Fujinon C or T?

[paul r w freeman]

I want to get a 240-300mm lens and was wondering if anyone has compared the normal and telephoto offerings from Fujinon.

I need this for a specific project where I need the maximum resolution at infinity, hence I think that Fujinon A series and the G-Clarons might not be the best choice.

For my application I don't need to largest image circle as I only expect to use small movements, however resolution is the most critical thing. (Weight isn't a concern either).

I have adapted an Ebony 45S to take a sliding back and an Aptus 75 and I intend to use the lens with this combo. So good optical performance at f11-16 is the most important thing in order to avoid diffraction softening.

The normal C lens is a bit cheaper than the telephoto T offering, but I'll pay the extra if the resolution is better.

If anyone knows of another 240-300 that is better and in the same rough price bracket I'd be interested in knowing.

Best

[Ed Richards]

> Aptus 75?

Given how small this back is, using regular LF lenses will not be as sharp as sticking it on a MF camera with a 300. What about an RB 67 lens on an adapter?

[Eric Leppanen]

My Fuji 240A at f/16 or smaller aperture is the sharpest LF lens I own, either close-up or at infinity. I don't think you'll find a sharper LF film lens than this, although something like a 240mm APO Sironar-S might work better at wider apertures.

However, my understanding is that your Aptus will start showing diffraction effects at apertures around f/11 or so. Wouldn't you be better off using a digital lens such as the Schneider Digitar or Rodenstock APO Sironar digital, which will perform much better than LF film lenses at such open apertures? Are you looking for a lens for use with both your Aptus and 4x5 film?

[paul r w freeman]

The digital lenses only go up to 210mm, though the image circles are adequate. However these come at a price of more than double that of a Fujinon A 240.

I've found that diffraction effects don't really kick in that badly until over f16. I generally shoot between f11/16. However for the subject matter involved in this project the area of focus is generally over 1/4 mile away to infinity so shooting at f8 or f11 is no problem. The film lenses tend to be f8 or f9 wide open so I guess that they are a little under their optimum at f11. Hence actually f16 might be a better compromise.

I shot some nice tests last weekend with a plain old Schneider 150 Symmar at around f16 and they were nice and sharp. Yes, its possible that a digital lens might be a bit sharper... but I am finding that good film lenses are usable. What I am also finding is that poor samples of lenses are shown up very quickly.

So I have one vote for the Fuji-A 240, with the benefit that I could also shoot on film if I wanted.

[Hany Aziz]

I want to get a 240-300mm lens and was wondering if anyone has compared the normal and telephoto offerings from Fujinon.

I have adapted an Ebony 45S to take a sliding back and an Aptus 75 and I intend to use the lens with this combo. So good optical performance at f11-16 is the most important thing in order to avoid diffraction softening.

Best

I am not sure if your "sliding back" will give you enough bellows extension (max on the 45S is normally 270mm) so you may be stuck with the Tele lens. On the other hand the Fujinon 240 A has an excellent reputation. I have not shot with either but have recently acquired the Fujinon 180 A which I have yet to use much. I do have and love the Nikkor 300 M. Would recommend it if you have the bellows and can find a nice new or used one.

Sincerely,

Hany.

[paul r w freeman]

Hany,

Good point, I still had my 240 hat on, I'd forgotten that the Ebony has that limit. The sliding back adds about 20mm in depth so that only makes 290mm. Looks like I should stick with a better 240mm lens rather than get a 300. Maybe the 240-A which everyone seems to love. I'm assuming that the tele lens might be optically compromised.


I am not sure if your "sliding back" will give you enough bellows extension (max on the 45S is normally 270mm) so you may be stuck with the Tele lens.
Hany.

[Eric Leppanen]

Chris Perez' lens test results can give you a rough idea of what to expect resolution-wise from your various lens options:

http://www.hevanet.com/cperez/testing.html

These tests were performed at 1:20 magnification and not infinity, but in the majority of cases that shouldn't cause much of a difference. The Nikon 360T is probably the best telephoto option available in the 300-400mm focal length (it requires 261mm of extension at infinity focus, within range of your 45S), and you can see that the sample tested fared fairly well in these tests. If you were happy with a Symmar, then a variety of lenses should be good enough for your needs, and it is just a matter of picking the best focal length that fits your camera.

Since you are shooting at a subject over 1/4 of a mile away, smog or haze in the air will tend to limit resolution anyway.

[paul r w freeman]

Thanks Eric, good tip about the Nikon tele. Maybe I could eventually get that as well as a 240.

Dead right about the atmospheric factors, they have a big bearing. In some of the images this is part of the charm, but I want to clear ones to be really clear.