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Sigma 300mm f2.8 + 1.4x auto focus speed? (1 Viewer)
- Thread starter CCRII
- Start date
I used this lens's big brother (the 500 f4.5), Af was very fast even with a 1.4x tc, much faster than my 100-400 IS. I've had a look at the 300 f2.8 and it seemed to focus just as quickly, it's a cracking lens, I quite fancy one myself!
I really like the price point! Thinking about selling my 100-400 and upgrading.
Roy C
Occasional bird snapper
Most primes tend to AF faster than a zoom.
Not sure what you mean by really liking the price point of the 300mm f2.8 - it is three times the price of the 100-400.
but very attractive compared to the Canon 300 f2.8 IS
Roy C
Occasional bird snapper
Sorry, lost the plot there, I thought it was a Canon 300mm f2.8 that the OP was talking about but I see it is the Sigma.
Well I can get it for $2500 here in the states. Which makes it only $1100 more. But I would get the 1.4 tc which would add another $150. This would get me to f 4 instead of 5.6 (2 stops down) and get me a little more reach, also should be sharper since it is a prime while still being hand holdable for walkabouts. Maybe this is not the best way to go. If you have a better suggestion I am all ears though.
I wouldn't assume that a lens will be sharper than your 100-400 just because it is a prime. The Sigma 300 f2.8 is a very nice lens but at over 2.2kg it is not as easy a walkabout lens as the 100-400 and at ~ twice the weight and without IS it may well not be as easy to use handheld. Also f4 is only one stop faster than f5.6...
Roy C
Occasional bird snapper
Please read my previous post - I thought you were refering to the Canon 300mm f2.8.
I think I'm right in saying that full stops go in the sequence:
f1 f1.4 f2 f2.8 f4 f5.6 f8 f11 f16 f22 and onwards
other commonly seen figures such as f1.8, f4.5 and f6.3 are based on 1/3 of a stop increments.
Adding a 1.4x tc to a lens will increase it by one full stop, so an f2.8 lens will become an f4 or an f4.5 will become an f6.3. Using a 2x tc will cost you two stops so an f2.8 becomes an f5.6 and an f4.5 become an f9. I hope that helps!
Very much! Thanks!
