240mm, 360mm or 135mm/150mm for 4x5 enlarger

[Patrik Roseen]

I know that the normal enlarger lens for 4x5 is 150mm or 135mm. Most lenses create prints that are sharp in the center but softens further out. Now this is also true for lenses used for 8x10 enlargers when producing prints from 8x10. First question: " Would a 240mm or even 360mm Rodagon produce sharper prints from a 4x5 negative than a 150mm Rodagon?" Second question: Will the print using a 240mm or 360mm produce any strange effects since it is not considered a 'normal' lens for 4x5? Kind regards, Patrik

[Nick_3536]

I'll go out on a limb and state most 4x5 enlargers will have trouble with a 240mm and a lot of trouble with a 360mm. Measure the enlarger bellows.

[Patrik Roseen]

Nick, I certainly have the bellows for 240mm and I could also use my Linhof Technika using my Linhof Kondenser attached to the back and probably get away with the 360mm also. /Patrik

[paulr]

the only strange effect you'll see from a longer lens is less sharpness. all else being equal, it will be more even from center to corner than the lens that's designed for the format, but it will give a lower quality image overall.

many moons ago when lenses weren't as good, it was a common trick to use a lens for the next biggest format (80mm lens for 35mm film, etc.). but this doesn't make any sense anymore. check out mtf charts on the schneider site for evidence of this.

[Patrik Roseen]

Thanks Paulr, now that's interesting...so if we turn it around, say that we were to crop an image while doing the enlargement, say choosing a 4x5" area of an 8x10" negative , we would benefit from changing to a 150mm lens instead of the 240mm and the same for cropping a 4x5" neg into a 6x9 we should use something like 105mm instead of the 150mm. Back to my original question -Anyone having hands on experience??

[Oren Grad]

say that we were to crop an image while doing the enlargement, say choosing a 4x5" area of an 8x10" negative , we would benefit from changing to a 150mm lens instead of the 240mm and the same for cropping a 4x5" neg into a 6x9 we should use something like 105mm instead of the 150mm

This assumes that you have an enlarger head and negative carrier that allow you to move the negative relative to the lens (or vice versa) so that the desired crop is centered in the optical path.

[Ken Lee]

Would a 240mm or even 360mm Rodagon produce sharper prints from a 4x5 negative than a 150mm Rodagon ?



If longer lenses for enlarging perform as well as the shorter ones, that would be an exception to the trend we observe with taking lenses. In general, "normal" length taking lenses outperform their longer relatives. Even the center-most resolution of a longer lens, may not match the overall performance of a shorter lens.



That aside, the longer the enlarger lens, the higher up you have to raise the lens above the paper - and unless your enlarger is very well anchored, this introduce the potential for vibration.

[Roger Scott]

My 4x5 enlarger won't handle anything larger than a 150mm lens due to the 72mm or larger lens thread size.

[resummerfield]

A 180 lens for 4x5 may give slightly more resolution in the corners, and probably slightly less light falloff. These improvements would probably be noticeable only in higher magnification enlargements, in which case the longer lenses would probably run out of bellows or column height. Adding bellows or extending the column would probably result in some additional vibration.

[Kevin Crisp]

Patrik: I question your assumption that "most" enlarging lenses are soft at the corners. I had a vivitar lens like that once, but once I got the Nikkor it was never a problem. An enlarger that is properly aligned at all stages makes all the difference in the world.