Web Analytics RiceHigh's Pentax Blog: Lead Glass and Lead-free Glass for Photographic Lenses

Monday, September 16, 2013

Lead Glass and Lead-free Glass for Photographic Lenses

I agree that these are long reads but really interesting:

http://optics.org/indepth/2/7/3

http://rohs.exemptions.oeko.info/fileadmin/user_upload/Stakeholder_comments/Exemption_13_several_industry-stakeholders_27_March_2008.pdf

Via: http://www.dpreview.com/forums/post/52159193

In short, lead-containing glass is still better optically, less temperature sensitive, more stable and actually cheaper to make. The use of lead in some optical appliances is actually exempted by RoHS directive but the adoption of lead-free glass in photographic lenses is yet the trend and the future of the industry.

Btw, I am glad that I still have some of those toxic Pentax glass that are lead-made, including some of the best F, F*, FA* and FA Limited lenses, which are now used on my Canon 5D3 FF, examples here and here! :-D
Time (UTC +0800):
標籤： , , , , , , , ,

Comments (30)

Loading... Logging you in...
Dashboard | Edit profile | Logout
  • Logged in as
0 Vote up Vote down
John's avatar

John · 599 weeks ago

I wait Sony NEX FF for my FA Limited PEntax....:-)
7 replies · active 599 weeks ago
+3 Vote up Vote down
John's avatar

John · 599 weeks ago

Last Niews: "Pentax France" (in Facebook) change name "Ricoh Imaging France".....Bad reaction in facebook...
-1 Vote up Vote down
Zobing's avatar

Zobing · 599 weeks ago

So, where can we find ta reliable list of lead glass lenses?
4 replies · active 599 weeks ago
-1 Vote up Vote down
6BQ5's avatar

6BQ5 · 599 weeks ago

I thought that lead in glass is relatively safe since there is very risk of exposure. Kids probably will not ingest the glass and even if they touch it they are touching the coatings first before actually touching the glass with lead. Disposal may become an issue if someone throws the lens away but even then the lead is still trapped in the glass, between coatings, so would it really leak into water systems? Maybe the safety issue is for employees making the lenses?
0 Vote up Vote down
RicardoRei's avatar

RicardoRei · 599 weeks ago

What's lead compared to thorium! One of the reasons I bought Pentax was the compatibility with old lenses with good quality and low prices (like Super Takumar 50 mm f1,4... till I found that peculiar yellowish color (that desapears when you expose the lens to the sun or UV) was due to the radioactive composition of (at least) one of the glass elements. The thorium or other radioactive compounds usage is the base of production of low dispersion glass elements. That explains the suspicious good IQ delivered by those old lenses. I've got a FA* 80-200, and I already knew that it doesn't complies with Rohs requirements, I'm happy and I don't give a sh*t, it's safe, period. But I think that i'll never putt my eyes near to one of these: http://www.orau.org/PTP/collection/consumer%20pro... http://camerapedia.wikia.com/wiki/Radioactive_len... http://www.youtube.com/watch?v=T0h-7iAstlA
Regards
1 reply · active 599 weeks ago
0 Vote up Vote down
Mike Kawasaki's avatar

Mike Kawasaki · 599 weeks ago

I wonder what kind of modern glass composition will be used in the manufacture of the new Pentax DA HD 18-70/2.8 lens? Any clue, Rice?
6 replies · active 599 weeks ago
+1 Vote up Vote down
Uncle Vova's avatar

Uncle Vova · 599 weeks ago

It is very interesting information, but...
Yes, we may agree that the old lead-containing lenses, that had been produced many years ago, is optically better then the modern lead-free lenses. So what? Should we start to seek for those old lenses immediately and use them instead of the modern lenses?
By the way, some of the aged people say that generally an old times were better in many aspects then the modern time, and they remember:
in the old days the water was even wetter then today. ;)
So what? ;) Should we seek for the well-spring of old extremely wet water to quench our thirst? ;)
4 replies · active 599 weeks ago
0 Vote up Vote down
RJR's avatar

RJR · 462 weeks ago

Very very nice indeed...Congrats Rice!
Waiting for your impressions...I have the K7 and to me is taking the K1 or leaving Pentax system and sell the FA's * 85, 80-200 and the FA 31 limited...let's see the reviews

Post a new comment

Comments by

Subscribe to: Post Comments (Atom)