Sigma 30mm f/1.4 EX DC HSM Lens for Canon Digital SLR Cameras: Customer Reviews & Product Details

I just requested a return from Amazon for this lens. As always, Amazon rocks.

Here's my two day experience with it attached to my Canon T1i:

I bought this lens wanting more light/speed and a more natural focal length compared to my Canon 50mm 1.8 (cropped sensor). Like most, I read tons of reviews and forum entries around this lens before purchasing. I was a little anxious when I first received it due to all the mixed reviews out on the web. I bought it knowing there was a chance I'd get a bad copy.

Everything about the packaging, exterior, weight, fit and finish of this lens is excellent. It just feels like a quality product during first impression. The included case is nice, the hood fits well, the lens connects snugly to the camera with a snap of confidence. The focus ring is nicely sized and has a proper amount of resistance.

The optics of this lens are impressive. The 2/3 extra stop compared to the Canon 50mm 1.8 will instantly spoil anyone. The reduced focal length was also fantastic. I shot my kids in my living room at night with a single light source in the room and was able to take great shots at ISO 400. The bokeh is beautiful.

I processed the first batch of raw images and noticed some missed shots from overall softness. Some were tack sharp and others weren't. I know with this DoF any slight change in distance from the target will cause this. There was also some distortion and vignetting, but nothing major. Other than that, the images were everything I had hoped from this lens.

As I continued shooting, I noticed more and more soft images. I think this got progressively worse over time as I used it. I tried out manually focusing and realized this lens wasn't auto focusing correctly. The manually focused shots were remarkable. I confirmed the lens was front focusing using a tripod and focus chart. This was very disappointing. I really hoped to get a good copy of this lens.

The second day I used it, the autofocus completely failed. My guess is the HSM stripped or something. As I was using the lens, the focus system stopped working and I was unable to take any more shots. I was able to keep turning the focus ring without it ever stopping. So that was it... I'm one of the unlucky ones to get a bad copy. I can understand how there are so many mixed reviews on this lens. When it worked and focused correctly, it was awesome for the price.

I think I'm going to save up and get a Canon 35mm 1.4L.

EDIT:

I decided to request a replacement instead of refund and tried out a 2nd copy of this lens. I got lucky and it was remarkably better than the 1st copy I received. This one is a keeper and I'm happy it only took one extra try to get a good one.

I had 3 copies of this lens. None of them were focusing correctly. Most of time it will front focus by 1 inch. It's kinda random, hit or miss. It's probably okay for many people but I am spoiled by other good prime lenses. Even when it was in focus, it wasn't sharp enough for me. You get what you paid for. It may work in certain situations like shooting in extremely low light. If you are picky about sharpness and image quality, stay away.

I have a Canon 40D and take lots of indoor sports shots. My 50mm 1.8 Canon (the inexpensive $120 lens) is great but I needed a prime lens that could capture more of the action and was still somewhat affordable. I was trying to decide between the Canon 1.8 28mm and this Sigma 1.4 30mm and am really happy that I chose this. Turns out that extra f-stop (or 2?... I'm still learning all the lingo) is totally what I need. I was worried about the focusing issues that people mention but seemed to get a good lens and also took people's suggestions to use 1.8 to get that "sweet spot". The images are really creamy and rich and would def recommend this.

Pros:
Center and large aperture performance
Standard field of view for APS-C cameras
Build quality
Value

Cons:
Poor corner performance

Bottom Line: This lens is the perfect focal length for APS-C. A 35mm lens on APS-C always seems not quite wide enough, and 28mm a little too wide. This Sigma at 30mm (I measured it at 31mm) fits nicely in between. It offers a large aperture for available light shooting, with excellent center performance wide open. If the corners were better it would be perfect.

I am using this lens for Pentax mount on my K-7 (note: the review page doesn't distinguish between lens mounts for this item). Focus has been extremely accurate, even wide open. I have no issue using any of the focus points. I don't know if I was lucky and received a good sample or if the Pentax K-7's special focus sensor that adjusts focus accordingly to light type (tungsten, daylight, etc) makes an improvement, all I know is that it works well.

For the Pentax mount the lens is screw drive and not HSM. The downside is it doesn't offer full time manual/quick shift like other HSM lenses, and the focus ring turns during AF operation. There is no manual/auto selector for Pentax mount like the image shows.

Corner performance is acceptable for portraiture work and anything where corner sharpness is not critical. One of the strengths of this lens is that it is good wide open, and rarely do you need excellent corner performance with the thin depth of field at f/1.4.

In Pentax mount, there is also the SMCP 31mm f/1.8 Limited lens, which is certainly an optically superior lens at the corners, but comes in at nearly 3 times the price. I would recommend this Sigma 30mm for those on a smaller budget. I think some of the online reviews are overly harsh on this lens, as they are looking primarily at test chart data and not images produced with the lens. I recommend this lens, and wish Canon and Nikon made something similar.

the auto focus is snappy. i'm very pleased with the pictures produced with this lens. I would recommend you buy this product.