View Full Version : My 178mm Aero Ektar goes to the hospital!

John Kasaian
19-Jun-2007, 17:13
"Is Monica in?" I asked at the window.
"We'll page her. Is she expecting you?"
"Yes. I spoke with her this morning about my radio active lens" I said, resting my well taped up cardboard box on the window ledge.
"Is that radio active?" the receptionist asked.
"I've heard that these are emitters" I replied, "thats why I'm here."
"Where did you get it?" Someone from back in the office asked.
"Why, eBay of course!" I replied.

FWIW The only thing resembling a serial # is hand-etched EE17569 on the barrel of the front element. I took it to the Nuclear Medicine department at the local hospital, seperated the front and rear elements and the techs did the geiger counter thing and then ran it through a camera of some sort that was connected to a computer screen. Here's what they told me: It's giving off one mg of radiation a minute and at a distance of two feet the reading is "background" meaning it is undescernable from background radiation (the everyday stuff) Whatever isotopes it is emitting were not of discernable levels. The cardboard box lined with wonderboard (cement impregnated fiberglass) which I brought the lens in with (I couldn't find any sheet lead) cut the emissions down to .1 mg. The only hazard I was warned of was to avoid using it if I should become pregnant :D , or let children play with it. Either way not a problem and its certainly not a weapon of mass destruction!

This was quite an interesting experience! The nuclear medicine people were very nice and actually took a genuine interest in what I had planned for this grubby old lens. I promised them prints if I get any good ones.

This presents a bit of a hitch in the plans, as I don't want to take my son with me (he's 6) and expose him to the lens for half a day and night, but thats nothing that an overnight visit with his favorite auntie can't fix, is it?


Jim Rice
19-Jun-2007, 17:20
Just watch his distance to it. I had one for years, and just because I'm a drunk in a FEMA trailer shouldn't discourage you. :P

Eric James
19-Jun-2007, 17:29
Increasing his distance from the emitter will certainly help lower his exposure. Do you know what type of particles it's emitting? A Plexiglas shield may do the trick - or a lead-lined film bag. I hope you share with us the image made with your lens and MAD SCIENTIST plan!

Walter Calahan
19-Jun-2007, 17:51
I've got three Aero-Ektars! Never worried about the radiation. We encounter radiation from emitters all the time. Granite buildings probably expose us to more radiation simply by walking through their lobbies.

Posted two images on my home page made with an Aero rigged to my RB Graflex.

Donald Qualls
19-Jun-2007, 18:38
Seems to me the radiation from Aero-Ektars is from thorium doped glass, same as with my Super Takumar 50mm f/1.4 (for M42, on a 35 mm SLR).

Thorium itself is an alpha emitter, and as such as near to harmless as anything radioactive can be providing only you don't ingest or inhale the stuff; a cardboard box will reduce the emissions to background from any reasonable source.

The complication arises as the lens ages, because not all of thorium's decay products are so well behaved; by the time a lens is 50-60 years old, it emits a witch's brew of alpha, beta, and gamma, the latter of which aren't really "stopped" by any easily portable shielding if of high enough energy. The good news is, even with that, the actual emission level is quite low (as you were informed), and the advice I've seen from someone who makes his living dealing with radiation was "don't use it for a loupe, and don't sleep with it under your pillow".

If you don't mind carrying some weight and want the best possible peace of mind, you could make a box for it by casting lead shot in epoxy, a half inch or so thick, with a suitable space inside and a means of latching the lid shut. That's almost certainly overkill for any lens; the box itself (by virtue of its mass, as much as its lead content) is a bigger threat than the lens inside...

Mark Sampson
20-Jun-2007, 04:37
Have you checked Michael Briggs's page about the Aero-Ektars? It should be required reading for anyone who owns one of these lenses.

20-Jun-2007, 05:24
hi john

this reminds me of film "repo man"
... just make sure you don't open the trunk!


Walter Calahan
20-Jun-2007, 06:26
Mr Brigg's page is:


Michael Graves
20-Jun-2007, 07:27
My experience with Aero's was actually quite positive. After years of using them, I can now adjust the tripod with my left hand, hold the shutter release with my right one and wave off mosquitoes with the other two.

Turner Reich
20-Jun-2007, 08:15
Don't hang it around your neck at the thyroid level and don't put it on your lap while driving or sitting for any length of time. Unless you are treating cancer of course.

By the way what kind of radiation is it? That is the most important issue along with the amount.

20-Jun-2007, 10:33
Hmmm I have an ektar too, but as I write this I must admit I slightly more concerned with the hot macbook pro sitting on my lap next to my nether regions.

I think though when I get the ektar mounted into a medallion I should worry :D

Zach In Israel
20-Jun-2007, 22:21
If you just want to see if it is radio active put it in a changing bag on a sheet of b&w film overnight. Thats how radioactivity was discovered in the first place (with a chunk of Radium on some old photographic plates). Of course I have no idea how you calibrate that.

Jiri Vasina
20-Jun-2007, 22:52
Exposing a BW film to radiation is a standard method of dosimetry. As for the calibration, you would have to have a several radioactive sources of known radioactivity in roughly the same volume distribution, place each above a separate sheet of film (exactly same distance). After the development (precisely same), you measure the density of each sheet, create a calibration curve and find out how much radiation was on the sheet below the measured material.

But this is not worth it in this case. You only measure how much radioactive the material is, not what kind of radiation it is and what is the relative distribution of the isotopes. (no spectrometric feature)

The way John did it is very clever indeed. Any gamma camera is capable of spectrometry measurements - identifying the isotopes is rather easy (with the necessary knowledge, which on the hand is not that common among nuclear medicine staff - they don't need to know all the isotopes, only those used in diagnostics and treatment, and those are not part of thorium decay chain).

J Peterson
21-Jun-2007, 05:24
My experience with Aero's was actually quite positive. After years of using them, I can now adjust the tripod with my left hand, hold the shutter release with my right one and wave off mosquitoes with the other two.


Aero Ektars are great! Although people always think I'm being spiritual when I speak of my third eye.

30-Jun-2007, 17:08
I think that the ektar would do more harm to your neck due to its weight if you hung it around your neck. Oh, and don't lick them, they taste bad.