Clearing thorium yellowing

guardian · Joined: 18 Mar 2009 Posts: 1749

I just stumbled across an interesting solution. This is proclaimed to be fast:

http://nortega.com/fastest-tool-to-clear-yellowed-thorium-lenses/

kds315* · Expire: 2021-03-09

IKEA JANSJ� is no UV LED lamp, so I wonder how that should work....(if it was it would have to be declared as that just for eye protection).

guardian · Joined: 18 Mar 2009 Posts: 1749

std · Joined: 09 Feb 2010 Posts: 1827 Location: Bulgaria

I do have that lamp - got for reading but it's absolutely not good - the led makes too bright and concentrated spot with cold tone - just terrible for reading at bed Smile

So that may be a good use for it - unfortunately i do not own yellowed lenses Smile

Aanything · Expire: 2014-05-30

I have one of these lamps, and I tried.
I left a super takumar 1.4/50 under the lamp for a week, and I think I saw some improvement.
It was a really little difference, so little that it could also be a mistake.
Somewhere else I read that some cheap LEDs emit also some UV light, and this would be the case.
Anyway, sunlight and uv lamps seem a better solution.

visualopsins · Expire: 2025-04-11

Could be blue light (from white led) also clears yellowing. Wink

I've cleared two Asahi 50/1.4, one Super and one SMC, by leaving rear elements exposed to Skylight for about a week -- Skylight is heavy with UV and much cooler than direct sunshine -- the Super did not clear as completely as the SMC...

Srdjan · Joined: 11 Apr 2012 Posts: 316 Location: Nis

Interesting solution especially if it fast as the author of text say. But what is real purpose of this lamp?

kds315* · Expire: 2021-03-09

Read books

Srdjan · Joined: 11 Apr 2012 Posts: 316 Location: Nis

Does UV light is bed for eyes?
Maybe better solution is go to solarium and bring you lens with you?

memetph · Joined: 01 Dec 2013 Posts: 942 Location: Poland

There is a movie on Youtube on that topic.
I bought the lamp by Ikea.
I think it has improved a little bit one of my Super Taks 55 f1,8
After one week, no change on my Yashinon 50mm F1,7 DS-M which is really yellowish.
Cheap but not very convincing !

ForenSeil · Joined: 15 Apr 2011 Posts: 2726 Location: Kiel, Germany.

As said daylight has multiple� times higher UV content than any normal white LED.
Ikea solution doesn't make sense to me at all. And compared to daylight it's pretty expensive Wink

memetph · Joined: 01 Dec 2013 Posts: 942 Location: Poland

Hier ist keine Sonne ! ( Polen)

Sam Steely · Joined: 09 Dec 2013 Posts: 44 Location: Berlin, Germany

davidblue1984 · Joined: 29 Dec 2013 Posts: 68

[img]

hoping this works! There is a super strong yellowing...[/img]

Lloydy · Expire: 2022-01-01

I just put my yellow lenses on a window ledge for a while, it virtually cleared a Auto Yashinon 50 / 2 very effectively over a few weeks of typical English weather. I don't think strong sunlight is needed. Once the lens is cleared I store them in natural light with no caps and I haven't seen a return of the yellowing.