NickTrop
Veteran
Recently acquired a "cheap pick-up" of an M42 Pentax Super Takumar 50mm F1.4 probably do to it having "yellowed" some due to the fabled radioactive element in the rear of the lens.
I don't think my sample was as bad as some I'd seen but it was definitely there. We've experienced excellent sunny weather where I live - mostly, over the last week, week and a half and I set my lens out on a deck table from morning until night for some sunshine. Most of it seemed to clear up within the first 3-4 days of treatment, and it was "all" gone (to my eyes) in a week or so. This lens is perfectly clear and free from any yellowing now. I think I really helped speed up the process by setting the lens front down on a sheet of aluminum foil with the rear element facing the sun and the aperture wide open at f1.4 to maximize the reflection of the UV rays off the foil back through the lens.
So, if you pick up a yellowed radioactive lens, this trick ain't a rumor. It absolutely works. At least as far as the 50mm Tak is concerned.
This is a very nice lens by the way. Beautifully constructed with a smooth, a tactile pleasure to use, silky focusing ring - hands-down the best I personally ever owned. It also reminds me of my Summar in terms of how it renders images - especially the "abstractness" of the out of focus areas. Never owned a Leica Cron - but if someone told me some of the pics I took with this Tak were taken with a Cron, I wouldn't question it for a second. This is a Summar that's a bit sharper with higher contrast but has that wonderful "painterly" bokeh I love with the Summar. But the Summar still has a way of rendering a better overall 3D look and a pleasing "strangeness"(?) (for lack of a better word) to the images it captures than this lens.
That all said, I must say that I've come to appreciate the 1.4 on my Lynx 14 now that I have a basis for comparison. Both perform in "real world" applications (as opposed to MTF charts, I'm guessing) about the same aperture for aperture in terms of sharpness. They paint scenes differently and I'd have to give a slight edge to the Tak here for its Leica-like qualities, warmth, and better flare control. However, it certainly doesn't "blow away" the Yashica lens by any stretch - and for low light/hand-held shots, the Lynx because it's a rangefinder just performs much better at much slower shutter speeds. You just can't do as well with an SLR.
I don't think my sample was as bad as some I'd seen but it was definitely there. We've experienced excellent sunny weather where I live - mostly, over the last week, week and a half and I set my lens out on a deck table from morning until night for some sunshine. Most of it seemed to clear up within the first 3-4 days of treatment, and it was "all" gone (to my eyes) in a week or so. This lens is perfectly clear and free from any yellowing now. I think I really helped speed up the process by setting the lens front down on a sheet of aluminum foil with the rear element facing the sun and the aperture wide open at f1.4 to maximize the reflection of the UV rays off the foil back through the lens.
So, if you pick up a yellowed radioactive lens, this trick ain't a rumor. It absolutely works. At least as far as the 50mm Tak is concerned.
This is a very nice lens by the way. Beautifully constructed with a smooth, a tactile pleasure to use, silky focusing ring - hands-down the best I personally ever owned. It also reminds me of my Summar in terms of how it renders images - especially the "abstractness" of the out of focus areas. Never owned a Leica Cron - but if someone told me some of the pics I took with this Tak were taken with a Cron, I wouldn't question it for a second. This is a Summar that's a bit sharper with higher contrast but has that wonderful "painterly" bokeh I love with the Summar. But the Summar still has a way of rendering a better overall 3D look and a pleasing "strangeness"(?) (for lack of a better word) to the images it captures than this lens.
That all said, I must say that I've come to appreciate the 1.4 on my Lynx 14 now that I have a basis for comparison. Both perform in "real world" applications (as opposed to MTF charts, I'm guessing) about the same aperture for aperture in terms of sharpness. They paint scenes differently and I'd have to give a slight edge to the Tak here for its Leica-like qualities, warmth, and better flare control. However, it certainly doesn't "blow away" the Yashica lens by any stretch - and for low light/hand-held shots, the Lynx because it's a rangefinder just performs much better at much slower shutter speeds. You just can't do as well with an SLR.
MikeL
Go Fish
Great tip Nick,
I did this about a year ago, with foil, and it worked like a charm. Before I did it the lens almost looked orange. I just picked up a summar.....
I did this about a year ago, with foil, and it worked like a charm. Before I did it the lens almost looked orange. I just picked up a summar.....