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09-21-2010, 02:02 AM   #151
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QuoteOriginally posted by Steelski Quote
I think you need to read the patent. It talks about DC motor.
page 12!!!
Right, they talk about the problems with using DC motors. (Which this new patent are supposed to fix)

09-21-2010, 02:16 AM   #152
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We don't even know if the motor in the new lens has anything to do with the patent application, so we shouldn't jump to any conclusions until someone has opened one of 'em babies up.
09-21-2010, 03:56 AM   #153
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QuoteOriginally posted by Steelski Quote
I think you need to read the patent. It talks about DC motor.
page 12!!!
sorry didn't read, me just take pics, no good at tech talk
09-21-2010, 04:30 AM   #154
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QuoteOriginally posted by blende8 Quote
Perhaps Pentax wants to avoid the term SDM, because it carries very negative connotations in the Pentax community and rightly so.
I think they should have moved in the direction of S&M. Would at least make their marketing videos more interesting.

09-21-2010, 04:33 AM   #155
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QuoteOriginally posted by Gimbal Quote
That patent does not describe a Direct Current (DC)-motor. A direct current motor runs on direct current, the one described in the patent needs alternating phases or pulses to run.

A DC-motor is usually found in the cheapest of toys. So it's probably a new micromotor with a new name to differentiate it from the old ones. Nothing fancy at all.
If you read the full patent they talk about the fixed alternating multi-pole magnets and then controlled magnets required to step the lens to the next fixed point.

There are two types of electromagnets (well 3) the AC type which is either a DC-magnet with a built in AC-DC converter (obviously not this) and a then are laminated core AC-magnets, these produce an alternating magnetic field, and therefore would be useless for this patent.

There are two types of DC-electromagnets. One is useless to the patent, but a bi-polar magnet, flips poles when a DC current is applied. This is the type they are talking about.

So they may in-fact be using DC to identify the described technology. Though it is doubtful, as even the patent describes a "DC-motor" aka. current micromotor.
09-21-2010, 04:34 AM   #156
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Will Pentax remake silently SDM lenses to DC lenses?
09-21-2010, 04:36 AM   #157
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I don't think it can happen silently in a sense that letters DC will have to appear on new lenses designation...
09-21-2010, 04:44 AM   #158
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Is this lens going to be ready to ship in October with the K-5?

09-21-2010, 04:54 AM   #159
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QuoteOriginally posted by K-9 Quote
Is this lens going to be ready to ship in October with the K-5?
As kit lens in November.
09-21-2010, 05:54 AM   #160
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QuoteOriginally posted by ogl Quote
As kit lens in November.
aha, the first delay, now we're talking
09-21-2010, 06:42 AM   #161
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QuoteOriginally posted by Asahiflex Quote
It's the small ring near the mount.
Not that. Different. You look your lens.
09-23-2010, 02:10 PM   #162
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I really LIKE the idea of this lense...I am hoping it is positioned and priced similar to the Canon EF-S 55-250IS which was basically a test lense for their, at the time, new 4-stop IS. It's an micro-motor AF lense with a plastic build but at $250 street it's maybe the best value lense knock-around lense in the whole Canon line-up for both the one-lense people as well as for a casual tele-zoom. The real bonus is it's a pretty darned sharp lense...took some super shots with mine.

I like what I read about this new 18-135 because of the range, the WR and the new motor. Am I correct in understanding that the AF works w/o turning the focus ring? If so, that makes me wonder if the point of failure on SDM was/is the torque caused when holding the AF ring when trying to AF resulting in strain on the mechanics in the SDM? How weird would it be that the next evolution of SDM showed where the real POF in SDM exists. If that is the POF then knowing would let people be more cautious and mindful of where they hold their SDM lenses. Of course that would not explain the SDM lenses which failed out of the box or within days of first use like my 50-135 did.

I really hope the pricing of this lense is in the budget area of under $300 because while it has WR as well as the new AF system, it's a work in progress and we customers are, in effect, the beta test group. In exchange for buying into it early we get a nice deal on the lense and HoyaTax gets a lot of users willing to take a shot and really put it through it's paces.

BTW, something else comes to mind about if the whole AF ring torque is the POF it makes sense that HoyaTax would not reveal it to prevent people from intentionally foobar'ing their SDM lense near the end of the warranty period. I could see this also as a cumulative issue as well, that over time the mechanism just gets weaker and weaker even from accidental holding of the AF ring while it moves during AF no matter how brief that the movement was restricted. But I honestly do not remember if the focus ring on my 50-135 moved during AF or not?

But if this beastie is some sort of $300+ lense I won't be buying it anytime soon...
09-23-2010, 02:40 PM   #163
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it looks like that the "new dc" is only a simple micromotor like in the tamron lenses
nothing special
09-23-2010, 02:44 PM   #164
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zack:

I honestly would be OK with a micro-motor if the lense is priced accordingly and is reasonably quiet. It could be a case where Pentax is trying some new gearing that would then be added to their next SDM solution...I mean if it really is a micro-motor, I dunno because I haven't read the whole thread just yet.
09-24-2010, 07:46 PM   #165
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7.5:1 Zoom ratio = they can keep it.

I like to think of "do everything" zooms the same way I think of "Asian Fusion" restaurants - they try to "do everything" and end up doing it all poorly. Zooms beyond a 3:1 ratio introduce too many optical compromises to be good performers, so only those too lazy to carry a few lenses to cover the same range, and who don't give a crap about their image quality, should buy them. I don't like mediocre food, and don't like mediocre lenses, either.
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