[BigMackCam]

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I'm half way through watching an excellent movie called "The Courier". It's the story of British businessman Greville Wynne's involvement with American and British intelligence services, acting as a go-between with a Russian official during Khrushchev's rule.

There's a scene where a U2 aircraft is about to take reconnaissance photos of Cuba in the lead up to the missile crisis. For a few brief moments, we see the following lens:





It's a Bell & Howell Type 1 36" (913mm) f/8 aerial telephoto lens. Quite the big fella

I wonder how they managed to achieve stability with such a long focal length lens? There must have been a fair bit of vibration from the aircraft...

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Last edited by BigMackCam; 02-20-2022 at 01:20 PM.

[subsea]

I'm half way through watching an excellent movie called "The Courier". It's the story of British businessman Greville Wynne's involvement with American and British intelligence services, acting as a go-between with a Russian official during Khrushchev's rule.


I wonder how they managed to achieve stability with such a long focal length lens? There must have been a fair bit of vibration from the aircraft...

Actually, Mike, at the normal U2 operating altitude of about 60,000 ft, the air density is low enough that there is little to no turbulence, so the vibration felt by the camera would only be that caused by the aircraft systems themselves. It's much easier to create camera mounts to control that than it is to create mounts to control vibration due to turbulence.

[BigMackCam]

Actually, Mike, at the normal U2 operating altitude of about 60,000 ft, the air density is low enough that there is little to no turbulence, so the vibration felt by the camera would only be that caused by the aircraft systems themselves. It's much easier to create camera mounts to control that than it is to create mounts to control vibration due to turbulence.

Interesting... that makes perfect sense. Thank you!

Also interesting - in the very short clip where the lens is seen - is that we see and hear it focusing by motor. I assume this was manually remote-controlled and/or preset based on altitude... or was there some sort of AF capability even back then?

[ofer4]

I've seen one of these in-person. They're every bit as impressive as you might imagine.

[subsea]

Interesting... that makes perfect sense. Thank you!

Also interesting - in the very short clip where the lens is seen - is that we see and hear it focusing by motor. I assume this was manually remote-controlled and/or preset based on altitude... or was there some sort of AF capability even back then?

I could be wrong, but I suspect that what you were hearing wasn't a focusing motor, but rather a steering motor for the lens. The DoF for a lens with those specs is approximately from 2000ft to infinity, so there wouldn't be any need to provide variable focus for the lens on a U2 flying at normal operating altitudes.

[AstroDave]

You can get your own: Bell & Howell 36" in f/8 Type I 922mm Telephoto Vintage Barrel Large Format Lens | eBay

Something sort of doesn't add up here?

A) a 30-inch lens would put this in the top 10 largest lenses in the world! I have looked through 30", 26", and 24" refractors, and seen the 40" at Yerkes - these are GIGANTIC pieces of machinery (although their focal lengths are rather longer)

B) If the f ratio on this is 8, then the focal length is around 8x30" = 20 feet! Unless there were some kind of folded optics in the U2, this wouldn't fit in the plane!

C) The serial number on Big Mack's is weird (look at all those digits - way more than on any camera lens I own) and the serial number on the eBay item is 2276 - I doubt they made thousands of these

If anybody know more about this, I'd love to hear about it.

[marcusBMG]

913mm focal length / 8 = 114.1.. mm, looks about right.

[pschlute]

It is a great film.

[AstroDave]

Well, here's some more info.

This is NOT a 30" diameter lens. This photo (found on the web) shows one of these next to a modest Canon 70-200mm zoom (f/4 I think) which appears to need a 72mm filter. So, the front lens of the Canon is about 70mm across. That would make the diameter of the big lens more like 7-8 inches.

Still, a big lens, but not 30" !! And, I might now believe the 2276 serial number has something to do with how many of these were made, but who used (that many of) them?

Marcus's diameter (114mm) looks a lot more realistic, but still a bit small compared to my estimate (more like 180mm) - but who worries about factors less than 2?

[photoptimist]

The ambiguous meaning of "36 inch" varies because different users of optics care about different parameters.

For photographers, the focal length is the most important number because it sets the angle of view for their chosen format of camera.

For astronomers, the physical aperture is the most important number because it sets both the light gathering power and best-case angular resolution of their instrument.


Designed for photography, this lens has absolutely massive 36" focal length that would impress every member of the photography club. In the astronomy world, it would be called a piddly 4.5" telescope and be table stakes for the astronomy club. ;-)

[pentaxus]

Probably the last few numbers are the quantity made.

[yucatanPentax]

You can get your own: Bell & Howell 36" in f/8 Type I 922mm Telephoto Vintage Barrel Large Format Lens | eBay

Something sort of doesn't add up here?

A) a 30-inch lens would put this in the top 10 largest lenses in the world! I have looked through 30", 26", and 24" refractors, and seen the 40" at Yerkes - these are GIGANTIC pieces of machinery (although their focal lengths are rather longer)

B) If the f ratio on this is 8, then the focal length is around 8x30" = 20 feet! Unless there were some kind of folded optics in the U2, this wouldn't fit in the plane!

C) The serial number on Big Mack's is weird (look at all those digits - way more than on any camera lens I own) and the serial number on the eBay item is 2276 - I doubt they made thousands of these

If anybody know more about this, I'd love to hear about it.

Do you suppose if I were able to mount that ebay lens through the wall of my house, i might be able to project a scene of the outdoors? Hmmmm.... Maybe I'd need a ground glass set up somewhere after the lens? Or somehow adjust so it would project on the opposite wall? It would be like TV, but real life outside seen from a germ-limited living room!

I wonder what size of film was used with that lens?

This item has a 35mm Canon SLR for size comparison in one of the photos
:Giant Fairchild Bell & Howell 36 Inch 924mm f8 Type I Aerial Lens w/ NP Shutter | eBay

[Paul the Sunman]

What's the mount?

[BigMackCam]

What's the mount?

From what I've read, the camera was most likely the large format Fairchild K-38. I assume the lens was mounted directly to a board or front panel...