[tram57]

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Anyone been able to confirm whether any 1.4x or 1.5x exists that will AF with Pentax DA* SDM lenses or Sigma HSM lenes. Have a K7; interested in the sigma 70-200 f/2.8 EX DG HSM and would like a TC that preserves AF functionality.

[davidreilly3207]

My DA*50-135mm Pentax works well with my Tamron 1.4x AF-PZ MC4 on my K20d body. The PZ stands for power zoom and those are the contacts used for SDM.

[imtheguy]

Anyone been able to confirm whether any 1.4x or 1.5x exists that will AF with Pentax DA* SDM lenses or Sigma HSM lenes. Have a K7; interested in the sigma 70-200 f/2.8 EX DG HSM and would like a TC that preserves AF functionality.

Welcome to the Forum.

There are a lot of threads recently on your question. You might get a lot more info if you use the Forum search tool and find a few.

[tram57]

spent quite a bit of time searching, and reading about the TC's - does a particular thread come to mind that clearly addresses this question? Tx.

[deadwolfbones]

afaik the only TC that will work with Sigma HSM lenses is the Kenko 1.5x SHQ, which is quite rare.

[pop4]

I have a Kenko Pz-AF 1.5x Teleplus SHQ TC that works fine with my Sigma 70-200mm f/2.8 HSM II lens. And since it works with Sigma HSM, I see no reason why it shouldn't work with SDM.

[tram57]

Interesting. The user reviews on the B&H site state that the Kenko1.5x DF AF TC does not autofocus with the pentax DA* SDM lenes. Is the Kenko TC you are referring to as working with the Sigma lens a different model, or the same?

[deadwolfbones]

The one you're looking for is the one pictured here: Kenko 1.5X Pz-AF Teleplus SHQ teleconverter for Pentax - eBay. (end time 30-Jan-10 00:04:14 AEDST)

Which as far as I can tell is not the same one on the B&H site.

[pop4]

Interesting. The user reviews on the B&H site state that the Kenko1.5x DF AF TC does not autofocus with the pentax DA* SDM lenes. Is the Kenko TC you are referring to as working with the Sigma lens a different model, or the same?

They are two different teleconverters.

The one on BH is a Kenko 1.5x DF AF Teleconverter, which I believe doesn't support HSM/SDM. The markings on this TC are: 1.5X TELEPLUS MC

The one I have is a Kenko 1.5x Pz-AF SHQ Teleconverter, which I KNOW for sure supports HSM. The markings on this TC are Pz-AF 1.5X TELEPLUS SHQ

Hope that clears things up.

[tram57]

Thanks! Very informative.

[danielchtong]

Thanks! Very informative.

I have compiled from this and other forums what experienced users know. Updated late 2009. Pl note that there is still no current TC that works with any SDM lenses . Two TCs are known to work with SDM and they are not current model. That means you have to buy them used or from ebay


+++++++++++++++++++++++++++++++++++++++++++++++

Tamron 1.4x Pz-AF MC4 AF works. SDM no re Brad (photo.net)

Tamron-F Pz-AF MC4 1.4x both SDM & AF works for DA*300mm re Dave (photo.net)


Tamron-F Pz-AF MC4 1.4x both SDM 7 AF works for DA*60-250mm as per dick eduard of dpreview

Tamron-F Pz-AF MC4 1.4x *I had with the lens is its compatibility with the Tamron SP 1.4x TC Sigma* 70-200mmHSM F2.8

HSM works fine at 70mm, but absolutely will not lock focus at or anywhere around 200mm, and I tested it in*full sun*- very high contrast conditions. Hunts back and forth,****
Ash of Pentaxforums said 090904


Tamron-F Pz-AF MC4 1.4x both SDM & AF works for DA*300mm as per Toshi, moderator of Pentaxforums.com.

Tamron-F Pz-AF MC4 1.4x both SDM & AF works only 10% of the time for DA* 50-135mm but hunts a lot re Miserere

Tamron-F Pz-AF MC4 1.4x with the Sigma 70-200mm -new with HSM . The HSM AF works. It really didn't work all that well indoors at night according to Dave Hollander of Photo.net

Kenko DG Pz-AF 1.5x TELEPLUS MC no AF no SDM on DA*300mm re Dave (photo.net)

Kenko DG Pz-AF 1.5x TELEPLUS MC AF works on older AF lens re Dave (photo.net)

Kenko Pz-AF 1.5X TELEPLUS MC only AF works; SDM no as per jgredline of Pentaxforums.com

Kenko Pz-AF 1.5x TELEPLUS SHQ both AF & SDM works for DA*200mm and all older AF lens re Daniel

Kenko Pz-AF 1.5x TELEPLUS SHQ both AF & SDM works for DA*300mm re Borno (Tom) of Pentaxforums.com ….SDM hunts a bit with DA*300mm

Kenko Pz-AF 1.5x TELEPLUS SHQ both AF & SDM works for DA*50-135mm but it does hunt quite a bit and often fails to lock focus according to heliphoto of Pentaxforums ; Buddha Jones of Pentaxforums not happy with its result ;

**************************************************

Daniel, Toronto

[danielchtong]

They are two different teleconverters.

The one on BH is a Kenko 1.5x DF AF Teleconverter, which I believe doesn't support HSM/SDM. The markings on this TC are: 1.5X TELEPLUS MC

The one I have is a Kenko 1.5x Pz-AF SHQ Teleconverter, which I KNOW for sure supports HSM. The markings on this TC are Pz-AF 1.5X TELEPLUS SHQ

Hope that clears things up.

Statement confirmed


Daniel

[NeverSatisfied]

I have compiled from this and other forums what experienced users know. Updated late 2009. Pl note that there is still no current TC that works with any SDM lenses . Two TCs are known to work with SDM and they are not current model. That means you have to buy them used or from ebay


+++++++++++++++++++++++++++++++++++++++++++++++

Tamron 1.4x Pz-AF MC4 AF works. SDM no re Brad (photo.net)

Tamron-F Pz-AF MC4 1.4x both SDM & AF works for DA*300mm re Dave (photo.net)


Tamron-F Pz-AF MC4 1.4x both SDM 7 AF works for DA*60-250mm as per dick eduard of dpreview

Tamron-F Pz-AF MC4 1.4x *I had with the lens is its compatibility with the Tamron SP 1.4x TC Sigma* 70-200mmHSM F2.8

HSM works fine at 70mm, but absolutely will not lock focus at or anywhere around 200mm, and I tested it in*full sun*- very high contrast conditions. Hunts back and forth,****
Ash of Pentaxforums said 090904


Tamron-F Pz-AF MC4 1.4x both SDM & AF works for DA*300mm as per Toshi, moderator of Pentaxforums.com.

Tamron-F Pz-AF MC4 1.4x both SDM & AF works only 10% of the time for DA* 50-135mm but hunts a lot re Miserere

Tamron-F Pz-AF MC4 1.4x with the Sigma 70-200mm -new with HSM . The HSM AF works. It really didn't work all that well indoors at night according to Dave Hollander of Photo.net

Kenko DG Pz-AF 1.5x TELEPLUS MC no AF no SDM on DA*300mm re Dave (photo.net)

Kenko DG Pz-AF 1.5x TELEPLUS MC AF works on older AF lens re Dave (photo.net)

Kenko Pz-AF 1.5X TELEPLUS MC only AF works; SDM no as per jgredline of Pentaxforums.com

Kenko Pz-AF 1.5x TELEPLUS SHQ both AF & SDM works for DA*200mm and all older AF lens re Daniel

Kenko Pz-AF 1.5x TELEPLUS SHQ both AF & SDM works for DA*300mm re Borno (Tom) of Pentaxforums.com ….SDM hunts a bit with DA*300mm

Kenko Pz-AF 1.5x TELEPLUS SHQ both AF & SDM works for DA*50-135mm but it does hunt quite a bit and often fails to lock focus according to heliphoto of Pentaxforums ; Buddha Jones of Pentaxforums not happy with its result ;

**************************************************

Daniel, Toronto

To add to this tally:
I tried a Kenko 1.5 from B&H a while back, don't remember which version now (sorry), but it didn't work AT ALL for any of my SDM lenses.

I have the Tamron 1.4 which works VERY poorly on the DA*50-135, hardly ever locks focus unless it's bright light and contrasty, hunts a lot. HOWEVER, this same TC works much better on my DA*300, go figure! (And it works quite well on my Tamron 70-200/2.8 but of course that is not an SDM or HSM lens.)

[pop4]

Kenko Pz-AF 1.5x TELEPLUS SHQ both AF & SDM works for Sigma 70-200mm F2.8 HSM II re pop4 of PentaxForums.com

[danielchtong]

To add to this tally:
I tried a Kenko 1.5 from B&H a while back, don't remember which version now (sorry), but it didn't work AT ALL for any of my SDM lenses.

I mentioned that SDM compatible ones are no longer in production. If you can order from B&H new, it is not going to work.

I have the Tamron 1.4 which works VERY poorly on the DA*50-135, hardly ever locks focus unless it's bright light and contrasty, hunts a lot. HOWEVER, this same TC works much better on my DA*300, go figure! (And it works quite well on my Tamron 70-200/2.8 but of course that is not an SDM or HSM lens.)

Sounds reasonable .
TC works best with fast & prime lens. It sucks usually with slow lens or zoom as the latter has more optical elements resulting in more interior refraction and distortion of course.
Also all these TC are not custom-made for your lens. So mileage does vary.



Daniel