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12-31-2009, 05:05 PM   #16
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It will of course focus to the minimum focus distance of the lens, I didn't mean to imply to the contrary. You must refocus manually as needed.

12-31-2009, 05:08 PM   #17
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QuoteOriginally posted by borno Quote
It will of course focus to the minimum focus distance of the lens, I didn't mean to imply to the contrary. You must refocus manually as needed.
So, for moving wildlife seems it's not a good converter or I'm wrong ?
12-31-2009, 05:09 PM   #18
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QuoteOriginally posted by netuser Quote
How does it work with sdm lenses ? It's like the 1.4 tamron ?
I'm not sure I understand your question. But I'll try.

I'm not sure how to describe this. As I understand it, it works by optically changing the register distanse. In other words, if the lens is out of focus, it compensates for this, within a limit. You need to "halfset" the lens. Then the TC does the rest of the job for you.

It works fine, except it does not report correct focal length to the camera. Usually focus is accurate, and much faster than most AF lenses.

Optically it is good for a TC, but I'm not a big fan, I often prefer to crop.
12-31-2009, 05:14 PM   #19
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QuoteOriginally posted by Fototim Quote
I'm not sure I understand your question. But I'll try.

I'm not sure how to describe this. As I understand it, it works by optically changing the register distanse. In other words, if the lens is out of focus, it compensates for this, within a limit. You need to "halfset" the lens. Then the TC does the rest of the job for you.

It works fine, except it does not report correct focal length to the camera. Usually focus is accurate, and much faster than most AF lenses.

.......
It seems I must get one for me .... depending on the lens I will get for birding... (just sold DA* 300/4)

12-31-2009, 06:00 PM   #20
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QuoteOriginally posted by netuser Quote
It seems I must get one for me .... depending on the lens I will get for birding... (just sold DA* 300/4)
Forgot two important pieces of information:

It i centre focus only. So it is not perfect for tracking targets that moves unpredictability.
And multi-segment metering does not work. IMO that's not very important, Since spot or centre metering works just fine in most situations when you shoot with a long tele combo.
12-31-2009, 07:28 PM   #21
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QuoteOriginally posted by koper Quote
if the teleconverter dose not work with SDM lenses,that means that he can not work with

Pentax smc P-DA 300mm F4 ED (IF) SDM or similar SDM lenses
most of the photographers have tamron TC
nobody is going to bay it
Wondering where you get this information from?
Please, give us some more details.
JP
12-31-2009, 07:33 PM   #22
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So, I assume this will work with SDM and non-SDM lenses, right?
I doubt Pentax would put out such product to work only with specific lenses.

Quoting Koper:
if the teleconverter dose not work with SDM lenses,that means that he can not work with

Pentax smc P-DA 300mm F4 ED (IF) SDM or similar SDM lenses
most of the photographers have tamron TC
nobody is going to bay it


My guess is that this TC will do the job with most Pentax lenses, SDM or not.
Any response to this?

JP
12-31-2009, 08:07 PM   #23
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one with the da300 and 1.7x afa



01-01-2010, 09:43 AM   #24
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Great pic borno. It seems that this tele-convertor can realy do the business in the right hands.
01-01-2010, 09:50 AM   #25
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With the Pentax F 1.7x AF converter, the AF of the lens will not move. You do prefocus manually on the lens, and the camera together with the moving lens in the converter will perform the fine focusing. It makes this with all lenses, no matter if the lens is MF, traditional AF or SDM AF.

A few shots of mine with this 1.7x TC:

on DA*300:






on Voigtlander 125/2.5:


Btw. I bought one of these new 1.7x TC as my old one started to show some weaknesses due to his age (and trips in very humid areas).

I contacted Pentax Germany and told them I found a brand new 1.7x af converter and due to the notice and the manual asked if Pentax is indeed producing it again. The answer is not telling if the TC is produced again, the answer just said that Pentax is not allowed to sell this TC in Europe due to ROHS regulations (Restriction of the use of certain hazardous substances).
01-01-2010, 11:22 AM   #26
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QuoteOriginally posted by tcom Quote
With the Pentax F 1.7x AF converter, the AF of the lens will not move. You do prefocus manually on the lens, and the camera together with the moving lens in the converter will perform the fine focusing. It makes this with all lenses, no matter if the lens is MF, traditional AF or SDM AF.

I contacted Pentax Germany and told them I found a brand new 1.7x af converter and due to the notice and the manual asked if Pentax is indeed producing it again. The answer is not telling if the TC is produced again, the answer just said that Pentax is not allowed to sell this TC in Europe due to ROHS regulations (Restriction of the use of certain hazardous substances).
Tcom:
Those are truly awsome photos, congrats!
Now the question:
Pentax is coming out with this "new" F 1.7x AF TC, and yours seems to be exactly the same one. When and where did you buy this one which you used for those pics?
Is the "old" F 1.7x AF TC still available somewhere ... anywhere?

Now regarding the pre-focusing with this TC: that is completely acceptable and very suitable for anyone doing wildlife/bird photography. As long as there is some sort of focus confirmation, and the fact that the TC's moving elements with fine focus .... that's great.
Even if the AF of the lens itself will not move, as long as you can fine focus ... that's all that matters.

Cheers

JP
01-01-2010, 11:35 AM   #27
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Thanks JP.

From the IQ, I could not find any single difference between the "old" and the "new" version.

The shots shown here were taken with the "old" version. I think this version is not available anymore in new condition, but it does appear fromtime to time used on ebay.

I found the "new" version on ebay.
01-01-2010, 11:49 AM   #28
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QuoteOriginally posted by tcom Quote
Thanks JP.

From the IQ, I could not find any single difference between the "old" and the "new" version.

The shots shown here were taken with the "old" version. I think this version is not available anymore in new condition, but it does appear fromtime to time used on ebay.

I found the "new" version on ebay.
Thanks, Tcom.
I look forward to get one of those. I have a Tamron 1.5x, which works well with the DA*300 but it's always nice to get a little closer!

Happy New Year.

JP
01-01-2010, 12:09 PM   #29
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QuoteOriginally posted by tcom Quote
I contacted Pentax Germany and told them I found a brand new 1.7x af converter and due to the notice and the manual asked if Pentax is indeed producing it again. The answer is not telling if the TC is produced again, the answer just said that Pentax is not allowed to sell this TC in Europe due to ROHS regulations (Restriction of the use of certain hazardous substances).
Then how do I get one?
01-01-2010, 12:12 PM   #30
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I ordered it from a seller from China (on ebay)
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