Sigma 30mm f1.4 EX DC HSM

does 30mm crop lens on a full frame camera provide a 30mm focal lenght on full frame

Correct, it's the actual 30mm focal length.

llazlok wrote in post #15353292
Correct, it's the actual 30mm focal length.

But once you crop it, it is no longer the same field of view as a 30mm lens designed for FF. You are basically getting the same result as the 30mm lens on a cropped camera, maybe a bit wider if you can live with more vignetting or black corners.

^ OMG that is soo sharp, even on this bad netbook screen!

How is yours wide open? I've been realizing how careful I need to be when focusing and recomposing. I use center dot.. Other than that, I don't think my copy has front/back focusing issues....just low-light focusing issues in general

With the flash I've been using lately, this lens performs significantly better as well

My question is do you guys really see that much difference between 85 1.8 and 200 2.0 ?

Also does anyone else think that Sigma is the sharpest of all three?

All three of the following shots had white balance adjusted to 4600 and exposure was added on all 1 stop, and nothing else was touched.

Focus point on all three pictures is left eye of a dall in blue dress.

The last picture is the setup…. Two flashes and one disco ball…

First is Sigma 30mm 1.4 at 1.4 250 ISO-100
Second is Canon 85mm 1.8 at 1.8 250 ISO-100
Third is Canon 200mm 2.0 at 2.0 160 ISO-100
Fourth is my setup

Thank You!

Wide open this lens is moderately sharp but if I give it some help sharpening in photoshop, I can make it VERY sharp. I use back button AF to lock my center point onto my subject's eyes, then recompose and shoot with the exposure button. (separating these two functions in custom functions to two buttons really made a difference for me as far as AF accuracy when recomposing).

Darn it. I need to sell this lens because I'm going FF, but I can't bring myself to do it.

IMAGE LINK: http://www.flickr.com …s/noobography/8​271423438/

IMAGE LINK: http://www.flickr.com …s/noobography/8​270331135/

Sirrith wrote in post #15364261
Darn it. I need to sell this lens because I'm going FF, but I can't bring myself to do it.

Don't woory, on FF you've got the excellent 35mm f/1.4 from Sigma!
Everything's gonna be ok!

blackjack999 wrote in post #15365214
Don't woory, on FF you've got the excellent 35mm f/1.4 from Sigma!
Everything's gonna be ok!

I don't like 35mm on FF that much though I'd need the 50 1.4, but I know they're going to update it sooner or later, and when they do its going to be fantabulous, so I want that.

With 40D:

Wow this thread is dead. I have exciting news about my siggy 30...... After thoroughly testing the lens at different apertures and distances focusing on a ruler (makeshift focus indicator), I found out my lens has been front focusing....!!! Really unfortunate, but I have solved the problem... Once I use autofocus with the back focus button (center dot), I turn the focusing ring a tiny bit counterclockwise. Maybe 3-4 degrees (out of 360). This is enough to now make 8-9 shots out of 10 perfectly in focus! Is really quick and it's not very hard to adjust it pretty much the same amount every time.

I really don't feel the need to have this sent in for calibration I went from having like 0-1 out of 10 perfectly in focus to about 8-9...probably in focus due to improperly focusing and recomposing.

I guess that once you get used to the quick adjustment you are all set. But that is frustrating, the lens should be good out of the box.

I am on my second copy, the first would not focus at all. With the second one I always get the feeling it is off a bit. I just love the low light flexibility this lens gives me.