I think I'm in Love again

Hi fellow Canonites! I just bought a Sigma 30mm f/1.4 and it's my first prime lens and boy is it fast!!!

But some things that concern me are this lens seems to be a hit-or-miss lens. At times the pics turn out blurry (seems to be mis-focussing, I rule out camera shake because the shutter speed is at 1/400). At other times, the pics are razor sharp at f/1.4. Nonetheless, the colors are brilliant and I love the vibrance produced by the lens.

Just a general question, do pics turn out blurry when you focus at infinity and use low aperatures?

I got very frustrated with the two copies I've tried of this lens, one front focused a lot, the other was so fuzzy nothing was in focus at any f/stop. Yet it is so much fun as soon as I have the funds, I'll be trying another copy. If you're worried send it to sigma to fix, I hear they're pretty good about it. Although why they don't just fix the design of the lens a bit makes me scratch my head. I told myself I'll try another copy if it stinks send it in to be fixed, if it still isn't great I just have to wait until I can afford the 35L.

you gotta be careful with your depth of field @ 1.4!!
it really is razor thin. if you're indoors, let your iso speed help you out. if i have no flash, i'm usually shooting at ISO 800 in Av mode.

try bumping it up to 1.8 or 2. you'll see the difference in just a couple stops.
you can still get some great shots around 1/100.

but yes, you're right. this lens is AWESOME.

Thanks for the quick replies.

I will surely go out and take more pics and experiment before I conclude if it's the lens fault or my fault. And yes, this is my first fast prime so I go crazy and shoot everything at f/1.4

There is something magical about the lens~ After taking two test shots with it, I just knew I had to buy it! Sadly I had to buy this second-hand and the warranty just passed. Do you know if Sigma still calibrates lenses after the warranty expires? For a small fee perhaps?

I assume they will. I had my old FD camera repaired at a shop, canon won't touch it due to it's age and that they don't touch the FD stuff any more, but a shop in Texas took great care of it (CLA.)

I love my Sigma. I routinely shoot indoors and wide open and it nails focus every time.

It's really not a "landscape/scenery" lens, so I don't think I've ever focused it at infinity. Works great on people though

After some more experimenting and analysis of the pics I've taken today, I've concluded that in many of the pics, the 30mm was indeed front focussing. The ones that I thought I nailed, after checking in ZoomBrowser, I realized that I had actually focused somewhere slightly behind the sharpest point but coincidentially the pic came out looking alright.

Anyways, I guess I'll have to call up Sigma tomorrow and see what they can do about my lens and expired warranty.

Thanks for your feedback guys.

The only complaint I have is the purple fringing that occurs when shooting wide open. Other than that, I love it.

Could you upload some front-focussed pics so we can see what you mean. Don't forget to add exif data (focus selection, aperture, shutter speed). There are some people here who can tell you what the problem is if they see the pics.

Sorry these are not the best examples (I think the JPEG compression doesn't help), but here are some casual snapshots from today...

Back focused? Focused on the fly... but the box behind the fly is sharpest

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I notice that all shots are a f/1.4. At this aperture, depth of field is very thin and if you move backward or forward as few mm you will miss focus. Did you use a tripod?
Handheld, you should increase your aperture setting.

I do a lot of portraits with my 50/1.4 and mostly shoot in the 1.4 - 2 range. I miss some shots mostly because my subject (my active 2 year old son) is moving, but I accept that because the shots that are good are really good.

I love this lens.I had to take my first copy back as it did have afocus issue but my second and current copy is a beaut. It's easy to miss your focus due to movement at f1.4 so if you're worried a test on a tripod is a must.

Newb question: how do you show the info including the focus point on a jpeg?

Use ZoomBrowser EX

do you know if Image Browser (MAC) would also do that?