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View Full Version : Ronar CL 300 cover 8x10?



Robert_5479
10-Oct-2005, 11:23
I just bought a Rodenstock APO Ronar-CL 300mm and was told by the seller that it has plenty of coverage with movements for 8x10. I'm starting to have my doubts since I came across some info on a site stating the lens has only 40 degrees of coverage. I haven't recieved the lens yet, so I can't test it. The serial number is 10,591,012 and it's in a barrel. Does anyone have experience with this lens or have specs?

Thanks, Robert

Armin Seeholzer
10-Oct-2005, 11:52
Hi Robert

Sorry but it will not cover at infinity it has a coverage 264 mm 48°as stated in the Rodenstock brochure!
It will cover at around 1:3 to 1:1 wich was the main porpuse of the lens!

Sorry I use it on my 4x5!

David G. Gagnon
10-Oct-2005, 14:07
Robert,

If you bought the lens from Andrew Glover, aka Dagor77 ......

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=15248&item=7551243221

there will be no worries.

If you bought it elsewhere, read his description of the coverage. His feedback speaks for itself, as do his great item descriptions.

DG

Bob Salomon
10-Oct-2005, 14:35
The 300 Ronor is a lens designed for 1:1 reproduction at f22 and, as such, covers 8x10. It will not cover 8x10 at infinity. The CL indicates that it has a linearized aperture scale. The CL was not made in shutter and yours was made in 1984,

Robert_5479
10-Oct-2005, 15:19
How does a linearized aperture scale differ from a non-linearized...(What is it?). Yes I did get it from Andrew and intend to use it for closeup work, so it should work fine. Thanks for all your answers!

Robert

David G. Gagnon
10-Oct-2005, 16:06
"The 300 Ronor is a lens designed for 1:1 reproduction at f22 and, as such, covers 8x10. It will not cover 8x10 at infinity"

Gee...........that's strange..............I just put mine on my Deardorff to verify coverage......8x10 plus movement. Maybe "real world" is different than spec sheets.

DG

Bob Salomon
10-Oct-2005, 17:10
The linearized scale means that each marked aperature is equally spaced on the aperature ring.
On the regular Apo Ronar the marked aperaturs are not equally spaced on the ring.

CP Goerz
10-Oct-2005, 22:52
There are those who only read manufacturers spec sheets and those who read the groundglass. When the lens arrives pop it on your 8x10 and post what happens here for all to see. You will be more than happy with it as its an excellent lens.

All the best,

CP Goerz(AKA Dagor77).

Bob Salomon
11-Oct-2005, 07:51
The 300 Ronaar did not and does not cover 810 at infinity per Rodenstock.

Yes some may use the lens as a general purpose lens at infinity but they quality beyond 57" + 40mm of rise and 32mm of shift in landscape format is simply beyond the circle of acceptable definition of Rodenstock.

If you have things that are not very detailed and important at infinity, beyond the area noted above, the lens will illuminate it. But it won't equal the performance in the 5x7" +40 and 32mm area.

Yes you can also attempt to stop down beyond the design aperture of f22 but that will put you in diffraction and degrade the acceptable area while expanding the coverage.

A lens made to cover 48° at 1:1 with a 264mm circle of illumination at f22 simply won't be the equal of 70, 72, 75 or 80° lenses at infinity.

N Dhananjay
11-Oct-2005, 08:27
In general, there seems to be considerable difference between the claimed coverage of the dialyte designs (Artars, Ronars, El-Nikkors) and what one actually gets in the field - happily, actual performance seems to be better. I have heard that the claimed coverage (usually around 45 degrees) is the region in which the APO correction holds. Keep in mind that these lenses were designed for copy/repro work where the APO correction was fairly critical. In using them as general purpose long landscape lenses, people appear to get considerably more coverage. Maybe they are using the non-APO part of the image but it still seems sharp enough for practical work. Also, from a practical point of view, stopping down beyond f/22 is fairly common in certain kinds of photography - yes, one is diffraction limited but the diffraction limited performance still appears to be more than adequate for such needs. Cheers, DJ