Sigma 12-24 f4.5-5.6 is it the perfect APS-c / FF lens?

Started Feb 10, 2013 | Discussions thread
OP G7D Forum Member • Posts: 50
Re: Sigma 12-24 f4.5-5.6 is it the perfect APS-c / FF lens?

G7D wrote:

wow thanks for that, yes i agree with most you say, CA i really do hate and currently my favourite lenses have the trade-off for more sharpness for around 2 pixel CA. Photoshop is very good not at correcting this, but i have said i really dislike it. Also flare concerned be, it really is extreme and the bulb seems unnecessarily large but i saw some images in bright light and feel maybe some creative angles or a hand over the sun could get around this. Consequently the 17-40 is the best I've seen for flare, but i doth think appropriate now on crop.

This where i get confused again, many people i've seen slate the 12-24 for its poor sharpness compared. However, when i compare it across the board the MTFs read 2400, 2200, 2200 at f5.6 at 12mm dropping to 2300, 1900, 1800 f5.6 at 24mm. the (II) version rates 0.8 pixels CA.

the canon - 2400, 2200, 2100 at f5.6 at 10mm and 2400, 1900 at f5.6 at 22mm so minimal differences and CA around 1.7 pixels MAX.

The sigma which was reviewed extensively on here was noted with minimal CA yet the tests show a range from 1.2 - 1.5 so i'd assume the 12-24 will not be an issue.

I think people may be confused with the old version sometimes

- but the Sigma 12-24 4.5-5.6 II from what i can tell

- minimal CA (in the range context)

- minimal distortion (slightly more than the old one and very complex - a trade-off for IQ)

- corner to corner good sharpness

this on full frame for example shows MTF of 3500, 2700, 2600 at f5 at 17mm

the Canon 16-35 II 3400, 2900, 2600 at f5.6 at 16mm

the tokina 16-28 3500, 3400, 3000 at f5.6 at 16mm

and as an example 17-40 3400, 2900, 1600 at f5.6 at 17mm

The rest of the factors seemingly say nothing between them, build quality and constant f-stop is good but at the +£1000 price tag, only the tokina around £500 is acceptable but not wide enough for a crop.

Again for comparison i'll include the TS-E 17mm f4 L which i consider the best landscape lens.

ignoring the fact it Tilt shifts for now - it is expensive, and doesn't zoom for adaptability and at the same focal length we see MTF, 3500, 3000, 2900.

At face value worse than the tokina but better than the canon - so if i can't afford the tilt shift and would get better use from a zoom than the unique TS ability in FF the Tokina is a winner. Ideally i want more zoom out of it but the quality is great and f2.8 could be useful.

however on crop it is too long - at 25.6mm it won't be much fun for now.

So again i may be wrong but i struggle to see the downsides - the tokina is again a bulb and awkward but i can attach filters like colin and lee stoppers on the hood so when FF i could still use the tokina. but for now i could use the 12-24 II on both and upgrade to the tokina if i feel necessary once FF?

any thoughts before i got out and spend all my money

 G7D's gear list:G7D's gear list
Canon EOS 7D Canon EF-S 18-135mm F3.5-5.6 IS Canon EF 100mm f/2.8L Macro IS USM Sigma 12-24mm F4.5-5.6 II DG HSM
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow