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Bob Phipps
4-Nov-2005, 09:33
Hi All,

Thanks ahead for info.

I want to buy another lens for my Toyo 45CF. Presently I'm using a 90/f5.6 and a 150/f5.6. I'm looking to go to 250/f6.3 Fujinon-w or a Nikon 210. My thinking is to increase magnification for flowers and forest floor shots, and in camera croping of scenic shots. Being new [1 1/2 years] to LF, help is needed here.

Do you know of any real problems with the Fujinon-w 250/f6.3? This forums discussions have not answered my questions completely.

Books and an Intro to LF class with Danny Burk recently brought me to this point. Danny's info and help was great, but I need just this last bit of fine tuning before buying.

Thanks again.
Bob

Dan Fromm
4-Nov-2005, 10:58
There are many reasons to get a longer lens, but "to increase magnification for flowers and forest floor shots" isn't among them. With the longer lens you'll run out of extension sooner. You'll do better by moving the camera closer to the subject and using one of the lenses you already have, and you'll have a better chance of getting the magnification you want without running out of bellows.

Ed Richards
4-Nov-2005, 11:35
The Fujinon is a terrific lens and a great deal, but as Dan points out, it will only make your problems worse if you want more magnification of close up stuff. It will work very well for cropping your scenics.

robc
4-Nov-2005, 12:43
for 1:1 magnification you need to extend the bellows to twice the focal length and have the subject distance at twice the focal length. Therefore, for a 250mm lens you would need 500mm of bellows extension for 1:1 magnification. For your 150mm lens you would only need 300mm but you need to be that much closer to the subject. All depends on how much magnification you really want. 1:1 is not at all unreasonable for some flower shots.

for 1:2 magnification with a 150mm lens you would need 450mm of bellows extension with the subject at 225mm.

for 1:2 magnification with a 90mm lens you would need 270mm of bellows extension with the subject at 135mm.

so a major limiting factor is bellows extension and for the greatest magnification, a shorter focal length will not hit that limit.

Mark Sampson
4-Nov-2005, 13:30
For "in-camera cropping" the 250 would be a good choice. It's enough difference from the 150 to give some extra reach- I think a 210 would be too similar. My own choice is a 300/9 Nikkor-M- equivalent to a 90mm lens on a 35mm. But the previous posters are correct about long lenses and close-ups.

Bob Phipps
4-Nov-2005, 17:11
Thanks all! It is hard to rethink somethings I've grown so used to doing in 35mm and 645.

Forgot about bellows extension. Yes the 90/f5.6 would be better, dah!

Okay 250 it is.

Thanks again,
Bob