how to get a 4x to 5x from my 4x5?

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Sam Carleton - 22 Jan 2005 04:15 GMT

I am trying to get something that is around 1 inch to 1 1/4 inches
wide onto a 5 inch peice of film with the equipment that I
currently own.

First the subject: a medium sized animal. Point being is that I
figure that I will place something stationary at the focus point,
and then move the animal into place, and use my strobe to capture
the image.

LF Equipment:
* Linhof Technica III (Max bellow length is around 16 inches)
* Rodenstock 135mm Apo-Sironar-N

Enlarger lens:
* Schneider APO-Componon HM 4/150
* Rodenstock Rodagon 80mm f/4
* Rodenstock Rodagon 50mm f/2.8

Lighting:
* 3 - White Lightning 1200 Ultra's

Now, it looks like with the bellow length that can be achieved
from the camera, the LF lens can only give me about a 2x, not the
4x to 5x that I am after. It is my understanding that some folks
will attach enlarger lens to LF cameras to get to the
magnification I need. But I don't understand how to do it
considering my shooting situation. Here are the Q:

1: I have to reverse the lens, does that mean it sticks into the
camera? If that is the case, do I have to stop it down first?
2: What do I do about a shutter?
3: If I am to go without a shutter, how do I trip the strobes?

Any and all other does and don't would be wonderful!!!!

Sam

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Wilt W - 22 Jan 2005 06:16 GMT

<<Now, it looks like with the bellow length that can be achieved
from the camera, the LF lens can only give me about a 2x, not the
4x to 5x that I am after. It is my understanding that some folks
will attach enlarger lens to LF cameras to get to the magnification I need. >>

Have you merely considered getting another focal length view camera lens?

If you try to use enlarger lens, the lack of any shutter will mean that you
have to rely upon the lighting to provide ALL of the exposure, but you have to
work in total darkness until the subject is in place and you fire your White
Lightnings!!!

According to my calculations, to fill 5" film with 1.25" subject, that
translates to 4x magnification. To get 4x using 135mm lens requires 540mm of
bellows extension. If you use 100m lens, that takes 400mm of extension. So I
would look for 75-90mm lens to shoot at the magnification you want, as that
uses 300-360mm of bellows extension.

--Wilton

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Bob Salomon - 22 Jan 2005 10:33 GMT

> I am trying to get something that is around 1 inch to 1 1/4 inches
> wide onto a 5 inch peice of film with the equipment that I
[quoted text clipped - 32 lines]
>
> Sam

You need a Reverse Mount Adapter to mount the lens and a #1 shutter to
screw the reversed mount in to. Rodenstock does make a Revers mount Ring
for any enlarger lens with a 40.5mm front filter thread. You also have
to block the illuminated aperature port on the rear of the lens.

Signature

To reply no_ HPMarketing Corp.

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f/256 - 22 Jan 2005 13:33 GMT

> I am trying to get something that is around 1 inch to 1 1/4 inches
> wide onto a 5 inch peice of film with the equipment that I
[quoted text clipped - 6 lines]
> magnification I need. But I don't understand how to do it
> considering my shooting situation. Here are the Q:

For 4X magnification, the bellows extension you need would be 5 times the
focal length, if you have a 75mm lens, the bellows extension needed would be
75 x 5 = 375mm. and your subject has to be placed at a distance equal to
1/4 the bellows extension from the front nodal point of the lens, in the
case above, using a 75mm lens the bellows extension is 375mm and the
"working distance" in front of the lens is 375 / 4 = 93.75mm. Your DoF
will be very shallow, of course.

Enlarger lenses, I understand, are symmetrical or close to that, I'd just
take my 75mm enlarger lens and mount it unreversed instead of a lens of your
camera. If you wanted it reversed, then mount it from the rear of the lens
plate, if you do this, you may have to use a smaller focal length lens as
mounting it at the rear put the lens inside the bellows and closer to the
film plane. Exposure time would have to be controlled by the light
illuminating your subject.

Guillermo

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Dan Fromm - 22 Jan 2005 13:57 GMT

> > I am trying to get something that is around 1 inch to 1 1/4 inches
> > wide onto a 5 inch peice of film with the equipment that I
[quoted text clipped - 24 lines]
>
> Guillermo

Guillermo, although some enlarging lenses perform well above 1:1 whem
mounted normally, they really are optimised for "large behind, small in
front." Most of the ones I've used above 1:1 have done much better
when reversed.

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gdstewart@worldnet.att.net - 22 Jan 2005 20:10 GMT

Be carefull of blinding what you might be photographing. I've read that
in certain case, especially with sea-life, permantent blinding may
result when the organism is exposed to intense strobe light. This is an
especially important issue at your reproduction ratio.

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Sam Carleton - 22 Jan 2005 22:16 GMT

> Be carefull of blinding what you might be photographing. I've
> read that in certain case, especially with sea-life, permantent
> blinding may result when the organism is exposed to intense
> strobe light. This is an especially important issue at your
> reproduction ratio.

Thank you for the warning. The subject has already been under the
full strobe before, so I believe she will be fine. Worse case,
she can close her eyes;)

Sam

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jjs - 22 Jan 2005 22:42 GMT

> Thank you for the warning. The subject has already been under the
> full strobe before, so I believe she will be fine. Worse case,
> she can close her eyes;)

It's a dog, and all he wants is shot of her black nose.

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Chris Ellinger - 24 Jan 2005 15:29 GMT

>I am trying to get something that is around 1 inch to 1 1/4 inches
>wide onto a 5 inch peice of film with the equipment that I
>currently own.

>* Rodenstock Rodagon 80mm f/4

This is probably the best compromise of bellows extension and working
distance.

>1: I have to reverse the lens, does that mean it sticks into the
>camera? If that is the case, do I have to stop it down first?

Find an adapter ring that fits the front thread of the lens, and glue
it to a lensboard. The lens will be outside the bellows, with the
rear element facing the subject.

>2: What do I do about a shutter?

If you can darken the room, you won't need a shutter. Focus, turn the
modeling lights off, remove the darkslide, pop the strobes.

>3: If I am to go without a shutter, how do I trip the strobes?

Trip one strobe with the test button and the others' slaves with fire
them.

Chris Ellinger
Ann Arbor, MI

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