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04-19-2016, 06:31 AM   #1096
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To date, DC has been the only alternative developped by RI to Super Doomed Motors ... that are still included in recent 645 lenses.


Only K-mount FF Tamron rebadges get some new "SDM" engine, but not that from Ricoh, nor faster than DC engines.


Last edited by Zygonyx; 04-19-2016 at 06:39 AM.
04-19-2016, 06:41 AM   #1097
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QuoteOriginally posted by falconeye Quote
Like ring-type
asahi-man said a while ago that it was ring-type.
But I have never seen a diagram.

The DFA 70-200 lens engineers (Makoto Iikawa and Masakazu Saori) talk about the 70-200 design process here in one of the early 'Pentax Story' app presentations (see the section under 'Engineers Interview'):

If anyone can read Japanese, it would be great if they could let us know if the Pentax engineers provide any information about the lens motor.
04-19-2016, 08:15 AM   #1098
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QuoteOriginally posted by rawr Quote
asahi-man said a while ago that it was ring-type.
But I have never seen a diagram.

The DFA 70-200 lens engineers (Makoto Iikawa and Masakazu Saori) talk about the 70-200 design process here in one of the early 'Pentax Story' app presentations
Thanks for the link, interesting resource (although I can't read the Japanese).

I think the DC motor is confirmed by the fact that it is in the lens' name and also the official specs. AFAIK, ring-type motors are all ultrasonic (piezo), so this would be off the table. There are non-ring type ultrasonic motors (like Pentax SWM) which a DC motor could outperform though.

A DC motor would have to have sufficient size and a proper gear box to be powerful enough to compete with ring-type motors. That's why I asked if we know anything about the motor, spec-wise.
04-19-2016, 12:56 PM - 1 Like   #1099
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Anyone just needs to google "brushless ring motor" or "brushless DC motor" to find ring type DC motors with enough torque to drive vehicles.
For samples:
http://www.thingap.com/wp-content/uploads/2013/05/ThinGap-advanced-brushless-motors.jpg
https://www.aerotech.com/product-catalog/motors/rotary-motors/s-series.aspx
Products | ThinGap high power density brushless motors

04-19-2016, 01:13 PM - 1 Like   #1100
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QuoteOriginally posted by beholder3 Quote
Anyone just needs to google "brushless ring motor" or "brushless DC motor" to find ring type DC motors with enough torque to drive vehicles.
For samples:
http://www.thingap.com/wp-content/uploads/2013/05/ThinGap-advanced-brushless-motors.jpg
https://www.aerotech.com/product-catalog/motors/rotary-motors/s-series.aspx
Products | ThinGap high power density brushless motors
asahi man showed a photo of exactly this type (Aerotech) of brushless DC gearless torque motor in an argumentative post about Pentax DC focus motor patents.

Post

Kollmorgen DC Torque Motor


Last edited by monochrome; 04-19-2016 at 01:24 PM.
04-19-2016, 01:25 PM   #1101
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A eagerly wait to have my new and definite try with K-1 and that bloody zoom-lens.
04-19-2016, 04:19 PM   #1102
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QuoteOriginally posted by rawr Quote
If anyone can read Japanese,
No need
There is an English web version of the '70-200 Pentax story' on the web page for the lens on RI Japan, including the 'Engineers Interview'.

HD PENTAX-D FA★ 70-200mmF2.8ED DC AW | RICOH IMAGING

Lots of text about lens ergonomics, coatings, AW etc throughout the whole site. No mention at all of AF motor, AF speed.
04-19-2016, 04:51 PM   #1103
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Just checked my order at B&H and the website is now saying: "Expected availability: Beginning of May 2016" Not sure if that is really a change or just reality since they will be closed for the Passover holiday until May 2nd.

Leaving on a coast trip on 5 May so this is really getting too close..........

---------- Post added 04-19-16 at 04:53 PM ----------

Amazon says "item will be released on April 25th". Anyone think I should cancel the B&H order and order from Amazon?

---------- Post added 04-19-16 at 04:56 PM ----------

Adorama now says: "Manufacturer will start shipping this item on 05/15/2016"

04-19-2016, 04:59 PM   #1104
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QuoteOriginally posted by jatrax Quote
Just checked my order at B&H and the website is now saying: "Expected availability: Beginning of May 2016" Not sure if that is really a change or just reality since they will be closed for the Passover holiday until May 2nd.
I don't suppose we would get lucky and the listed availability is for new orders going forward?
04-19-2016, 05:05 PM   #1105
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QuoteOriginally posted by jlstrawman Quote
I don't suppose we would get lucky and the listed availability is for new orders going forward?
Doubtful. But I don't think it matters because they are closed April 21 through May 1st. They state no shipping or ordering during that period. Not sure if that means no receiving as well but probably does. So even if RIcoh delivers on the 25th there will be no one there to receive the order.
So unless they ship tomorrow I do not see how they will ship before May 4 or 5........ or later..............
04-19-2016, 05:09 PM   #1106
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QuoteOriginally posted by jatrax Quote
Just checked my order at B&H and the website is now saying: "Expected availability: Beginning of May 2016" Not sure if that is really a change or just reality since they will be closed for the Passover holiday until May 2nd.

Leaving on a coast trip on 5 May so this is really getting too close..........



Amazon says "item will be released on April 25th". Anyone think I should cancel the B&H order and order from Amazon?[COLOR="Silver"]
Given the information you have and your impending trip, I might consider changing the order if I was you.
04-19-2016, 05:18 PM   #1107
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QuoteOriginally posted by jatrax Quote
Doubtful. But I don't think it matters because they are closed April 21 through May 1st. They state no shipping or ordering during that period. Not sure if that means no receiving as well but probably does. So even if RIcoh delivers on the 25th there will be no one there to receive the order.
So unless they ship tomorrow I do not see how they will ship before May 4 or 5........ or later..............
They probably have limited operations not related to 'working', or in their terms 'producing'. That means the website is up, but the Shopping Cart is closed. The phone answers - but goes to VM.

The warehouse is probably open for receiving - there would be hundreds of thousands of merchandise piling up if it wasn't - and it might even be processed in the inventory receiving system. But they won't be shipping because that generates billing and billing is 'production'.

As I wrote above, my ship date is May 2, and I just ordered a couple days ago. I guess that either means they didn't sell out their initial order yet or they added to their initial order in response to demand.
04-19-2016, 05:24 PM   #1108
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QuoteOriginally posted by monochrome Quote
As I wrote above, my ship date is May 2, and I just ordered a couple days ago.
Missed that, I thought you were waiting for August?
04-19-2016, 05:56 PM   #1109
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QuoteOriginally posted by jatrax Quote
Missed that, I thought you were waiting for August?
In my sig you can see that I had a windfall. I was waiting for mrs. monochrome to authorize purchase and she was waiting for August (when my annual bonus is paid). We She decided the unexpected tax refund could serve as an advance on my bonus .
04-19-2016, 05:57 PM   #1110
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Ordering from Amazon at this late date is probably not an option since they probably already have their quota for the first shipment. In any case, there is about $180 in tax added.
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