Thread: Lens Fungus
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Old 29th June 2016
Ricoh Ricoh is offline
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Re: Lens Fungus

Quote:
Originally Posted by Naughty Nigel View Post
No, but shining torchlight through a lens is helpful for revealing and illuminating fungus and any other contamination. This is best seen by viewing the illuminated lens elements at an oblique angle.
Eyes are not 'designed' (ie have not evolved) to look at light, but to see with (reflected) light.

Normal incandescent light sources are better for the purpose (old style torchlight) and your recommendation for viewing oblquily is the best advise if you must look at a light source.

As for LEDs which emit in the near IR (such as those used for pointing) the retina can be damaged easily - no blink response, or reduced, and focused near perfectly on the retina.

I worked with equipment that emitted in near IR and apart from having to wear eye protection I had regular retinal scans - mainly for the benefit of the company, some suggested!
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