by mounting ina M extender or PK11, or any other sort of thing. I think I used a teleconverter with reasonable results, but my
Memory may be mistaken.

[Akira]

Akira i have a pana gx1 lying around I never use, what adapter do you recommend?

I have tried a combined M39 (LTM) to m4/3 adapter like this:

https://www.ebay.com/itm/Leica-L39-M39-Lens-To-Micro-M-4-3-M43-Adapter-GH1-E-P2/352184037797?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D44040%26meid%3D9b4c4a1bd9d3414eaf817362cb7470b9%26pid%3D100623%26rk%3D3%26rkt%3D6%26sd%3D250715657046%26itm%3D352184037797&_trksid=p2047675.c100623.m-1

It enable you to focus much further, but I failed.  This way the lens is set too close to the sensor, and the lens is mechanically focused past infinity.   

So you would need to use some sort of extension, like an L39 extension tube or a m4/3 extension tube.