Advice On Purchased Pezval Lens

[Shangheye]

Finally! I managed to win on a certain auction site a 180mm f3.6 Pezval lens. The lens is unmarked, but it was also a bargain.

I have a few questions:

- The lens comes with no Waterhouse stop slot in between the lenses, but does come with a slot at the front. I assume this means I can use this slot for stops?

- How can I date this lens based on the location of this slot..or maybe understand what it was used for...I assume it is a Magic Lantern lens, rather than a Pezval Portrait (I am a virgin here so please educate me!)

- Does the fact that the slot is in front of the lens make a difference to how I would make stops for it (I mean by that the calculation for size etc)


I am looking to use this lens on my Graflex RB Series D (I know focusing to infinity will not be possible, but there is a spare 7mm before my 190mm focuses to infinity, so I think there is some room for getting some distance). Am I correct in thinking

a) the minimum image distance (front standard) to the film will be @ 180mm or are some of these lenses telephoto type designs (I hope not...)

b) Do I set the lens to infinity and then use the bellows to focus?...I assume that is the way I should use it on a bellows camera?


It won't be a disaster if I can't use the Graflex, since I have a Toyo Field Camera...but I liked the option to take Petzval portraits with an SLR...we shall see!

Appreciate all your help....I am VERY excited

Rgds, Kal

 

[John Kasaian]

I've got two old magic lantern lens, a Darlot and a MacIntosh, and IIRC nieither of them have slots for waterhouse stops, so going by that I'd guess that your new lens isn't off a magic lantern (but I could be wrong----it is a sample of only two lens after all!) Why yours has two slots is a mystery to me, but why bother with waterhouse stops on a pretzval anyway? Wide open is generally what it takes to get the swirlies to show up. If I were going to use stops, I'd experiment with using the center slot for stops and maybe make a solid "stop" for the front slot to use as a shutter. Have fun!

 

[Shangheye]

John, I wasn't clear enough...there is no middle slot..the only slot is in the front, in front of the front element in fact. No other slot. I agree the intention is to use it wide open, but I just wanted to make sure I understood the purpose of the slot and date the lens approximately if possible....

Got to wait till it arrives, but I already have omeone lined up to make me a lens board for it..;-)K

Thanks for the input.

Rgds, Kal

 

[Shangheye]

bump

 

[phfitz]

Kal,

on the petzval lenses I have the apertures are at the midpoint of the barrel, which also coincides with the focal length at inf. You would need to mount the board to the middle of the barrel to get inf. focus. Have fun with it wide open and see if you like the look. You could always install a waterhouse disc internally if you need more depth.

The forward slot would be for a vignetter, I doubt that it would work well to stop down the lens.

 

[Shangheye]

Thanks. I guess that means that with a minimum focus distance of 180mm on my Series D Grafelx (because of the mirror), I won't be anywhere near infinity...in fact more like just over a meter away (the lens is 100mm long so if I take distance to the aperture as around 40mm, I assume the aperture is at 220mm away at the closest focus point)...Sounds like I will only be using it on my Toyo!

Rgds, Kal