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10-14-2013, 05:44 AM   #16
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QuoteOriginally posted by lytrytyr Quote
While I agree (having myself gone legacy and third-party for 24/2.8 coverage),
I suspect that they won't go any further than the roadmap's Limited zoom to cover that hole,
at least for the APS-C format.
There's a 31 ltd that's one of the best lenses ever made 3mm from 28. I tend to think a 12 and 21 are the gaping holes in prime. Usually a 50% gap is more than acceptable. SO 12 to 18-20 , 20-30, 30-50, 50-70, 70-100.

There is absolutely no reason to have a lens for every 3 mm of coverage. That's why you have zooms.

10-14-2013, 06:56 AM   #17
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QuoteOriginally posted by normhead Quote
There's a 31 ltd that's one of the best lenses ever made 3mm from 28.
But a big difference in angle of view from the 24-25s Robbie and I were contemplating.

QuoteOriginally posted by normhead Quote
I tend to think a 12 and 21 are the gaping holes in prime.
What about the DA 21?
10-14-2013, 07:06 AM   #18
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So..... K-3 still not letting user choose if they want to use screw drive or SDM? If Ricoh open this 'option' up, many will be happy.
10-15-2013, 11:04 AM   #19
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Pentax needs to either ditch SDM and replace it with DC, or ditch screwdrive AF, replace it with DC motors, and improve SDM's unreliability and slowness (reserved for DA* lenses I guess).

10-15-2013, 11:42 AM   #20
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QuoteOriginally posted by jrcastillo Quote
I wonder if they should just ditch the idea of SDM altogether and ask Sigma to build Pentax lenses with HSM or something. This will considerable reduce time to market of a revised "DA* 16-50 II" and introduce other new lenses like the 18-35, 70-200, under pentax brand... and most likely with weather sealing.

Smart companies do this every time... There is nothing wrong in recognizing that someone else's tech is better than yours. Just look at Apple with Siri (adquired from SRI), Microsoft with their Kinect (adquired from a company called Primesense) and the list would go ON and ON and ON....... I don't own a SDM lens, but the more I read the less I want one. Just the fact that they're so famous for its low quality motor, I wouldn't throw $1k in a lens I know most likely die tomorrow. You can argue that you own 1 SDM for 3 years with no problem... but unfortunately, the bad quality fame of the SDM is just too big. And until they fix that fame (even changing the name to something like SDM2 would help) pentax lineup will not be complete as SDM is not even an option.

Just imagine if Pentax would take something as simple as Sigma's 17-70 C and add weather sealing to it and make something like "Pentax DA 17-70 2.8-4 HSM Macro WR". Yes it would mean that they will eat up lenses they have like the 16-45 F4 but to be honest is better to kill your own product than to have someone else kill it for you. Or do you think that Pentax did not know that coming with K-3 was going to kill K-5II sales? Yes of course they know it, but is better to kill YOUR K-5II sales with YOUR K-3 rather than Nikon kill YOUR K-5II sales with THEIR D7100 or D7200. So is better to have Sigma make your lenses (at least the 16-50 2.8 or something in that range) put Pentax on them, Kill the 16-45, and most likely the 16-50... Rather than be offering laughable product and have other companies kill your product.

I know pentax has done this in the past with Tamrom lenses. Why no do it know when SDM is clearly NOT working 100% yet?
What lens is there that will truly match the K-3 in 16-70 range? I wouldn't really buy a 16-50 2.8 when I know (from reading This REVIEW ) that the pentax one costs 2X its rivals and is the worst of the batch!

Anyway, you can argue that pentax has the most comprehensive apsc lens offering, but in reality, nobody needs ALL the lenses... who cares if there are 1,000 different lenses when you cannot really find one(1) that is as good as a 17-70 Contemporary from sigma w/o having SDM problems? yes you cannot compare the 16-50 with sigmas 17-70.. but precisely!!!! how would I buy the 16-50 (2x the cost of the sigma) when i know it has laughable SDM which can die within a day of use?
Agree 100% here. I want a constant aperture zoom (f/2.8 or 4) with a roughly 17-70 focal length. At the moment, all of Pentax's offerings in this range are flawed in one way or another. The DA*16-50 f/2.8 and 17-70 f/4 both have SDM, plus the DA* does not seem up to the task optically considering its price. The older DA 16-45 seems to be pretty good optically, but is missing an in-lens focus motor and has a bit short range. Tamron and Sigma both seem to have competent offerings in their 17-50 f/2.8 lenses, although they are both missing WR and quick-shift and Tamron is missing the in-lens focus motor. I've been investigating these options for some time and the Sigma comes closest to what I need. I just wish it had Pentax written on it and came with WR and quick-shift.

My dream "everyday" lens would be:
- 16-70 f/4 (I will sacrifice one stop to keep the weight reasonable)
- in-lens, quiet focus motor (no SDM!) that locks focus quickly and accurately
- WR
- quick-shift manual focus
- competent image quality across all focal lengths and apertures (not looking for perfection, but no major weaknesses tolerated)
- 49mm filter thread (just kidding )

I'm going to order the Sigma soon and wait to see what Pentax brings out in the next year. I'm still very happy with the image quality of my K-5 so I don't plan on upgrading immediately to the K-3, I just need a good replacement for the kit lens and a few Limiteds to go with the lenses I already have (see my sig).
10-16-2013, 07:21 AM   #21
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QuoteOriginally posted by normhead Quote
There's a 31 ltd that's one of the best lenses ever made 3mm from 28. I tend to think a 12 and 21 are the gaping holes in prime. Usually a 50% gap is more than acceptable. SO 12 to 18-20 , 20-30, 30-50, 50-70, 70-100.

There is absolutely no reason to have a lens for every 3 mm of coverage. That's why you have zooms.
Personally I would like to see a 12 prime. We have the 14 but that's too close to the DA* 16-50 I already own and in the super wide category I personally don't see the need for a zoom. Most folks with super wide zooms shoot at the widest setting anyway ...so why a zoom.
10-16-2013, 07:32 AM   #22
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Look through the Sigma 8-16 thread. I think you'll see lots of images taken from 9-16. 16 mm on an 8-16 is just as useful as on a 16-50, with the 16 mm on the SIgma being better corrected for barrel distortion and chromatic aberration.) Before I bought mine I tried both the DA 15 and DA*16-50 and decided not to buy either. And the sigma 8-16 is free of barrel distortion right down to 12 mm, and very low CA values through it's whole range. It's defintiely a "stack of primes" kind of lens, the only drawback being it feels like you are carrying a stack of primes.

Last edited by normhead; 10-16-2013 at 10:22 AM.
10-16-2013, 08:35 AM   #23
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QuoteOriginally posted by MikePerham Quote
Personally I would like to see a 12 prime. We have the 14 but that's too close to the DA* 16-50 I already own and in the super wide category I personally don't see the need for a zoom. Most folks with super wide zooms shoot at the widest setting anyway ...so why a zoom.
Sigma 10-20 is basically a 10mm prime. Unless you considerably sacrifice speed drastically I dont think it's easy to design a compact 12mm prime for APSC. DA 15 is basically the only lens in its class, it has no friends ;_;

10-16-2013, 09:37 AM   #24
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QuoteOriginally posted by Andi Lo Quote
Unless you considerably sacrifice speed drastically I dont think it's easy to design a compact 12mm prime for APSC.
I speculate idly about a DA 12 XS to go on the K-01,
like the Voigtlaender Heliar 12/5.6:

Voigtlander SL 12/5.6 15/4.5

It would need color/vignetting correction at the edges,
done in the camera or Silkypix.
10-16-2013, 10:00 AM   #25
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QuoteOriginally posted by lytrytyr Quote
I speculate idly about a DA 12 XS to go on the K-01,
like the Voigtlaender Heliar 12/5.6:

Voigtlander SL 12/5.6 15/4.5

It would need color/vignetting correction at the edges,
done in the camera or Silkypix.
Amazing, I didnt know such a thing existed, and its FF to boot. Like you said it seems that the vignetting is severe, but the idea of a compact 12mm full frame lens is great. Maybe an aps 8mm/8 isnt that far off?

You learn something everyday
10-16-2013, 10:26 AM   #26
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QuoteOriginally posted by Jeff Charles Quote
The K-3 may have world-class AF (although we do not know for sure yet), but lenses are part of the AF system, and the Pentax system may need an upgrade to two essential ones...
Pentax has built lenses before with technology that current camera bodies couldn't access. Later on, the cameras caught up. One example: the DA lenses all had the data to correct for CA and distortion, well before the cameras could access it. You may find the K-3 has the ability to work with SDM lenses better than older bodies.

If not, some kind of SDM II makes sense, just like the new HD coatings make sense. The K-3 is supposed to be an APS-C flagship, and APS-C needs these two lenses.
10-17-2013, 03:08 AM   #27
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QuoteOriginally posted by Just1MoreDave Quote
You may find the K-3 has the ability to work with SDM lenses better than older bodies.
If not, some kind of SDM II makes sense, just like the new HD coatings make sense.


I would argue that SDM II (or another technology) is needed regardless how current SDM lenses perform on K-3. The major issue with SDM is reliability, or lack thereof, and attaching an SDM lens to a different body is going to have zero effect on SDM reliability. The problem is in the lens.
10-17-2013, 03:14 AM   #28
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QuoteOriginally posted by Adam Quote
IMO they should slowly start moving away from screwdrive AF, as we can do better these days.
If Pentax did that, it would be completely gone at this point. And Pentax has proven that even though it can be done better than screw drive, it couldn't do it with SDM.
10-17-2013, 07:25 AM   #29
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QuoteOriginally posted by snake Quote
If Pentax did that, it would be completely gone at this point. And Pentax has proven that even though it can be done better than screw drive, it couldn't do it with SDM.


QuoteOriginally posted by cbope Quote
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I would argue that SDM II (or another technology) is needed regardless how current SDM lenses perform on K-3. The major issue with SDM is reliability, or lack thereof, and attaching an SDM lens to a different body is going to have zero effect on SDM reliability. The problem is in the lens.
Lots of speculation here. Apparently, screw drive is faster and quieter on the new K-3 body, I'm not sure SDM and DC are needed except on longer lenses and zooms. It looks like screw drive might be more adaptable to change than SDM.

What is the industry standard for failure of electric motor driven lenses? Is this a Pentax issue, or is this a function of putting electric drive in any lens by any manufacturer? I can't imagine anyone would put a motor in a lens that was so over -engineered none of them would ever fail. No one would want to pay for that. At some point SDM will be re-engineered and improved.. it already has been... and I'm sure it's an ongoing process. There's sure to be a few guys somewhere trying to fit a better electric motor into the tiny little space the lens design team gave them.

The funny thing is guys saying "Pentax has to improve this" at the same time it's almost certain Pentax is paying people to improve it. You just have to wait for it to come out. If SDM isn't good enough for you, don't buy it. The next greatest, best thing will be out soon enough for most of us.
10-17-2013, 10:19 AM   #30
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QuoteOriginally posted by normhead Quote
Lots of speculation here.
I'm sorry, it is not speculation to say SDM failure on specific Pentax lenses is outside what is considered normal. And since there is no specific point in time, serial number or other confirmation that you are getting a "good" SDM lens, it's not worth the risk to me. I don't live next door to a Pentax repair facility. Sending a lens off to another country for repair and dealing with customs and resulting paperwork is just not worth it.

There are too many reports of lenses only a few months old with dead SDM motors, and people whose lenses have been at repair facilities for MONTHS, still awaiting parts. Is Pentax paying customers for the time that they cannot use their lenses, because they are waiting for parts to repair a lens? If it's my primary lens, am I just supposed to stop photographing?

It's interesting you bring up motor failure rates in the industry, but the problem is that no lens manufacturer will publish them. Would be nice though.

My concerns are nothing to do with AF speed... I don't photograph sports or BIF so I could really care less about having the absolute fastest AF performance. All I want is AF that locks on to a subject with a decent speed and accuracy and something quieter than screwdrive. Any relative speed differences between screwdrive on a new body vs. my K-5 are irrelevant to me.

I won't comment any more on this matter, and I won't be buying any lenses with the current SDM system. I don't intend to piss off anyone, but it really bugs me when someone implies "there is no problem", when clearly there is a problem.
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