Originally posted by Artifarty Thanks. It seems like the 15 is more of a logical choice.... but 21 is US$160 cheaper. Any one has both 15 & 21 but ended up leaving 21 in the storage? The reason to purchase 21 is that Sigma 30 is a bit to big & heavy to carry in my bag for everyday use..... so 15/21/40/43 all seems to have the size/weight that i am after & i am open for suggestion.
My experiences:
(I don't have the 21 but I often use the kit lens as my 21mm).
1) DA 15 is crazy sharp and it's *possible* to crop to about 20mm without losing too much of your image size.
2) If you plan on taking wide-shots with people in them, the 21mm is much better suited to the task.
3) The 15 is best used for dramatic perspective, not "getting it all in". You can get it all in with any foal lengths if you move back far enough.
So yeah, the 15 is a great lens, but pretty special purpose. The 21 is great for wider shots with people ("environmental portraits / landscapes"), the 15 is great for drama / tight quarters ("perspective/pure landscape"). I personally think it's harder to take a good shot with the 15, but it's also more fun.
The main reason I got the 15 first? The kit lens could fill in as my 21 for now
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