Modelscopes

[Harold Gough]

Does anyone have any experience of these (?) precursors of endoscopes?

Essentially, they are like an inverted periscope to get shots e.g. in amongst vegetation.

(One was used for filming the aerial dogfight between the tall structures in the film Star Wars).

Olympus made one but I have seen only one for sale in many years.

(I have seen a couple of older strings which refer to an endoscope lens.)

Harold

[DaveW]

I found these links Harold. Oxford Scientific Films used something similar to film at virtually ground level with their Cosmoglide, but theirs had a mirror set around 45 degrees at ground level (reverse periscope fashion) that reflected up to a lens system in the tube because they claimed using a lens facing forwards at ground level they could not get the centre of the lens close enough to the ground for their purposes but the mirror could be angled to reflect the image required to the centre of the lens. I presume it would be a surface silvered mirror to prevent double reflections.

http://www.luminous-landscape.com/forum ... 13241.html

http://www.tut.fi/units/arc/amltech/eaea/modelscope.htm

DaveW

[Harold Gough]

Dave,

Thanks very much. Invaluable info.

I have been thinking about prisms, and some old binoculars have been avoiding my gaze.

Actually, as I write this I realise another possibility. I have a microscope drawing tube which has a half-silvered mirror, plus another mirror, in a periscope-like device. I must dig it out and see how far it gets me. (It requires the light from the specimen and the drawing paper to be balanced so that both images are seen). The device is rather bulkier than what is required for any final use.

Harold

[Harold Gough]

A fortuitous mention of relay lenses in another string suggests a possible way forward. These lenses transmit an image over some distance, inside an optical system, without altering its magnification, just what is wanted for the straight section of the image path! .

Harold

[g4lab]

Endoscopes come up on ebay all the time.
They behave like small wide angle lenses with pretty much distortion and require a lot of light. They are usually in "focus" if you can call it that from
front lens (usually plano) to infinity.

The image on many modern units is transmitted by coherent fiber optic bundles which is the resolution limiting factor though there are surprising numbers of very small fibers in some of them. There can also be gangs of relay lenses or rod lenses

Camera adaptation couplers are also available for many common mounts.
In the operating room and industry C mount cameras often 3ccd units are attached to these. It is similar to an eyepiece adaptation on a microscope but the connection needs to be mechanically rugged. The Field Number is typically less than on a microscope.

If you think you need to have one of these you can PM me and I can probably help you find one.

The guy that invented Arthroscopic Knee Surgery was a resident in the department I worked in. I set up the first system used here in St. Louis. (1977)
Also sold that kind of gear.

Gene