| View previous topic :: View next topic |
| Author |
Message |
Tonythetigger
Joined: 29 Nov 2020
Posts: 2
|
 Posted: Sun Nov 29, 2020 6:48 pm Post subject: SMC Takumar Macro 100mm f4 radioactive? |
 |
|
Tonythetigger wrote:
I haven't been able to find out any information about this particular lens and I'm thinking about buying it. Does anyone own it and is able to measure it with a geiger? |
|
| Back to top |
|
 |
D1N0
Joined: 07 Aug 2012
Posts: 2491
|
| Posted: Sun Nov 29, 2020 8:09 pm Post subject: |
|
|
D1N0 wrote:
Not likely. Not necessary in a simple f4 lens.
_________________
pentaxian |
|
| Back to top |
|
|
CarbonR
Joined: 31 Dec 2008
Posts: 1969
Location: Clermont-Ferrand, France
|
| Posted: Sun Nov 29, 2020 8:12 pm Post subject: |
|
|
CarbonR wrote:
Do you know that even you are radioactive (yes, because your body is for example full of carbon) ? If you do not stare open eye 24/24h on the lens, you will receive more radioactivity from the air than from the lens. BTW, 100/4 is not know as using tyhorium or other radioactive lenses.
_________________
Cameras : Canon 5D, Pentax K100D, Pentax 6x7, Spotmatic
Lenses : 15mm to 1000mm (24x36)
My websites : [FR & ENG]Takumar - the eyes of the Spotmatic : info about all Takumar lenses // Kogaku - My photo site
I am selling : Takumar lenses and rare Pentax bodies, pm me if you're interested in something [MFLenses feed-back]
Information on Takumar lenses with samples :
Wide angle : Takumar 15/3.5 15mm, Takumar 17/4 17mm, Takumar 18/11 18mm, Takumar 20/4.5 20mm, Takumar 24/3.5 24mm, Takumar 28/3.5 V1 28mm, Takumar 28/3.5 V2 28mm, Takumar 35/2 V1 35mm, Takumar 35/2 V2 35mm, Takumar 35/2.3 35mm, Takumar 35/3.5 35mm, Takumar 35/4 35mm
Standard : Takumar 50/1.4 V1 50mm, Takumar 50/1.4 V2 50mm, Takumar 50/3.5 50mm, Takumar 50/4 50mm, Takumar 55/2 55/1.8 55mm, Takumar 55/2.2 V1 55mm, Takumar 55/2.2 V2 55mm, Takumar 58/2 58mm, Takumar 58/2.4 58mm
Short tele : Takumar 83/1.9 83mm, Takumar 85/1.8 85/1.9 85mm, Takumar 85/1.8 85mm, Takumar 100/2 100mm, Takumar 100/3.5 100mm, Takumar 100/4 100mm, Takumar 105/2.8 V1 105mm, Takumar 105/2.8 V2 105mm, Takumar 120/2.8 120mm
Telephoto : Takumar 135/2.5 V1 135mm, Takumar 135/2.5 V2 135mm, Takumar 135/3.5 V1 135mm, Takumar 135/3.5 V2 135mm, Takumar 150/4 V1 150mm, Takumar 150/4 V2 150mm
Long tele : Takumar 200/3.5 200mm, Takumar 200/4 200mm, Takumar 200/5.6 200mm, Takumar 300/4 V1 300mm, Takumar 300/4 V2 300mm, Takumar 300/4 V3 300mm, Takumar 300/6.3 300mm, Takumar 400/5.6 400mm, Takumar 500/4.5 500mm, Takumar 500/5 500mm, Takumar 1000/8 V1 1000mm, Takumar 1000/8 V2 1000mm
Zoom : Zoom-Takumar 45~125/4 , Zoom-Takumar 70~150/4.5 , Zoom-Takumar 85~210/4.5 , Zoom-Takumar 135~600/6.7
Achromatic : Ultra-Achromatic-Takumar 85/4.5 , Ultra-Achromatic-Takumar 300/5.6 300mm |
|
| Back to top |
|
|
y
Joined: 11 Aug 2013
Posts: 304
Location: EU
|
| Posted: Sun Nov 29, 2020 8:25 pm Post subject: |
|
|
y wrote:
I've verified my S-M-C Macro Takumar 50/4 and the result was positive. However, the dose is truly miniscule compared to, for instance, S-M-C Takumar 50/1.4 or Zeiss Jena Pancolar 50/1.8.
No experience with the 100/4, but one would expect it to be more or less the same as the 50/4. |
|
| Back to top |
|
|
visualopsins
Joined: 05 Mar 2009
Posts: 10532
Location: California
Expire: 2025-04-11
|
| Posted: Sun Nov 29, 2020 9:05 pm Post subject: |
|
|
visualopsins wrote:
They're Grrrrrrrrrrrrrreat!
Welcome Tonythetigger
50mm Macro-Takumars have 4/3 optics while 100mm Macro-Takumars have 5/3 optics. The 100mm is not on any list, even in the community-maintained database at https://camerapedia.fandom.com/wiki/Radioactive_lenses
Somebody guesses the reason for less radiation from 4/50mm Macro-Takumars than for 1.4/50mm Takumars (except 8-element) is use of lanthanum in glass formula. 1.4/50mm lenses used both lanthanum and thorium.
_________________
☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony ILCE-7RM2, Spotmatics II, F, and ESII, Nikon P4
Lenses:
M42 Asahi Optical Co., Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200, Tele-Takumar 1:5.6/200, 1:6.3/300, Macro-Takumar 1:4/50, Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm, Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element), Super-Multi-Coated Fisheye-TAKUMAR 1:4/17, Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500, Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100, Super-Multi-Coated Bellows-TAKUMAR 1:4/100, SMC TAKUMAR 1:1.4/50, 1:1.8/55
M42 Carl Zeiss Jena Flektogon 2.4/35
Contax Carl Zeiss Vario-Sonnar T* 28-70mm F3.5-4.5
Pentax K-mount SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto (Kiron)
|
|
| Back to top |
|
|
Tonythetigger
Joined: 29 Nov 2020
Posts: 2
|
| Posted: Mon Nov 30, 2020 5:29 am Post subject: |
|
|
Tonythetigger wrote:
Thank you! |
|
| Back to top |
|
|
stevemark
Joined: 29 Apr 2011
Posts: 3754
Location: Switzerland
|
| Posted: Mon Nov 30, 2020 11:28 pm Post subject: |
|
|
stevemark wrote:
| visualopsins wrote: |
Somebody guesses the reason for less radiation from 4/50mm Macro-Takumars than for 1.4/50mm Takumars (except 8-element) is use of lanthanum in glass formula. 1.4/50mm lenses used both lanthanum and thorium. |
Probably it's simply the difference in size. Rough estimation:
Lens diameter in a 1.4/50mm => about 35mm
Lens diameter in a 4/50mm => about 12mm
The lens volume - assuming a similar shape - would be about 25 times larger in a 1.4/50mm lens, compared to a 4/50mm lens.
Well, this is a really nothing but a rough estimation, but it explains why the 4/50mm has so much less radioactivity compared to the 1.4/50mm.
S
_________________
www.artaphot.ch |
|
| Back to top |
|
|
visualopsins
Joined: 05 Mar 2009
Posts: 10532
Location: California
Expire: 2025-04-11
|
| Posted: Mon Nov 30, 2020 11:59 pm Post subject: |
|
|
visualopsins wrote:
| stevemark wrote: |
| visualopsins wrote: |
Somebody guesses the reason for less radiation from 4/50mm Macro-Takumars than for 1.4/50mm Takumars (except 8-element) is use of lanthanum in glass formula. 1.4/50mm lenses used both lanthanum and thorium. |
Probably it's simply the difference in size. Rough estimation:
Lens diameter in a 1.4/50mm => about 35mm
Lens diameter in a 4/50mm => about 12mm
The lens volume - assuming a similar shape - would be about 25 times larger in a 1.4/50mm lens, compared to a 4/50mm lens.
Well, this is a really nothing but a rough estimation, but it explains why the 4/50mm has so much less radioactivity compared to the 1.4/50mm.
S |
_________________
☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony ILCE-7RM2, Spotmatics II, F, and ESII, Nikon P4
Lenses:
M42 Asahi Optical Co., Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200, Tele-Takumar 1:5.6/200, 1:6.3/300, Macro-Takumar 1:4/50, Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm, Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element), Super-Multi-Coated Fisheye-TAKUMAR 1:4/17, Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500, Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100, Super-Multi-Coated Bellows-TAKUMAR 1:4/100, SMC TAKUMAR 1:1.4/50, 1:1.8/55
M42 Carl Zeiss Jena Flektogon 2.4/35
Contax Carl Zeiss Vario-Sonnar T* 28-70mm F3.5-4.5
Pentax K-mount SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto (Kiron)
|
|
| Back to top |
|
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
Search
Memberlist
Register
Profile
Log in to check your private messages
Log in
