New to LF, Lens Question

[catmando]

Hi all,

I'm new to LF, having shot 35mm and MF for about 5 years. I bought an Intrepid 4x5 as it seemed nice, new and light. I also found a Pullin Pulnar 100mm f2.8 mounted on a Copal Press 1 shutter. The price was too good to pass up.

Here are my questions:

- The lens is currently mounted on a board I do not recognize (image attached), which has a slight extension and an offset hole. It seems to be Technika compatible and fits the front of my Intrepid. Taking this into account:

• The lens does not seem to cover the full 4x5 ground glass. It seems to suffer from mechanical vignetting no matter how I move the front element (and 100mm is very close to the minimum for this camera, so movements are limited).
  Is this something that has anything to do with the "strange" board?
• I cannot seem to find any information on this lens (although it has been spoken of here). Does this lens simply not cast a large enough image circle at infinity?
• The shutter it's mounted on has an aperture scale that goes to 1.9: any ideas on how I can work out a conversion table for this 2.8 lens?

I appreciate any feedback and hopefully one day I will be in a position to give some help myself.

[Steven Tribe]

deleted!

[catmando]

Um...what? The link mentions the lens but it says nothing about vigentting. I'm a new user and I need some help, so what's the deal?

[Emil Schildt]

too small a lins I think (150 would be normal FL, but it has to be a 150 LF lens... not for MF or 35mm cameras..)

[catmando]

There are 65mm lernses for 4x5 cameras!

[Leigh]

There's a lot more to lens performance than focal length.
For example, a 100mm lens for a 35mm camera will throw an image circle not much larger than 35mm film.
Your lack of 4x5 coverage may be that the Pullin lens is designed for a smaller film format. I've never heard of it.

Your extended lensboard is designed to accommodate lenses of longer focal length than the native bellows will do.
This is less common than recessed boards, but not unheard of. Recessed boards accommodate short FL lenses.

Obviously you could simply shift the front standard forward to support a longer FL, but doing so loses focus range.

- Leigh

[Leigh]

There are 65mm lernses for 4x5 cameras!

That comment is apropos of what?

A 65mm lens on a Minox would be a telephoto.

- Leigh

[Luis-F-S]

You might want to read up a bit more before you buy another lens

[catmando]

Makes sense Leigh, I figured that at least some of the problem might be caused by the board.

[catmando]

Leigh, the 65 mm comment is in reply to "too small a lins I think (150 would be normal FL, but it has to be a 150 LF lens... not for MF or 35mm cameras..)"