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11-21-2013, 03:42 PM   #841
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When can we expect to see some [new] output from this lens on a K-3?

PS: Here's a "review" http://www.digitalcamerareview.com/default.asp?newsID=5454&news=pentax+ricoh...e+zoom+K-5+IIs

I don't like the bokeh produced by this lens all that much as circular features have pronounced edges.


Last edited by bossa; 11-21-2013 at 04:02 PM.
11-21-2013, 04:46 PM   #842
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QuoteOriginally posted by bossa Quote
don't like the bokeh produced by this lens all that much as circular features have pronounced edges.
Even the FA77 can do that, I have current Canon and Nikon glass that does the same, Leica lenses don't seem to do it.
11-21-2013, 04:59 PM   #843
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QuoteOriginally posted by Mr Spocko Quote
SIze is not always an issue to many buyers, despite moans from some there are APS-C lenses that are quite a bit more compact and less weight then some FF equivalents.
As for flare well we shall see, again I've rarely had issues with flare even with older glass..some actually like a bit.

No I don't like that site much but hey the price is a bit silly for this lens. Worth pointing out they reviewed the K-3 and a number of limited lenses and gave them good marks. I'd wait for some real reviews though, but that won't change the not that fast, expensive, limited range comments it is quite likely to get from many review sites. I wouldn't hold out for a bunch of gold star, editors choice rewards etc etc it's not likely to get that.

As for the comments on speed we've been down this road before. Who finds their 50mm f1.4 huge, bulky and heavy? Ditto 35mm primes too
If I were Pentax I'd re-work some of the limited range say make the 40mm f2 which would broaden it's appeal even to zoom users.
Based on your argument the DA14f2.8 would be far more popular than the DA15f4. Max aperture is not the only selling point of a lens. The whole set of limiteds is slow compared to their competitors and they are all very well liked.

Why would anyone find a 50f1.4 bulky and heavy? It's 220 grams. A 20-40mm lens that was f2 at the 40mm end would be huge on the other hand. the new Sigma lens is a tank compared to the Pentax limited. 810 grams vs 283 grams. These are 2 very different lenses and I'm not sure why people people continue to mention these as competitors.
11-21-2013, 05:40 PM   #844
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QuoteOriginally posted by bossa Quote
When can we expect to see some [new] output from this lens on a K-3?

PS: Here's a "review" Pentax HD 20-40mm f2.8-4 DA Limited Lens: Image Gallery and First Look

I don't like the bokeh produced by this lens all that much as circular features have pronounced edges.
I guess that's diffraction at work. Actually, it's the fact that the highlight bokeh isn't completely circular that bothers me more, but the general OOF rendering looks OK to me.

Otherwise, there's no doubting the sharpness at a variety of focal lengths is pretty good for this lens, judging by these shots. One hopes that the price will become more reasonable over time. AF performance will be interesting, too.

11-21-2013, 07:43 PM   #845
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The highlights turn into donuts (doughnuts) at smaller apertures too it seems.
11-22-2013, 02:20 AM - 1 Like   #846
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QuoteOriginally posted by Parallax Quote
Here's my dilema -
I have a 15Ltd, 31Ltd, 40Ltd, and a Sigma 18-250. I am torn between adding the Sigma 18-35 and the 20-40Ltd. If I get the 18-35 I can't really justify keeping the 31, so I could sell it and get the 18-35 making it, for practical purposes, free.
OTH, it would be a $1,000.00 expenditure, but if I get the 20-40 then none of the lenses I have, including the 31 are rendered superfluous, The 40Ltd is faster than the 20-40 (at 40mm), the 31 is much faster, and the 15 fits with either scenario.
I think the first step is going to be to pick up a K-5 on Black Friday.
Come to think of it, with the low-light capability of the K-5 I could still sell the 31 and get by with the 20-40.
Now my head hurts.........................

According to Photozone:

• the FA 31mm @ f1.8 has depth-of-field of f2.7 when compared to full frame

• the DA 18-55mm @ f3.5 has depth-of-field of f5.3 when compared to full frame

So the 20-40mm will not be able to produce the shallow depth of field effect that the 31mm can.


Compact limiteds are small and light but the "smaller" apertures have downsides: darker VF image, "slower" auto-focus and not as shallow depth of field effect.


This is why Pentax really must produce a fast set "standard" focal length lenses:

• DA f2/18mm (~f3/28mm FOV & DOF equiv.)

• DA f2/24mm (~f3/35mm FOV & DOF equiv.)

• DA f1.4/35mm (~f2.1/50mm FOV & DOF equiv.)

• DA f1.8/35mm (~f2.7/50mm FOV & DOF equiv.)

• DA f1.8/60mm (~f2.7/90mm FOV & DOF equiv.)


R
11-22-2013, 02:29 AM   #847
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QuoteOriginally posted by Iberia Quote
According to Photozone:

• the FA 31mm @ f1.8 has depth-of-field of f2.7 when compared to full frame

• the DA 18-55mm @ f3.5 has depth-of-field of f5.3 when compared to full frame

So the 20-40mm will not be able to produce the shallow depth of field effect that the 31mm can.


Compact limiteds are small and light but the "smaller" apertures have downsides: darker VF image, "slower" auto-focus and not as shallow depth of field effect.


This is why Pentax really must produce a fast set "standard" focal length lenses:

• DA f2/18mm (~f3/28mm FOV & DOF equiv.)

• DA f2/24mm (~f3/35mm FOV & DOF equiv.)

• DA f1.4/35mm (~f2.1/50mm FOV & DOF equiv.)

• DA f1.8/35mm (~f2.7/50mm FOV & DOF equiv.)

• DA f1.8/60mm (~f2.7/90mm FOV & DOF equiv.)


R
Those will (would) rather be DFAs IMO (in FF corresponding focals).
11-22-2013, 02:38 AM   #848
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QuoteOriginally posted by Iberia Quote
This is why Pentax really must produce a fast set "standard" focal length lenses:

• DA f2/18mm (~f3/28mm FOV & DOF equiv.)

• DA f2/24mm (~f3/35mm FOV & DOF equiv.)

• DA f1.4/35mm (~f2.1/50mm FOV & DOF equiv.)

• DA f1.8/35mm (~f2.7/50mm FOV & DOF equiv.)

• DA f1.8/60mm (~f2.7/90mm FOV & DOF equiv.)


R
Can I preorder some of those? Those would be excellent, this is what Pentax should have done a long time ago. But according to Pentax, users are not interested in fast lenses anymore due to the high ISO capabilities of modern sensors. Which is a wrong conclusion, of course.

11-22-2013, 02:50 AM   #849
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QuoteOriginally posted by Iberia Quote
Compact limiteds are small and light but the "smaller" apertures have downsides: darker VF image, "slower" auto-focus and not as shallow depth of field effect.


This is why Pentax really must produce a fast set "standard" focal length lenses:

• DA f2/18mm (~f3/28mm FOV & DOF equiv.)

• DA f2/24mm (~f3/35mm FOV & DOF equiv.)

• DA f1.4/35mm (~f2.1/50mm FOV & DOF equiv.)

• DA f1.8/35mm (~f2.7/50mm FOV & DOF equiv.)

• DA f1.8/60mm (~f2.7/90mm FOV & DOF equiv.)


R
You clearly never handled the DA 40mm/f2.8 Ltd since otherwise you would know that that is one off the fastest auto focus lenses for Pentax.

You'r lenslist is pretty, but be serious 18mm/f2.0!!!!!!!! It is cheaper to buy a full frame camera with a standard 28mm/f2.8 lens.
11-22-2013, 03:17 AM   #850
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QuoteOriginally posted by abacus07 Quote
Based on your argument the DA14f2.8 would be far more popular than the DA15f4. Max aperture is not the only selling point of a lens. The whole set of limiteds is slow compared to their competitors and they are all very well liked.
Max aperture is not so much a selling point for an ultra-wide-angle lens. Imagine the 17-70/4 would be similarly priced to the 16-50/2.8. Which one do you think would sell better, even with the increased range and lighter weight of the 17-70?
11-22-2013, 03:23 AM   #851
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QuoteOriginally posted by starbase218 Quote
Max aperture is not so much a selling point for an ultra-wide-angle lens. Imagine the 17-70/4 would be similarly priced to the 16-50/2.8. Which one do you think would sell better, even with the increased range and lighter weight of the 17-70?
You are right, but a zoom is not an ultra-wide only.

Besides, 17mm is not ultra-wide in an APS "cropped-sensor" format since the FOV is equiv. to a 34mm, perhaps a wide-normal.

For my work, I would rather have f2,8 @ 50mm than f4 @ 70mm.
That's is why I chose the Tamron 28-75mm.

R
11-22-2013, 03:28 AM   #852
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QuoteOriginally posted by RonHendriks1966 Quote
You clearly never handled the DA 40mm/f2.8 Ltd since otherwise you would know that that is one off the fastest auto focus lenses for Pentax.
I haven't, only the FA 43mm…

But I have the impression that if less light is entering the chamber then the AF will not work as fast or as accurately.
I could be wrong, though...

QuoteOriginally posted by RonHendriks1966 Quote
You'r lenslist is pretty, but be serious 18mm/f2.0!!!!!!!! It is cheaper to buy a full frame camera with a standard 28mm/f2.8 lens.
You are thinking full-frame size/weight/prices but these are "cropped-format" DA lenses.

And if (or perhaps while) Pentax has chosen to stay away from full-frame, then it must provide the necessary tools (i.e. focal lengths) for a "flexible" photography system.


I know these are mirrorless-body lenses but Olympus can produce and sell a small and light 12mm f2 (24mm FOV equiv.) with metal housing for 560£/690€ while Pentax sells a 21mm f3,2 (31,5mm FOV equiv.) for 580£/600€.

And they also have two more metal housing lenses: the 17mm f1,8 (34mm FOV equiv.) and the 45mm f1,8 (34mm FOV equiv.).


R
11-22-2013, 04:28 AM   #853
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QuoteOriginally posted by Iberia Quote
I haven't, only the FA 43mm…

But I have the impression that if less light is entering the chamber then the AF will not work as fast or as accurately.
I could be wrong, though...



You are thinking full-frame size/weight/prices but these are "cropped-format" DA lenses.

And if (or perhaps while) Pentax has chosen to stay away from full-frame, then it must provide the necessary tools (i.e. focal lengths) for a "flexible" photography system.


I know these are mirrorless-body lenses but Olympus can produce and sell a small and light 12mm f2 (24mm FOV equiv.) with metal housing for 560£/690€ while Pentax sells a 21mm f3,2 (31,5mm FOV equiv.) for 580£/600€.

And they also have two more metal housing lenses: the 17mm f1,8 (34mm FOV equiv.) and the 45mm f1,8 (34mm FOV equiv.).


R
I don't think that APS-C only lenses get that much smaller than full frame lenses, considering that Pentax has chosen to keep a full frame mount and reigstration distance. If Pentax chose a different mount and a shorter registration distance, then of course they could create smaller lenses for APS-C. What Pentax has done is just make slower lenses and that has kept lens size small.

That said, I don't want a 14mm f2.8 lens. When I shoot landscapes, I want more depth of field. Foreground to back ground in focus. And to do that, you usually have to be at f8 to 11 on APS-C. I really think that this lens will be adequately fast for the purposes of those who will use it.
11-22-2013, 04:32 AM   #854
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QuoteOriginally posted by Rondec Quote
I don't think that APS-C only lenses get that much smaller than full frame lenses, considering that Pentax has chosen to keep a full frame mount and reigstration distance. If Pentax chose a different mount and a shorter registration distance, then of course they could create smaller lenses for APS-C. What Pentax has done is just make slower lenses and that has kept lens size small.

That said, I don't want a 14mm f2.8 lens. When I shoot landscapes, I want more depth of field. Foreground to back ground in focus. And to do that, you usually have to be at f8 to 11 on APS-C. I really think that this lens will be adequately fast for the purposes of those who will use it.
I agree that a 14mm f2,8 (21mm FOV equiv.) lens doesn't make much sense, that is why I didn't put one in my list.

And to be honest I don't think that an 18mm (~28mm FOV equiv.) lens has to be f2; f2,8 would be fine.

R
11-22-2013, 06:11 AM   #855
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QuoteOriginally posted by Iberia Quote
According to Photozone:

• the FA 31mm @ f1.8 has depth-of-field of f2.7 when compared to full frame

• the DA 18-55mm @ f3.5 has depth-of-field of f5.3 when compared to full frame

So the 20-40mm will not be able to produce the shallow depth of field effect that the 31mm can.


R
I appreciate your input, but acquiring razor thin DOF is not an issue, or even desirable for me. If somebody could bend the laws of physics and produce an f1.4 lens that yielded the same DOF at 1.4 that it does at 2.8 or 4, I'd pay big bucks to get it. With the high ISO capabilities of the current cameras, for my purposes (other's mileage may vary) lenses faster than 2.8 have far less appeal than they used to. In fact, now that I've written that, and reread it, I do believe I've just decided on the 20-40 over the Sigma 18-35.
I know the super shallow DOF junkies may gasp at this, but I have no need to take pictures with freckles in focus and the skin they're on out of focus.
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