> Date: Tue, 06 Mar 2001 23:32:47 -0500
> From: "M.J.Shupe" <[EMAIL PROTECTED]>
> Subject: Re: FD vs EOS
>
> If it were true that nearly all old canon lenses had SSC
> coatings, then why would they specifically market a group
> of them marked that.
FL lenses were mostly uncoated, right. Then canon started
single and double coating, brand named "S.C." and in almost
all FD breech lock lenses went on to "S.S.C.", Super Spectra
Coating. This was not marked SSC to differentiate from
other Canon lenses, it was branded to differentiate against
competitors.
> I imagine that the technology did make it into the mainstream
> of canon lenses,
It did. Canon dropped branding lenses SSC when they introduced
new FD. All new FD lenses have without any exception Canons
own multi coating.
> but this is certainly not the case for early FD lenses or FL
> lenses.
Must be very early FD lenses then. We are talking about
lenses some 30 years old or older......
> I don't know when canon came up with SSC lense,
Very early seventies.
> but prior (I think they had some marked SC as well?)
Single coating, yes.
> but their prior coatings were not good.
FL simply wasn't coated at all, or single coating at best.
> I had an old FD50/1.8 (1981-83 vintage that was purchased
> with an AE-1) that exhibited *terrible* flare performance,
This lens was certainly new FD, and it was certainly SSC
multi coated. Your flare problems might result from lesser
experience, the use of UV filters, the lack of a lens shade,
maybe dirt between the lenses and more factors. But certainly
the coating was not the problem cause.
> If a simple 50mm is poor performing in terms of flare,
Which might have other reasons but design as well, see above.
> then more complex designs most likely will not do well
> at all with these early coatings.
The coatings are pretty much the same today. And 81 to 84
was ten years after coatings were generally available.
Some of the best glass ever was produced in those days.
> This was at the time when SSC lenses were marketed specially,
Certainly not. When I bought my A-1 in February 1981, there
was nothing but new FD available, with SSC coatings having
gathered fame for almost ten years by then. Only two or
three lenses in breech lock design were still available at
that time, mostly special order lenses like the 5.6/1200
or the big 600 mm.
> so I am sure it did not incorporate that technology, and
> this lens had a lower end coating on it.
Certainly not.
> Pentax invented multi-coating (although "invented" can
> have different meanings depending on who, or who's marketing
> department, you are talking to)
Multicoating was invented by Zeiss, as far as I know.
The implementation of mass production coatings for SLR
lenses was maybe done by somebody different.
> and is very well known for having been highly successful
> with them very early on (as in mid seventies, before the
> K-mount came out in 1977). This is the "coating-gap" I
> was referring to.
>From 1973 on the latest, there was no more gap.
> I don't claim expertise on FD equipment at all, except in the
> case of this simple 50mm comparison.
Having owned and professionally operated numerous FD lenses,
I do.
> And I certainly don't have much knowledge of later designs.
You can look that up in canons camera museum.
> I also saw a remark within the last week or so that canon's
> current coatings are not up to the level of current pentax
> or nikon ones, but are very close.
That's rubbish.
> I am quite certain that the current coatings are much
> better than those used on consumer lenses like that old
> 50/1.8, though.
The process is simple and is very well mastered for nearly
30 years now. No, todays coatings are almost the same as
they were 30 years ago. The difference is that today a
production lot will render a higher percentage of quality
passing material.
> > With their own coating process being very succesful,
> > why should they?
>
> I am sure that this is what canon would say.
This is also what all the early 80ies lab tests say.
And it is what shows in results from that time.
> I am not entirely sure what you are saying is "not very
> much different".
See above. I have just checked with a friend who is lens
designer for Rodenstock, and he acknowledged that coatings
are pretty much the same over the last 20 to 30 years.
> My hope is that you are referring to the difference between
> manufacturer's coatings these days.
That as well.
> But if you are referring to the difference between canons
> older coatings and the ones used to day as not being much
> different, then you are mistaken.
Nope. Again see above, there might be more factors involved.
> The current coatings beat the very poor ones on that old
> 50/1.8 by a huge margin.
Dead wrong. At least as far as my experiene as a professional
photographer and the experience of a Rodenstock lens designer
is concerned.
> In any case, I still believe that in any question asking
> the difference between old lens image quality and new lens
> image quality, it would be poor to neglect two of the areas
> of largest change between new and old lenses, specifically
> the coatings and aspherics.
Coatings are no factor as explained above, and a lot of
modern designs are tributing environmental requirements and
production rentability. Look at all the cheap zoom lenses
mark II and mark III. They changed to leadfree glass and
removed distance scale, replaced metal mount with plastic
mount, reduced weight and size in exchange for ruggedness
and optical quality.
Vice versa, a lot of new FD lenses were better than what
you can buy today.
> Plastics certainly are more common these days than in the
> old FD series, but I doubt this has as much impact on the
> image quality as coatings and aspherics.
It has impact on mechanical tolerance in making, but it
reduces temperature induced mechanical variations.
> Probably ED elements are another variable. Canon used
> flourite in many of the old SSC lenses, but not in most
> others.
For several reasons. Fluorite rots easier than other sorts
of glass, it is very expensive in making, grinding and polishing.
> These kinds of elements, as well as more recently developed
> glasses, seem to be much more common today
Todays glasses in some ranges are poor replacements of sorts
that can due to environmental requirements or resource
shortages not be made anymore.
> (just look at any sigma, tokina or probably even pheonix lens
> ad, and you will see ED and aspheric peppered through it).
Yes, and a Leitz or Zeiss lens "Apo" label means something
very different.
> There was, however, the loss of those leaded glasses
> that Michael talked about.
Not just glass, also arsenic and other highly poisonous
ingredients.
> It is my feeling that todays lenses are, on the whole,
> much better.
The technical reality is different. There are some
extraordinary lenses, and mechanical precision has improved
a lot, but there have been cuttings in standards as well.
> However, I am sure there are stars of the old FD line
> that have been lost.
Yes.
> Canon should resurrect, and improve, these old designs.
> I, for one, would like to se an new 35/2.8 TSE.
Being burdened with the D30 factor of 1.6, the 24 mm TS/E
does pretty well.....
> What other jewels are there in the FD lineage that have
> been lost?
The FD new 4.0/70-210 zoom.
--
Michael Quack <[EMAIL PROTECTED]>
http://www.photoquack.de
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