De-Yellowing a Pentax 50mm Super Takumar Lens

Using ultraviolet light, you can eliminate the yellow discoloration that occurs in some camera lenses.

Category:

Howto & Style

Tags:

• UV
• Super
• Takumar
• yellow
• Pentax

[markitymarkiemark]

how long should you bath it in the UV a day?

[luketrash]

I had the light on 24 hours per day for a week.

[simonspiers]

I did the same to my 50mm f1.4 and although the glass cleared, the image was the same. Great lens!

[luketrash]

In my case, the image quality is the same, but I gained about 1.5 stops of speed. Which is really what f1.4 is all about ;-)

[dupalopez]

Excellent, I'll try that on my s-m-c tak 50 1.4. Somehow I prefer your UV lamp method rather than "putting the lens on a south-facing window sill for a month" as suggested in many places :)

How long did it take you to get rid of the yellowing?

Absolutely love this lens, even with the yellow cast. When I shoot B/W it's like a yellow filter :)

Big thanks for the tip!

[luketrash]

It took a week for the yellowing to go away. I had the light on 24 hours per day.

[ninjavspenguin]

once cleaned, have you had to clean it again? about how often do you have to do this process? i just got a the tak 50 and I don't want to have to do this all the time.

[ugeironIII]

hi, is that a UV lamp or a Wood lamp (black light lamp is also called...)? does it have a particular power/watt?

thanks

[SuperCrazyStorm1]

Decay of thorium

[robertlam18]

Hi I see a 1.4 in yahoo auction. It says yellow coating. Is it natural or has problems?

[robblac]

I have an old canon FL 1.4 50mm lens with a yellow tinge, I put it tinfoil and lef the rear element open, facing the sun on the window ledge today, i will let you all know it it works.

[arrowcatcher]

I have one of these lens and put it in the sun on a window sill wrapped in aluminum foil except for the rear element. It took several months, but the yellow is totally gone. It was winter, so the sill was never really hot. This UV lamp trick looks like it's much faster. Whatever the case, I can certainly vouch for the concept of UV light fixing this problem.

[wtnssprgrssn]

Thanks for the tip.

Do you happen to know if it matters if you use a florescent tube black light vs a black light bulb? At my local target I was only able to find a 60w black light bulb..

[uyt384]

After 8 days, the darkening was only about 1.25 to 1.3 times more than the AIS Nikkor. The Takumar was actually clearer than an old (1960?) 5.8cm f/1.4 Nikkor-S and an old G. Zuiko 5mm f/1.4 lens, according to measurements -- all looked the same to the naked eye.