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12-04-2011, 07:04 PM - 2 Likes   #1
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Most common TCs real magnification

I posted this short test results in DPR/Pentax SLR forum already. I'm re-posting it here for the others who may search this forum looking for some answers about most common Tele Converters.
This test was driven by Russell Evans remark in my last DPR/Pentax thread that ProMaster 1.7X in fact is something smaller X-magnification device. I took a shot of a measuring tape from 20ft with FA*300/4.5 alone and then took the similar shots with all my TCs attached one by one. Then I calculated a real magnification of every TC I have owned.
There is what I got:

Tamron 1.4X Pz-AF - 1.34X

Vivitar Series1 1.4X AF (a re-branded clone of the Tamron above with no PZ contacts) - 1.34X

Sigma APO 1.4X EX - 1.38X

Sigma APO 1.4X EX DG - 1.38X

ProMaster 1.7X Spectrum 7 Z AF - 1.5X (I also tried ProMaster on SDM driven DA*60-250/4 lens. It doesn't lock focus, constantly hunting with no stop)

Pentax 1.7X AFA - 1.7X

Bower MC7 2X Pz/AF (actually it is a high quality TC. It looks like it's a clone of ProMaster 2X Digital AF TC, but I can't confirm it 100%. The Pz markings is an over statement. There is a usual base for two Pz-contacts, but the contacts themselves are missing) - 1.82X

The only ProMaster and Bower (there is also identical Vivitar clone available, I believe) are different from what they are claimed to be. The Sigmas are almost spot on. And Tamron and Vivitar slightly less magnify than the Sigmas.

Last edited by Greyser; 02-01-2013 at 01:20 PM.
12-06-2011, 02:48 PM   #2
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In other words- budget brands are budget for a reason Nice test!

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12-06-2011, 06:50 PM   #3
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This test makes the Kenko 1.5X into a big liar too. It is pretty firmly believed to be identical to the Tamron 1.4X, therefore actually a 1.34X.
12-06-2011, 08:26 PM   #4
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QuoteOriginally posted by Adam Quote
In other words- budget brands are budget for a reason Nice test!
Thanks. It's very good point. I did not look into it from such an angle.
BTW: My FA*300/4.5+Tamron 1.4X Pz-AF combo is just exceptional!


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