APO - Rodagon - N 150mm - as a taking lens

[Doppler9000]

Wondering if there are any options to replace the stock aperture with either a shutter or aperture unit with more, perhaps rounded blades.

My research indicates the Componons are probably better candidates.

[Greg]

Years ago I had wanted to do the same with my Componon-S. It has 5 blades. Two repair shops told me that it couldn't be done. One said that they could do it but the price quote was north of $500.00 as best I can remember. Opted to acquire an EL NIKKOR (older all heavy duty metal construction) with its many blades and thus nearly circular aperture opening for a lot less money. Ended up actually subjectively preferring the projected image of the EL NIKKOR to the Componon-S. Ended up acquiring three other older heavy duty metal EL NIKKORS of different focal lengths.

[xkaes]

I have no idea if it makes a difference in enlarging, but I've had the option for a couple of Componons between the older versions (13 blades?) and the newer ones -- larger & with more features, for sure, but FIVE blades. I chose the older lenses each time. I assume that Schneider thinks there is no difference. I never compared them, so I can't say.

[Doremus Scudder]

I'm trying to understand why the number of aperture blades in an enlarging lens would make any difference at all in the final enlarged print. The number of blades does have an effect on out-of-focus rendering (bokeh) when photographing 3D subjects, but it will make zero difference in a totally in-focus print. Unless you're intentionally making part of your print out of focus or using the enlarging lens as a taking lens, I don't see the point. Care to enlighten me?

Best,

Doremus

[ic-racer]

If the aperture is not round, sometimes this can be an easy fix. It is not that unusual for a blade to jump out of its slot or hole. In which case disassembly with reassembly in the correct order can fix the problem.

[xkaes]

The 5-blade apertures being discussed are definitely not round. They have straight edges on each side. The older models with a dozen or so blades are very close to round. I assume, like Doremus, that it makes no difference in prints, and I also assume that's why they made the switch to fewer blades. What not four or three? I have no idea, but I do have Rodenstock enlarging lenses with only three blades -- and they work fine.

[Doppler9000]

I'm trying to understand why the number of aperture blades in an enlarging lens would make any difference at all in the final enlarged print. The number of blades does have an effect on out-of-focus rendering (bokeh) when photographing 3D subjects, but it will make zero difference in a totally in-focus print. Unless you're intentionally making part of your print out of focus or using the enlarging lens as a taking lens, I don't see the point. Care to enlighten me?

Best,

Doremus
I am thinking of using it as a taking lens, which Rodenstock approves of, for at least some of their enlarging lenses.

[Drew Wiley]

Well, given the thread heading, why would you want to alter a rather hard to find, expensive, top-of-the-line 'Apo N" 150?

[Doppler9000]

Well, given the thread heading, why would you want to alter a rather hard to find, expensive, top-of-the-line 'Apo N" 150?

Because it’s a nice lens with bad bokeh?

[xkaes]

Because it’s a nice lens with bad bokeh?

It might, but you can get a 150mm APO taking lens for 1/4 what that Rodagon can get you.

[Oren Grad]

I've moved the thread and re-titled it to better match what the discussion topic actually is.

[Oren Grad]

Because it’s a nice lens with bad bokeh?

Changing the iris shape won't fix a lens with "bad bokeh", unless by that you mean solely the shape of specular highlights. The optical design is a more important determinant of the overall smoothness or harshness of rendering.

[Drew Wiley]

Simply switching the aperture to fully round with many blades won't necessarily provide good "bokeh". It has a lot to do with the lens elements too. For example, all my Apo Nikkor process lenses which I ordinarily use for enlarging have multi-bladed apertures, and are better optically corrected than any regular enlarging lens, better even than Apo R. N's, and also perform better at very close range. But they do excellent at infinity too, so I have Sinar boards for them, for sake regular LF photo usage - They're Amazingly sharp and apo corrected, BUT with miserably busy unpleasant bokeh.

On the other hand, I have an old single-coated f/9 Zeiss mfg 360mm tessar-style process lens which I bought dirt cheap, which has wonderful bokeh as well as excellent optical performance, even on 8x10 format.

[Doppler9000]

Yes, I understand that the iris affects only some components of the OOF rendering.

It’s a question of sufficiency versus necessity. Not every lens with a round iris has pleasant bokeh, but I am not aware of many lenses with pentagonal irises with appealing bokeh.

[Doppler9000]

It might, but you can get a 150mm APO taking lens for 1/4 what that Rodagon can get you.

What would you put on the short list, in the same weight and quality range of the Rodenstock?

[Doppler9000]

I've moved the thread and re-titled it to better match what the discussion topic actually is.

Thanks.

[Dan Fromm]

What would you put on the short list, in the same weight and quality range of the Rodenstock?

Well, if you need a lens that will cover 4x5 at infinity, the 150/9 G-Claron might do for you. The cells are direct fits in a #0 shutter.

If you don't need that much coverage because you intend to work close up, the 150/9 Apo Ronar might suit. IIRC, newer ones' cells will also fit a #0. My older one's cells won't fit any known shutter, I use it mounted in front of a #1.

[Doppler9000]

Well, if you need a lens that will cover 4x5 at infinity, the 150/9 G-Claron might do for you. The cells are direct fits in a #0 shutter.

If you don't need that much coverage because you intend to work close up, the 150/9 Apo Ronar might suit. IIRC, newer ones' cells will also fit a #0. My older one's cells won't fit any known shutter, I use it mounted in front of a #1.

Thanks, Dan.

By the way, I appreciate the articles you’ve written that are posted on www.galerie-photo.com. I lust after process lenses after I reread the Nikkor article, which is overly frequently.

[Lachlan 717]

The speed of the Apo Rodagon was part of the appeal, as well.

Look at Tessar designs. They might also satiate your Bokah requirements.

[xkaes]

Other Bokehphiles can chime in, but I'd question whether APO "improves" bokeh at all. And if it doesn't, you can save even more money with a 150mm taking lens.

[Drew Wiley]

A couple of questions: Is this for sake of 4x5 photography, and why is only 150mm being considered? Even a 150/4.5 Apo R N needs to be closed down one or two stops for ideal performance, especially in relation to luminance falloff. You might be better off taking a thick-element tessar like the Fuji L 210/5.6 and shooting it at f/8. Another factor: enlarging lenses aren't necessarily designed with an oversized image circle for sake of view camera movements.

A enlarging style which was cross marketed for tabletop LF photography was the old Componon series, with the 135/5.6 being the most common example marketed in shutter. Or you could remount any number of lenses into a large multi-bladed old Copal 3S shutter, at extra expense, of course.

Many process lenses came with a slot to allow optional Waterhouse stops, including various round diameters. But process lenses rarely occur in focal length less than 180mm, and typically have f/9 max apertures for sake of optimal correction.

Regardless, bokeh is accentuated at shallower depths of field - another reason to consider longer than "normal" focal lengths.
A 300 mm lens at f/11 will have the same depth of field as a 150mm lens at f/5.6, but with significantly more even illumination and edge correction, since you'd being using only the center of the element for 4X5 format. Some process lenses will perform way better at f/9, nearly wide open, than enlarging lenses will at 5.6, and certainly way better than typical taking lenses wide open.

The gist of the problem is that one often doesn't know exactly what kind of bokeh they want until they've tested various options.
And even on a specialized forum like this one, it might be difficult to get ideal feedback unless you spell out you own anticipated project needs more specifically.

[Doppler9000]

Thanks, Drew.

This is for a medium format camera.

I think l’ll pick up a dual-use Componon to test the concept and learn more.

[Drew Wiley]

Oh - with MF, you'd have a ton of wiggle room with a 150. I have never tested my 150/4.5 Apo N as a taking lens, or in relation to bokeh. But I have used it wide open at f/4.5 for enlarging MF negs on slow Azo contact printing paper with superb results. In fact, I normally enlarge 6x7 and 6x9 negs with this lens rather than the shorter 105 Apo N, since there is no illumination falloff involved with the longer lens, although my enlarger heads are just too bright for wider stops to be realistic on ordinary silver paper or RA4 color paper. I also can't answer about infinity distance performance, though the specs themselves seem to discourage that.

I no longer have any of the old silver Componons on hand, nor even any Componon-S, to test in that regard. But yeah, if I were in your shoes, I might try an older Componon, shutter equipped. They had a great reputation for tabletop studio work.