Another Lens Choices Thread

Khrest

Khrest

Khrest

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Loughborough
So I recently upgraded from a 30D to the 70D and have now realised, as you do, that the 7 year old Sigma 17-70 that I use as a walk-around should be upgraded also.

I'm visiting California in July and have been taking an interest in Landscape shooting, having achieved good results with the above lens four years ago out there.

After much agonizing I have concluded that the only setup that is affordable for the price I'm prepared to pay (around £700), is the current version of my old lens (now with IS and slightly wider top end at F4) and another Sigma lens, the 10-20 F3.5. However there's a fair overlap there, so am I getting value out of the lower end of the range?

I have a reasonably sharp Canon 55-250mm to cover the zoom end so I'm only really looking to cover the shorter end with the best glass I can afford. As is usual, the more I look, the more I get confused and annoyed that I can't just lay down the moolah for a set of L lenses :(
 
I started with the original Sigma 17-70 on my first camera, the 400D.

The best replacements would be the 15-85 or 17-55, but both would use up most of your budget.

Any crop-focused walkabout lens will be around 15-18mm at the wide end and will thus overlap somewhat with a dedicated ultra-wide such as the Sigma 10-20 or Canon 10-22. That said, 10mm is still significantly wider than even 15mm.

If you're prepared to buy used, you could get both the 15-85 and a Canon 10-22 within your budget or the 17-55 and 10-22 for a little more.
 
CGrieves said:
Just interested - What's actually wrong (or limiting you) with the 17-70?
Click to expand...

This I'd keep the current 17-70mm and add an ultra wide if that's what you fancy. The upgrade to the new sigma isn't going to be noticeable unless you really crave the stabilisation.
 
CGrieves said:
Just interested - What's actually wrong (or limiting you) with the 17-70?
Click to expand...

1) It was initially the desire to have IS
2) The IQ isn't there anymore compared to my 40D (which I no longer have unfortunately so cannot test). On wide apertures I'm getting a very low rate of sharp images. I did a few tests this morning and even through live view, I couldn't get a sharp image of a printed page. I dont see it being a case of calibrating within the camera, as I gather it doesnt use the micro adjust settings for live-view mode.

The 55-250 Canon I have works a dream, 75% of images are sharp and live view images are always sharp. This suggests maybe the Sigma has a calibration that worked with the 40D but is now out with the 70D.
 
Khrest said:
1) It was initially the desire to have IS
2) The IQ isn't there anymore compared to my 40D (which I no longer have unfortunately so cannot test). On wide apertures I'm getting a very low rate of sharp images. I did a few tests this morning and even through live view, I couldn't get a sharp image of a printed page. I dont see it being a case of calibrating within the camera, as I gather it doesnt use the micro adjust settings for live-view mode.
Click to expand...

That depends what focus mode you're using. If it's set to Quick Mode, then the screen will go black temporarily as it flips the mirror back down and uses the standard AF sensor, which would still be affected by any focus calibration issues.

If using the slower contrast detect AF mode where the image doesn't disappear during focusing then this wouldn't be affected by any lens-body calibration issue. Might be worth comparing the results of each method.

I've owned the Sigma 17-70 and both the Canon 15-85 and 17-55. The Sigma is a decent lens but I've found both the Canons to be a noticable improvement.
 
Having just done a few more tests on the Sigma, in live-view, it 'overshoots' on a test image every time. That's using the non-quick mode and the x10 magnification. The Canon lens exhibits none of these properties, which leads me to believe it's something with the Sigma, not the body. I did notice that after the overshoot, if I touch the manual focus wheel it will move back by around 0.5mm before the AF mechanism prevents further movement, that is enough to produce a sharp image. I'm tempted to think I've somehow picked up a play in the focus mechanism, but surely the Canon should continue trying to focus until it actually gets sharp in live-view, rather than giving up after one attempt every time. I have tried both focus modes; the one where it should hunt forever doesn't make any improvement, it still stops, thinking it has found focus when it hasn't.
 
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