I bought a 'new' lens, a Radioactive Asahi super-multi-coated Takumar 50mm f1.4 - An open thread

Fixer

Fixer

Messages
463
Edit My Images
Yes
It is radioactive and tints everything and is old and is manual focus but wow is it different ! . . . It loves flash lights though and is actually pin sharp in that situation (edge fall off excepted). I like it and will post my photos now and then. Do you have photos taken with one? - post them here so we can compare if you want.

Asahi super-multi-coated takumar 50mm f1.4

https://flic.kr/p/2pFafYq
View: https://www.flickr.com/photos/195125710@N06/53608047928/
 
The 1970's rig . . . A rare-ish Honeywell Spotmatic SPiia a same era camera as opposed the Canon above.

2Y3A4805 by Stephen, on Flickr
 
Here is a SOOC photo - I was surprised at the shallow depth of field as only a few front grill strips are in focus. This is my first and was for a bit fun in the Forum nifty fifty challenge; 'Book' . . . I used this 50mm lens as it is the only 50mm I possess ! (looking forward to more of the nifty fifty assignments now too).

2Y3A4939 by Stephen_Photographs02, on Flickr
 
Fixer said:
Here is a SOOC photo - I was surprised at the shallow depth of field as only a few front grill strips are in focus. This is my first and was for a bit fun in the Forum nifty fifty challenge; 'Book' . . . I used this 50mm lens as it is the only 50mm I possess ! (looking forward to more of the nifty fifty assignments now too).

2Y3A4939 by Stephen_Photographs02, on Flickr
Click to expand...
What’s the watch you are wearing there….?…..looks very nice…!


Cheers:
Peter
 
macvisual said:
What’s the watch you are wearing there….?…..looks very nice…!


Cheers:
Peter
Click to expand...
It is a 47mm homage watch to the Panerai Marina Militare. This watch you see here is my Parnis Marina Militare and has a Seagull movement. Back to Panerai, the Panerai watch was made for the Italian navy back in the day and used either a Rolex movement or an Angelus movement (I have an Angelus watch and it is considered better than Rolex by many). I have worn my Parnis Marina Militare to work and out and about and it is a good watch in my experience. This watch has a display back so the internals can be seen through the clear glass back. It is a pleasure to wear and cost about £190.00 quite a while ago. A real Panerai Marina Militare costs about £7,000.00 ( https://www.collectorsquare.com/en/watches/panerai/luminor-marina-militare/lpi ) . I don't have a real Panerai Marina Militare, but I do have a mint condition 2017 Canon 300mm f/2.8 AF IS USM ii that I use lol !!!!
 
Radioactive Asahi super-multi-coated Takumar 50mm f1.4 @ f16 1/20s iso50. Handheld pan.

What a crazy result !

2Y3A6680 by Stephen_Photographs02, on Flickr
 
Great photographs! Good fun this lens, I haven't used mine too much so I do have a tough time focusing it for 'action' shots. Practice, practice. practice ! I don't have a Geiger counter that works anymore but I am super curious to see how radioactive my lens is. I am aware if the lens is placed under a UV light for several days the colour tinge will clear, but I like mine with the tint. Anyway, welcome to the club and feel free to use this open thread as you wish. Just to note I remove the lens from my camera body as soon as I have finished my shoot.
 
RyanB said:
I picked one of these up on Friday for peanuts as it had fungus on pretty much every element. Manged to clean all but one which requires a bit more of a breakdown than I wanted to get into today but I got out just before dusk to have a play with the neighbour's pigs.


f2
View attachment 430860

f4
View attachment 430861
Click to expand...
For a fungus filled lens that is sharp as a whisker.
 
That's because the radioactivity has mutated the fungus into whiskery hamsters!
 
Fixer said:
Great photographs! Good fun this lens, I haven't used mine too much so I do have a tough time focusing it for 'action' shots. Practice, practice. practice ! I don't have a Geiger counter that works anymore but I am super curious to see how radioactive my lens is. I am aware if the lens is placed under a UV light for several days the colour tinge will clear, but I like mine with the tint. Anyway, welcome to the club and feel free to use this open thread as you wish. Just to note I remove the lens from my camera body as soon as I have finished my shoot.
Click to expand...
Thanks, I too have been curious as to its actual radioactivity as there is a lot of speculation and guessing amongst the info floating about the web. I have seen you can pick up a cheapo Geiger counter for around £20 but for that kind of price it surely can't be accurate, maybe I'm wrong and it could be worth a punt to see what it reads.
Mine has the browning core on the third from the rear element which is also the difficult to get to one I still need to clean the fungus off of, probably good to know how hot it is before removing and cleaning it by hand. By most online accounts using gloves should be enough to protect but without the other glass elements and metal from the lens surrounding it, its about as close contact as you can get.
GreenNinja67 said:
I certainly wouldn't put it in your trouser pocket.
Click to expand...
No probably not a great idea, could hurt knocking against my junk. It certainly isn't comfortable under my pillow at night... ;)
Terrywoodenpic said:
For a fungus filled lens that is sharp as a whisker.
Click to expand...
Centre sharpness is actually better than I thought it would be for a lens of its age, even at f1.4 although the DOF is razor thin. It was spider webbed throughout the elements and some initial test shots were a bit dreamy looking. Cleaned up ok though except for one surface of a single element which only has minor fungus webbing so optically its pretty good. Just want to get the last one done so it doesn't spread again really.
Nod said:
That's because the radioactivity has mutated the fungus into whiskery hamsters!
Click to expand...
Just don't get them angry, you wouldn't like them when they're angry...:p
 
I understood that it was only certain Takumar lenses that contained thorium, but I have some pretty standard 50's that have a distinct yellow cast, so I'm not sure now.
 
Plain Nev said:
I understood that it was only certain Takumar lenses that contained thorium, but I have some pretty standard 50's that have a distinct yellow cast, so I'm not sure now.
Click to expand...
Evidently a yellow cast could be a coating not necessarily a thorium element. From what I have read one or more of the elements develops a darker brownish/ yellow core with lighter edges which is a tell-tale sign of the radioactive element. That is certainly what mine looks like and is listed as one of the confirmed radioactive versions on various sites although they all seem to be user contributed data sets so claims should be taken with a grain of salt like with Wiki pages.
 
I had one of these. I liked the tones and colours it gave for people pictures.

I think this was my favourite "picture" taken with mine, it's a panorama, I forget how many stitched pictures.

Pan-Saltburn.jpg
 
Oddly enough, I was thinking this morning that I’ve seen a couple of mentions of “my radioactive lens” on here recently, and was wondering who had posted it because I wanted to find out more!

I’ve just read through that link above: so is the thorium just to improve sharpness? @Fixer you mentioned taking it off your camera straight after use: do you have to store it away from your other lenses?

Final question for now: does the yellow cast make it good for black & white work?
 
skullfunkerry said:
I’ve just read through that link above: so is the thorium just to improve sharpness? @Fixer you mentioned taking it off your camera straight after use: do you have to store it away from your other lenses?

Final question for now: does the yellow cast make it good for black & white work?
Click to expand...

The main reason to use thoriated glass was that it provides a higher refractive index than regular glass; that made the elements smaller and lighter, allowing more complex designs more practical to manufacture.

It also offers lower dispersion (like more modern ED glass) so fewer chromatic aberrations and a sharper image.

I have a 1970s Canon FD 35mm f/2 SSC with thorium glass and, yes, it is great for black and white work. It’s like having a permanent yellow filter without the extra layer of glass and it’s already a very sharp lens for its era.
 
Plain Nev said:
I understood that it was only certain Takumar lenses that contained thorium, but I have some pretty standard 50's that have a distinct yellow cast, so I'm not sure now.
Click to expand...
You are correct, many 'tinted' lenses are not radioactive. Some Olympus lenses were like that I have read, somewhere!
 
skullfunkerry said:
I’ve just read through that link above: so is the thorium just to improve sharpness? @Fixer you mentioned taking it off your camera straight after use: do you have to store it away from your other lenses?
Click to expand...
It has been suggested the continued radioactive emissions from the one thoriated element in the lens is not good for the electronic sensor of the camera. I don't know if this is true but I surely don't want to find out lol !

The thoriated glass reduced chromatic aberrations so one less element could be used making the lens production faster and cheaper and the lens lighter (so they say).
 
Last edited:
This is a good little video too.

View: https://www.youtube.com/watch?v=sG_69I45H2k
​


And just For Your Information I paid £120.00 for my Radioactive Asahi super-multi-coated Takumar 50mm f1.4, mint and a collectors piece as it was unused. It is used now however, for the Gav. Nifty Fifty challenge 2024 :pompous:
 
Musicman said:
The main reason to use thoriated glass was that it provides a higher refractive index than regular glass; that made the elements smaller and lighter, allowing more complex designs more practical to manufacture.

It also offers lower dispersion (like more modern ED glass) so fewer chromatic aberrations and a sharper image.

I have a 1970s Canon FD 35mm f/2 SSC with thorium glass and, yes, it is great for black and white work. It’s like having a permanent yellow filter without the extra layer of glass and it’s already a very sharp lens for its era.
Click to expand...
I believe it used to be used to increase contrast in medical radiology so may also have a similar effect in optical systems.
 
You must log in or register to reply here.
Back
Top