19" Artar ULF Coverage

After many kind recommendations on suitable lenses for the 12x20,

I'm wondering if anyone has any insights as to what the usable image

circle is with the 19" Red Dot Artar at f/9(for composition and

focusing) and if there is a difference between the older APO Artar

and the newer Red Dot Artar in regards to focus shift when stopping

down and if either version has greater or less coverage than the

other. I'm under the impression that the Red Dot was simply a

factory coated version of the APO Artar, but since I can't do a side

by side comparison, I thought I'd beg your collective advice!---

Thanks!

The 19" Artar will cover 8x20. Artars were originally optimized for 1:1 distances, and were uncoated. Red dot Artars were coated and some of them were supplied in shutter and these were supposedly optimised for 1:10 distances. The Artar is a symmetrical dialyte design and consists of 4 air spaced elements, so the coating really does help. The Artars, unlike the Dagors, don't suffer from focus shift. Focus shift is due to zonal spherical abberations (Dagors are quite notorious for suffering from this). Artars are very well corrected and very sharp lenses. Also, the corrections are quite stable over a wide range of distances, which means they can be used quite well at infinty distances. Cheers, DJ

Just to confirm what was said above: the 19 inch Artar will not cover 12X20. I believe the shortest FL in this design that covers is 24 inches (though I would get a Fuji f11.5 C if I were looking for this length in a ULF lens). I have a 30 inch RD Artar for 12X20, and have been very satisfied with it, mounted by the late S Grimes in a Copal 3 (at the expense of half a stop of speed wide open).

 

Good luck,

Nathan

There is also a "newer" Apo Artar manufactured by Schneider through the late 1980's

or early 1990's. AFAIK all were coated and a few of the lastest were multicoated

(although I have never seen one of these).

OK, now I'm confused! Dhananjay says the 19" will, Nathan says the 19" won't---both people whose opinions and experience I hold in high esteem. My 19" APO Artar seems to cover ok, though I haven't yet 'put it through the wringer' as far as movements go and the film won't get here for another week or ten days for a real shoot. If the 19" is my panacea, I don't think the expense of putting it in a shutter would be justified unless I found a red dot(coated)version, but I still don't know if there are any other differences between the two versions, except that the Schneider-made Artars wouldn't have the coverage(right?) For the price, the 355 G-Claron and 480 Nikkor M seem light more than viable options---particularly if the Ebay muse are smiling. Rather than submitting a new post, does anyone have any practical experience with either of these lenses aboard the 12x20? Will either of them cover 12x20 at f/9? Thanks!

Coverage can have a different standard with ULF work where the print is usually made by contact printing rather than projection.

 

The circle of illumination of the 19" Red Dot Artar is more than enough to cover the format, but even when stopped down to f/45 the image is a little soft at the corners. Probably good enough for contact printing, depending on your criteria. You can work around the softness with some subjects by placing are areas where detail does not matter very, such as sky, clouds, etc. on the corners.

 

Sandy King

I'm sorry - that was confusing. I was saying that it would certainly cover 8x20, but might be marginal on 12x20. Although here I agree with Sandy. Demands on enlarging versus contacting, and just what is considered good performance in the corners, differs from one person to the next. Also, it should be kept in mind that the specs of these lenses are typically quoted for graphic arts purposes where they have, well, somewhat higher criteria than a 'contact print landscape' kind of person would. The Artar does not deteriorate too much through its circle of illumination. The Dagors and related designs (such as the Angulon) have large circles of illumination but performance at the edges can be pretty poor, unless one stops well down - it is considered good practice these days to employ mechanical vignetting before the performance gets too poor (which is something of an arbitrary criterion, I guess). But this is the reason folks talk about the usable image circle of Dagors increasing as you stop down - the performance gets better way out in the circle as you stop down. The Artars don't really behave this way, so I would suspect what we are seeing are small variations and small differences in what is considered acceptable performance. Keep in mind that the difference between an 8x20 and 12x20 is not too huge, a couple of inches or so, fairly trivial for a 19" lens - we're talking about probably a difference of about one or two degrees in terms of coverage. So, regardless of what anyone else says, if it works on the 12x20 for your purposes, that is really all that matters (especially since you are probably contact printing that). After all, many folks report happily using the 12" (and even the 10 3/4", though I think that might be pushing it) on 8x10. Cheers, DJ

John asked about coverage of the 355mm G-Claron and the 480mm Nikkor-M (I assume he meant the 450mm Nikkor-M, right?) with 12X20. I use both of these lenses. The 355 G-Claron covers sharply all the way to the corners stopped down to about f/45, but gives less than an inch of movement. The 450mm Nikkor-M has really huge coverage and is plenty sharp all the way to the corners even when used with four to five inches of movement on 12X20.

 

Personaly I consider the 450mm Nikkor-M the number one best overall lens for the 12X20 format. Sharp, relatively small, multi-coated, huge coverage, and still quite wide-angle for the format. At a going price of $700-900 it is much less expensive than a late model coated 16 1/2" Dagor, which will seet you back from $1500-$2000, but given the choice of the two the Nikkor wins hands down in my opinion.

 

 

Sandy King

Thanks! What a wonderful resource this forum is! I checked the archeives for info on the 450 M as well as the 19" Artar and I think I'll use the 19" in the barrel until I can save enough money for the Nikkor(or at least until my family forgets how much I spent on the 12x20!) Thanks!