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12-17-2013, 03:12 PM   #16

Join Date: Oct 2011
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QuoteOriginally posted by goubejp Quote
Forget that. Results are good with the 1,4L, poor with the 2L (I tried both). No walkaround, must buy a long lens for birding - I went for the FA*600 and it's a great lens.
The 1.7x looks quite good. I had a 1.4x-L for a bit that I tried on the Tamron, but sold it since I thought the regular small 1.4x Tamron TC actually looked better with that lens. Now I will have to see if I can pick up another one without spending a fortune. I do have a more recent 7-element Vivitar/Kenko 2x TC that is not bad optically, but tends to add PF. Hoping to get this thing out to the park this week so I can do some real tests...

12-17-2013, 03:45 PM   #17
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I wonder if there's adjustment screws under the rubber focus grip, like the A70-210/4 has.
12-17-2013, 03:49 PM   #18
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I think the adjustment screws under the rubber grip on the A70-210 F4 are the same as the 3 screws under the trim ring on an A50 F1.4, you only loosen them (or they loosen themselves) to adjust the infinity point and then re-tighten them fully. I may be getting confused though.
I had to re-adjust and tighten them in the field on my A70-210 F4 when they decided to come loose and infinity skidded out of adjustment with an ugly scraping sound. Luckily the rubber grip held them to the lens so they didn't get lost.
12-18-2013, 11:16 AM   #19
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The A70-210/4 has 4 screws on the lens mount side of the rubber grip, in slots. They put pressure on an aluminum ring. It's a one-touch zoom so the adjustment is partly focus damping and partly limiting zoom creep, with some tricky adjustment stuff too.


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