2x 610mm f/6 Aero-Ektar Lenses. What would YOU do with 'em?

<p>Hope this is the right least-of-several-evils forum choice to ask about these beasties (alternative cameras? classics?). I figured the LF guys would be the most likely to have some comments, as my Google Fu seems to associate various Aero-Ektar lenses with adaptation to LF use. <br /><br />Trying to decide what to do with two of these. For decades-old dust collectors, they're in remarkably good shape. A fleck or three of internal dust, but the irises still work smoothly and glass isn't beat up. I have no idea if the rear elements are as radioactive as some people report. I'm not glowing yet, but nor do I hold them up to my eyes for long periods, just in case!<br /><br />So: any guidance as to the right disposition for a pair of these hefty, large assemblies? I don't (and am unlikely to any time soon) practice any sort of photography that might put these to use, and I don't have a vintage WWII aircraft from which to perform airborne photography across enemy lines.<br /><br />Thanks in advance for any insight!</p><div></div>

<p>Some imprint detail.</p><div></div>

<p>Rear, with flexible iris control device. Which, amazingly, works like a charm.</p><div></div>

<p>Someone was able to get $750 for one of these on ebay in the past couple months... so perhaps you could sell them there?</p>

<p>Hi, Sheldon. Thanks.<br /><br />I've considered going that route, but find myself wondering if there's something more interesting or exotic to do with them. At least the eBay route would likely put them in the hands of someone who'd put them to good use.</p>

<p>11x14 Collodion stereo camera!!!</p>

I had one of these without the

diaphram assembly and was

intending to build a wide field

telescope. The biggest problem

I had was tube baffling to

increase contrast and ultimately

acquired a telescope objective

that performed much better. The

weight of this lens was too much

for my view camera. I still

have a red and yellow filter

that came with my lens ... if

your buyer needs filters,

contact me.

<p>Thanks, John(s)!</p>

<p>Matt, you can always go to Hernandez and try to catch that moon :>) like AA did. Though he used 26", I believe.</p>

<p>Les</p>

<p>The glass yellowing does indicate radioactivity. It can be reduced with exposure to sunlight or UV light. The EE in the serial number indicates a 1944 year of manufacture. I had a 7 inch Aero Ektar that sold quickly, if that is any encouragement. </p>

<h1>Go for being a super photographer! If you build a simple box camera using 11" X 14" photo paper as the negative, then I calculate that you could get a <em>one thousand, five hundred and seventy-five</em> megapixel image. See my 6X18 (cm) camera at <a href="http://www.xtremedigitalphotography.com">www.xtremedigitalphotography.com</a> to get ideas how you could do this. Really, it would not be very difficult.</h1>

<p>Leszek: I'd have to spend more time in Hernandez than I have right now. Man, it's never about the gear, it's about the time, isn't it?<br /><br />David: Yeah, the more I read about these lenses, the more clear it is (pardon the pun!) that I probably don't want to try taking them in carry-on baggage!<br /><br />John G: Fun! It's been some years, now, since I spent time in a darkroom. These crazy lenses do kind of call out, don't they.</p>

<p>They are the two lenses off an Eastman Kodak 24" focal length, stereoscopic, aerial reconnaissance camera which was about 30" long. These used a ten inch B&W roll film cartridge which was synchronised to the over-land speed of the plane. These particular lenses were probably used for 3D side scan applications to gauge shape and height of the target etc . They were also used in combination with a longer vertical camera that used lenses that were 5" in diameter. The resolution of these bigger cameras was 1 yard at 30,000 ft. They are pretty useless without the rest of the camera. The glass elements are very soft and hand ground. In the 30's and 40's Kodak was right up there along with Zeiss and Nikon (which the bad guys used) in photographic development. The roll cartridge of exposed film was hooked up to, and the film fed into a mechanical developing machine which then contact-processed the negative into a long 40' strip of print, then cut into 10x8 contact sheets The whole process of development to print took less than 30 minutes. A plane such as a Moscuito could photograph a ten mile long by 5 mile wide piece of the ground in 4-5 passes. The National Geographic Society has the prints taken along the Normandy coast prior to D-Day. The US air force was still using these cameras in the cold war. As shutter and film ISO speeds increased they were able to freeze motion in a plane traveling at 500kts such as the RB47. At one stage the British installed them in high altitude bombers at up to 45,000'. These had massive objective lenses the size of dinner plates and the focal length was about 10'. These were still being used until satellite photography made the collection of imagery much safer.</p>

<p>The whole story of spies in the skies is a fascinating one, and for me a family affair. My father flew RAAF recon flights in WW2 to the Solomons, New Britain and New Guinea. They used Catalina's and in many they actually developed the film on board and radio'd the info to ground or naval forces once reliable and compact radios were in use. These flights sometimes took over 14 hours. and flew out of Townsville, Queensland in Australia. They were painted matt black and their other role was in air sea rescue of downed US flyers, or inserting or picking up coast watchers in the Solomons and Bougainville.</p>

<p>It was this cooperative effort in the battle of the Coral Sea, Battle of the Solomons and campaigns in New Britain and New Guinea that was the birth of the alliance of the USA, Australia and New Zealand which was formalised into the ANZUS treaty in 1951, where each country would assist any or all of the others in times of conflict in the Pacific area and is the foundation of our defence alliance with the USA.</p>

<p>Fascinating, Francisco - thanks!</p>

<p>Francisco Salaquanda wrote:</p>

 

<blockquote>

<p>They are the two lenses off an Eastman Kodak 24" focal length, stereoscopic, aerial reconnaissance camera which was about 30" long. These used a ten inch B&W roll film cartridge which was synchronised to the over-land speed of the plane.</p>

 

</blockquote>

<p>Interesting, if true. </p>

<p>Why do you believe that they were used on a stereo camera? I ask because the inter-lens distance has to be quite short and because the standard way of getting stereo pairs in aerial photography is to take two shots in sequence; the aircraft's movement provides the separation.</p>

<p>And why do you believe that WW-II vintage aerial cameras had forward motion compensation? Do you have a reference for its implementation that early?</p>

<p>You mentioned the de Havilland Mosquito, which the RAF adapted for high altitude photo reconnaissance as the Mosquito PR, in a variety of Marks. If you'll look in R C Conyers Nesbit's book Eyes of the RAF, you'll find that the RAF didn't use US-made aerial cameras or lenses during WW-II. The UK had a robust and very capable optical goods industry.</p>

<p>I am happy to be proved wrong but I tend to agree with Dan that these (magnificent!) lenses are unlikely to have been used by the RAF during WWII or after. It seems to me they are more likely to have been used by US forces. Here is a shot of a wartime 30 inch f6.3 RAF photo-reconnaissance lens made by the National Optical Company of Leicester, a factory with a core staff from TTH designed to increase wartime capacity. It is based on a Dallmeyer design and was typical of wartime production. It has the UK armed forces broad arrow stamped on it and an Air Ministry specification code. <br /> As far as I am aware any normal equipment used by the British armed forces had (and still has) these marks.<br /> As well as Nesbitt's book mentioned by Dan there is also the less detailed but more contemporary book based on her wartime exploits called 'Evidence in Camera' by Constance Babbington-Smith.<br /> Matt, I think the yellow tint is down to the Thorium doping of the glass to get the right refractive index. It is radioactive but I believe that tint can be reduced by exposure to strong UV.<br /> I found with the lens shown that the sheer weight was enough to make almost any application a real labour of love. In addition the optical quality didn't really justify an astronomical use. Having played with it and found out as much as I could about it....I sold it.</p><div></div>

<p>Hi Matt. I can confirm that the Aero Ektars are <em>very</em> radioactive. The inner rear element contains Thallium oxide. When first manufactured the Thallium component was an alpha emitter. Now, alpha particles aren't very energetic and are easily stopped, so just putting metal lens caps on the lens would have rendered it fairly safe. Besides, those lenses were developed for war work back when nobody cared too much about a small dose of radiation. <strong>But</strong> (big but) that was over 60 years ago, and in the meantime the Thallium with it's short half-life, has progressively decayed into a Gamma emitting isotope.</p>

<p>A few years back I ran a dose ratemeter over the 7" f/2.5 version of an Aero Ektar and the thing positively sang! I interposed a 2mm aluminium plate with almost zero affect on the particle count. Next came a steel plate - and still the meter buzzed away merrily. After I'd put two 4" lead bricks between the meter and the lens with negligible attenuation I concluded I wasn't dealing with an alpha emitter any more. At over 200 counts per second of gamma particles, that 7"Ektar would easily be deemed hazardous radioactive waste. I'm pretty sure it isn't strictly legal to be sold or disposed of in any simple way.</p>

<p>I imagine that its bigger 24"cousins are even more radioactive, but it depends on the mass of the Thallium glass used. YMMV.</p>

<p>As I see it, you can do the right thing and investigate how to legally dispose of those radioactive lumps - which might be quite costly. Or you can play ignorant and try to sell them to anyone naïve enough to want to buy them. Or you can dig a hole about 30ft deep and bury them in it.</p>

<p>Rodeo conflates thallium with thorium, but no big deal. It seems the original element used in manufacturing these lenses was thorium, and one of its radioactive decay products is thallium-208. The Tl-208 is the source of the high-energy gamma photons. At least so says Dr Michael Briggs on his <a href="http://home.earthlink.net/~michaelbriggs/aeroektar/aeroektar.html">web page about Aero-Ektars</a>, and he should know.</p>

<p>Where is Michael Briggs, by the way? He has not posted here since April. I hope he's well. </p>

<p>Thanks, everyone, for the ongoing conversation. Dr. Brigg's page was an interesting read.<br /><br />I've noticed that several insects around the house are glowing green tonight, but I think they're probably just July fireflies. <br /><br /><br /></p>

<p>Thanks Dave. I knew that thallium was involved somewhere. Couldn't remember or find a definitive source that the original doping of the glass was thorium or not to be honest, but I remember that our radiation protection officer was most intrigued that something as innocent-looking as that lens was making his ratemeter buzz so insistently. He looked into the likely suspects and concluded that a decay product thallium isotope had turned into a hefty gamma emitter over time.<br>

After that I somehow lost interest in "playing" with that Aero Ektar. I also stopped using it as a decorative paperweight.</p>

<p>Incidentally, Wikipedia (I know!) lists Thallium Oxide as a high refraction glass dopant, but says nothing in its article about Thorium as such. I'll probably stop using Wikipaedia as an aide-memoire.</p>

<p>I would buy or build a ULF camera to hold at least one of them.<br>

what about a Gowland-style <strong><em>TLR</em></strong> in 8x10 or larger?</p>

This video might answer a lot of the questions raised about these lenses and how they were used.