List of lens diagrams: triplets, planars & hybrid lenses

aoleg · Joined: 22 Feb 2008 Posts: 1387 Location: Berlin, DE

BTW, I found this link http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=001EOj reviewing many books on lens design. I read a few, and think this collection (and ratings) are adequate.

no-X · Posted: Sat Mar 06, 2010 10:17 am Post subject:

Guliver: That is interesting. Prakticar 28/2.8 was always described as B-mount version of the Pentacon 29/2.8. But it can be wrong. E.g. prakticar 50/2.4 is often described as 5/4 lens, but mine seems to be 4/4 Confused

Could you identify, which lens element is "missing", or is the optical scheme completely different?

Guliver · Joined: 05 Mar 2010 Posts: 9

Ok, here is a very rough diagram of what I've got. Again, I have to mention, that my lens is M42x1 screw mount. Lens name (as written on body): Prakticar 2.8/28 PM Pentacon MC

Updated on 9.03.2010

Again, it is very rough sketch. First two lenses on the left side (right before the aperture) are the most uncertain.

no-X · Posted: Tue Mar 09, 2010 8:55 am Post subject:

That's quite atypical lens. I have never seen it. The lens diagram is also a bit uncommon - retrofocal lenses often have negative front elements. It could mean, that the lens is quite late optical design based on modern types of glass.

Does it state something like "made in ..."?

Guliver · Joined: 05 Mar 2010 Posts: 9

Oh, sorry! I drew it wrong - the front lens looks a little bit different. I've just replaced the existing diagram with more-or-less right one.
No, it does not state anything about manufacturer. It has serial number though...don't know if it is possible to check manufacturer through that information.

BRunner · Joined: 29 Jul 2009 Posts: 705 Location: Czech Republic

Yesterday I cleaned my Elmarit 135. I didn't found optical diagram, so here is rough sketch. It's a Ernostar/Sonnar hybrid?

taunusreiter · Joined: 20 Mar 2007 Posts: 127

Yes it is. And quite similar to the Zeiss 135/2.8

Latente · Joined: 12 Jan 2010 Posts: 18

yesterday i open a broken ricoh 500g. I ever think that was a 4/4 tessar,
but when i open it the lens was a 4/2 and the lens scheme look like this:

i don't open the front and the rear group so i can't say if the group are cemented or not.

what do you think? still a tessar? or a dialyte?

calvin83 · Joined: 12 Apr 2009 Posts: 7588 Location: Hong Kong

Latente · Joined: 12 Jan 2010 Posts: 18

nixland · Expire: 2012-07-29

I just found some Leica lens diagram from this website :

http://www.rglewis.co.uk/LEICA/R/R_Lenses/R_Lens_Range.htm

From the 3 diagram that compiled by no-x on page #1 :

Summilux 80/1.4 = planar?

Summicron 90/2 looks like 5 element Takumar?

Summilux 50/1.4 = ultron?

Summicron 50/2 = planar Biotar?

CMIIW

kelsonbueno · Joined: 29 Apr 2011 Posts: 7

Hi! I´m looking for the lens diagram of Vivitar automatic tele converter 2x-8.
I´m looking allover internet but with no success.
Maybe other 2x teleconverter use the same diagram.. if someone have other, please, could you post?
thank you!

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

Do you have the model number or name of the Vivitar 2x8 TC? Me, I've never heard of a Vivitar 8-element 2x TC. Seven, yes, but not eight.

kelsonbueno · Joined: 29 Apr 2011 Posts: 7

It´s a M42 teleconverter. Just have this entries on the lens.
There is: http://www.flickr.com/photos/8991613@N04/sets/72157626484913729/

I bought it cheap.
The lens has some fungus, and during cleaning i got confuse and lost the order and position of each element.

Thank you.

kelsonbueno · Joined: 29 Apr 2011 Posts: 7

anyone?

koji · Expire: 2012-12-27

koji · Expire: 2012-12-27

I was also very curious, so I disassembled my Prakticar 28/2.8 (plastic version).
(I have three Prakticar 28/2.8s, the other two are metallic construction.)

Optical block diagram looks like in RED.
(black one is Orestgor 29/2.8 )

The first element has very strong negative, aperture is between 3-rd and
4-th element, I am not quite sure about 2-nd and 3-rd element but they
form very strong positive power. Yes, the lens has 7 element and 7 group.

in short:

The second and third elements are much closer than this diagram indicates, I think.

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

Guys, I've made the offer before, but I figure I should again since it's been so long ago. I have the Cooper books for both Nikon and Minolta system and the Canon F-1 book. Each of these books shows lens diagrams for all of the current lenses as of the date of their publication. In the case of the Nikon and Minolta books, these dates are probably sometime in the early 1970s (non AI Nikkors for example, and no MD Rokkors -- just MC), but the Canon books I have go to 1977 I believe, so they include all of the breechlock FD lenses.

So if you are interested in any of the lens formulas that were current during these time frames, let me know. I can scan them and post them here for your perusal.

kelsonbueno · Joined: 29 Apr 2011 Posts: 7

cooltouch
Is there any 4 element teleconverter on this book?
Thank you.

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

Good question. I looked for teleconverters in both Joseph Cooper publications (Nikon and Minolta) and in the Canon F-1 Guide. In one of the Nikon books, Cooper discussed teleconverters at some length, and mentioned that Nikon did not make any. This was back in 1974, so pre-AI days. Coopers books on Minolta were copyrighted 1972, 73, and 76, and showed only MC lenses, and his book showed no teleconverters either. The Canon F-1 guide showed a 2x converter along with a few of its fluorite telephotos, and while the book showed the optical formulas for the teles, it did not for the 2x. Oh well. I tried.

kelsonbueno · Joined: 29 Apr 2011 Posts: 7

cooltouch
thank you for the search!
I think that teleconverters are not much "well seen" from the manufacturers, just in case that it could be sold and make money.

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

Interestingly enough, I did a google search on the topic, looking at the "images" and found quite a few optical formulas for 7-element TCs, but none for 4-element TCs.

kelsonbueno · Joined: 29 Apr 2011 Posts: 7

cooltouch
I did the same, but with no success.
The modern canon 1.4x TC use 4 element, but I didn´t saw any diagram, just some specs.
I´d found some 5 elements TC but in this case reference isn´t enough.
The vivitar series 1 also have one 4 element TC, but there´s no more info about it.

calvin83 · Joined: 12 Apr 2009 Posts: 7588 Location: Hong Kong

kelsonbueno · Joined: 29 Apr 2011 Posts: 7

My mistake!
I found this nice info about tele converters!
http://www.pierretoscani.com/echo_focal_length.html#FocalLength07