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03-04-2009, 06:20 PM   #46
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Those that claim f/4 is too slow for an rectilinear ultra-wide have simply little idea how difficult it is to design a fast ultra wide angle lens, especially to correct barrel distortion, even frame resolution and resistance to flare. One can handhold a 15mm lens pretty easy due to the short focal length, so there is little disadvantage to go f/4 especially if it is well corrected lens.

03-04-2009, 06:43 PM   #47
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QuoteOriginally posted by creampuff Quote
Those that claim f/4 is too slow for an rectilinear ultra-wide have simply little idea how difficult it is to design a fast ultra wide angle lens, especially to correct barrel distortion, even frame resolution and resistance to flare. One can handhold a 15mm lens pretty easy due to the short focal length, so there is little disadvantage to go f/4 especially if it is well corrected lens.
I agree. For a 15mm focal length, especially that size, that ain't half bad. Besides, isn't the 14 that already exists of the bigger and faster variety?

Nice, but even as kind of a speed-fiend in lenses, I'd never *carry* a wide lens that big... even if I'd conceivably prefer it once it was on there. This 15, I might conceivably buy and carry and use, ...not as a priority, but if I were buying full-priced lenses pretty regularly.
03-04-2009, 08:40 PM   #48
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Given the focal length is only 15mm + SR, we can get away with a pretty low shutter speed so f4 doesn't sound like a huge problem. For me a useful lens is one that I'm willing to lug around or mount on the camera.

I've never owned any wide angle lens so plz correct me if I'm wrong.
03-04-2009, 09:15 PM   #49
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QuoteOriginally posted by Kei Quote
Given the focal length is only 15mm + SR, we can get away with a pretty low shutter speed so f4 doesn't sound like a huge problem. For me a useful lens is one that I'm willing to lug around or mount on the camera.

I've never owned any wide angle lens so plz correct me if I'm wrong.
In my experience once you go below 1/30s 1/15s the SR or wider focal length really don't help that much. Usually your heart beat and breathing will create enough shake.

If its too dark I use continuous mode and shot 4-6 shots. That way you can almost always get one sharp photo.

03-05-2009, 02:39 AM   #50
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QuoteOriginally posted by Arpe Quote
Yet another f4 lens from Pentax. Why do they do that?
Because a DA15/2,8 should compete with DA14/2,8.
Limited series are small and light, DA series are fast and big, DA* SDM are fast, big, silent and weather sealed. Different types for different purpose.
03-05-2009, 03:14 AM   #51
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QuoteOriginally posted by whatever7 Quote
In my experience once you go below 1/30s 1/15s the SR or wider focal length really don't help that much. Usually your heart beat and breathing will create enough shake.

If its too dark I use continuous mode and shot 4-6 shots. That way you can almost always get one sharp photo.
You need to learn to hold your breath in the right moment - my record at 16mm is 1/3 second without SR (I had a door frame to lean on, though).

I agree that continuous mode can be useful, I use this trick a lot on my Optio W10.
03-05-2009, 03:32 AM   #52
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Current DA Limiteds line-up:

DA 70 F2.4
DA 40 F2.8
DA 35 F2.8
DA 21 F3.2
DA 15 F4

All have 49mm filter size, all the released ones are optically excellent w/ great built quality. I'd assume the DA15 will be another success for a pancake lens Have you ever seen a 15mm super wide angle lens as small as this one?

The MSRP is only $650USD. I'm guessing this lens will have a price of $400 to 450USD soon after it comes to market (DA70 has a $600 MSRP but only selling for $400 in many online stores now). This DA15 lens would probably become the most sold DA limited lens
03-05-2009, 05:32 AM   #53
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QuoteOriginally posted by creampuff Quote
Those that claim f/4 is too slow for an rectilinear ultra-wide have simply little idea how difficult it is to design a fast ultra wide angle lens, especially to correct barrel distortion, even frame resolution and resistance to flare.
Except that didn't Pentax design a f/3.5 for full frame in the same focal length? With less glass you'd think they could do the same at f/2.8. Especially for the price. (I do not mind giving up a little size for another stop.)

This is true of the other DA Limiteds as well.

Don't get me wrong, I am sure this lens will be very popular. Outside of our community I would not bother nit-picking. But it is far less compelling to me personally.

03-05-2009, 07:17 PM   #54
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QuoteOriginally posted by frank Quote
All have 49mm filter size, all the released ones are optically excellent w/ great built quality. I'd assume the DA15 will be another success for a pancake lens Have you ever seen a 15mm super wide angle lens as small as this one?
Well, I know this isn't a fair comparison, but obviously yes (second lens section on page). I've been sorely tempted to get second-hand copies of a rangefinderless Bessa L and this 100-gram lens ($300- $400 total?), and go take 110-degree FOV pictures. --Dave
03-05-2009, 07:25 PM   #55
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QuoteOriginally posted by Argenticien Quote
Well, I know this isn't a fair comparison, but obviously yes (second lens section on page). I've been sorely tempted to get second-hand copies of a rangefinderless Bessa L and this 100-gram lens ($300- $400 total?), and go take 110-degree FOV pictures. --Dave
Well, you are right about that. Those rangefinder Voigtlander lenses are quite small and compact. If only there is a cheap rangerfinder digital camera to mount them on ...
03-06-2009, 08:47 PM   #56
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A new 15mm Pentax lens, eh?

What's the Tokina version gonna be called?
03-06-2009, 09:50 PM   #57
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QuoteOriginally posted by lithos Quote
A new 15mm Pentax lens, eh?

What's the Tokina version gonna be called?
Probably the same as the Tokina version of the DA35mm macro...
03-06-2009, 10:15 PM   #58
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QuoteOriginally posted by Kei Quote
Ouch! $650 USD...with the CDN exchange rate down the toilet its way out of my reach. I will get it right away if its about the same price as the DA 35 ltd. Oh well.....back to the waiting game...
If it came out 10 months ago it would have been $300 CA (OK..not quite). Funny how the currency speculation changes things.
03-07-2009, 07:13 AM   #59
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QuoteOriginally posted by Sean Nelson Quote
Probably the same as the Tokina version of the DA35mm macro...
...or the 16-50 SDM, or the 50-135 SDM...
03-07-2009, 08:51 AM   #60
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been thinking about it, the 15 and the 35 would make a sick travel kit
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