Wide Lens - Recessed Lens Board?

[j._scott_schrader]

I just purchased a Rodenstock 75mm f4.5 lens to mount on my

Toyo 4x5 Monorail. The problem I encountered was that the film

plane and the lens are unable to come close enough together to

focus. I am assuming that I will need a recessed lens board to

take care of this problem. Is that assumption correct? Thank

you in advance for your input.

[thomas_diekwisch1]

Yes.

[walt_donovan]

A recessed board for sure. You may also need a bag bellows for this short a lens, especially if you want to use shift.

[leonard_evens]

It does appear that the Toyo monorails can't accomodate a 75 mm lens with a flat lens board. So you will need a recessed lens board. The f/4.5 75 mm Rodenstock Grandagon-N has an image circle of about 190 mm, which allows shifts or rise/fall of only about 20 mm. So you can't make use of exceptionally large movements, and you may not need a bag bellows.

 

I bought such a lens, and I found I had to relearn much of what I thought I knew from using a 90 mm lens. First of all, light fall off is quite obvious in most situations, so a center filter may be necessary. (So far I've been getting by with overexposing and correcting digitally using negative film, but that wouldn't work too well for transparencies.) Secondly, I found I had to be much more careful that my standards were parallel. View cameras may have a small amount of play in the zero or detent positions, and that will produce a slight swing or tilt. For this lens, that can change the subject plane enough to be noticeable under enough enlargement. That can be misinterpreted as a deterioration in lens quality, particularly if you use movements. Since resolution does fall off as you approach the edge of the image circle, it may be hard to separate the two issues. In any case, because of such issues, I found I had to stop down further in some cases than I needed according to depth of field criteria. That surprised me because generally one doesn't need to stop down as much with a wider angle lens because of the greater depth of field.

[joe_photo]

That sounds like a lens made for 3-1/4 x 4-1/4 not 4x5 but I may be wrong.

[j._scott_schrader]

Thank You for your replys...I did purchase the center filter with the

lens in anticipation of the image fall off problem. Thanks to all

for sharing your expertise and experience.

 

Scott