09-29-2010, 12:06 AM
[quote name='Yakim' timestamp='1285706734' post='3332']
"Due to the heavy weight of the lens system the AF speed is Okay but it's nothing rave about." <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/sad.gif' class='bbc_emoticon' alt='
' />
I want the fastest AF possible and my experience taught me that in order to achieve that you need both IF (or RF) and ring-USM. If it had them, I might have been tempted. The 135/1.8 is too heavy and slightly on the long side (FL wise) for the A33. Now, if one may dream of a 100/2 makro with AF and IF.....
[/quote]
IF doesn't necessarily make a lens AF faster. It all depends on how many elements move to make IF possible, and on how complicated the movements are. Of course, really long lenses always have relatively speaking only very light and small lens requirements for IF, but the shorter a lens gets, the heavier these elements grow. And IF Macro lenses, unless they have a limiter, are not generally known for fast AF behaviour, and we're talking F/2.8 lenses here, not even F/2 ... <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' /> Ok, non-IF macros are really slow <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />.
Kind regards, Wim
"Due to the heavy weight of the lens system the AF speed is Okay but it's nothing rave about." <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/sad.gif' class='bbc_emoticon' alt='
' /> I want the fastest AF possible and my experience taught me that in order to achieve that you need both IF (or RF) and ring-USM. If it had them, I might have been tempted. The 135/1.8 is too heavy and slightly on the long side (FL wise) for the A33. Now, if one may dream of a 100/2 makro with AF and IF.....
[/quote]
IF doesn't necessarily make a lens AF faster. It all depends on how many elements move to make IF possible, and on how complicated the movements are. Of course, really long lenses always have relatively speaking only very light and small lens requirements for IF, but the shorter a lens gets, the heavier these elements grow. And IF Macro lenses, unless they have a limiter, are not generally known for fast AF behaviour, and we're talking F/2.8 lenses here, not even F/2 ... <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' /> Ok, non-IF macros are really slow <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....