Rodenstock Rodagon-G for Large Prints

[Ian C]

Many darkroom users recommend the use of Rodenstock Rodagon-G high-magnification enlarging lenses for unusually large prints. But what you think of as “an unusually large print” might not match Rodenstock’s Rodagon-G specifications when the film size is large, such as enlarging a large-format film.

It makes sense to use the appropriate lens. In some cases, the Rodagon-G is the best choice. In others, a standard enlarging lens is the best choice. Standard lenses are cheaper and abundant. That’s important when we consider the scarcity and high prices of Rodagon-G lenses. By consulting the lens maker’s data, you can choose the most practical lens for the job.

First determine the required magnification to make the desired projection size. I’ll use the 30” x 40” print size (762 mm x 1016 mm) for the comparisons. The print’s aspect ratio is 4 x 3.

35 mm Negative: If we start with a 35 mm negative (24 mm x 36 mm), we find that the largest 4 x 3 rectangle contained in the negative is 32 mm x 24 mm. The minimum magnification required is m = 762 mm/24 mm = 31.75X.

That’s within the 15X-25X-50X magnification range cited by Rodenstock for its 2.8/50 Rodagon-G, making it a good choice.

[Note: The 40 mm f/4N EL Nikkor is designed to cover the 35 mm format and is rated for the 5X-10X-30X range. Its maximum magnification is only somewhat less than the required 31.75X and might give acceptable results. I’ve had good results using this lens for enlarging 35 mm films up to 20” x 24” print size (about 21.2X).]

https://www.galerie-photo.com/manuels/el-nikkor-enlarging-lenses.pdf

6 x 6 cm Negative: (assumed size 56 mm x 56 mm). The largest 4 x 3 rectangle contained is 56 mm x 42 mm. Minimum magnification = 762 mm/42 mm = 18.1X. This is best enlarged with the 5.6/105 Rodagon-G with its 10X-20X-40X range.

4” x 5” Negative: (95 mm x 120 mm). The largest 4 x 3 rectangle contained in the negative is 90 mm x 120. The minimum required magnification is 762 mm/90 mm = 8.5X

Though usable, this is somewhat outside of the 10X-20X-40X range of the 5.6/150 Rodagon-G. Making the required projection is within the range of 135mm and 150 mm standard enlarging lenses. For example, both the 5.6/135 and 5.6/150 Rodagon lenses are rated for the 2X-6X-10X range.

8” x 10” Negative: (245.5 mm x 318.8 mm (Lisco holder) ). The largest 4 x 3 rectangle contained is 318.8 mm x 238.5 mm. Minimum required magnification is 762 mm/238.5 mm = 3.2X.

Both the 5.6/300 and 5.6/360 Rodagon-G lenses are rated for a magnification range of 8X-20X-30X.

[Note: The recommended film size for the 240 Rodagon-G (8X-20X-30X) is 13 cm x 18 cm (5” x 7”). It’s not intended for enlarging 8” x 10” negatives.]

Thus, none of the Rodagon-G lenses are rated by Rodenstock for making a 30” x 40” print from an 8” x 10” negative. The smallest projection intended for a 300 mm or 360 mm Rodagon-G lenses is 8*(245.5 mm x 318.8 mm) = 1964 mm x 2250.4 mm (about 77” x 100”).

The proper choice for enlarging an 8” x 10” negative for a 30” x 40” print is a standard 240 mm or 300 mm lens. For example, the 5.6/240 and 5.6/300 Rodagon lenses properly cover an 8” x 10” negative and are rated for 2X-4X-8X.

If you intend to use a significantly smaller portion of the negative, then the required magnification should be based on the cropped dimensions. For example, if you plan on enlarging a 100 mm x 133 mm section of an 8” x 10” film to 30” x 40”, then the magnification is 762 mm/100 mm = 7.6X, which is within the stated range of a standard 240 mm or 300 mm enlarging lens.

Other brands of standard 6-element 4-group enlarging lenses have similar ratings for a given focal length. The page characterizing the Rodagon-G lenses in the following Rodenstock PDF file is useful. The data for each of Rodenstock’s enlarging lenses is given in the tables that follow.

http://www.prograf.ru/rodenstock/enlarging_en.html

 

[xkaes]

This is a good point. Lots of people don't need a G lens to make large prints, but much depends on what "large" is -- and the film size, as you mentioned. For 30x40" prints from 35mm (and smaller), I'll use my Rodagon-G 50mm mainly because I have it. But my large prints a often larger that 30x40". And for 4x5", I use a 150mm G-Componon, because the prints are often much larger (or longer), and 90% of the time cropped -- some severely, like panoramas.

So, as usual, it depends, but people can get great "large" prints from NON-G lenses.

 

[DREW WILEY]

Another option is to use symmetrical graphics process lenses. For example, 4-element f/9 Apo Nikkors works well over an extreme range of magnification ratios. These were preferred by some labs for mural applications. They were expensive new, but now come up for sale at very reasonable pricing and are optically superb.

Rodagon G's are specialty niche lenses. Unless you are working at high magnification ratios, they don't apply. Similarly, Rodagon D's are niche "duplicating" lenses engineered the opposite direction, for 1:1, or very small magnifications.

For 30X40's from 4x5 film, I use either an ordinary Rodagon 180 or an Apo Rodagon N 150. For 8X10, I've used 240, 305, and 360 f/9 Apo Nikkors, as well as a huge 360/5.6 El Nikkor. I never print MF shots anywhere near that big, so really have no need for a Rodagon G, despite owning or having owned kinds of enlarging lenses.

 

[Klaus Mähring]

Great post, it was time somebody corrected all those misconceptions about using the G-lenses!
About using a process lens: Aren't they built to be used with a pretty small aperture?

 

[Lachlan Young]

I'd hope it was obvious that you should only get the ones you need, and unless you are doing multi-strip enlargements the need for any of the G-lenses longer than the 150 is pretty pointless.

The 50 and 105 make a significant difference in their optimisation ranges if you have a suitably solidly assembled/ braced/ aligned enlarger and are worth the money.

About using a process lens: Aren't they built to be used with a pretty small aperture?

They were really meant for delivering a sharp and correctly shaped halftone dot across the field. The fact that the enlarger lens manufacturers could have chosen to make these pretty simple 4/4 lenses from their graphic arts catalogue (though there is at least one Kodak enlarging ektanon with a 4/4 layout) and not made the much more complex lenses that they did seems to have been rather lost on those for whom 'Apo' and 'free from the skip that contains a scrapped process camera' is about the point that their critical faculties shut down. Nevertheless, they are capable enough lenses - for the 1960s.

 

[gary mulder]

The Rodagon-G and the APO-Sironar-N are optically the same.

 

[Lachlan Young]

The Rodagon-G and the APO-Sironar-N are optically the same.

Maybe. Rodenstock's claims were that they were designed to match up for aberration correction. Given an identical set of optical elements, merely adjusting their spacing alone can have major impacts on their coverage, optimal sharpness across the field and working aperture. With an optical bench, sufficient tools/ knowledge or deep enough pockets and a skilled optical engineer, you could probably adjust one into being the other.

 

[DREW WILEY]

The premier process lenses are better "apo" corrected than seemingly any "apo" enlarging lens or camera taking lens. It isn't just a marketing ploy. This is quite evident in actual results, or even under a critical easel magnifier.

Klaus - in actual use with an even diffusion system, and "normal" or longer focal lengths per film format, f/9 4-element Apo Nikkors optimize from f/11 down - right where most f/5.6 official enlarging lenses begin to optimize. In other words, the printing aperture can be the same; it's only the maximum focus aperture that differs. Published specs for sake of the graphics industry per se tend to be standardized at f/22, but that certainly does mean that's the only aperture you can use!

I use Apo Nikkors for very critical 4X5 to 8x10 enlarged duplicate chromes or internegatives at a small magnification ratio as for big print enlargements. Placed on an 8x10 view camera, it will be one of the sharpest lenses at infinity you can find, if that is one's priority. The major local labs preferred them for true mural sized work. It was a budget choice; these were quite expensive back in their industry heyday up until the mid-80's. But these don't come in short focal lengths, leaving a distinct niche for R-G's.

R-G's and Apo Sironar N being the "same" is highly doubtful. One could try to contact Bob Salomon, the former Rodenstock Rep for the US; he'd probably shut down that hypothesis pretty hard. I've discussed G lenses with him before.

Here on the Pacific coast, 4-element Nikon lenses held a high reputation among pro print shops and for photo lab mural usage. But there was still competition from Rodenstock G's arriving from the east coast, and of course, from Goerz Trigors when those were still around. But casual copy applications, like poster and T-shirt silkscreen operations used cheaper "stat cameras" typically equipped with inexpensive Roganor lenses, or private-label equivalents. Nikon had their own line of cheaper process lenses too; but I never ran into any of those.

 

[Ian C]

Regarding the process lens question of post #4

“About using a process lens: Aren't they built to be used with a pretty small aperture?”

Per the paragraph on page 2 of the APO Nikkor PDF under the heading 3) Maximum Aperture Performance, we read,

“Generally speaking, the lens can be used as wide open as only 2-stops below the maximum aperture setting, with uniform brightness free of vignetting; in fact, it is recommended that the lenses be used in this way at all times, unless special requirements of the situation dictate further closing.”

https://www.savazzi.net/download/manuals/Apo-Nikkor.pdf

 

[Klaus Mähring]

Regarding the process lens question of post #4

“About using a process lens: Aren't they built to be used with a pretty small aperture?”

Per the paragraph on page 2 of the APO Nikkor PDF under the heading 3) Maximum Aperture Performance, we read,

“Generally speaking, the lens can be used as wide open as only 2-stops below the maximum aperture setting, with uniform brightness free of vignetting; in fact, it is recommended that the lenses be used in this way at all times, unless special requirements of the situation dictate further closing.”

https://www.savazzi.net/download/manuals/Apo-Nikkor.pdf

Thanks Ian C!
This opens up an intermediate step up for color enlargement... till I can afford an Apo El Nikkor....

 

[Lachlan Young]

till I can afford an Apo El Nikkor

Just to throw this in here: despite what people with column inches to fill might have needed people to believe, the Apo-EL-Nikkors were not the only game in town by the 1980s. Newer glass and design techniques benefited the German manufacturers too. Most of the colour separator people were mainly concerned about how 'apo' a good-enough lens was, not much more than that. If you know where to look, you can find comments from Bob Pace (who had far more practical experience of this than most who were writing hushed and reverent reviews drooling about Apo-EL's) to the effect that the 1st gen Apo-Rodagons were perfectly acceptable compared to Apo-EL's.

Very often, published lens reviews delineate what the reviewer has not tested (or had experience of), rather than what their nominal test was about. In other words, to someone who had not used a top end 240mm enlarging lens, a 240mm apo process lens might seem very high performance, especially at small (2x) enlargements. Just as an Apo-EL review probably would not have the equivalent Rodagon-G or G-Componon as comparators (though I did buy both my Rodagon-G's off someone who had had a 105 Apo-EL). Surplus Apo-EL's (going off some price lists that can be found) were often cheaper than some of then-new speciality lenses from other manufacturers (due to the rise of pre-press scanning killing off the sort of markets that had previously used Apo-EL's), so if you had the choice, you might be more inclined to go with what was then more of a known quantity. And at the same point, the classic F9.0 Apo process lenses (prevalance of which probably had more to do with which brand of process camera they were on than any tiny attempts at winnowing out small quality differences) were essentially available for taking away from process cameras going into the bin. Getting a lens of decent performance for near free will tend to distort people's ideas of what is 'good' in ways that MTF tests won't. If this isn't boring enough, you can readily run an Apo Ronar MTF off against the equivalent Rodagon (and Rodagon-G if so inclined, as well as the Rodagon-G against an Apo-Sironar-N) and see where the aims actually were, and where people's 'good-enough' thresholds might actually sit...

What I can tell you is that at their optimal enlarging ranges, a Rodagon-G delivers grain just as sharply as a regular high performance enlarging lens in the middle of their respective optimisation range. It can be very revealing about the shortcomings of various fashionable film developers of varying levels of toxicity.

 

[xkaes]

It sounds like is someone is looking for a Rodagon-G, and turned off by the price, that a G-Componon might be an alternative.

 

[DREW WILEY]

I had a chance to buy a 210 Apo El Nikkor at a reasonable price. It would have simply been over the top in terms of MTF, and had no advantage in my case except for one stop wider for focus. These are also somewhat heavy and not every enlarger will handle them without the front end deflecting. Mine certainly will. During Ciba days, you wanted as much light as you could get if printing large. I accomplished that with respect to 8x10 film by using a 360/5.6 regular El Nikkor, a huge beast which cost around $750 when I bought it new. An Apo EL 360 would have be around $11,000 and extremely difficult to find. And my set of Apo Nikkors was cannibalized for free from a giant abandoned process camera.

A major graphics supply house in SF literally tossed 24 brand new Apo El's into a dumpster when they went out of business. Those were never recovered.

Again, Lachlan seems to have some kind of built-in bias against anyone making claims about something they got for free. Well, plenty of labs and print shops elected to pay top dollar for Apo-Nikkors in the first place for a very good reason. These were even made in more than one kind of aperture - multi-bladed round apertures for optimal dot repro, adjustable square apertures for Asian character repro (or both apertures on the same lens, plus Waterhouse stop slots on all of them). Then a whole different non-symmetrical line for other purposes. Seem better corrected than Apo Ronars or Apo Artars.

Then you needed wider angle options, there were non-symmetrical G-Claron process lenses and the superb Goerz Trigors, which were based on the cemented Dagor triplet formula; these are now prized by ULF film shooters. 195 and 210 Apo El Nikkors caught on for awhile with very expensive large scanning back cameras used for high end flat art reproduction. Now those devices come with their own specialty lenses.

These lenses enjoy second lives, not only in the darkroom, but potentially as taking lenses.
A local telephoto specialist placed a 360/9 Apo Nikkor on the front end of a big Toyo G 8x10 view camera, and then at the film plane, installed either a film or digi Nikon body, or sometimes a P67 body. These outperformed any Nikon lens he had - and he was a specialty dealer for both Nikon and Celestron, who really knew his game.

I have Sinar lensboards for my Apo Nikkors from 240 to 480, and in term of apo correction and sheer image precision, outperform even my best conventional lenses like Fuji A's, GC's, and Nikkor M's. But they're a bit bulky, and frankly, overkill, especially compared to nice portable Fuji C's. For exmple, my 760 Apo Nikkor would require a no. 5 shutter and be silly heavy, whereas my 600C Fuji is quite compact and used a no.3 shutter.

 

[xkaes]

a 360/5.6 regular El Nikkor, a huge beast which cost around $750 when I bought it new.

That must have set you back for a while!

 

[DREW WILEY]

I allowed myself a 15K budget for my huge ground-up 8x10 additive enlarger. Most of it was made by myself, but obviously not lenses. If I had to make another one for sale, hypothetically, I would ask at least 75K. It gave exceptionally pure color along with serious lumen punch for sake of big Cibachrome prints, but at the expense of temperamental fancy electronics.

When the Ciba era ended, and I transitioned to RA4 printing, either directly from color negs or via internegatives from chromes, I pretty much switched over to an ordinary Durst L184 enlarger with its CMY colorhead. The spectral sensitivity of RA4 is not as idiosyncratic as Ciba, and chromogenic paper prints way way faster anyway. I still have a 5X7 true additive enlarger for smaller work, as well as for making very precise dupes, internegs, color separation negs, and various masks as needed. Apo Nikkors are especially nice for that kind of work too if enlargement is involved (versus registered contact frames).

The big beast chassis would be great if I wanted to put my 12X12 high-output cold light on it for sake of 30X40 b&w prints, or a modern 8X10 LED pancake head; but neither are likely to happen. It's getting hard enough to afford even 16X20 b&w paper. I'm now on a fixed retirement income, and getting darn lazy too. Heading for my backyard reading chair in a moment. Still nice n' cool around here, or along the shoreline. Getting hot inland, however. I'm not going to thaw any more 8x10 film until Fall travel opportunities.

 

[xkaes]

I've been down a similar path. I still have some large Ciba prints from Kodachrome 25 that still look like new. But, like you, I had to move on to color negative. I was glad when Ektar arrived -- and made sure I built a sufficient cache. Same with Agfapan 25. Fool me once, shame on you, .....

 

[DREW WILEY]

I had a running start with RA4 and chromogenic paper. I shot and printed it for "casual" portraiture. Only when Portra 160VC came out did I begin to rethink the possibility of personal work CN and RA4 style, as the demise of Ciba was already seeming inevitable. I worked with the two media parallel, and it was nice to have 160VC available in Readyload sleeves for backpacking. But it was Ektar which allowed the major quality leap into a color chrome look with a CN film.

I still have my very first Ciba print on the wall behind me, 35mm Kodachrome 25 onto an 11X14 early version Ciba. It suffered under harsh mountain sunlight for 25 yrs before I transferred it here. It's still a beautiful print, but the yellow dye component has faded somewhat. In the meantime, I made a precise 4x5 dupe from the original slide for sake of holding color saturation better when enlarged, and those second generation Ciba prints sold quickly. Too bad the lovely purpleheart frames I made for them shift under sunlight; but I always advised buyers to protect them from UV, and a more black shifted frame works decently anyway, for that particular image. The main problem with purpleheart is that if you don't keep it moving consistently along the carbide tooling, you'll get a burn mark, just like with maple or figured cherry.

All my 30X40 prints have been enlarged from either 8X10 or 4X5 color sheet film, onto Ciba, Fuji Super C, or Fuji Supergloss. The last round, I did some intermediate sized ones too (24X30). But Ektar holds detail so well that I can get decent 20X24's from 6X9 or even 6X7 originals. When it comes to b&w film, only with Efke 25 would I hazard a 20X24 print from a 6X9 shot.
I expect those MF enlargements to hold up well when viewed right alongside large format work. Guess I'm not a good candidate for actual mural sized presentation. I like to invite people nose-up to the print, with reading glasses on.

 

[Lachlan Young]

to have some kind of built-in bias against anyone making claims about something they got for free.

No, I've been the beneficiary of people clearing out some remarkably good lenses too. It's just that I'm also not inclined (from experience) to try and make the claim that lenses used outside their optimisation range or purpose are somehow more exceptional than those that were purpose designed for it. Up to 4-5x, there's no question that an Apo-Process dialyte is going to do a an excellent job (if it covers) but not necessarily better than the equivalent enlarging lens (and the latter may hit optimisation long before the dialyte has left wide-open). What we're talking about here are lenses meant for far greater scales of enlargement, not the 8x10 equivalent of postcard prints.

These were even made in more than one kind of aperture - multi-bladed round apertures for optimal dot repro, adjustable square apertures for Asian character repro

The different aperture shapes were not unique to Nikon, nor were they for east asian characters alone. Once you know a little bit about halftone graphic arts processes, their relevance becomes more obvious. But that's beside the point here.

by using a 360/5.6 regular El Nikkor,

It's a fairly ridiculously sized lens (and from my recollection of it, quite a bit bigger in terms of mount dimensions than the equivalent Componon 360 or Rodagon-G 300/ Rodagon 360), and one of the few cases where, if you don't need the little bit of extra speed, an f9.0 dialyte apo-process will do as good a job for an equivalent (fairly small) enlargement. Most of the 360/5.6 regular enlarging lenses were 2.5x optimised or thereabouts.

 

[DREW WILEY]

Yes, the 360/5.6 El Nikkor is huge, and I stated my reason for once owning one, which did involve both focussing issues in reference to heavily masked chromes (up to .90 density masks), and the potentially long printing times of Cibachrome. So having that wider aperture proved valuable. But that also involved a massively solid enlarger with a completely custom lens mount largely dedicated to big Ciba printing.

But for current RA4 printing, as well as black and white work, my various f/9 Apo Nikkors are nice and petite, and will fit in ordinary Durst L138 and L184 turrets, and are optically superb to boot. And since I'm talking about 8X10 and 4X5 film enlarged no bigger than 30X40 inches, that's a modest magnification range. It's not like enlarging 35mm film that big.

I mentioned all this simply to indicate how the term "mural size" has very different lens connotations relative to film format. Even a 40X60 inch print doesn't amount to very much actual magnification if the original is on 8x10 film. In that kind of instance, a Rodagon G would have no advantage at all, perhaps even a liability.

The 360/5.6 El Nikkor was optimized at 4X, but for all practical purposes, you'd hardly notice the difference at 6X. The Apo Nikkor 360/9 as well as Apo El Nikkor were recommended up to 10X, and that's with reference to technical applications much more stringent and specific than general photo applications; so these would have been more than ample for even true mural sized work if sheet film were involved.

From actual tests of equivalent focal lengths, my Apo Nikkors outperformed all my regular enlarging lenses at f/11; and I'm factoring some late top end enlarging lenses, including Apo Rodagon N's. Of course, at a certain point, this all becomes darkroom overkill. A notable exception would be enlarged color dupes and internegs, which will in turn be enlarged, warranting one's best lenses.