RF accuracy chart

[LCT]

...from practical experience, I have a higher hit rate with the RD1s (new) at 75/1.4 and 2.0 which are *RED*, than with CLA'd M6 .72 with Noct 1, and CLA'd CL with 40/f2 which should be *OK* Maybe the Canadian 75's used .03 for coc??...

Indeed it is not normal at all. At f/1.4 your 75 is way out of the accuracy range of the Epson. It is even very difficult to focus on the M8. Also, the .72x M6 has a longer EBL than the R-D1 (w/o magnifier) and the 40/2 should not have any problem with your CL at any aperture IMHO. Did you have the 40/2 cla'd as well?

 

[MikeL]

Indeed it is not normal at all. At f/1.4 your 75 is way out of the accuracy range of the Epson. It is even very difficult to focus on the M8. Also, the .72x M6 has a longer EBL than the R-D1 (w/o magnifier) and the 40/2 should not have any problem with your CL at any aperture IMHO. Did you have the 40/2 cla'd as well?

Ted, are you framing your subjects for the 75mm like you would with the 50mm? (i.e. farther away from your subjects with the 75mm)

 

[ferider]

Not that I don't want an SP ....

I am keeping this chart updated as we add stuff ...

 

[BillBingham2]

Can you take the 135 up to 3.5 and 2.8 please?

Thanks.

B2 (;->

 

[Anupam]

I thought the rule of thumb was the EBL should be equal to or greater than the physical diaphragm opening for the aperture. Given that, one would need at least a 50mm EBL to focus the Noctilux. I wouldn't bet on reliably focusing the Noctilux consistently with the 25mm-ish EBLs of the R and R2. Anyone been doing that regularly?

 

[ferider]

Can you take the 135 up to 3.5 and 2.8 please?

Thanks.

B2 (;->

Just updated the above picture and emailed you the sheet.

Cheers,

Roland.

 

[splitimageview]

Roland, for completeness you might want to add the 105/2.5. 🙂

 

[ferider]

I thought the rule of thumb was the EBL should be equal to or greater than the physical diaphragm opening for the aperture. Given that, one would need at least a 50mm EBL to focus the Noctilux. I wouldn't bet on reliably focusing the Noctilux consistently with the 25mm-ish EBLs of the R and R2. Anyone been doing that regularly?

Not the 50/1, but I have reliably used the 50/1.2 on the R2, Anupam.

Note that the above table does not account for minimum focus. For example, the 135/2.8 focuses down to 1.5m (? out of memory), the Leica 50/1 to 1m, and the newest Leica 50/1.4 to .7m, which makes the 50/1.4 practically as hard to focus as the 50/1. The worst lens to focus, IMO, is the 75/1.4 at .7m ....

Roland, for completeness you might want to add the 105/2.5. 🙂

I'll let it sit for a while, maybe we get some more requests ....
How is "my" 105 doing, BTW ? 🙂

 

[John Noble]

While we're having fun, here's a universal graph based on a .030 CoC. It's just a quick grab out of Apple's Grapher utility.

The Y axis is required EBL, and the X axis is aperture. The 35, 50, 75, 90, and 135 focal length curves are labeled.

No warranty express or implied. 🙂

 

[BillBingham2]

Roland,

This would be a great tool for a Marketing person to use to figure out what is the right length for a particular mix of lenses. Not that there would ever be that big a market again, but it's very cool.

Thank you Sir!

B2 (;->

 

[splitimageview]

I'll let it sit for a while, maybe we get some more requests ....
How is "my" 105 doing, BTW ? 🙂

How 'bout a request for 43mm Pentax? Although any focal length under 50 is a not an issue...

*Your* 105 is doing great. Hey, come to think of it, I also bought one from Bill (F mount.)

 

[Roberto]

...
Would be interesting to see if this table corresponds to other users experiences, I'd guess not, or who in their right mind would use a Bessa or CL??!!
...

Well..
I have a Bessa R and I have never been able to focus correctly the Jupiter 9 at f2, it start looking OK at f4.

I know it may be because it is Russian but in my opinion the J9 myth has born because of the short rangefinder base of many cameras out there like the Bessa..
R.

 

[Roberto]

Just updated the above picture and emailed you the sheet.

Cheers,

Roland.

Would you be so kind to post it somewhere on the net? 😱

 

[ferider]

I can only post pictures on my smugmug account, but maybe somebody else
can host it ?

 

[BillBingham2]

Beware

Beware

How 'bout a request for 43mm Pentax? Although any focal length under 50 is a not an issue...

*Your* 105 is doing great. Hey, come to think of it, I also bought one from Bill (F mount.)

It is an addictive lens. Beware.

I use to make fun of people having so many 50mm lenses, then I looked at the fact that I had four 105/2.5 (S, LTM, F and F AIs (ok the last one a lens I gave my wife years back that I now have)) and two CV 25/4 (S and LTM).

BTW, John asked me for your address so I think this is a fast turn around from him. A good sign.

B2 (;->

 

[BillBingham2]

Well......

Well......

I know it may be because it is Russian but in my opinion the J9 myth has born because of the short rangefinder base of many cameras out there like the Bessa..
R.

No, there's a lot of truth to it. I had a J9 on my Bessa T, my Leica M6 and M4-P testing it and it was off. Have a number of folks around the world with similar issues (the focus being off of dead on a couple to four inches). Went to a Nikkor 85/2, SPOT ON with every camera.

B2 (;->

 

[splitimageview]

Yes, this will be my third (F, S, LTM)

I emailed John...thanks for the heads up.

Roland, I can host...

 

[John Noble]

OK, here's a new chart with limit lines for common bodies.

[edit: updated the chart for better readability]

 

[ferider]

No, there's a lot of truth to it. I had a J9 on my Bessa T, my Leica M6 and M4-P testing it and it was off. Have a number of folks around the world with similar issues (the focus being off of dead on a couple to four inches). Went to a Nikkor 85/2, SPOT ON with every camera.

B2 (;->

This is me focusing an N 85/2 on a friend's RD1 (no magnifier) -- and failing miserably. I've tried on R3 and R2 with no success. 😡

Photo by Robert 🙂

Roland.

 

[BillBingham2]

The RD1 and R2 does not surprise me, the R3 does, but everyone has off days.

B2 (;->