enigmatic "lens" or The packaging of the Void

[AgX]

Come home from the fleamarket, puzzled...

Found a box designated as "Elmo Super Zoom Converter FP-C". (Thus some cine stuff.)

Inside the box one of those hard plastic, transparent domes to screw a lens onto ist base.
Base has got a M25x0.5 thread.

Screwd onto the base is a aluminium barrel looking like the front part of a projection lens. Though extremely well finished.

At the front a designation ring: "Elmo Projection Lens F 1:1.3 f=25mm"

Inside it is machined as plain flat cone (25-30mm dia.) with a perfect flat black finish.


For the rest: NOTHING

 

[lxdude]

Lens hood?

 

[AgX]

A projector lens does not need a lens hood.
Well, one could think of stray projection light originating from within the lens and that should not stray into the room, but the stray light from the screen filling the room should be much worse.

(It would be the first lens hood too that I come across bearing the lens designation, but of course one cannot exclude such. And it even would make sense if that would be part of the lens and no accessory.)

But mechanically it would be a sound explanation. A lens hood put into a box designed for a screw-in zoom converter (after mounting that converter).

 

[AgX]

Well, that converter is indeed screwd onto the lens of the Elmo FP-C projector.

However on no manual or photograph of any Elmo projector with that lens I could find that enigmatic barrel...

 

[Alex Muir]

I have the Ilford Elmo FP projector for Standard 8. The lens is the Elmo f1:1.4 18 mm. The lens is mounted in a fixing that screws to the main body. There is a focus knob on the side of this housing that moves the lens in or out to focus. The front is an aluminium barrel like you have with lens details at the front and black inside. This part unscrews, leaving the optical parts in the focus housing. I suspect it comes off to allow cleaning of the front element. You would need to unscrew the focus housing from the body to release the actual lens. It sounds lik you have an accessory zoom lens, but missing the lens itself. I have some old cine literature. I will look for a picture of the FP-C projector. Alex

 

[Alex Muir]

I found some reference to the projector in a 1967 catalogue, and mention of the zoom converter. The piece you have must have been unscrewed from the original lens to allow the converter to be attached. The original front barrel would then be stored in the converter packaging. It is the front part of the lens that is not required when the converter takes its place. Alex

 

[AgX]

Thank you Alex. That empty barrel covering the lens as you describe is interesting. The black inside seems to be due to the front of that barrel most probably protruding a bit over the lens assembly.


I just realized that I overlooked one page on the FP-projector manual. There it is described to take off a barrel covering the lens assembly to attach the zoom converter to the front of the, now naked, lens assembly. That explains my weird "empty barrel in the zoom converter box" find. Nearly...

Nearly, as my barrel has at its back a female thread wider than the inner cone of the barrel. This is screwd to the base of the lens assembly. How can it be pulled over that assembly, with the front of that assembly still bearing a male thread of the same dimension (to accept the zoom converter) ?

That would not be possible.



But I have to admit this all is of pure academic interest (other term for curiosity) but of no practical means to me...

 

[Alex Muir]

Hi. There were three dual gauge projectors called FP-A, FP-B and FP-C made from 1967-1969. Their design was similar to the original FP. The FP-A was most expensive, and came with a fitted zoom of 20-32mm. It was 65 UK pounds compared to 55 for the FP-C. 10 UK pounds would have been a lot of money in the late sixties. The main difference seems to have been the lens. The FP-C had the 20mm with the option of a converter. I don't know about the B model, but all FPs were gone by 1969, and replaced by the Brilliant model. I think the old FP for Standard gauge had the removable barrel also to accommodate a converter, but possibly of different dimensions. I still use my FP to project my sStandard 8 films from a few years ago. It is a great machine, although I am still looking for a Bolex 18-5.... Alex