4x5 close-up flower shots - can you suggest a lens?

I am in the process of building a Bender 4x5 kit and am looking for ideas about what kind of lens I should get. I want to do some close-up shots of flowers and such. Would a 210 work, or should I go bigger? I also do a lot of landscape w ork, and have found a 150 or so works fine for me. Right now I am shooting a pre-1950 Speed Graphics 4x5 with a 161mm (I think). I don't have much experience shooting different-sized lenses, so I'm looking fo r some advice before I blow a ton of money on the wrong lens. And, hey, if anybody has a 210 or 250 4x5 in good shape... I'm buying. Thanks a lot.

Well, the longer you go the more bellows extension you will need. A 210 would ne ed 21cm extension to get to 1:1. A 150 would only need 15cm. Macro lenses which a are computed for 1:1 will obviously give you a little bit better performance.

You didn't say what your maximum bellows extension is and I'm not familiar with the specs on the Bender cameras. Assuming that by "close up" you mean something that will give you 1 to 1 magnification, your maximum bellows extension will hav e to be twice the focal length of the lens you are using. For example, with a 15 0mm lens you would need 300mm (12 inches) of bellows extension to get 1 to 1 mag nification. With a 210mm lens you would need 420mm (about 17 inches) of bellows extension to get to 1 to 1. I use a 150mm Schneider G-Claron lens for close ups and it works well with my 13 inches of bellows extension. The G Claron lenses ar e optimized for 1 to 1 magnification but they perform well at any distance and s o are quite versatile. They also are relatively inexpensive - around $450 new. T he Macro-Symmarlenses made by Schneider and the Macro-Sironar lens made by Roden stock are pretty expensive (around $1,300 for the Schneiders and $2,800 for the Rodenstock) and are corrected for magnification ratios between 4/1 and 1/4 for t he Schneider and something similar for the Rodenstock (if my memory is correct). They do not claim to be usable as "normal" lenses. I don't know how much of an improvement they are over a "normal" lens for macro work - I've read that they d on't really provide any significant improvement but I've never personally used t hem.

A follow-up question to this one ; what experience do people have using one of the "close-up" dioptre lenses on something like the Nikkor 300mm f/9 on 4x5?. I have been trying to take some photographs of fungi, and have been using a Nikkor SW120 at 240mm bellows extension in order to approximate 1:1 on film, with pretty good results, but would I get better results by using one of the dioptre lenses? If the dioptre lense simply effectlively reduces the focal length of a lense, will I be better off simply using a shorter focal length lense?

Optimally with 3 dimensional objects the best choice is a macro lens not a process lens.

For close up lenses the single element ones won;t perform well at all, especially on a lens not corrected for the subject matter in the first place.

Multi element close up lenses like the heliopan Achromats will give better performance then straight close up lenses but the result will be less then a true macro.