$20 LASER Enlarger Alignment Tool

[Bob Salomon]

No...

Bob, the Rodagon R excels at 2x, it is in its sweet range, while Rodagon N is optimized for 10x and recommended for 2x to 15x: yes, it also works for 2x, but this is because enlargement is low and we are ok with 10lp/mm on the print.

Then if we inspect with a magnifier a x2 print made by Ansel Adams (the Clearing Storm in the MoMA is 15 1/2 x 19 1/8", https://www.moma.org/collection/works/52135) perhaps we won't see a detail better than 6 lp/mm, the required one to see a perfect print, but this is not because the 810 negative has 12lp/mm enlarged x2 !!!

If a 810 negative has say 30 lp/mm and we enlarged it x2 with a regular enlarging lens we wont obtain 15lp/mm on the print, if we want that we need a reproduction/duplication lens that excels at x2.


Of course if enlarging x8 a MF negative with a Rodagon D it would be pitfall, while a N would be a nice choice, no doubt.


So what I say is that those that juged Ansels' negatives from 2x prints are wrong, because regular enlarging lenses (at 2x) won't show in the print what enlarging potential the negative has.

Unlike you, I have received calls from people that thought like you about these lenses. The duplicating lenses are lousy enlarging lenses.

[Pere Casals]

Unlike you, I have received calls from people that thought like you about these lenses. The duplicating lenses are lousy enlarging lenses.

Bob, I agree with you that if we are going to enlarge (say) 5x then a Rodagon-D cannot compete with a Rodagon N, at all. True...

But this Apo-Rodagon-D has the Highest quality at 2x, Rodenstock said: https://onedrive.live.com/?cid=8D71B...%21324&o=OneUp

Of course you gave good advice to customers if recommended recommended a N instead a R for darkroom printing, this is because even at 2x the N will make a sound print, because the enlargement factor is low and the better R performance (at 2x) is not perceived by a human eye. So the N will work ok from 2x to 15x, and beyond x15 a G is a great deal... OK, I agree.

But I was not speaking about that...

What I was saying is that we cannot judge the enlargement potential of AA's negatives by inspecting his 2x prints with a magnifier, because while regular enlarging lenses may deliver a good enough 2x prints... only a fraction of the detail in the negative ends in the print, and this is because regular enlarger lenses are optimized for higher enlargements. Isn't it?

If the 2x enlargement of the Clearing Storm in the MoMA was made with a R then an inspection of the print with a magnifier would say how a 4x enlargement would be, this is because the enlargement factor is good for a R.

[Drew Wiley]

Gosh Pere, you should spend less time crunching numbers and more looking at actual prints. AA's enlarging lenses probably weren't all that good either by today's standards. He was primarily a commercial photographer most of his life, a moderately successful one, but hardly equipped like a serious photo lab even back then. He certainly couldn't afford the best gear, though his cameras improved.

[Bob Salomon]

Bob, I agree with you that if we are going to enlarge (say) 5x then a Rodagon-D cannot compete with a Rodagon N, at all. True...

But this Apo-Rodagon-D has the Highest quality at 2x, Rodenstock said: https://onedrive.live.com/?cid=8D71B...%21324&o=OneUp

Of course you gave good advice to customers if recommended recommended a N instead a R for darkroom printing, this is because even at 2x the N will make a sound print, because the enlargement factor is low and the better R performance (at 2x) is not perceived by a human eye. So the N will work ok from 2x to 15x, and beyond x15 a G is a great deal... OK, I agree.

But I was not speaking about that...

What I was saying is that we cannot judge the enlargement potential of AA's negatives by inspecting his 2x prints with a magnifier, because while regular enlarging lenses may deliver a good enough 2x prints... only a fraction of the detail in the negative ends in the print, and this is because regular enlarger lenses are optimized for higher enlargements. Isn't it?

If the 2x enlargement of the Clearing Storm in the MoMA was made with a R then an inspection of the print with a magnifier would say how a 4x enlargement would be, this is because the enlargement factor is good for a R.

Pere, unlike you I have had to talk to extremely disappointed users who made the same assumption you are making and actually bought the D to make enlargements.

It simply isn’t an enlarging lens. It is strictly a duplicating lens.

[Pere Casals]

Pere, unlike you I have had to talk to extremely disappointed users who made the same assumption you are making and actually bought the D to make enlargements.

It simply isn’t an enlarging lens. It is strictly a duplicating lens.

Of course, if somebody bought a D for 5x... he would be have been well disapointed.

But tell me a lens that would make a better 20x16" print (from a 8x10" negative) than a R or a D... where is such a lens ?

We have a lot of Rodagons: HR, R/D, the plain, the N and the G. Each version is desingned to excel in a x range.

[Bob Salomon]

Of course, if somebody bought a D for 5x... he would be have been well disapointed.

But tell me a lens that would make a better 20x16" print (from a 8x10" negative) than a R or a D... where is such a lens ?

We have a lot of Rodagons: HR, R/D, the plain, the N and the G. Each version is desingned to excel in a x range.

The Apo Rodagon D is made in 3 different lenses, 2 are 75mm and 1 is a 120. None would cover an 810. The best lens for your example would be a Rodagon.

[Pere Casals]

Gosh Pere, you should spend less time crunching numbers and more looking at actual prints. AA's enlarging lenses probably weren't all that good either by today's standards. He was primarily a commercial photographer most of his life, a moderately successful one, but hardly equipped like a serious photo lab even back then. He certainly couldn't afford the best gear, though his cameras improved.

Drew our off topic was about if AA's negatives are blurred or not. What I say ¡s that we cannot judge that from his 2x prints because even today regular enlarging glass is not good at 2x.

IMHO he was using a Cooke Triple with wisdom. The Moonrise was taken at f/32, an aperture that was not to limit the performance of his lens while ensuring focus depth in the negative plane, and then he nailed the exposure having lost the photometer, so a perfect job.

[Pere Casals]

The Apo Rodagon D is made in 3 different lenses, 2 are 75mm and 1 is a 120. None would cover an 810. The best lens for your example would be a Rodagon.

This is in the new market, but in the "not new" market we have the R 210 that covers well 810 at 2x, or the R 240, that would not be beaten by regular enlarging lenses at 2x. Another thing is that probably we would need a magnifier to see the difference.

Sure a R is a pitfall for 35mm, for MF and even for 4x5, if not for duplicating slides, because greater than 2x is common. But IMHO for 8x10 an R can make sense for extraordinary 20x16 prints (2x) that would show a surprising amount of detail when inspected with a magnifier, with quality closer to contact print quality.