Dear Lab Guy,

Dear Lab Guy, I tried using your Autoradiography pens on X-Ray film, but I can barely see it when I’m writing it down. Is this normal?

Hi Mike,

Yes, you won’t see it well under normal light which is normal. The markings from SP Bel-Art Autoradiography Pens becomes clear after the X-Ray is developed, or even under a UV light, which is where I shot this photo.

In the image, it was interesting that the fluorescent marker (pictured at the bottom) did not catch at all. I did not expose the writing to a long period of light – the results may have been even starker if I really let the writing sit in the sun. Also pictured is the SP Bel-Art Fluorescent Ruler.

I hope this helped and answered your question. Thanks for writing in, and please feel free to write back if I can help in any other way.

Yours in science, Lab Guy