Welcome to our community

Be a part of something great, join today!

Log in
  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

P&S Cooke Speed Panchro De-Yellowing

Chad Stockfleth

Chad Stockfleth

Well-known member
Joined
Sep 4, 2013
Messages
95
Reaction score
0
Points
0
I've got a set of TLS rehoused Speed Panchro's. Love them. The 75mm has the yellow tint that a lot seem to have. TLS doesn't offer a de-yellowing process, but P&S Technic does. Anyone have experience getting this done? I'm wondering how drastic the results are.

Thanks,
Chad
 
I bet it works great!

If I were to venture a guess they probably use a high power UV lamp exposure - you could try to DIY something similar like this:

http://amzn.to/2ewvU2o

No idea if this would potentially damage other things or cause Grease to run/melt... just throwing out ideas.
 
At your service, Jacek!

the whole hard UV process works for those lenses which have radioactive (Thorium) or/and rare earth elements (Lanthanum) in the glass or in the coating, Сooke SP ser.II among them, also Zeiss' lenses of 1950-70 era. As for Japanese Takumars (and other models), we all know it.
 
Bryan Koss said:
Has anyone performed a successful procedure of "de-yellowing" vintage Cooke Speed Panchros with a UV Light?
Click to expand...

Not that I'm aware of. I've just started experimenting with de-yellowing my TLS Cooke 75mm SER II as P&S charges about $2k to remove the yellowing.

So far I've tried the Ikea Jansko light everyone talks about and had no luck. Next I'm going to try UV-B CFL bulbs designed for reptiles and then sodium mercury as described above.
 
Hello,

I'm currently deyellowing a Cooke 75mm SPII which was very warm with this 365nm torch lamp from Amazon: https://www.amazon.com/dp/B07KT6ZSWV/ref=cm_sw_em_r_mt_dp_U_CGTiFbCJF9MSR

It does seem to work but it's slow, very slow, weeks to months of exposure I would say.

I did plug it on USB power, removed the battery and use a little bit of diffusion in the front to make the beam from the leds more even (less output for sure). I use silver foil on the opposite side of the lens and switch the source from front to back every week or so.

I had success on Canon FD lenses (the 35mm F2 concave and 55mm Asph 1.2) with the Ikea lamp. It didn't seem to work as well on the Cooke.

All the best,

Olivier
 
If anyone is still looking at this thread, I can say Olivier Boonjing's method for de-yellowing the 75mm Cooke Speed Panchro worked for me.

I purchased the same torch lamp https://www.amazon.com/dp/B07KT6ZSWV/ref=cm_sw_em_r_mt_dp_U_CGTiFbCJF9MSR
I took out the blacklight glass in the front and used a mirror on the bottom and a clear filter on the top and just sat the torch on the filter shining straight through. Plugged in through USB same as olivier, rotated the ends after a week each side. I just compared the 75mm to the other lenses against a white wall, its now less yellow than the 40mm and 50mm... looks same as the 25mm and 32mm. I'm now doing the same process with my 50mm.

Thank you Olivier for your tip! Appreciate you sharing it.
 
Hi guys,

I just de yellowed my old Speed Panchro 75mm. It was very warm, and I just checked the image after 24h and it’s much cooler.
I am really impressed with this technique. Thank you very much for sharing. It really works. I am going to do 40mm now. That is just bit warmer.

Ivan
 
You must log in or register to reply here.
Back
Top