Radioactive Lenses Part 3. Why the lenses are so good, lists, and yellowed glass - keep or cure?
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- เผยแพร่เมื่อ 3 มี.ค. 2021
- This video looks at the positive side of radioactive lenses: why they were made, who made them, and the pros and cons of yellowed radioactive glass.
It also explains some quirks and surprises in lists of radioactive lenses. - วิทยาศาสตร์และเทคโนโลยี
Am I really the only gen z person between all these bommers? Nevertheless I really enjoy your soothing voice and accent. Your channel is truly a gem that I am grateful for to have found. I find your videos quite interesting and really informative. That’s the kind of quality content that should be more present on TH-cam. Big props from Germany!
I was born in 1981, probably closer to your parents and I applaud young People who take time to study products from the past and have the wisdom to understand that older generations were as skilled asit gets hand crafting some of the best products ever made. this is especially true with film lenes, where it is amazing to think that someone hand shaped every component with a mind boggeling degree of accuracy with incredibly tight tolerances Often times in most extreme conditions (ie Germany and Japanese lens and watch makers during WW2).
Also, I think the reason that older users prefer these types videos is because they can remember some of these lenes with their old film cameras.
Plus Simon is a knowledgeable professional with a great narrative tone, who obviously takes pride in producing high quality content.
Having knowledge and respect for the past will provide you with a substantial advantage over others in your generation, who think the world began in 1990!
Well I'm not sure what gen I am but I was born 2001, and I really appreciate this type of content.
I’m from 2004 and you’re not the only gen z person. ;)
Another Gen Z here! 2003. Very grateful for Mr. Simon and his videos. I love my SMC Takumar 55/1.8. So creamy for so little (~$50).
Here at 22!
Yippee! Part Three. I haven't even watched it yet but know for sure it is gonna be good. Thanks for putting this series together Simon, it really has been very informative. I may add more when I have watched it but the excitement of seeing it in my list got the better of me.
I know your focus (ahem) is usually on the 50mm range, but you can find some interesting wide angle radioactive lenses too. I've got 2: the Super Multicoated Takumar 35mm f/2 and the Minolta MC SI 28mm f/2.5. The 35mm Takumar is really sharp but quite yellowed, and I've been temped to cure it. The Minolta is center-sharp, but breaks down at the edges, though it maintains far far more linearity in straight lines than other contemporary 28s. I should also note that there is another way to check if your lenses may be radioactive, if you lack a geiger counter. Take a 30sec (or longer) exposure with the lens cap on, at ISO100, and with any noise reduction turned off. Pull up the RAW file and if your lens is radioactive, you'll find white pixels. The more hot pixels you see, the more active your lens is.
Thank you Simon for another informative posting. Good to know which lenses are radioactive and why the manufacturers choose to make them so. Excellent post as usual.
Very nicely done. A worthwhile 3d video on the topic of radioactive lenses.
This is a great series. I recently discovered your channel while researching vintage lenses and I enjoy watching your videos. And your channel name is awesome!
Thank you!
Really appreciating your videos! Recently picked up four Super Takumar lenses in great condition, a 24mm f3.5, 35mm f3.5, and two 50mm f1.4 (one is the super multi coated). Been watching your channel all week and loving all the info
You're very welcome. Enjoy those lenses!
I love the golden hue in my first 8 element Super Takumar 50mm 1.4. As it happens, I lucked into another without any discolouration. I am delighted, because the question of de-yellowing no longer mattered. If I had a real brown 7 element version, I would clear it without question. Another great video!
Thank you! I'm still thinking about de-colouring my SMC Takumar 50mm f1.4, its rather dark. And I suspect less sharp too.
Really fascinating and informative series Simon. Thanks for all that useful info
My pleasure!
Hello.
I regularly watch your videos. Very well done and very useful. Thank you!
I love historical information.
Another great video Simon!
Superb content as always
Quite an interesting series on radioactive lens
Shocked to see that my beloved Pen F. Zuiko 38mm f/1.8 is probably radioactive. It's clear as day (and a real beauty of a lens). While I knew my yellowed S-M-C Takumar 55mm f/1.8 is likely radioactive, it never even occurred to me that the Zuiko might be until I happened to spot it in the scroll through the camerapedia list. Needless to say, it will be moved from its usual spot in the corner of my room, about 3 feet from where I sleep.
Another informative video. Keep them coming! Thank you
Thanks, will do!
Another very enjoyable video !! I just store my radio active lenses in a plastic container with a clip on secure lid with lots of foam in the box to stop the lenses from moving or risk of breaking from dropping the box and radiation isn’t an issue with my Geiger counter next to the box a few inches away!
As always very informative and well researched. Worth watching many times over. Interesting that some lenses had different components during their production cycle. I have the SMC Takumar 50mm f1/4 and it is quite yellow, I enjoy the autumnal tones and won’t be removing the yellowing. My solution is to purchase a newer K-mount 50mm that is non-radioactive.
Thank you for your kind words. We're lucky in the k-mount and M42 world to have so many excellent fast fifties - yellowed and non-radioactive!
What non radioactive lenses that are vintage you have?
Another great and informative video. I just won a bid for both the super takumar 50 1.4 (7 elements) & 50mm macro f4, cannot wait to use them. I'm really not sure if I'll want to de-yellow my glass or not.
Two great lenses - I guess you'll have them with you now. It may depend on how yellow they are. My much loved Macro Takumar 50mm f4 shows no signs at all of yellowing, but if it did, I'd cure it immediately. Tougher decision with the S-T 50m f1.4. Such a good lens anyway, and hopefully yours is not too yellowed. Have fun with these lenses!!
I have the Super Takumar 55mm 1.8 and it is radioactive. Thanks for the great vids.
Fantastic info!
Glad you think so!
Se tutti praticassero più meditazione, anche solo pochi minuti al giorno, questo sarebbe un mondo migliore. Grazie per il messaggio ❤
Dropped on your channel a few weeks ago and really enjoying watching .... funny though at first i thought you was english until you mentioned thrift shop and other American sayings..... anyway first class material Cheers
Like legacy lenses this channel should age well.
Exactly. I found myself keep referring back to the videos here and always able to discover some good points I missed in the past.
Several lens manufacturers in the 1960s were looking for ways to create new types of glass with a high refractive index and a low chromatic aberration. They started to use rare earth compounds, such as fluorite and quartz, even radioactive thorium dioxide (ThO2). Quartz and fluorite are quite expensive and hard to produce. For other lenses they added small amounts of thorium dioxide to the glass, but only in the rear or front lens group. The radioactivity (alpha radiation) of the thorium dioxide may cause self-degradation of the glass (turning it brownish yellow over time). Not all lenses turn yellow, however.
Alpha radiation is effectively shielded by a few centimeters of air, paper or the thin layer of dead skin cells that make up the epidermis, so it is not particularly dangerous. The rear cap of the lens will block most of the radiation effectively and there is no danger of fogging the film or damaging the sensor in a digital camera.
Radiation levels are stated in microsievert per hour (μSv/h). A set of dental radiographs will expose you to approx. 5 μSv of X-rays. If a lens was to emit 5 μSv/h, it would generate the same dose of alpha radiation in 1 hour.
2:24 - I was surprised to hear that some people were calling Lanthanum radioactive - I've been teaching geochemistry for many years and supposedly the only radioactive rare earth element is Promethium, and there's not much of it around anymore since all of its isotopes are radioactive with short half-lives and have decayed to nothing long ago. So I looked it up - yes, Lanthanum does have a radioactive isotope (La-138), but it has a half life of about 10^11 years. Which means it's hardly radioactive at all, and it only makes up 0.09% of the element. Compare that to Thorium - 99.8% of it is Th-232, which has a half life of 1.4x10^10 years - again, not VERY radioactive, but it's still about seven times more radioactive than La-138, and there's a great deal more of it in the metal. I'm not surprised they were using Thorium in glass, it's well known that heavy metals such as Lead increases the refractive index of glass - the term "Crystal" was used for glass containing Lead, and used to make costume jewelry, chandeliers and such (they've probably replaced the Lead with other substances - maybe barium - these days). One wonders what else they use in camera lens glass besides Th and La - there are lots and lots of heavy metals to choose from (including depleted Uranium, of which there is plenty, and which is less radioactive than common Lead). One also wonders what causes the yellowing of the glass - my first guess is fission tracks (though one wonders how much spontaneous fission actually takes place with Thorium), or it might be damage caused by alpha particles. Whatever it is, it seems to be healed by sunlight. Incidentally, Potassium (which you find EVERYWHERE) is significantly radioactive. Look up "Banana Equivalent Dose" sometime.. 😁
Thank you for this informative series of 3. I am now pretty sure that I don't own any radioactive lenses. A few has a yellow tint, but they are not listed anywhere as radioactive. My Pancolar 50mm 1,8 is of a newer generation but still is faint yellow. Maybee I won't get any in the future either. My wife was listening to the second of the 3 in another room and was rather worried :-) Well I am trying to avoid them anyway. Since you had some surprises I should maybee test them myself?
It's fun to test the lenses and other objects (even though I've yet to find anything in the house where the CPM starts to increase).....but privately!
I own four Super Takumars which may be radioactive. Since I've had three of them for about 50 years and haven't come down with any form of cancer yet I assume my exposure to them under normal circumstances is not dangerous. One, the 35mm, has definitely gone yellow over the years - to the point where post-processing is necessary for accurate colours even with auto white balance on in the camera - the others have not. As it is I prefer to leave the one alone and let it make images with "wrong" colours as they come out looking like old film photos might.
The fourth, a 135mm f3.5, was a recent acquisition in a group of 10 old lenses I picked up quite cheaply that also included a Helios 44/2. That lens is the epitome of your contention of how 'Internet fame' can drive up the prices on vintage glass as around here people want $100 or more for one now. Glad to say I didn't pay that much for the whole lot!
Surprised to see the Nikkor AIS 85mm f/1.4 on the camerapedia list. I've owned this lens for a few years and had no idea it was radioactive as it doesn't have a yellow tint.
I would not be surprised if you found out that your lens is not radioactive...the page is a collection of nonsense. I have a few Nikon lenses and none of them is radioactive.
@@patriziodalessandro1693 that Nikkor part of the list was indeed later struck out, as these were not measured by a contributor to that page, as intended for the list -- but by a certain yt channel and apparently with a bunch of commenters on that very vid saying they cannot replicate the measurement w their lenses.
Bravo!
My radioactive lenses are:
Asahi Super-Multi-Coated Takumar 55mm f1.8 Radioactive 750 CPM
FUJINON 50mm f1.4 Radioactive 3860 CPM (Hot! Hot! Hot!)
Asahi Super Takumar 50mm f1.4 Radioactive 2250 CPM
Olympus OM-System Zuiko MC Auto-S 50mm f1.4 Black Nose Radioactive 460 CPM
Auto Mamiya Sekor 55mm f1.4 with M42 Mount TOMIOKA Design Radioactive 460 CPM
Olympus OM-System G.Zuiko Auto-S 55mm f1.2 1974 Radioactive 3389 CPM
Minolta MC Rokkor-PG 58mm F1.2 Hawk Eye MF Lens MC II 1967-72 Radioactive 1246 CPM
All great lenses.
The yellow glare you see in some lenses is actually the coating. You need to look through the lens against a white background to check whether the lens has yellowed!
Excellent point - I have a few lenses with yellowed/looking glass that I was convinced are radioactive. but they're not. To take one example - this Auto-Takumar 55mm f1.8:
www.flickr.com/photos/95859572@N06/34065608621/in/album-72157679729369983/
BTW - I wish I'd asked you to sign your book when I bought it!!!
@@Simonsutak I would gladly have signed it for you!
Aw man, I didn't know the Takumar Macro 50mm f4 1:1 version was radioactive!! Oh no I was just looking to pick up a copy of it ! Sheeeesh such a good lens though.
A great collection on the subject, thanks for sharing your experience Simon.
It depends on the lens. I have a radioactive pancolar and when yellow it did not seem to effect the sharpness and rendering. I have a radioactive Minolta 28 f/2.5 and curing the glass helped with sharpness. So in certain cases it appears the yellowing can effect the lens in more than just color. The Minolta cleaned up super quick. The pancolar was extremely stubborn.
Good to know, as I often think about de-yellowing the Pancolor, and from your experience it doesn't seem necessary.
@@Simonsutak The problem is that is based on my sensor. It's possible with a higher MP sensor it may be necessary. The yellowing probably changes the properties of the glass. As long as you are getting results that make you happy I wouldn't change it or find a friend with a de-yellowed Pancolor to compare.
I periodically shine UV light through all my lenses. Not to remove yellow (I also shine through clear glass lenses) but to ensure that fungus does not grow, or if it exists, to kill it so it stops growing. If I discover a lens with fungus in it, I always shine UV into it for several hours so that when I disassemble it to clean it no spores will get loose into my camera room.
hi Simon, very interesting videos, the thing is I recently bought 2 teleonconverters a Vivitar 2x-3 and a Rokunar mc7. I Know they are old i dont know how old though. I have been searching for info but i couldnt find anything. I read about that we have to think every lens concstructed between 1940 and late 70s were made with thorium meaning most of them (lenses constructed in that period fo time) are radioactive, I dont know if that is true or not and if is the same thing with teleconverters. I have a friend with a Geiger counter and im gonna know for sure if they are or not, at least i didnt notice any brown or yellow color in the cristals at first glance (but now with your info i know tht they could be clear and radioactive or yellow without radioactivity), I used the two TC togheter to multiply by four my 600mm lens for moon images and I think I left them attached to the camera for a couple of nights, but worries me the most is I spent like 15 minutes taking pictures of the moon with those two teleconverters attached to the camera. So i dont think they are, or the truth i really want to think that they are not radioactive. At least in the list of radioactive lenses in cameropedia, there weren't any teleconverters of any brand at all, but there are some vivitar lenses, so I dont know if none thorium teleconverter were built (for some particular reason) or maybe there none in the list because no one has tested yet. Hahah i dont know but i want to know, so in a couple of hours im gonna test them with the Geiger but my friend told me that he has never been able to measure anything radioactive yet (I dont know if his geiger is not sensitive enough, it is defective or is working as it should, I hope it is working and my test will no be different than previous ones he has done, hohoho. So any tip if you read this before I test them?
Greetings from Temuco, Chile!
Great review enjoy it very much. I have an Exakta mount Flektogon, M42 Meyer Oreston, and an M42 Mamiya 55mm f1.8 all tested radioactive. Interesting the Pentacon (Oreston replacement) 50mm is not!
I have two CZJ Flektogon 35mm (2,4 and 2,8), and two Meyer Optik Oreston 50mm f/1.8 (zebra v.1 and zebra v.2) and none of them is radioactive - at least, not more than by background...
@@patriziodalessandro1693 very interesting. What were your serial numbers. I have two Exakta 35mm Flektogons and both are definitely alpha emitters
@@py1824 Flektogon Electric MC s/n 10260335
The other s/n 9116058
I am sorry - I did not get the part about alpha emitters...how did you measure that?
@@patriziodalessandro1693 Many thanks interesting to see the variation in manufacture over time. My Exakta's pre-date yours. I used a standard geiger that measures only beta and gamma radiation. Therefore, to have measured radiation some thorium has degraded over time.
@@py1824 Yes. A good guess would be 70-71 for the first one and probably 74-75 for the second one.
And yes. Thorium will continue to degrade for some very long time...
One great lens that I have in my collection is the Canon 35/2. great sharpness but very heavy lens.
Ill preface by saying im neither a camera nor lens guy, but i am a firearms collector. The question of curing the yellowing is much the same question of refurbishing an old firearm. Do you want to experience the lens as it is now: a lens that has seen the passing of time and has particular quirks because of it, or do you want to experience it as it was when it was new? I dont think there is a right answer, or, perhaps, both are correct. I lean more towards things like cameras were meant to take pictures, they have a persistent vitality intrinsic to their function and letting them perform their function is a very direct connection to the past and the people that made it all possible.
Many thanks for your comments. It’s interesting reading about refurbishing firearms. Refurb enough to make them safe or back to more than that? It reminds me also of the debate in classic car community - do you restore an old car to ‘concourse’ condition or do you undertake just enough repairs to make the car safe to drive but retaining all the ware and tear? This means that the engine probably lacks the power it had when new, the suspension is poor etc etc
Personally, I’m more of the opinion these days that I should de-yellow my lenses so they perform as originally intended. But then I miss the yellowing effect!
Have a Super Takumar 85 f1.9 with Thorium front glass, not sure how radioactive? Love it regardless, sharp lens.
I tested my S-T 85mm f1.9 lens at the back and the counter didn't register any radioactivity. I'll test the front too, and report back if it turns out to be radioactive. (Yes, it's an excellent lens - I tried the 85mm f1.8 first, but sold it and kept the f1.9).
I’m thinking that if a lens is yellowed and it comes from pre multi-coating era, it is likely to be thorium. I search out a great many lenses and some glass appears VERY yellow in either reflection and/or transmission. Excellent examples are the early canon lenses with M39 mounts. It becomes more guess work identifying thorium when various multi-coatings arrived. I’ve read that various materials were added to the surface by introducing them as gases or particulates which bonded to the surface. They cut down on refraction and lessen any reduction of overall light as it moves through different densities of material. I haven’t done any research on what the specific coatings are, but they seem to have experimented with many materials as the range of lens surface colours include all colours of the rainbow. Are multi-coatings the only confusing factor as to identifying yellowed thorium, or were there other forms of glass introduced? Skipping over, cured glass of course.
Interesting. I've often wondered about the difference between radioactive glass, where the materials are baked into the glass, versus the coatings on top of the glass. I don't even know whether one can take a sharp flat blade and scrape off the coatings...and measure the radioactivity of this scrapings. But I'm not going to try!!
@@Simonsutak lol - I recently bought a canon LTM that had fungus - obvious in the photos - it was the only way I was going to get a copy of the lens that wasn't going to break the bank , and I was expecting to attempt cleaning it.. I got it the other day and the fungus was literally just on the front element and I cleaned it off with seperate cleanings of Hydrogen Peroxide, Isopropyl Alcohol, Eclipse and lastly lighter fluid - these might all sound crazy to the uninformed but they are all used in videos I watch by mikeno62 .. if you want to fix or clean.. he is one of the best to learn from.. highly recommended. Anyway.. it cleaned up perfectly. So awesome. In doing my research I found some super scary people posting videos on cleaning fungus and haze that explained so much of why some lenses can look like steel wool was used to "clean" the lens. They were painful to watch indeed. Like darwinism for lenses .. seriously. I'll leave those coatings attached to the glass.. your comment brought a shiver to my spine.
To see if the glass actually is yellow and it's not just the reflection of the coatings you need to look through the glass with a white background. This is the best way to tell.
Also I read this recently, and I have not verified it yet. It is that the yellowing is due to a phenomena is called F-center (Color center). Interesting to read about.
And everyone please be careful when placing the lens in the sun. If it gets too hot lubricants can evaporate and end up on the glass surfaces. I have seen people make shades of aluminum foil to direct the light to only the glass and not the body.
My radioactive lenses are:
Meyer Optik Görlitz Primotar 50mm f2.8
Pancolar 50mm 1.8
Macro Takumar 50mm f4
RE GN Topcor 50mm 1.4
Super Takumar 50mm f1.4
Super multi coated Takumar 50mm 1.4
Zuiko 50mm 1.4
Zuiko 55mm 1.2
I really like the Pancolar.
Nice collection of lenses! Yes, that Pancolar is a top lens. And very good advice about leaving a lens in the sun. The lubricants, plus the glass acts as a magnifying glass to burn things in its way. The Ikea lamp, by the way, does not emit a lot of heat.
@@Simonsutak They are all fun lenses to use! How long does take with the lamp for you to clear a lens?
I put one of my Pancolars under the Ikea lamp for 3 weeks and there is still some yellow left.
Hi Simon,
Nice video. I have Ashahi opt. Co lens serial 558120 auto takumar
1:2.2/55.
Would this lens fall in the catogory as being radioactive?
Simon do you have any video about the Yashica 50mm 1:2 lens's radioactivity?
My Takumar 50mm1.4 7 blade lens M42 mount my favorite 50mm lens. I leave my autofocus Pentax 50mm 1.8 at home and take the Takumar
Thanks for the insightful video. I have a few vintage lenses from my grandfather and his father. Would you know whether the Vivitar 28mm 1:2.5 auto wide-angle is radioactive?
Thank you! I'm sorry - I don't know about the Vivitar.
I've got a Mir 1-B (V) 37mm 2.8, and I would like to know if it is radioactive too. I can't find any information about it, and some people says it is not made with those materials. However, it has a yellowish look that makes me doubt. It is probably the coating layer, which is announced to be covering lens. Do you know anything about this lens? Have you tested it? It would be a real relief to know a certain answer. Thank you!
Hi Simon do you know how long does it take for the glass to turn yellow?
Thanks for a very interesting and informative video. I pressed liked and also got rid of the 666 number of previous likes!
I just bought my 2nd Olympus OM-System G.Zuiko Auto-S 55mm f1.2. My first one was radioactive, but my second one is not or at least not much if any. Here are the results of my measurements. I am wondering if anyone knows the history (SN) of the radioactive ones?
Olympus OM-System G.Zuiko Auto-S 55mm f1.2 1974 SN 117492 Radioactive 3389 CPM
Olympus OM-System G.Zuiko Auto-S 55mm f1.2 1974 SN 135479 NOT or (lightly maybe? Lanthanum?) Radioactive
I have a question that is bigging me for a few years now. I have the Yashica 50mm 1.7, the radioactive one. First one I got, had the yellowing, was used (so exposure to uv), had a more recent serial number. I've sold it and got another one brand new in the box. This one was older, had no yellowing even though it had never seen the light of day. Could this one not have the Thorium glass ? Because it's an earlier version (at least based on the serial number), also the non exposure to uv light + age should mean more yellowing. Any idead if this one has normal glass ?
I'm sorry, I don't know the answer. The only way you'll know for sure, if nobody else knows, is to try a Geiger-Muller Counter. I do own two lenses (Super-Takumar 50mm f1.4) where the earliest version does not have radioactive glass, but a later version does.....but this has nothing to do with the Yashica. BTW, my radioactive Yashica DS 50mm f1.7 is a fine lens!!
At 08:41 you talk about leaving the lens in the sun...
NEVER DO THIS!
The lens will get too hot due to the infrared portion of the sunlight. As a result, the grease melts and you may get sticking aperture blades. It also is bad for the "glue' between the lens elements.
Using a Jaslo light from IKEA works fine. Put the lens with covers removes face down on a mirror and turn it after every few hours.
I have done it with no problems, just wrap the lens in foil to cover the black parts as this is what gets them warm and the bottom to reflect the sunlight back into the elements, make sure the aperture id fully open, have done it to 20 lenses and no issues whatsoever if you do it correctly, also the UV kills and viruses if present or about to start and removes any moisture in the lens, tried and tested
@@bern047 I prefer to take no risk. Wrapping the lens doesn't prevent IR light (=heat) to enter the lens and heating it up from the inside. It is a bit like people running a car for 100 000 km without an oil change. It may work...
Just curious.... For the yellow glass that does not emit radiation, would UV exposure still remove the yellow tinting?
Does anyone know if the Canon 50mm 0.95 Dream Lens is radioactive? There is no information about this lens. However, the 50mm 1.2 LTM original advertisement in the late 50’s state it had rare earth materials, which could mean radioactive materials were used.
The near contemporary Canon FL 55mm f/1.2 is definitely radioactive. I've not seen anything on the Dream lens, but I wouldn't be surprised to find it had thoriated glass too.
Thank you for a really informative video, are radioactive lenses harmful to the eye when used on the cameras they were designed to fit, i.e. 35mm film cameras?.
I don't think they are. The problem would be if the camera viewfinder glass itself had radioactive glass and none of my old film cameras have this.
I have recently purchased an Auto Rikenon 55mm f1.4 lens and given t his len's reputation for being radioactive, I took it to my radiology department's radiation safety physicist and she tested it on the department's Geiger counter. No radiation was detected (it detects beta and gamma radiation, not alpha particles). I have seen another video where this lens was shown to be definitely radioactive (that lens had a serial number around 71000). My len's serial number is in the region of 313,000. I wonder if later versions of this lens removed the thorium from the glass manufacture?
I have a Jupiter-9 85mm lens with yellow glass. Rarely used it nowadays because it flares a lot!
Hello.
Are you sure you are not confusng with the color of the lens coating?
What is the serial number of your lens?
The coating of Jupiter-9 lenses started with a chemical coating, evolved to a single layer coating and moved on to a multi coating. The tint of the early coatings in the 50s was light blue, but also light yellow.
I have evidence of serial numbers strating with 58...that have a yellow color for the lens coating.
In the 60s the color of the coating changed to blue/violet.
Flaring is quite common for early Jupiter-9 lenses...anyway, may I suggest you to clean all the lenses (including the internal ones) and use a hood?
@@patriziodalessandro1693 I left it stored inside my room. I'll check it when I'll get home later.
Yes, good advice on the hood. My Jupiter-9 flares dramatically, but a good deep hood, or even my hand, makes a big difference.
Maybe my 2nd Super Tak 55 wasn't radioactive as it wasn't as good as my first, it was just an average lens like most cheap 50mm M42 lenses.
But neither had yellowing anywhere near as strong as my 50mm f1.4, which I cleared mostly, leaving some yellow for the character. It was very yellow. I miss both my first 55, and my 50 when travelling. They can do things others can't.
I will buy a few 55's when back home to try and find that magic filmic look my 1st had- should never have swapped it for one which looked better from the outside. 🙄 The dust and hair and other bits in the glass probably added to the character, so I will buy cheap ones, maybe even with fungus.
I have found an inexpensive way to store my radioactive lenses to limit exposure during storage at home or in my camera bags. Lead roof flashing is fairly inexpensive and available at home improvement stores. The lead is easily cut and very easy to form using a hammer. With very little work one can make a cup-shaped piece of lead shielding conformed to individual lenses. Just set the lens in the cup with the rear lens glass facing the bottom of the lead “cup”.
The issue with most of the measurements is that most of the geiger counters used are not sensible or precise when it comes to alpha.
I mean the decay products gamma, x ray and beta is also high enough to make the geiger counter scream to distingush a radioactive from a non radioactive one, but still the measurements itself are highly unprecise
I like the nikkor N auto 35mm f1.4, is radioactive.
I wonder if the yellowing gets cured off lenses that are not radioactive too.
It may be a completely off the wall thought but maybe the reason why some of the same models were or were not radioactive was the availability of the material. I'm sure you couldn't just go down to the corner store and buy a bag of Thorium whenever you needed it.
But more seriously: Are there any discernible differences in terms of image quality, bokeh, color rendition etc. between the two Super Takumars that are the same model where one is and one is not radioactive? Because if there aren't, then why did they bother putting in the Thorium?
Good question! From what I've read, the thorium not only helped with light control and colour contrast etc (if you took the same piece of glass, one with thorium and one without), but it also made it cheaper to make lenses, as you needed less glass.
Hello Simon - I asked a question in a previous post. Sorry for multiple posts. I bought an 8 element rajkumar thinking it wasn't radioactive. From your post however, it seems like the later versions might be. The serial no on mine is 1572978. Can you tell if this is a later one? Thanks in advance.
Hi, yes that serial number is definitely a later one. I'm afraid I don't know how radioactive your lens might be (if at all) given this serial number. All I can say is that my own later version - 1378881 - is really not very radioactive compared to some other lenses made by Takumar and others.
@@Simonsutak thanks for taking the time to answer! Much appreciated.
i have sekor 55mm 1.8 very yellow backglass, gives a "bokeh" similar to a helios 44-2, also anything about Rexatar lenses? regards!
I’ve recently got that Mamiya/Sekor 55mm f1.8 and it is radioactive. It’s also produces nice results! Don’t know anything about Rexatar lenses.
@@Simonsutak nice thanks for answering! regards!
Your gigercounter doesnt do alpha radiation. Your findings might be off a little. I have a ussr lens that has lanthanum in it and it is not detectable with that giger counter but it is detectable with a pancake alpha probe.
Many thanks for this information about lanthanum. I need to find a professional counter and take my lanthanum lenses for a check-up.
Will do the yellow tint grow back after curing it ?
Yes, I believe it will.
I have that 8 element Super Tak and I've heard it ISN"T radioactive? Now you're telling me it is? It has a scratch (very tiny) on the back glass, does that pose a risk for me to use? Would furthering along that scratch mean putting potentially dangerous radioactive particals in the air? I've heard thats the only way they can ACTUALLY be harmful
I think that the scratch should be fine...it's when a new scratch is made and particles from the glass somehow get through your skin, through a cut , or you swallow them etc.
Do the lenses that are not radioactive, but are yellow, still clear up under UV light?
I also was wondering - did you ever find out?
@@shawnconvey7323 No, actually i just bought a 2x B Canon extender for an old Canon FD 100mm f4 macro mount on the fuji. It also has a quite yellow appearance. I may try leaving it in the sun i guess.
Hii Simon.
I have a Petri 55mm lens. Is this a radioactive lens? If so, does that mean I fucked up? I used it more than 2 years
I've not seen Petri on any of the lists of radioactive lenses. I have several of their lenses (including a couple of 55's), and I've seen no indication of any tells for radiation. Plus, Petri was definitely a budget lens and camera maker, and so I doubt would have wanted to pay the expense of thoriated glass. It seems primarily to have been used in higher quality, or more premium lens lines.
Have you ever seen fungal growth on a radioactive lens? Does the radioactivity prevent fungal growth?
Yes, I've seen fungus inside radioactive lenses. For example, inside an Auto Chinon 55mm f1.4 (more than one lens) - front and rear elements.
Yellow saves a LUT when making a cinematic video
if you deyellow the glass will they stay clear or get yellow again?
They will yellow again, but it will take several years to do so.
Late to the party, but is there a way to ACCELERATE the yellowing of radioactive lenses, and are there adverse effects to doing so? Like, it won't go critical or anything right? like i mean I'm single and all but like haha don't wanna diejustyethaha. Acquired a Canon FL 58/1.2 in super good condition and have been having alot of fun with it, but would love to have more of the vintage golden tint. Without dying of course. Haha.
I don't know how to accelerate the yellowing. But, like vampires, radioactive glass doesn't like light, especially UV light, so I'd keep the lens in the dark/a dark case.
@@Simonsutak Thanks for the reply. Been shoving it right at the edges of the sun for those lovely flares, kinda seem like I'm running on limited ammunition at this point. Hope mine won't lose the tint.
I like the yellowish glass and quite honest I dont care about radioactivity. Just walk through the train station in Stuttgart Germany and your Geiger Mueller Counter will go nuts. Or even some old watches are radio active. I mean, I dont keep my lenses under my pillow at night :)
I wonder who found out that some lenses are radioactive, I suppose the manufacturers didn’t promote their lenses as being radioactive so I think for a long time nobody knew anything about it.
🤔
Good question, I'll have a look through some old lens catalogs and see if it's mentioned at all. I wonder whether they told their assembly line staff they were working with radioactive glass? (There is a view that companies stopped making radioactive glass because of the dangers to the production staff).
How i can check my lens is randioactive ?
We did you get the geiger counter?
I bought it on Amazon.
Flickr does not recognize "Simon's utac" So how doe we get to see your beautiful work?
You had me worried there. It's actually "Simon's utak" and here is the link: www.flickr.com/photos/95859572@N06/
@@Simonsutak Thank you so much!
@@Simonsutak What might be an interesting experiment would be to take some film & enclose it in a light-proof medium & see how close to the lens & how long it takes to fog the film.
I like keeping my canon fd asphericals tinted with yellow, btw do you speak tagalog? Cause I know utak is brain
No I don't speak tagalog, but yes, I did know it means brain. I thought it was a fun phrase! Cameras and lenses are my brain.
Why does UV clear the yellow color?
I don't know the precise science, except to say UV radiation from the sun can kill a variety of things, including the discolouration in radioactive glass.
Great video, do you know if Nikon 50mm 1.8D is radioactive? Or others Nikon serie E lens are radioactive?
What camera u mounting them on..
Two cameras - a Full Frame Pentax K-1 and a Sony crop a6000.
@@Simonsutak thx
I sleep with my Auto Rikenon 55mm f1.4 under my pillow
Editing whoopsie at 10:15
Quite right. That is the original color of the coating of the lens
The Beatles loved them
I buy them all the time the more radioactive the better, don’t even have a camera lol just my radiation detector equipment 😂
I regret curing my Rikenon 55 1.4 :(
Just add the yellow back in processing and enjoy, I love the Rikenon 55 f1.4 use mine all the time at f1/4 for that Bokeh
They are so mildly radioactive that they do not pose any realistic health hazard.
Someday when science comes up with a solution, radioactive lenses will be used to power cameras.
But something important that nobody says: THE RADIOACTIVE ELEMENTS FULFILL THE FUNCTION OF ELIMINATING THE FORMATION OF FUNGUS OR ANY BIOLOGICAL ENTITY THAT IS POSSESSED IN THE INTERNAL LENSES.
If they were dangerous, authorities had already banned them.
This just doesn’t hold true when money is involved. Just look at all the horrible chemicals DuPont make and are allowed to use - specifically C8 and Teflon that are all over things we cook with!
Take home lesson: If it looks like a duck, swims like a duck, and quacks like a duck, then it *MAY or may NOT* be a duck😱🤓🤔
It could be a goose!
@@Simonsutak Heh heeeh.
Indeed a Canadian in that!
Ok.. Little radioactivity & radiation.. Hehehe who would know it, is actually beneficial for humans.. Hehehe now the question is what's little?
all my Chernobyl's are sharp,taks carl,kmz's blah blah..as for cure or leave i cure ..
The Carl Zeiss Pancolar 50mm F/1.8 is uncureable.
I am not going to repeat my negative comments on Camerapedia. Once is enough.
Glass containing lanthanum (and thorium) are sometimes called HEAVY Crown. These types of glass were developed in the 30s (Morey) to increase the refractive index and decrease color dispersion, producing materials which were not available before - regardless of their weight.
99,9% of lanthanum found in nature is NOT radioactive. If Lanthanum was radioactive, then all lenses produced during the last 70 years would be radioactive. One example for all: Leitz always refused to use thorium, but pumped their glass with very high percentages of lanthanum.
Anyway lanthanum must be purified, since it is obtained from Monazite. This mineral contains also iron, cesium and other rare earth elements. Lanthanum with a 0,16% in weight of cesium will have a very strong yellow tint, while iron would add an orange/amber dominant. This is one of the answers to your questions.
While experimenting at the time of Manhattan Project, scientists used optical devices to inspect the reactor and found that glass exposed to radiation turned to a dark brown color and found that when adding rare earth elements (lanthanum, cerium, etc.) to the glass, the color intensity could be reduced. The term "color centers" was suggested in this initial study.
It is so funny that you keep insisting that UV will miracolously make the yellow/brown tint disappear (as many other reported in the past, since they heard it from the grapevine).
But then you show a LED lamp doing the job.
LED lights do not emit in the UV region (unfortunately, otherwise I would have sued IKEA and made a lot of money since I bought one of these lamps many years ago).
No UV, but the lens lost his yellow/brown color: really a miracle or maybe thanks to something else? Can you find the links on the internet by yourself?
In general, if all people discussing this matter had run their search independently without listening to people that were rambling about things that they heard reported from others, they would have found that this problem was anaylized and solved a long time ago by all the optical engineers and glass makers who work with the aerospace industry: just imagine sending a huge telescope or a ton of spy satellites to find out that your billion dollar equipment must be scrapped because of cosmic radiation suntanning all your lenses.
If you fly long distance quite often you might have a problem - think about these things without any protection orbiting our planet above our atmosphere...
Many thanks for your comments. Especially on Lanthanum and the tinting. On Camerapedia, I mentioned in the video that the lists can be quirky; gave some examples of quirks with my lenses; and said the only way to be sure about radioactive levels is to test you own lenses. On the Ikea lamp....it works on my Takumars (so it emits something that works) - but I wrote on the slide that others need to check whether it will work on their lenses.
@@Simonsutak Ok...you do not want to run a simple googe search: it will work with all, as long as you keep the lens wrapped up in aluminum foil, therefore keeping the HEAT inside.
www.steris-ast.com/techtip/radiation-processing-glass-coloration-discoloration/