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09-20-2010, 07:33 AM   #1
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New DA 18-135mm a step backwards?

I was just reading the new DA 18-135 lens announcement. Two things stood out for me (from the len's slick sheet):
  • 3. Extra-smooth SDM autofocus operation
    A DC motor built into the lens’ AF (autofocus) unit assures extra-smooth autofocus operation.* Since it features a rotation-free mechanism to keep the focus ring stationary during autofocus operation, the user can hold the lens in exactly the same way as when using this lens in the manual-focus mode.
    * This lens is compatible with the PENTAX K-5, K-r, K-7, K-x, K-m, K20D, K200D, K100D Super and K10D (with Ver. 1.30 or later firmware installed) camera bodies. When mounted on other camera bodies, the focus mode is automatically switched to manual.
  • 2. Simplified weather-resistant construction
    This zoom lens features a simplified weather-resistant construction to prevent the intrusion of water and moisture. By mounting it on a weather-resistant PENTAX digital SLR camera body, the user is assured of a durable, dependable digital imaging system that performs superbly, even in the rain and mist, as well as at locations prone to the spray of water.

So they 1) removed the screwdrive from the lens and its SDM only so that on a non SDM capable body (K100 and before) its a manual lens and 2) they removed the focus distance scale.

Is it only me that this appears to be somewhat a step backwards. The new 35/2.8 looses the focus distance also, and in that its suppose to be a budget lens, I do not remember seeing any indication of an SDM motor. The lack of screwdrive does seem to be a trend, now. The new bodies still support old screwdrive lenses, which is still a plus.

09-20-2010, 07:37 AM   #2
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Some of the last few SDM lenses Pentax put out are SDM only. I know the DA 17-70/4 is SDM only and doesn't have a screwdrive. On older DSLR bodies it can only be used in MF. I believe the DA*55 is SDM only as well, although I never owned that one so I'm not 100% sure.
09-20-2010, 07:47 AM   #3
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First of all, it's not out yet. Let's keep calm )

SDM lenses are not a technical step backward, even though some might say they prefer screw-drive. If this was any other brand, AF mode would not even be mentioned, but since this is Pentax and the company supports older models and technologies, they prefer to play fair. That's all.

Simplified might mean simply that they're getting better. They did not write "less reliable"...

this lens's MSPR is quite high, but it looks like an excellent package. and another proof that Pentax are dedicated to providing WR to their customers.
09-20-2010, 07:50 AM   #4
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It's a KAF3 lens, so this behavior is to be expected.

They're talking about a new DC motor- maybe it'll actually be fast? (esp. considering the pricetag)

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09-20-2010, 07:53 AM   #5
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I don't see any step backward compare to other lower-ended DA zooms

DA 18-55mm WR (shorter ranger and focusing ring rotate)
DA 17-70mm (no WR shorter ranger and focusing ring rotate)
DA 18-250mm (No WR and focusing ring rotate)
09-20-2010, 08:07 AM   #6
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QuoteOriginally posted by bdery Quote
this lens's MSPR is quite high, but it looks like an excellent package. and another proof that Pentax are dedicated to providing WR to their customers.
Agreed. I'll wait for further tests, but so far it looks like I'll order one with my K-5 when I decide to replace my K-7.
09-20-2010, 08:23 AM   #7
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Leaving legacy equipment behind so that you can embrace new, better technology, in any other sector, is called "moving forward" not taking a step backwards. Remember the floppy drive?
09-20-2010, 08:25 AM   #8
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What is the MSRP?

09-20-2010, 08:29 AM   #9
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SDM only will make a lot of people leery of this lens, myself included.
09-20-2010, 08:30 AM   #10
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Actually, the thing that stands out most to me is they're not calling the focusing system SDM. Many of us know SDM was not reliable at all, so maybe the DC is Pentax's new upgraded in-lens focusing system that doesn't break? Many people asked Pentax to release an SDM II with the problems fixed, so maybe this is it as it seems they took customers' suggestions to design the recent releases.
09-20-2010, 08:58 AM   #11
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QuoteOriginally posted by interested_observer Quote
So they 1) removed the screwdrive from the lens and its SDM only so that on a non SDM capable body (K100 and before) its a manual lens and 2) they removed the focus distance scale.
"Removed"? Which previous 18-135 lens had those features? Answer: there were no previous 18-135's for this to be "removed" from. They started with a clean slate and decided which features needed to be there. "Didn't add" is the more appropriate term here.

Anyhow, I think the handwriting's been on the wall regarding screw drive for quite some time now; doesn't seem surprising to me that they are going the way of everyone else and offering more and more SDM-only lenses.

As for the focus distance scale - I guess that's useful to maybe 5% of the population 5% of the time, but I can't see most really losing sleep over this.
09-20-2010, 09:38 AM   #12
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The focus distance scale isn't that big of a deal to me. If it would have been like the 55 1.4's scale, it's nearly worthless.

What is the lens' MSRP? I can't find it anywhere.
09-20-2010, 09:45 AM   #13
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I'm excited about it myself. I've wanted an SDM lens for the quiet operation and if it's a more reliable system then even better. And what is the difference of having an SDM lens with our without Screw drive on a SDM capable body? And I expect that by being 'only' a 18-135 the optical quality would be better than many of the 10xish super zooms out there. I'm going to wait and see but it looks pretty good to me..
09-20-2010, 09:51 AM   #14
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If I understand well, this is not a SDM lens (no sonic drive motor) but a lens using a new kind of magnetic motors.
09-20-2010, 12:15 PM   #15

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im very interested in this new lens personally. I have not really been interested in the DA series, well basically never. but now im taking a second look with this new 18-135, the new 35 and the 55 which I have wanted ever since i rented one for an event. everyone is bashing pentax left and right for not giving them what they want, but believe it or not what pentax is offering is really appealing to a lot of people.

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