Noctilux Focussing Problems

Phil_Hawkes said:
I took my Nocti in for repairs, and I was showing my R-D1 to the guys there. They noticed that the rangefinder was now not meeting at infinity for some lenses. It was particularly off for the Konica Hexanon 50mm. With some lenses the images seemed to meet. As a result, the R-D1 is visiting another technician to get the alightnment checked again.

Phil
Click to expand...

I have the R-D1 back (again). The Nocti was also in serious need of repair. Now both are fixed I am getting very accurate focussing... not only with the Nocti, but also with the Konica Hexanon 50/2 that was also being a problem. See THIS THREAD for some examples with Konica lenses.

The interesting photos that I have with the Nocti are photos of people, and I am still waiting for their permission to put the photos up. I took some super-low light photos of nocturnal creatures at the zoo the other day. I'll try to get some of those photos up later.

I have found that the Nocti seems to misbehave a little for the first few shots after attatching to the body. It seems to behave if I wiggle the lens in the mount a bit, and rotate the focus between infinity and 1m a few times... It seems to ensure that the focus follow wheel is accurately aligned. That is my impression anyway.

Phil
 
Example photo of my sister using the Nocti at f1.0 or f1.2. RAW processed in Pixmantec RawSheetoer to TIFF and then used photoshop to transform (without alteration) to JPEG. Perhaps not the best example, but the only person I have permission from to post images :D Phil
 
Phil_Hawkes said:
I think my Noctilux is focussing incorrectly when open to 1.2 and 1.0. It seems to focus just behind what I am focussing on. I haven't done a ruler test, but I do have (frustrating) experiences from the field. If I take my time and the object is static, then I have more success. The strange thing is that the focus seems fine at smaller apertures. I am sure that it is not just a depth of field issue.

I seem to remember someone commenting that the focus can change with aperture. Does anyone know if this applies to the Noctilux?

Has anyone else had this experience or is it just me?

I keep meaning to get my R-D1 calibrated to makes sure the camera isn't the problem. The lens may also need looking at. One of these days I'll get around to it.

Cheers,
Phil
Click to expand...


Hi Phil:

Several months ago I was loaned a Noctilux 1.0 and I used it on an RD-1. I was warned that the base length of the RD-1 was not quite long enough for accurate focusing of this lense. I paid little heed to the insight but when I started to take pictures with it, I indeed found that the pictures were slightly out of focus even though I saw a focussed image in the viewfinder.

I was still so impressed with the ethereal quality of the Nocti that I purchased it at the same time that i purchased my first Leica M camera .......... yes......the M8. Works more consistently on the M8.

When I first brought this new equipment home, I found also that the Nocti was focusing a hair just beyond the point that I was focussing on. Took the Nocti and M8 to the dealer and they found that the M8 required a rangefinder adjustment. It has been pretty consistent since then.

The only time I find that the focus is out is in extremely low light when my eyesight is too arrogant to admit that I'm not sure of the focus. (That remark is strictly about ME).

Hope this helps.
 
there is a play in R-D1, where when you turn the focus knob of the lens, the rangerfinder patch would remain stationary. notilux is a bit tricky to focus even on M, let alone Bessa.
 
LCT said:
According to the formula b' = (e * f^2) / (k * z) where b' is the effective base length, e the visual acuity (0.0003 at approx. 1 arcmin), f the focal length, k the aperture and z the circle of confusion (0.020mm), the baselength of the R-D1's RF (38.2mm) is long enough in theory as a 50/1 lens needs 37.50mm to be focused accurately.
Now if the actual focal length of the lens is 52mm for instance, the minimum baselength ot the rangefinder shoud be 40.56mm for the same purpose.
This problem as well as the QC issues of the R-D1 can explain some focusing problems with the Noctilux but also the Summilux 50 at f/1.4 sometimes.
Best,
LCT
Click to expand...

Lets not forget about the backlash in the R-D1 rangefinder. We're talking about several factors that effect focusing. If the rangefinder adjustments are perfect, the lens collimated properly, there is still slop in the mechanical linkage. I get a different focus point, with the 135/f4 if I focus from far or from near.
 
jim_buchanan said:
...If the rangefinder adjustments are perfect, the lens collimated properly, there is still slop in the mechanical linkage...
Click to expand...
Kind of you to quote that old post of mine. :)
Since then i've adjusted the slight vertical misaligment of my R-D1 and my success rate at 50mm f/1.4 has become roughly the same as with 0.72x M cameras.
Slop in mechanical linkage? You're right perhaps but i did not notice it with my M lenses so far.
I don't own a Noctilux though.
 
You must log in or register to reply here.
Back
Top Bottom