Bob raises a good point; in my experience process lenses were usually used in th e range of f22-f45. When using high-contrast materials and/or halftone screens, there's very little concern about the effects of diffraction. Otoh, we sure don't want to print at f22 and smaller apertures.
I should have put in the details of the tests... The enlarger was perfectly aligned using mirror tools, negative sandwiched between two glass plates, same negative, developer, paper, and print session. The negative was a 5x7 Trix negative developed in Rodinol, masked down to 4x5 size. The scene was of a wet rock on Pebble Beach in late evening light, with lots of fine detail of textured wet rock, tiny water puddles, wet pebbles in the shade of the rock, and fine specular highlights. I thought this would be a good test of an enlarging lens due to the sharp grain of the negative, the micro details, the extreme contrast, and highlight seperation.
I tested a 135mm componon s, 180mm Fuji AS, 210 Gclaron, a 180mm Rodagon (with slight coating damage) and an old 190mm enlarging Raptar. Print size was 16x20 on Agfa Multicontrast RC paper (did not want to baby sit Fiber for this test). The negative was carefully focused using a Peak grain focuser, and grain was sharp corner to corner. Each lens was focused on the center of the negative.
All lenses were set at f11, thinking this would be closer to the optimum aperature for the 135 reference. The prints were examined at about 1 foot viewing distance in bright light. Except for the 190, which was noticably soft in the corners, all the others were equal in sharpness. Only the Fuji was noticably better in "snap", and had a bit better highlight seperation. The 135 and 210 looked almost the same, except the 210 was slightly sharper in the extreme corners. The 180 rodagon, in this and some other tests, was very slightly less sharp, but it was not a perfect specimen anyway.
These results were not what I expected or wanted to see, since I'm trying to convince myself to buy a new 210mm enlarging lens. More testing may reveal different results. But I think a greater improvement to print quality will come from more printing practice than the differences in these lenses. None of these lenses would reduce the enjoyment of a well conceived image and well executed print. I'm sure that an enlarging lens, optmized for the task, is better than the process lens. But for moderate size prints from large negatives, it was not apparent.
I live in the SF bay area, and anyone is welcome to see these prints. Maybe you will see something I did not.
>> I tested a 135mm componon s, 180mm Fuji AS, 210 Gclaron, a 180mm Rodagon (with slight coating damage) and an old 190mm enlarging Raptar. Print size was 16x20 on Agfa Multicontrast RC paper (did not want to baby sit Fiber for this test). The negative was carefully focused using a Peak grain focuser, and grain was sharp corner to corner. Each lens was focused on the center of the negative.
Why would you test a lens with visible damage? If the lens was mis-treated enough to have visible damage then it could also easily have internal problems that are not visible.
I guess you mean the 180mm Rodagon with coating damage, it also has a dent -- it's seen better days. Amazingly, without comparison to the 180 Fuji or 135 Componon-s, the prints look great. I tested it and the 190 Raptar just out of curiosity to see how bad a lens could be and still deliver decent results. The glass on the others is visibly perfect.
Thank you to all who have respond to my original question; using an enlarging lens for Marco work. The tread has now changed to testing enlarging lenses. That's ok- the learning curve never ends. I did not know that Fuji made enlarging lenses. The idea with the enlarging lens is just to try it out and see If I even like this type of images. If so then I will buy a proper macro lens. I have heard that G Claron, Rodenstock 150mm f9 and red dot artars are good for macro work. Any thoughts on a macro lens ???
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