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01-09-2014, 07:11 PM   #46
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K - (not a real Pentax designation) - the first iteration of Pentax's K-mount bayonet mount lenses. Proper name is typically "SMC Pentax (f/#)/(Focal Length)" -- SMC Pentax 1:1.4/50, but that can vary by lens.

Also - here's another "more than you want to know" resource: K-Mount Page The discussion of the history of the K-mount technology and the contact patterns is especially useful. The section on the "crippled" KAF mount partially explains how the current dSLR bodies interact with the manual aperture lenses.


Last edited by monochrome; 01-10-2014 at 07:30 AM.
01-10-2014, 04:39 AM   #47
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QuoteOriginally posted by arkav Quote
SDM - in lens motor - seems to have a reputation for poor reliability
The DA* 16-50/2.8 and the DA* 50-135/2.8 developed a bad reputation but many other SDM lens models appear to be reliable.

There has been reports of Pentax having fixed the SDM problems recently, but I'm not sure whether they have any merit.

Last edited by Class A; 01-10-2014 at 07:51 PM.
01-10-2014, 07:42 AM   #48
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QuoteOriginally posted by Class A Quote
The DA 16-50/2.8 and the DA 50-135/2.8 developed a bad reputation but many other SDM lens models appear to be reliable.

There has been reports of Pentax having fixed the SDM problems recently, but I'm not sure whether they have any merit.
I haven't seen any recent reports of newly bought DA* having failed SDM for a long time. I would still feel more comfortable if they re-released those two as DA* xx-xx f/2.8 II with DC motors. I think the fix without a changed model impairs the residual value of lenses people purchase new. The other thing is that I have heard that compared to DC the SDM has a little bit of input lag between when you ask it to start autofocusing and when it actually starts autofocusing.
01-10-2014, 10:10 AM   #49
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I only have one SDM lens, a DA* 60-250 which I bought used maybe 6 months ago. It's been rock solid for me! It's also a fantastic lens.

01-10-2014, 05:40 PM   #50
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QuoteOriginally posted by mikemike Quote
I haven't seen any recent reports of newly bought DA* having failed SDM for a long time. I would still feel more comfortable if they re-released those two as DA* xx-xx f/2.8 II with DC motors. I think the fix without a changed model impairs the residual value of lenses people purchase new. The other thing is that I have heard that compared to DC the SDM has a little bit of input lag between when you ask it to start autofocusing and when it actually starts autofocusing.
Yeah considering that the K-3 is supposedly amazing at AF, and considering that I am currently used to Nikon's pretty awesome and reliable AF that can nail anything in low light, ...I'm probably going to want to only use the absolute best focusing lenses for the K-3, if I am going to use it professionally for wedding photojournalism.

(Of course if I only use it for adventure photography, I don't really care much at all about AF and care much more about portability and weather resistance!)

Is there anywhere that lists lenses by whether they have DC autofoucs or SDM autofocus? How about a list of all the WR lenses?

Just for reference, I totally geek out about sites like this for Nikon lenses. Nikon Lenses (Every Nikon lens ever made, all in one list. Woohoo!)
01-10-2014, 07:50 PM   #51
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QuoteOriginally posted by Matthew Saville Quote
Is there anywhere that lists lenses by whether they have DC autofoucs or SDM autofocus?
To the best of my knowledge, there are currently only two DC lenses, the 18-135/3.5-5.6 and the new 20-40/2.8-4.0.

I wouldn't worry about SDM in general. While it is always a micro-motor (rather than the more sophisticated ring motors of higher-end HSM Sigma lenses), reliability does not appear to be a problem, except for a few select lens models (the 16-50/2.8 and the 50-135/2.8 having been the main offenders).

Regarding an overview of Pentax lenses, I really like the overview and individual information available from Bojidar Dimitrov's Pentax K-Mount Pages.

You'll also find a good overview an in particular many user reviews in Pentaxforums' lens review database.

I'm not aware of a dedicated list for WR lenses, but they are easy to identify by either the "DA*" or the "WR" monikers in the lens model description.
01-12-2014, 04:21 AM   #52
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Hi,

I have just joined the Pentax forum after years of Nikon - with its endless cameras and glasses but without joy.

Bought K3 and DA* 16-50 zoom. I am an exclusive RAW shooter, convert RAW on Pentax utility software into JPEG highest quality and then run a final edit in Nikon Capture NX2 software (v. good product).

Will never look back to Nikon - Pentax is the way to go after 2 months of its use. Cannot fault it even though there are a few minor improvements possible (as usually always are). The only one bitch is 6 hrs battery charging time - nuisance - it should be 2 hrs max nowadays.

Light gear, total weather resistant (I operate in dry temp up to 50C Kurdistan and wet Papua New Guinea).

Quality of shots up to 3200 ISO is excellent, and 6400 still very good.

Planning to buy another Pentax body and another DA* tele zoom up to 250mm to have permanent couplings (hate changing glass).

Occasionally, I still use my Nikon gear but only for sport shots in D3 continuous traceable mode.

The most important - joy of photography returned to my life with Pentax.

A need for a full frame is a myth for vast majority of shooters, including a pro guys like you, in my humble opinion.

K3 will give you all you want from its sensor without FX enigma (and its associated heavy weight gear).

Hope that some of the above may be of assistance.

Cromer
01-14-2014, 08:11 PM   #53
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Alright, I pulled the trigger on a (loaner) K-3 plus the 15mm f/4 and 40mm f/2.8 SMC P-DA (?) Plus, of course, the O-GPS1.

Hopefully it will arrive in time to test out at a wedding in a few weeks in Hawaii, plus a trip to somewhere remote for some astro landscape testing...

Take care everybody, and I'll look forward to most likely joining this community permanently very soon!
=Matt=

01-14-2014, 08:50 PM   #54
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QuoteOriginally posted by Matthew Saville Quote
Alright, I pulled the trigger on a (loaner) K-3 plus the 15mm f/4 and 40mm f/2.8 SMC P-DA (?) Plus, of course, the O-GPS1.

Hopefully it will arrive in time to test out at a wedding in a few weeks in Hawaii, plus a trip to somewhere remote for some astro landscape testing...

Take care everybody, and I'll look forward to most likely joining this community permanently very soon!
=Matt=
Matt - I hope you really enjoy the K3 and lenses. The 15/4 Limited is a fantastic little lens.

I for one will look forward to hearing how you go, and your impressions.

I will look forward to seeing you around the forum
01-14-2014, 10:53 PM   #55
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QuoteOriginally posted by Matthew Saville Quote
Alright, I pulled the trigger on a (loaner) K-3 plus the 15mm f/4 and 40mm f/2.8 SMC P-DA (?) Plus, of course, the O-GPS1.

Hopefully it will arrive in time to test out at a wedding in a few weeks in Hawaii, plus a trip to somewhere remote for some astro landscape testing...

Take care everybody, and I'll look forward to most likely joining this community permanently very soon!
=Matt=
That's my small and light kit exactly (well, no gps for me). Nice choice!
01-15-2014, 08:02 AM   #56
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QuoteOriginally posted by Matthew Saville Quote
Alright, I pulled the trigger on a (loaner) K-3 plus the 15mm f/4 and 40mm f/2.8 SMC P-DA (?) Plus, of course, the O-GPS1.

Hopefully it will arrive in time to test out at a wedding in a few weeks in Hawaii, plus a trip to somewhere remote for some astro landscape testing...

Take care everybody, and I'll look forward to most likely joining this community permanently very soon!
=Matt=
That shouldn't take up much space in your carry-on.
01-20-2015, 09:04 AM   #57
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hello Matt

I too struggled with the idea of switching to Pentax from 25+ years with Nikon, the latest being the D300. I made the switch to the K-3 and have no regrets at all: it is a great camera with many features that the best Nikons (or Canons) don't offer. As SFMike mentioned I would also recommend the O-GPS-1 astrotracer for tracking stars with exposures up to 5 minutes. I use this and it allows lower ISO and works great. Hard to beat the sharpness and quality of the primes. Great photos by the way


Chris
01-20-2015, 11:30 AM   #58
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Mount your Nikon lenses on Pentax K

If you are considering going from Nikon to Pentax. know that all Nikon lenses can mount on Pentax using adapters. Might make your move less heart-rending.

There are two kinds of lens adapters: without glass (macro only) and with glass. Cost is $15-30. The macro ones don't affect the optical quality, but do prevent infinity focus. The ones with glass act as a 1.4x teleconverter, and keep infinity focus. It's cheap glass, so there is some impact on image quality that is acceptable to most people, not all. You can use all your Nikon glass, but the G lenses which lack aperture rings would be wide open. I have both macro and glassed Nikon lens adapters for Pentax K, and yep, they work well.

I also have them for MD, FD, and Konica AR, but that's another story. It's a neat trick to use the orphan lenses on a modern body.

There is also a really clever product called MultiMount that I don't see people using much, but it is very very interesting. Instead of a lens adapter, it is a replacement camera lens mount. You swap it onto your Pentax camera body and suddenly you can mount and use Nikon and Olympus lenses, with no lens modifications (need a thin shim for Nikons). You can also mount pentax, of course, with no changes. You can also mount Konica lenses but they focus macro only. You can possibly mount Y/C lenses with mods, to remove protruding stuff. This is all possible because the lens register distances for Nikon and Olympus (46.5mm and 46mm) are very slightly longer than for Pentax (45.5mm), so you keep infinity focus. Actually they focus a little beyond infinity, and the minimum focus distance is a tad longer.

This costs' $100 for non WR version, 117 for WR version. See it here:
Pentax K+ Multi-Mount (WR version) - Adaptist

I want one but I have not gotten around to ordering. I'm a little cautious about playing with my camera. I can hack lenses all day, but I don't want to break my old friend.
03-13-2015, 05:31 PM   #59
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QuoteOriginally posted by slowhands95128 Quote
If you are considering going from Nikon to Pentax. know that all Nikon lenses can mount on Pentax using adapters. Might make your move less heart-rending.

There are two kinds of lens adapters: without glass (macro only) and with glass. Cost is $15-30. The macro ones don't affect the optical quality, but do prevent infinity focus. The ones with glass act as a 1.4x teleconverter, and keep infinity focus. It's cheap glass, so there is some impact on image quality that is acceptable to most people, not all. You can use all your Nikon glass, but the G lenses which lack aperture rings would be wide open. I have both macro and glassed Nikon lens adapters for Pentax K, and yep, they work well.

I also have them for MD, FD, and Konica AR, but that's another story. It's a neat trick to use the orphan lenses on a modern body.

There is also a really clever product called MultiMount that I don't see people using much, but it is very very interesting. Instead of a lens adapter, it is a replacement camera lens mount. You swap it onto your Pentax camera body and suddenly you can mount and use Nikon and Olympus lenses, with no lens modifications (need a thin shim for Nikons). You can also mount pentax, of course, with no changes. You can also mount Konica lenses but they focus macro only. You can possibly mount Y/C lenses with mods, to remove protruding stuff. This is all possible because the lens register distances for Nikon and Olympus (46.5mm and 46mm) are very slightly longer than for Pentax (45.5mm), so you keep infinity focus. Actually they focus a little beyond infinity, and the minimum focus distance is a tad longer.

This costs' $100 for non WR version, 117 for WR version. See it here:
Pentax K+ Multi-Mount (WR version) - Adaptist

I want one but I have not gotten around to ordering. I'm a little cautious about playing with my camera. I can hack lenses all day, but I don't want to break my old friend.
To me as an astro-landscape shooter, that crop factor would be a show-stopper, indeed.

But honestly, I'm more sad that Tokina doesn't make a Pentax Mount 11-16, than I am sad about any Nikon lens. Go figure!

Besides, if I ever switch to Pentax, one of the biggest reasons would be for the weather-sealed-ness of the entire system, not just the bodies, and so I'd much rather give up on adapters or Tokina / Sigma lenses, and just root for Pentax making a couple good weather-sealed ultra-wides that can hit f/2.8 or faster...

Especially if they make a full-frame camera soon; I could really go for a Rokinon 14mm 2.8 (if no other option) on that, plus a Rokinon 16mm f/2 (which I owned once before and sold, here) on a K-3...

=Matt=
03-13-2015, 06:17 PM   #60
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QuoteOriginally posted by Matthew Saville Quote

Andromeda and the winter Milky Way, over Rhyolite:
That is awesome.
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