Dumb question, but are they exactly the same coating formula, or was there a bit of tweaking when Asahi went from "Super-Multi-Coated" badge to "SMC Pentax" badge on their lenses?
And has there been any problems reported with the older Super-Multi-Coated coating wearing off on the bigger lenses (M42 mount)?
Coatings were constantly being worked on, from lens to lens, and even in the same series of lenses, so I doubt they are identical. The thing is, though, they are terrific either way.
Coatings can be rubbed off any lens with the right (wrong) kind of abuse, so I would say that it is certainly possible for them to be worn off a S-M-C-Tak or SMC Pentax.
I was not aware of any coating differences, but I don't know that there were not. Is there a definitive source about coating differences P? The main difference as far as I am aware between SMC and Super Multi Coated badged lenses is the build and style with the SMC's looking cheaper with a rubberized focus ring and the Super Mulit Coated lenses being all metal.
Tariq Gibran wrote:
Is there a definitive source about coating differences P?
No, just an article I read a long time ago, about how Fuji basically invented multi-coating and then Asahi-Pentax (and Zeiss) jumped on the bandwagon and stole Fuji's thunder, and on about how variations of coatings were implemented throughout the lifetime of the products, in much the same way that Oly did with theirs.
cogitech wrote:
....No, just an article I read a long time ago, about how Fuji basically invented multi-coating and then Asahi-Pentax (and Zeiss) jumped on the bandwagon and stole Fuji's thunder....
From: http://www.company7.com/zeiss/history.html
"Another noteworthy milestone was on November 1, 1935 when Alexander Smakula a staff member at Zeiss developed and then patented anti- reflective (T Transparenz) coatings"
From: http://photo.net/medium-format-photography-forum/00GrBN
T* coatings were introduced in the fall 1972 with no fanfare. It was Zeiss's multicoating process. In 1974 Zeiss started marketing "T*" as a reaction Pentax's SMC (Super Multi Coated) lens ads...........
........Yeah, it all goes down to Pentax's decision to come out and declare their multicoating as a big deal. I was talking to our local Leica rep (who is German from Wetzlar and has worked there 30 years) that Leitz was using multicoating on certain lenses since the 40s, but it never occurred to them to tell anyway. He chalked it up to the general tendency of the Japanese companies to be much better at marketing innovation, while the older German mentality was to let the products speak for themselves......
"When Asahi Opt. Co. introduced their Super-Multi-Coated Takumar lenses in 1971, there were many different reactions to this announcement. According to an article authored by Fabio Amodeo and published in September of 1972 by Photo 13 magazine, Nikon stated that they already employed multi-layer coatings (up to three or four) on some lens surfaces and Asahi was fooling photographers, since no more than 5 layers were technically possible. Also Canon and Leitz said they were developing a similar process, but 7 layers was far from being credible. To the contrary, Fuji said they were ahead, since they already had developed their own EBC (electron-beam coating) technology up to 11 layers, employed on some lenses for movie cameras on occasion of 1964 Olympic Games. Further in reaction of the Asahi announcement, Fuji said they were going to use EBC on camera lenses very soon."
cogitech wrote:
Coatings can be rubbed off any lens with the right (wrong) kind of abuse, so I would say that it is certainly possible for them to be worn off a S-M-C-Tak or SMC Pentax.
Actually the reason I asked about any reported SMC Tak coating problems is this sentence in cameraquest's description of Kilfitt lenses, and was wondering if it applies to other manufacturers; specifically the S-M-C-Tak 500mm I am looking at.
"Kilfitt's and Zoomars are fine lenses of great precision and optical performance.... The 300 and longer non-mirror lenses are more likely to have coating problems than not, leading me to believe the factory coating on large lens surfaces was often not up to the challenge." Source: http://www.cameraquest.com/kilzoom.htm
I think they are talking about internal element coatings or else they wouldn't have singled out only the larger lenses. Now if KEH ever ships my Kilfitt 600/5.6 I can see if that coating wearing off statement is correct or not.
My understanding from all that I have previously read was that Zeiss invented single coatings as mentioned above. When originally used in the fifties up until mid-late 70's(when T* multi coating finally shows up), the red T(no *) on a Zeiss lens meant a single coating. Pentax later invented Multi Coating which was a breakthrough and was licensed by Zeiss ane everyone else(this is the lore, perhaps its wrong?). Fuji never used multi coating until their EBC (electron beam coating) coating process was introduced very late in the game, late 70's or so.
I guess it comes down to what these different companies said and when multi coating actually shows up on their mass produced lenses. It seems to me that multi coating first shows up on readily available Pentax lenses. Many Nikon lenses were not multi coated until after Pentax started using multi coating. I don't recall seeing any EBC fuji lenses in the G690 series or their large format lenses until the late 70's or so (perhaps their 35mm lenses were different?). Zeiss also did not use T* multi coating on their Hasselblad Zeiss lenses until after the mid 70's. Thats just what I have noticed from buying and using all these brands over the years. Perhaps these companies had the technology but they simply did not implement it in a big way before Pentax. Why?
Pentax did not invent multi-coating. They did popularize it and were the first to use a large number of layers on 35mm lenses. Fuji's EBC was not used on 35mm lenses until after SMC showed up.
T* coating is generally assumed to originally have been licensed SMC coating. Pentax got the design for the SMC Takumar 15/3.5 in return.
S-M-C vs SMC comes down to how old the lenses are. The coatings were continually evolving but the differences are not huge. The biggest difference between the two are the new barrels that most of the SMC lenses got at the same time.
mawz wrote:
Pentax did not invent multi-coating. They did popularize it and were the first to use a large number of layers on 35mm lenses. Fuji's EBC was not used on 35mm lenses until after SMC showed up.
T* coating is generally assumed to originally have been licensed SMC coating. Pentax got the design for the SMC Takumar 15/3.5 in return.
S-M-C vs SMC comes down to how old the lenses are. The coatings were continually evolving but the differences are not huge. The biggest difference between the two are the new barrels that most of the SMC lenses got at the same time.
So, if you are saying that Zeiss licensed Pentax SMC coating, then who invented Multi Coating if not Pentax?
Tariq Gibran wrote:
So, if you are saying that Zeiss licensed Pentax SMC coating, then who invented Multi Coating if not Pentax?
Pentax patented a particular method of achieving up to 9 layers of coatings, this is what Pentax licensed to Zeiss in return for the optical design(s) of the 15/3.5. Fuji's EBC coating for example could go to 11 layers using a different method, nobody else at the time was using more than 4 layers.
Your info on Katherine Burr Blodgett is pretty amazing and interesting. Thanks. She apparently started the whole field of optical coatings according to this: http://chem.ch.huji.ac.il/history/blodgett.html
BUT, she did not come up with the hard, multilayer optical coatings such as is used in multi coated optics. From the same article:
"The one aspect of Dr. Blodgett's work on nonreflecting glass requiring further research was the development of harder coatings which could not be wiped off."
So, sounds like she got the ball rolling but someone else invented the hard, multi layer coatings.
Ok, so if Zeiss licensed Pentax SMC coating, does it mean that Pentax SMC lenses should show the same micro-contrasts that the Zeiss lenses show? Do they?
Btw, digging more on Dr. Blodgett's work on wikipedia... she was quite a remarkable scientist.
Silentlight wrote:
Ok, so if Zeiss licensed Pentax SMC coating, does it mean that Pentax SMC lenses should show the same micro-contrasts that the Zeiss lenses show? Do they?
Btw, digging more on Dr. Blodgett's work on wikipedia... she was quite a remarkable scientist.
I do remember though that Pentax did make a big deal about their "Super Multi-Coated" Takumars when they first put it on the market. In 1974/75, I was given my first new camera, it was a Pentax Spotmatic II with a SMC Tak 50 (1.8?) and that coating was supposed to be the best available.
Silentlight wrote:
Ok, so if Zeiss licensed Pentax SMC coating, does it mean that Pentax SMC lenses should show the same micro-contrasts that the Zeiss lenses show? Do they?
Btw, digging more on Dr. Blodgett's work on wikipedia... she was quite a remarkable scientist.
Apart from the 15/3.5 (being a Zeiss design, although the two Pentax versions of this lens are not identical to the C/Y version), no.
However flare resistance should be similar between similar optical designs from Zeiss and Pentax. There's a lot more to the Zeiss performance than just the coating technology, and it's almost assured that while the same coating technology was used, the actual coatings differ as Zeiss would chose coatings to their spec, not Pentax's even if using Pentax's coating technology.
Coatings date way back, even earlier than what has been discussed here I think. there was a big article about it in Pop Photo 1974 (I forget what issue) that I just read yesterday. Basically several companies and the military were using it from fairly early on, including Leica, but not everyone was talking about it. That started with the japanese companies using it for marketing.
Indeed it got carried away in the 70s. The gist of the article was that internal lens baffling and using a hood helped a lot more than even the best coatings. And some coatings got up to 17+ layers, since some layers were binders, and sometimes layers interfered with each other so there would be an intermediate layer to get them to play nice, etc. That is why sometimes the # of layers got exaggerated.
I can find out the exact issue date/page/etc, if someone really wants to read it. It was fairly in-depth technically, which was nice.
