"new" 55 f1.2

[Roland Vink]

Very nice pictures of the Solitaire.  But I am somewhat disappointed about the bokeh which looks very unresty to me.

The 55/1.2 does not render backgrounds with the smoothness of the 58/1.2 Noct, it is very "textured". It can be used to good effect but care must be taken when choosing the background. The foreground bokeh on the other hand is very smooth...

[richardHaw]

bubbles 

[armando_m]

Lubricants leaking onto the aperture blades will cause the noted behaviour. Some lens designs are particularly prone to getting this problem, with the 55/2.8 Micro as the most infamous example. Also the AF 20/2.8 saw a good deal of these issues.

Thanks for commenting, I'll certainly report how things go after cleaning the aperture blades

Since the stop down activation is the assumed to be the same mechanism used by both the DOF preview button and the camera shutter firing cycle, you should be able to reproduce and observe the problem by watching the lens front and firing the shutter...or pushing the DOF preview button... numerous times.  I had a AiS 135/2 that had an intermittent aperture closing issue, but the technician who fixed it didn't say what he did to fix it.  Is it possible that the coil spring gets tired and weakened?

Thanks for the suggestion, setting the lens to F16 should make it easy to observe

But a completely different scene so perhaps not a good way to evaluate the problem?
Also a failing flash could vary its exposure as well, though the DOF button trick seems to lean towards a camera/lens error.

Why not try to recreate this under a more controlled setting? Camera on a tripod, constant light source, take lots of pictures and watch for varying exposure.

Charlie,

I did try the sunny 16 rule, (1/125 f/16 ISO 100)and the behavior became much more easier to obtain, like 1 every 2 shots,  the example  studio shots were done at f5.6 and the problem happened twice in a series of perhaps 20 shots.
In my experience when a flash fails, one gets an underexposed image, not over exposed.

[Peter Forsell]

Great lens Armando. I hope you get all the small annoyances fixed soon.

One question about the first picture. I see there is a landline telephone. Is it still in use?

[richardHaw]

http://richardhaw.com/2017/03/15/repair-nikkor-s-c-55mm-f1-2/
The Nikkor-S.C 55/1.2  teardown

[armando_m]

Great lens Armando. I hope you get all the small annoyances fixed soon.

One question about the first picture. I see there is a landline telephone. Is it still in use?

yes , it is actually a digital phone connected yo the network

[armando_m]

http://richardhaw.com/2017/03/15/repair-nikkor-s-c-55mm-f1-2/
The Nikkor-S.C 55/1.2  teardown

Thank You Richard

This is very helpful

ok, today activity: Disassembled the lens ... and cleaned it , the offending grease was outside the optical assembly, also took the time to clean the focus helicoids.

Tested with a few F16 shots and it seems to work correctly

[armando_m]

an image at 1.2


While I was doing this I checked the 50 f1.8 E series, and it also has a laggy aperture mechanism , more than what it was on the 55 f1.2

[Randy Stout]

Armando:

I like the colors and feel of this image.  Dreamy.

Randy

[golunvolo]

Very delicate. I like the rendering as well

[Erik Lund]

Just to be sure; Have a look (compare with other camera) at the stop down aperture leaver of the camera, these can also be bent out of shape by inserting a lens slightly askew, I have seen several Df cameras with this damage,,,

[brent_e]

lovely image, Armando! 

[John Geerts]

Delicate image, Armando.

Just to be sure; Have a look (compare with other camera) at the stop down aperture leaver of the camera, these can also be bent out of shape by inserting a lens slightly askew, I have seen several Df cameras with this damage,,,

Ah, it´s OT here, but I noticed the same with my Df. With some lenses stopping down gives over-exposure. The lever seems to be bent a little, and moving it usually solves the problem.  Is that a job for the Nikon Service center?

[armando_m]

Just to be sure; Have a look (compare with other camera) at the stop down aperture leaver of the camera, these can also be bent out of shape by inserting a lens slightly askew, I have seen several Df cameras with this damage,,,

Erik, I'll check it out, thanks for the hint

[David H. Hartman]

It's easy enough to check the lens by activating the Aperture Stop-down Lever on the lens bayonet with your finger. If the aperture is free and active then it's something other than the lens. The most obvious as noted above is the Aperture Coupling Lever in the body.

Dave Hartman

[I suppose if the aperture stop-down lever in the lens is bent that might cause binding but with two lenses sluggish it sounds like the body. I've never seen this myself: touch silicon. This all assumes the aperture blades aren't lube contaminated which unfortunately I have seen.]