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05-02-2012, 10:56 PM   #16
axl
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QuoteOriginally posted by RioRico Quote
Apparently lensmakers just don't think they can profitably make 28/1.4s.
If they can make 24/1.4 profitably then I don't see a reason why they couldn't do it with 28/1.4...

05-03-2012, 01:12 AM   #17
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the 24/1.4 doesn't attract you ?
05-03-2012, 02:12 AM   #18
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QuoteOriginally posted by aurele Quote
the 24/1.4 doesn't attract you ?
It does, but it's 1300 price tag doesn't that's new. Used 24L MkII go for around 1100 and 24L MkI for around 900 which touch above of what I can afford to spend at the moment. Compared to 28/1.8 which go for ~330 when Canon and some 250 in case of Sigma (used prices, new ones are 400 and 335 redpectively)...
05-03-2012, 02:54 AM   #19
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QuoteOriginally posted by axl Quote
It does, but it's 1300 price tag doesn't that's new. Used 24L MkII go for around 1100 and 24L MkI for around 900 which touch above of what I can afford to spend at the moment. Compared to 28/1.8 which go for ~330 when Canon and some 250 in case of Sigma (used prices, new ones are 400 and 335 redpectively)...
I forgot about this ... point of detail...

05-03-2012, 03:48 AM   #20
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Or you can go manual focus, get the canon fd 24/1.4, and convert it to EF.
I have to admit that the canon fd 24/1.4 L is an awesome lens. super sharp wide open, very easy to use.
05-03-2012, 08:01 AM   #21
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QuoteOriginally posted by hoanpham Quote
Or you can go manual focus, get the canon fd 24/1.4, and convert it to EF.
I have to admit that the canon fd 24/1.4 L is an awesome lens. super sharp wide open, very easy to use.
I even saw one and not horribly expensive but I don't know if I'd trust my MF these days with 1D3
05-05-2012, 04:38 AM   #22
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QuoteOriginally posted by TOUGEFC Quote
Dont know about Canon and Sigma but Nikon make a auto-focus 28mm f/1.4D, costs a bit though.
Those are full frame and have some shortcomings.

A 1.4/24 or 28 mm would be a perfect short wide angle lens for APS-C cameras. It should go along with the size and the filter thread of the 1.4/55. I would buy one. If Pentax FF is on the way, the lens will not show up as APS-C design... I would even be happy with a 2/24 mm. Do not mention the FA24 or Sigma lenses, I want a decent modern lens dedicated to APS-C.
05-05-2012, 06:09 AM   #23
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Well, the Samyang 24/1.4 can be nice, but for 600€ it's a bit expensive... but still 1000€ less than the Canikon one. (i know, Samyang are fully manual ...)

05-05-2012, 11:24 AM   #24
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The size, weight, increasingly complex optical design all contribute when you move to faster aperture lenses. I collected a bit of information across some lenses. The Contax (Carl Zeiss) lenses and the Pentax K SMC are all essentially related. You can see as the aperture get larger, the elements increase in size and wieght, even going from older designs and implementations to the newest (Sigma). Then there is the matter of price. The Contax f2.8 is around $250-300, while its f2.0 brother is $1,000.

....................Lens.....................aperture...ele-gps...filter......dia x length.... weight (g)
Contax 28mm F2.8 Distagon F2.8-F22 7-7 55mm 62.5 x 50.0 280
Contax 28mm F2.0 Distagon F2.0-F22 9-8 55mm 62.5 x 76.0 485
Contax 28mm F2.0 Distagon F2.0-F22 9-8 55mm 62.5 x 76.0 530
Pentax SMC 28mm f2.0 F2.0-F22 9-8 52mm --.- x 69.0 423
Sigma 30/f1.4 EX DC HSM F1.4-F16 7-7 62mm 76.6 x 59.0 406

05-06-2012, 04:55 AM   #25
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QuoteOriginally posted by interested_observer Quote
The size, weight, increasingly complex optical design all contribute when you move to faster aperture lenses. I collected a bit of information across some lenses. The Contax (Carl Zeiss) lenses and the Pentax K SMC are all essentially related. You can see as the aperture get larger, the elements increase in size and wieght, even going from older designs and implementations to the newest (Sigma). Then there is the matter of price. The Contax f2.8 is around $250-300, while its f2.0 brother is $1,000.

....................Lens.....................aperture...ele-gps...filter......dia x length.... weight (g)
Contax 28mm F2.8 Distagon F2.8-F22 7-7 55mm 62.5 x 50.0 280
Contax 28mm F2.0 Distagon F2.0-F22 9-8 55mm 62.5 x 76.0 485
Contax 28mm F2.0 Distagon F2.0-F22 9-8 55mm 62.5 x 76.0 530
Pentax SMC 28mm f2.0 F2.0-F22 9-8 52mm --.- x 69.0 423
Sigma 30/f1.4 EX DC HSM F1.4-F16 7-7 62mm 76.6 x 59.0 406

Contax lenses cover a 42 mm image circle - full frame. The current Pentax system is APS-C based - 28 mm image circle - , so a much smaller image circle need to be covered. Your comparison is exaggerating an awful lot!!!
05-06-2012, 10:51 AM   #26
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QuoteOriginally posted by zapp Quote
Contax lenses cover a 42 mm image circle - full frame. The current Pentax system is APS-C based - 28 mm image circle - , so a much smaller image circle need to be covered. Your comparison is exaggerating an awful lot!!!
That post is relevant as I'm after lens to be used on APSH sensor and later (hopefully) on FF sensor from Canon. Not Pentax APSC...so covering 28mm image circle wouldn't be much of use...
05-06-2012, 10:54 AM   #27
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QuoteOriginally posted by interested_observer Quote
The size, weight, increasingly complex optical design all contribute when you move to faster aperture lenses. I collected a bit of information across some lenses. The Contax (Carl Zeiss) lenses and the Pentax K SMC are all essentially related. You can see as the aperture get larger, the elements increase in size and wieght, even going from older designs and implementations to the newest (Sigma). Then there is the matter of price. The Contax f2.8 is around $250-300, while its f2.0 brother is $1,000.

....................Lens.....................aperture...ele-gps...filter......dia x length.... weight (g)
Contax 28mm F2.8 Distagon F2.8-F22 7-7 55mm 62.5 x 50.0 280
Contax 28mm F2.0 Distagon F2.0-F22 9-8 55mm 62.5 x 76.0 485
Contax 28mm F2.0 Distagon F2.0-F22 9-8 55mm 62.5 x 76.0 530
Pentax SMC 28mm f2.0 F2.0-F22 9-8 52mm --.- x 69.0 423
Sigma 30/f1.4 EX DC HSM F1.4-F16 7-7 62mm 76.6 x 59.0 406

I understand the principle of lens making: faster = larger and more expensive, wider = larger and more expensive, newer often = larger and always = more expensive.

But what's not really getting to my head is, if both 24 and 35mm lenses have been made as fast as f1.4 then why there are so few 28/1.4 lenses?!?
05-06-2012, 09:17 PM   #28
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Evening Axl,

I really can't factually answer your question. I can guess - and I do think that I am close. Film bodies really did not need anything faster than f2 from the mid 20's mm to anything wider. The wider angles were used for landscapes and architecture. In these applications a fast f1.x would get you the light, but also drag in a narrow depth of field along with it, which was not necessary.

Pentax really did not provide any type of truly fast lens in these focal lengths. Neither did Zeiss (Contax), where with their wider lenses they went to f4 - and they were still relatively heavy. With the advent of digital, the ISO speeds started to climb, which mitigated the need for a faster lens in terms of light.

I really do not do much of anything with paper thin DoF, and f2.8 is just fine for all of my needs. Heck, f4 is just fine too. Now, I know that my needs do not match everyone's, but the complexity of the lens designs along with the material does tend to challenge the lenses as they stretch down to the wider focal lengths.

05-07-2012, 12:15 AM   #29
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In what case do you need a 28mm f1.4?

If we limited to manual focus lenses, there are several different 28mm lenses, different makers, with different MFD.
Vivitars offer close focus - for thin DOF, close range, face portraits
28/2 gives beautiful half portrait, and with 25cm or 30cm as MFD.

The Konica 28/1.8 has 18cm as MFD and not bigger than nikkor 28/2 nor Pentax K28/2.
I guess that Konica has shorter register distance than pentax and nikon, so the lens design can be as compact but with f1.8.

I think a 28mm f1.4 will come in production, but depends on demand and price.
I don't think I need one, but i will use one if I can get it for cheap. For now I am ok with canon 24/1.4, nikkor 35/1.4, pentax 28/2, konica 28/1.8 and FA35/2, sigma 30/1.4
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