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03-29-2015, 07:23 AM   #346
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A little longer to drive the lens focusing group - wouldn't that help with manual focus, i.e. directly translate into a longer focus ring travel?

03-29-2015, 07:27 AM   #347
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QuoteOriginally posted by Reptilezz Quote
You mean the canon 100-400 USM II? Nah that thing is incredibly fast, I watched a video of it just after the Pentax and the canon focused at infinity to close and out agin in the same time the Pentax did 2/3 of the process mention of the canon lens.
Cool,it means itīs also very very fast
Best regards
03-29-2015, 07:40 AM   #348
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asahi man and kenspo - nice to have both posting alongside each other here
Keep up the good work!
03-29-2015, 07:49 AM   #349
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And keep up the money....will get the new zooms for my action tour and than i kill the AF ;-)
Will see wich one i buy than.
Think both :-)
Best regards ;-)

03-29-2015, 08:50 AM   #350
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QuoteOriginally posted by Kunzite Quote
"AF speed is really fast!" - you say; is it on the same level as the 70-200? Or "just" better than other Pentax lenses, but below the 70-200?
Could you please compare those lenses a bit - for people trying to decide e.g. between faster aperture (incl. with the 1.4xRC) and reach? Thank you.
It is the same technology on both lenses, ie instead of having a small sdm engine with a reduction gear - low torque at the output of the engine, so the reduction gear is needed to increase torque but reduces speed -, it is the new DC ring engine patented by Pentax. It is located at the bottom of the lens, so the unusual shape of these 2 new zooms with a large diameter bottom. It drives the focusing ring directly with a high torque engine, no reduction so very fast.
I think I have already posted it, but there you are, the new engine is circled in red
03-29-2015, 09:27 AM   #351
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Thanks, indeed you posted that image before
I didn't want to assume anything, even if the two lenses are using the same or a similar AF mechanism. But Kenneth said he couldn't see a difference, and I expect the same to be confirmed by other users/testers.

If that's indeed the AF motor (is it confirmed? I'm not aware of the source), it likely means they implemented the "ring-type DC" patent we saw a while ago. Anyway, what matters is that it's fast.
03-29-2015, 09:46 AM   #352
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Has anyone seen a cut-away of the DA 16-85? Curious if it uses the same type of ring motor or if the APS-C lenses are using something else. I notice the focusing ring on both the 16-185 and the new DFA lenses is now on the bottom, coincidence?
03-30-2015, 02:32 AM   #353
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QuoteOriginally posted by asahi man Quote
No,the SDM also needs a gear.
The new DC Drive is the patent 3 years ago.
Motordrive withoutgear,direct power on the tube with the focusgroup
Like the USM Ring.
I compared it with the Nikon 2,8 70-200 II,comparable speed,but with a little bit longer focusway.
So it needs a little longer to drive from endless to close and back to endless.
But,if anybody can not catch the motive with the new lenses and the K-3.......should buy a cellphone for making pictures

Best regards

p.s.: actually both lenses are on stock may/June.
Hi Asahi man,

About this three year old DC motor patent: are the DC motors in the latest APSC lenses also based on this patent?

Regards
Chris

03-30-2015, 06:44 AM   #354
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QuoteOriginally posted by goubejp Quote
It is the same technology on both lenses, ie instead of having a small sdm engine with a reduction gear - low torque at the output of the engine, so the reduction gear is needed to increase torque but reduces speed -, it is the new DC ring engine patented by Pentax. It is located at the bottom of the lens, so the unusual shape of these 2 new zooms with a large diameter bottom. It drives the focusing ring directly with a high torque engine, no reduction so very fast.
I think I have already posted it, but there you are, the new engine is circled in red
That does not look like it could be a ring motor. There are no obvious stator or rotor ring connections to movable sections of the body. The parts also look plastic, if it was a induction type ring motor as per the patents you would expect to see some coil windings/magnets/metal parts. Also they would make a big deal out of this is they had a brand new fast motor - instead they say nothing. As such I suspect these lenses just use a normal DC motor just like the other DC lenses, with the only difference being that that the motor is probably larger. There also appears be an encoder/guide shaft fr the focus group which is new. I think this is for better contrast focus control.
What you circled there is probably just a plastic spacer ring used for mounting the PCB board that can be seen in the images.

So this is 90% likely that this uses just a normal DC micor-motor. If someone want to take the lens mount off one of these and looks around it would be great to be proven wrong, but it is unlikely.
03-30-2015, 07:03 AM - 1 Like   #355
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QuoteOriginally posted by Ayoh Quote
That does not look like it could be a ring motor. There are no obvious stator or rotor ring connections to movable sections of the body. The parts also look plastic, if it was a induction type ring motor as per the patents you would expect to see some coil windings/magnets/metal parts. Also they would make a big deal out of this is they had a brand new fast motor - instead they say nothing. As such I suspect these lenses just use a normal DC motor just like the other DC lenses, with the only difference being that that the motor is probably larger. There also appears be an encoder/guide shaft fr the focus group which is new. I think this is for better contrast focus control.
What you circled there is probably just a plastic spacer ring used for mounting the PCB board that can be seen in the images.

So this is 90% likely that this uses just a normal DC micor-motor. If someone want to take the lens mount off one of these and looks around it would be great to be proven wrong, but it is unlikely.
Quoting asahi man from earlier:

But,what means DC motor?
Nothing.
The motor in the kit lenses are small and only to use in light weight lens systems with short movement.
But there are lots of different types of DC motor.
The ring drive in the Pentax patent was NOT a ultrasonic like canons old type since the 90.
Old school,Nikon is using different types.
Here is a DC drive,looks more like the Pentax patent.

Direct Drive DC Torque Motors | Kollmorgen | Brush DC Electric Motors

Is that a ring motor, a DC motor or something else?

Read more at: https://www.pentaxforums.com/forums/16-pentax-news-rumors/287834-hd-pentax-d-...ml#post3142978

Last edited by monochrome; 03-30-2015 at 08:16 AM.
03-30-2015, 07:12 AM   #356
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QuoteOriginally posted by monochrome Quote
Read more at: HD PENTAX-D FA 150-450mm F4.5-5.6ED DC AW
nice, a link to the same tread
03-30-2015, 07:48 AM   #357
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That just reads as speculation based on a Patent, who knows it that was ever implemented. Looking at the patent embodiment it looks quite complex to make and probably expensive so it may not have made it t production. I cannot see anything that look like a induction ring motor in that lens cross-section and there is no mention of this type of new motor in any of the pentax marketing material. I remain sceptical until we see some actual evidence that such a motor is used. A well designed micro-motor system could do the job though, so its not necessarily all bad that there is no ring motor.

QuoteOriginally posted by monochrome Quote
Quoting asahi man

But,what means DC motor?
Nothing.
The motor in the kit lenses are small and only to use in light weight lens systems with short movement.
But there are lots of different types of DC motor.
The ring drive in the Pentax patent was NOT a ultrasonic like canons old type since the 90.
Old school,Nikon is using different types.
Here is a DC drive,looks more like the Pentax patent.

Direct Drive DC Torque Motors | Kollmorgen | Brush DC Electric Motors

Is that a ring motor, a DC motor or something else?

Read more at: https://www.pentaxforums.com/forums/16-pentax-news-rumors/287834-hd-pentax-d-...#ixzz3VsTM2SJN
03-30-2015, 08:02 AM   #358
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QuoteOriginally posted by Ayoh Quote
That just reads as speculation based on a Patent, who knows it that was ever implemented. Looking at the patent embodiment it looks quite complex to make and probably expensive so it may not have made it t production. I cannot see anything that look like a induction ring motor in that lens cross-section and there is no mention of this type of new motor in any of the pentax marketing material. I remain sceptical until we see some actual evidence that such a motor is used. A well designed micro-motor system could do the job though, so its not necessarily all bad that there is no ring motor.
asahi man is a pretty good source. One might say he knows what he writes about.

But Whatever.
03-30-2015, 08:02 AM - 1 Like   #359
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QuoteOriginally posted by Franc Quote
nice, a link to the same tread
as noted in post Dude needs to read the thread. Fixed link.

Last edited by monochrome; 03-30-2015 at 08:17 AM.
03-30-2015, 12:31 PM   #360
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QuoteOriginally posted by Ayoh Quote
That does not look like it could be a ring motor. There are no obvious stator or rotor ring connections to movable sections of the body. The parts also look plastic, if it was a induction type ring motor as per the patents you would expect to see some coil windings/magnets/metal parts. Also they would make a big deal out of this is they had a brand new fast motor - instead they say nothing. As such I suspect these lenses just use a normal DC motor just like the other DC lenses, with the only difference being that that the motor is probably larger. There also appears be an encoder/guide shaft fr the focus group which is new. I think this is for better contrast focus control.
What you circled there is probably just a plastic spacer ring used for mounting the PCB board that can be seen in the images.

So this is 90% likely that this uses just a normal DC micor-motor. If someone want to take the lens mount off one of these and looks around it would be great to be proven wrong, but it is unlikely.
You may see that the glass cut is also painted with dark paint, so you can't guess the material just by the aspect of the material.
A DC motor would be visible and there would be a gear mechanism visible.
Also see that the internal ring seems directly coupled with the focusing ring. A spacer ring would not touch the focusing ring
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