Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-19-2009, 04:37 PM   #1
Veteran Member




Join Date: Mar 2007
Location: Philippines
Posts: 1,399
Any news about the SDM TC?

Just thought that maybe someone here might have heard of a couple more details regarding this one. Basically, I'm interested to know if it has the same AF magic as the previous Pentax F 1.7x TC, in that it makes non-AF lenses, well, AF. Being a fairly new Pentax user, I kinda missed the boat when those were still available, and while there's one seller on eBay who has that, it's sitting at a price that's above my credit limit *sigh*.

If this new TC can do the same feat, then I'd rather just buy it locally when it comes out, where I can pay for it in straight cash. I'm not sure how long it'll take for my card company to raise my credit limit.

02-19-2009, 05:59 PM   #2
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
No

No news about anything. Be patient.
02-19-2009, 09:34 PM   #3
Veteran Member




Join Date: Jun 2008
Location: Guatemala
Posts: 338
From the pictures of it would seem the glass element doesn't really have enough space to move the distance required to focus. My guess is that it's just a teleconverter with SDM electrical contacts. It could also have a SDM micromotor in it to power screwdrive lenses, but that wouldn't make sense.
02-20-2009, 01:09 AM   #4
Pentaxian




Join Date: Sep 2006
Location: Antwerp, Belgium
Photos: Gallery
Posts: 1,008
It looks very much like the Tamron 1.4x does. So it will probably be similar in functionality. It certainly will not replace the F1.7x, that was a unique case.

I'm hoping it won't simply be a rebranded Tamron 1.4x. That one does have the powerzoom contacts and as such allows the camera to recognise an SDM lens and provide power to the lens to use its SDM system. However, even if the lens tries to focus, the camera never achieves focus lock with a SDM lens on a powerzoom enable TC. I suppose there's more than just powerzoom contacts to it, and I'm hoping they get that sorted out. I'm hoping the postponing of the DA*60-250/4 might be related to its being tuned to the TC and vice versa... I have found that the FA*300/4.5 still has enough light to focus with the 1.4x so the DA*60-250 being a f/4 shouldn't be a problem at all. A well matched 1.4x TC would make the DA*60-250/4 a very desirable lens, possibly even drawing back part of the crowd that got another telezoom after giving up on the long wait...

Wim

02-20-2009, 06:15 AM   #5
Veteran Member
palmor's Avatar

Join Date: Dec 2006
Location: North of Boston, MA
Posts: 798
QuoteOriginally posted by Ishpuini Quote
However, even if the lens tries to focus, the camera never achieves focus lock with a SDM lens on a powerzoom enable TC.

Wim
That probably shouldn't be a blanket statement. There are people out there shooting their DA* with both that Tamy 1.4x and the Kenko 1.5x TCs without any problems. What does seem strange is that some people (like you) are having issues with SDM and some of the same exact TCs that do work for other people. There is someone else here that has the same problem you mentioned with the same exact TC I have.

I have the Kenko 1.5x TC and it works flawlessly with the DA*300. So much that if this new Pentax TC isn't weather sealed I probably won't buy it.


John
02-20-2009, 06:44 AM   #6
Pentaxian
thibs's Avatar

Join Date: Jun 2007
Location: Belgium
Photos: Albums
Posts: 5,161
QuoteOriginally posted by palmor Quote
That probably shouldn't be a blanket statement. There are people out there shooting their DA* with both that Tamy 1.4x and the Kenko 1.5x TCs without any problems. What does seem strange is that some people (like you) are having issues with SDM and some of the same exact TCs that do work for other people. There is someone else here that has the same problem you mentioned with the same exact TC I have.

I have the Kenko 1.5x TC and it works flawlessly with the DA*300. So much that if this new Pentax TC isn't weather sealed I probably won't buy it.


John
AFAIK TCs with SDM contacts do not work well. TCs without SDM contacts do work fine.
02-20-2009, 07:52 AM   #7
Veteran Member




Join Date: Mar 2007
Location: Philippines
Posts: 1,399
Original Poster
Well, I'll just assume for now that it won't have the 1.7x magic, then. Thanks for the replies, guys. I hope there's more to it than just a plain-jane TC, though.
02-20-2009, 11:26 AM   #8
Pentaxian
thibs's Avatar

Join Date: Jun 2007
Location: Belgium
Photos: Albums
Posts: 5,161
QuoteOriginally posted by vinzer Quote
Well, I'll just assume for now that it won't have the 1.7x magic, then. Thanks for the replies, guys. I hope there's more to it than just a plain-jane TC, though.
Yes plain TC.
By the way, the 1.7x isn't called rear converter (Pentax usual terms for TCs) but AF adapter. The roadmap specificaly says "Rear converter".

02-20-2009, 12:37 PM   #9
Veteran Member
palmor's Avatar

Join Date: Dec 2006
Location: North of Boston, MA
Posts: 798
QuoteOriginally posted by thibs Quote
AFAIK TCs with SDM contacts do not work well. TCs without SDM contacts do work fine.
I have the Kenko with the SDM contacts (or power zoom contacts) and it works flawlessly with the SDM of my DA*300.
02-20-2009, 09:46 PM   #10
Pentaxian
philbaum's Avatar

Join Date: Oct 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659
QuoteOriginally posted by Ishpuini Quote
I'm hoping it won't simply be a rebranded Tamron 1.4x. That one does have the powerzoom contacts and as such allows the camera to recognise an SDM lens and provide power to the lens to use its SDM system. However, even if the lens tries to focus, the camera never achieves focus lock with a SDM lens on a powerzoom enable TC.
Wim
I get consistent focus locks with the Tamron 1.4x and the DA300 F4 lens. It does need a bit more light than just the DA300 lens alone, though :-)
02-21-2009, 05:27 AM   #11
Pentaxian
thibs's Avatar

Join Date: Jun 2007
Location: Belgium
Photos: Albums
Posts: 5,161
QuoteOriginally posted by palmor Quote
I have the Kenko with the SDM contacts (or power zoom contacts) and it works flawlessly with the SDM of my DA*300.
QuoteOriginally posted by philbaum Quote
I get consistent focus locks with the Tamron 1.4x and the DA300 F4 lens. It does need a bit more light than just the DA300 lens alone, though :-)
Very interesting. So there's something else at play then.
02-21-2009, 09:38 AM   #12
Pentaxian




Join Date: Sep 2006
Location: Antwerp, Belgium
Photos: Gallery
Posts: 1,008
QuoteOriginally posted by thibs Quote
Very interesting. So there's something else at play then.
Indeed... I tried a copy of the DA*55 on my TC and I had the same problem again... I wonder... could it be the TC, or is my "early production" K20D at fault? Although my K10D had the same problem... Probably my Tamron TC then... I think I'll try out the new TC before buying it when it becomes available just to make sure...

Wim
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
af, credit, limit, pentax, pentax news, pentax rumors, tc
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
645D, K-m2 and NEW LENSES DA*10-16/4 SDM, DA*20/2 SDM, DA*28/2 SDM ogl Pentax News and Rumors 165 08-11-2010 03:26 AM
NEWS, OVER 2000 viewers on News and Rumors Steelski Pentax News and Rumors 18 05-20-2009 07:08 AM
Does news from Samsung always mean it's news from Pentax? m8o Pentax News and Rumors 3 02-23-2009 04:33 PM
Flamewar/News not involving Pentax/Completely Unbased Speculation/Not News Forum nixcamic Site Suggestions and Help 8 12-18-2008 05:56 AM
New SDM rear TC, SDM only or SDM + screw drive? morfic Pentax SLR Lens Discussion 1 10-01-2008 08:23 AM



All times are GMT -7. The time now is 02:41 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top