150 Symmar convertablegreenspun.com : LUSENET : Large format photography : One Thread
I did well with my last question on my MPP flat bed I now would like to hear from any users of the 150/265 Symmar. I realise in the 265 mode it will be fairly average but what comment do people have and what have you used them for.
What is the best f-stop for the 150 and what will the 265 perform best at.
-- Steve Nicholls (email@example.com), November 25, 1999
Haven't used the 150/265 convertible. Have used the 210/375. In general, convertibles are quite adequate when used unconverted i.e., with both cells. When you use them converted i.e., with only the rear element, you lose the benefit of some of the corrections built into the design. Using a strongly monochromatic filter helps (but is limited to B&W). The loss of correction might even suit some subjects. If you're a sharpness freak, there are probably better options. Convertibles might be a good option if you're looking to keep weight down etc. DJ
-- N Dhananjay (firstname.lastname@example.org), November 26, 1999.
I love the convertable Symmars, as well as Goertz Dagors. But BEWARE there may be a significant focus shift on stopping down while using a single element of the lens. Good luck and enjoy. Mitch
-- Bill Mitchell (email@example.com), November 26, 1999.
To expand on the other postings, use an orange filter, behind the lens to correct for the removal of the front element. Focus with the filter in place and the lens stopped to the aperture that you will use to make the exposure. This allows you compensate for the focus shift that occours when using the lens, with filter, in teh converted state. You will find that the focus shift depends upon the f-stop selected and may not be very noticeable at all.
As far as the "best" f-stop, I haven't really determined it, I don't make enlargements much bigger than 8X10, so the optimum f-stop may not be as critical for me. One caveat, be sure to use the CORRECT aperture scale. Very disappointing to find that you used the 150mm scale for a 265mm shot!
-- Marv (firstname.lastname@example.org), November 26, 1999.
Didn't know where to put this information so I guess I'll add it to this thread. Just for fun, I tried out my 1953 Schneider 150/265 convertable against my Schneider APO Symar in the same focal length. I use the less pricey lenses when I'm traveling and can't keep an eye on my stuff. I put the front page of the paper on a fence in the sun. I used the same apertures (f:16)and shutter speeds and from 15 feet or so away took a picture of the paper with both. The paper was small on the 4X5 negative, less than 1" wide. Then I made huge enlargements of 1/4 of the front page of the paper to compare sharpness. If printed full frame, I'd be making prints over 72" wide. You can read the name of the paper (big) you can read the date (much smaller) you can read Washington DC in caps at the beginning of a story but can't quite read the small print in the story, some words you can make out even in the normal print of a news story. The difference between the two is so slight (I think I can see it) that I give the nod to the newer lens and my daughter and wife think the older one is sharper. The difference, if any, is very subtle. It was already my impression that in normal sized prints (for me 11X14 and smaller, an occasional 16X20)there wasn't a meaningful difference in sharpness. The older lens is a Linhof select one, so it might perform better than average. It does have a little tiny snowflake looking shiney spot in it, which I think is a tiny bit of separation. If you are starting out in large format and want to save money, I think these lenses are a bargain. The 180/315 I have is terrific. I only shoot b&w, so if there is some big advantage with the newer lenses and color film, I don't have the experience to know.
-- Kevin Crisp (KRCrisp@aol.com), May 13, 2001.