focusing a Jupiter-11 on a CLE possible?

[fer_fdi]

I have a 1960 KMZ 135/4 Jupiter-11 which is clean, sharp from f4 and renders very nicely.
I use it on APS-C and like it a lot.

What would be my chances to focus with decent accuracy at f4 on a CLE?
Maybe not at min focus distance but at, say, 5 meters?

if there's no way, tell me gently please, I will get very upset 😛

 

[fer_fdi]

any help appreciated

Would it be much different on a IIIc ? (135mm viewfinder apart)

 

[Palaeoboy]

Unfortunately even at 5 meters it will still be a bit of hit and miss. I use a 135mm f4 Tele-Elmar on my CLEs but pretty much only from 10 metres and upwards and most of the time just at infinity. I take the view that use of a 135 tele lens is only warranted when the subject is at a much greater than average distance. I try to use a 90mm which can focus accurately and only resort to the 135 if im unable to get closer with the 90.

You will also find framing accuracy can be a bit of a problem also. Most of the external 135mm finders are made for Leica/Canon Rangefinder cameras which have a staggered shoe which is not directly above the lens mount like the CLE. As such when you use these finders the image is skewed to one side and ruins any hope for decent framing. In your case the best M mount choice would be 28/90mm to bring up the 90mm frame so you can get the image roughly centred although not that accurate given how tiny and insignificant they are on a CLE. My Tele-Elmar with its 35/135 mount doesnt bring up any framelines just the 28mm one that is always visible so you have a slight advantage being able to choose the option of a 90mm mount.

So yes its doable but I must admit I get an equal amount of failures to successes. On digital cameras this may be perfectly acceptable simply take another or long sequence but on a film camera like the CLE it can get expensive and disheartening. I suggest use a 135 as a last resort policy only when its beyond a 90mm lens to get a good shot. And more likely than not because there isnt that guarantee of success for most of your shots it will deter you from making the 135 as a carry-all lens that weighs a reasonable amount like those Jupiters do.

Sorry I couldnt be more positive.

 

[David Hughes]

OTOH, you could use a tape measure, a lot of us used to a long time ago...

Regards, David

 

[splitimageview]

RF accuracy chart


Unfortunately it's iffy at best.

Choose percentage or OK/Not OK via the buttons at bottom left.

 

[fer_fdi]

Thank you very much to all for your valuable help.
I'll do my best and test it when I finally get the camera.
Love how this lens draw (on digital, so far : )

I see (on the chart) the EBL of the IIIc is notably larger than on the CLE...
I'll try to use it on my brother's IIIc (inherited from my grandfather : ) but I cross fingers about coupling (Jupiter-11/IIIc matching)


BTW, how I have to read that chart? Is the % the average focusing error?

 

[splitimageview]

Any figure under 100% is within the capability of the camera (and/or camera + magnifier combination) to provide accurate focus for a given focal length.

 

[fer_fdi]

all right, thank you very much

btw, a million thanks to the chart's author
this is a brilliant community