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12-03-2012, 01:10 PM   #16
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The FA 31mm Limited is not a small lens.

12-03-2012, 02:15 PM   #17
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QuoteOriginally posted by TenZ.NL Quote
thanks for the explanation. But then it would be technically possible to design a faster aperture for the given sizes and shapes?
I assume it would, but photographic lens design isn't my particular area of expertize. Look at the Fa limiteds, they are quite small, faster than the DA, have reportedly better central sharpness but lower corner sharpness.

The 35 macro is not as fast as the 35 f2,4 but it's a macro, so other optimizations were done. And you expect a macro to be as sharp wide open as it is stopped down, while you don't expect the same thing of a regular prime.
12-03-2012, 02:26 PM   #18
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QuoteOriginally posted by audiobomber Quote
The FA 31mm Limited is not a small lens.
It fits in between the 77 and D FA 100 WR size wise. The fact that it is a full frame wide angle lens and f1.8 is why it is the largest of the FA LTD.
12-03-2012, 02:28 PM   #19
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The same FA ltds vs the DA ltds are about twice as long and twice as heavy (DA 40 vs FA 43, DA 70 vs FA 77).

On the other hand, the FAs were designed for FF as well.

12-03-2012, 06:51 PM   #20
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QuoteOriginally posted by JinDesu Quote
The same FA ltds vs the DA ltds are about twice as long and twice as heavy (DA 40 vs FA 43, DA 70 vs FA 77).

On the other hand, the FAs were designed for FF as well.
Those aren't really the same lenses. The DA 40 is an optically redesigned version of the old M 40/2.8 pancake. Some of the elements were reworked and Ghostless Coating added. That said, the 43 is still close to pancake size. The 77 is also an f1.8 lens and the 70 is f2.4. Granted the DA 70 is a pancake, but the FA 77 isn't exactly a large lens compared to the 85mm genre.
12-03-2012, 07:16 PM   #21
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This is all very interesting, but where did the OP go?
12-03-2012, 07:19 PM   #22
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Another reason might be that the limiteds are known for the high quality all metal precision built. As you go into the high focal rangers the optics get larger and the lens gets heavier. It might be more difficult to maintain that same consistent quality and have fast/reliable autofocus.
12-03-2012, 08:40 PM   #23
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I have an M135/3.5. It's sharp as a tack, small and light, takes a 49mm filter and has a built in sliding out hood. Imagine this same lens with auto focus and modern coatings.

12-03-2012, 09:24 PM   #24
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I'm enjoying the discussion, calsan.

Being the neophyte I am, I have been researching lenses in the 85 - 150 range from the A and M series, and noted they were all fairly compact. It seems any of these could be refreshed and make for a nice Limited mid-telephoto prime.
12-04-2012, 06:07 AM   #25
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QuoteOriginally posted by jcdoss Quote
Being the neophyte I am, I have been researching lenses in the 85 - 150 range from the A and M series, and noted they were all fairly compact. It seems any of these could be refreshed and make for a nice Limited mid-telephoto prime.
True. In particular, the M120 and M150 are absurdly small for their reach. And great lenses too! I've owned and used both for a while.
12-04-2012, 07:44 AM   #26
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QuoteOriginally posted by reeftool Quote
I have an M135/3.5. It's sharp as a tack, small and light, takes a 49mm filter and has a built in sliding out hood. Imagine this same lens with auto focus and modern coatings.
+1
I'd love a limited version of my M135 3.5. It would be the logical contiuation of the series: 15mm, 21mm, 40mm/35mm, 70mm, 135mm
12-04-2012, 08:37 AM   #27
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QuoteOriginally posted by beeldmark Quote
+1
I'd love a limited version of my M135 3.5. It would be the logical contiuation of the series: 15mm, 21mm, 40mm/35mm, 70mm, 135mm
Yes, and it would be doable for them to make as they have made the basic lens before. It is my one manual focus lens that I have no reservations about using. I used it at my daughters college graduation. With the smaller image circle of aps-c, they might even even be able to make it a bit faster than f3.5 and still keep the 49mm filter size. The problem is that 135mm isn't a popular size any more and there would likely be more grumbling and complainers about it than buyers.
12-04-2012, 01:07 PM   #28
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I think 135mm is kind of a funky FL on APS-C. It's a little long for medium-long distance portraits and not really long enough for long shots. That, and some pretty strong PF on bright sunny days are why I sold my F 135/2.8.

If I really want to use wide apertures at the 135mm FL I've got my cheap old Albinar 135/2.8 that's actually pretty good for the $15 I spent on it. Otherwise my F 70-210 is much more versatile and quite nice optically.

Since 100mm is already covered by the DFA 100/2.8 macro, I think a modern Limited version of the M 120/2.8 would be pretty sweet.
12-05-2012, 05:58 AM   #29
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QuoteOriginally posted by reeftool Quote
With the smaller image circle of aps-c, they might even even be able to make it a bit faster than f3.5 and still keep the 49mm filter size. The problem is that 135mm isn't a popular size any more and there would likely be more grumbling and complainers about it than buyers.
QuoteOriginally posted by msatlas Quote
I think 135mm is kind of a funky FL on APS-C.
Pentax also have a 150mm f3,5 design in their legacy drawer... really compact lens. The 120 is even smaller.
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