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Taped Contacts - 1.4 X

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Author Topic: Taped Contacts - 1.4 X  (Read 367 times)
JohnC
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« on: June 20, 2009, 06:50:07 pm »

 Yes, that's a fair point re. the camera being fooled, so to test  that I  used the 70-200 and took a photo at the F4  it  appeared  to retain and then dropped it to f5.6 and there was a difference in the exposure- the f5.6 photo in the LCD was, of course darker , so it does seem that it actually does give you f4.  BUT lol.. I've just had a thought..I can hear you knowledgeable gentlemen saying "Ah but how do you know that it wasn't taking it at f5.6 (in reality) and the next photo you took was infact  f8 - well, that's a good point I didn't think of that at the time so what I'll do is to to take one photo at f4 with the extender taped and then take the extender off and take one at f5.6 and see if there's  any difference-- is this correct ?

My concern, though,  is that I can hear the lens hunting and wonder if it may damage the contacts somehow. When it hunts and assuming there is time, I can can go to manual get it focused and switch to auto and take the photo,  as and when, there may be a minimum of adjustment but no hunting. What I also found was that the hunting problem is mainly with hand held ,when it was tripod mounted the auto focus was fast, hardly, if any difference. However, the focusing without the extender was instant .
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