4x5 or 8x10 not sure wich way to go/can replicate the look of an 8x10 shot wide open

[John NYC]

You might get more than that from flying on airplane , but generally speaking you right - constant exposure is not a good thing.. Can start mutate or worse. And it can be next generation who gets it, unfortunately.

If one has 18 CAT scans in ones life, they have now shown that is a risk. Cancer patients often get a cat scan every couple of months for years. Add to that airplanes, airplane scanners, X-rays, and god knows what else will happen to a person by the time they are 50 or so and well it ain't worth it to me to add to the pile. Besides those lenses are a fad... One hit wonders, to make a pop music analogy.

[Corran]

If you go ahead and search the internet you'll find an article about the AE that pretty much discounts the radiation as trivial. Short of living with it in your pocket it's not going to do anything!

I've got two in my house right now, building a couple cameras. They are unique lenses that are very interesting to me. Still doesn't look like a Schneider 300/5.6 on 8x10.

[Tony Karnezis]

I don't mean to perpetuate the tangent this thread is taking, but my friend was worried about taking road trips and sleeping in his van close to ULF lenses containing radioactive glass. I arranged for his lenses to be tested by the Director of Radiation Safety at the university at which I work.

IIRC, the radiation exposure you would receive after staring directly into the glass for an hour from ~6 inches away was similar to that you would receive during an hour of commercial air travel. The metal barrels shielded the radiation considerably. The ground glass would probably provide additional shielding while composing as well. In short, the Director told my friend that he should simply limit his close contact with the glass. My friend was reassured.

[Tony Karnezis]

Back on topic: if you're leaning towards 8x10, someone just posted a Rodenstock 300/5.6 for $300.

http://www.largeformatphotography.in...6-bargain-lens

[John NYC]

If you go ahead and search the internet you'll find an article about the AE that pretty much discounts the radiation as trivial. Short of living with it in your pocket it's not going to do anything!

I know exactly how much radiation comes from it.

[genotypewriter]

I would not say that with such surety. Radiation is cumulative. So if you have had or will have other exposures fro other sources, it could be more significant. Also, some people react differently to differing levels.

I would definitely not want one of these in my house, personally.

I know exactly how much radiation comes from it.

I recently had the physics department of the university that I work in run some tests on my 12" Aero Ektar in isolation with significant shielding from background radiation. This was using a calibrated, permanently installed alpha, beta, gamma and x-ray measuring device in a shielded room over an extended period of time. Simulations have also been performed to measure the absorption rates. So it's not done by holding some dude's pocket-sized ebay Geiger counter to the lens and looking at the reading. We've got the results and are in the process of writing a paper on it (the physics folks are doing most of the work so how soon it comes out is a bit beyond my control).

The results indicate that it's not worth worrying about. The alpha and beta can be stopped very easily and the gamma is not bad as long as distance is increased... worrying about the radiation will do more harm than the radiation itself!

But it's still radiation... the less of it you get, the not bad it is It's like driving and speed. The slower you go, the fewer the chances of fatalities in accidents... so is the best thing to do not travel by vehicles at all?

[Tony Karnezis]

The results indicate that it's not worth worrying about. The alpha and beta can be stopped very easily and the gamma is not bad as long as distance is increased... worrying about the radiation will do more harm than the radiation itself!

The only thing I might worry about is bremsstrahlung from betas hitting a dense brass barrel.

But it's still radiation... the less of it you get, the not bad it is

Prudent advice.

[Tony Karnezis]

So, Serge. I'm curious how your thoughts evolving on the topic of 4x5 vs. 8x10.

[John NYC]

The results indicate that it's not worth worrying about. The alpha and beta can be stopped very easily and the gamma is not bad as long as distance is increased... worrying about the radiation will do more harm than the radiation itself!

I am not going to argue with you or Corran about what is safe and what is not. You know why? You two are just theorizing about radiation. I am a person who has a permanent serious health problem directly due to radiation levels/sources that were deemed to be "safe" by all manner of experts.

[Tony Karnezis]

I'm sorry to hear that, John. I don't want to come across as casual about radiation. I simply wanted to put the radiation emitted by lenses in perspective by comparing it to other exposures we willingly and perhaps naively accept as "safe." The more we have learned, the less radiation the medical field uses for imaging procedures. There was a time when X rays were deemed safe by "experts" and used for everything from acne treatment to even sizing your feet in a shoe store. Times have gladly changed, but perhaps not soon enough for you.