Originally posted by xinanbei Is it really quality problem?
No, the radioactive glass (not the coating) is a well-documented design characteristic of the lens
Quote: Is is necessary to notify the lens is radioactive when you are trying to sell this.
No...see above
Quote: I haven't seen any description of that from our forum market place.
Not surprising...see above.
Many lenses made through much of the mid-20th century have elements made with thoriated glass. The rare earth element Thorium was added to fine-tune the refractive index of the glass. The radiation was a side-effect. The most notorious were lenses on various Kodak products though a comprehensive list includes lenses from most major manufacturers.
There are a number of Web articles that attempt to quantify the risk, but as noted above, the dosage from even regular use is pretty slight with intensity falling off by the square of the distance. To put it in terms that a photographer would understand...it is not enough to fog film.
As far as your purchaser is concerned, if you have additional conversation you might want to make the following points:
- The price of the lens was very competitive and represents reasonable market value for similar items sold elsewhere
- Retail outlets with similar product post no warning (use KEH as an example)
- If the buyer is dissatisfied with the lens, he/she is welcome at any time to resell the lens with a warning to potential buyers regarding the radioactivity
- There is no moral, ethical, or legal rational or precedent for you to be required to accept a return
Steve
(Has a couple of lenses on the shelf that are reputed to be radioactive...does not carry such in pants pocket...)