New DSLR Owner...First lens (New Sigma 30mm 1.4)

I really wanted to start off learning manual photography with a prime. I really like the Sigma 30mm 1.4 and the Canon 50mm 1.4. The Canon 28mm 1.8 also looks nice, but I wanted 1.4.

I debated over the 30 vs 50 and decided on the 30 because it's closer to 50mm (35mm) with a 1.6 crop body. And if everything goes well, I would get the 85mm 1.8 .... I like how there would be a 55mm gap in between lenses. If I got the 50 instead of the 30, my path would probably be a 100mm f2 or 135mm f2. I wanted the 85mm cause I intend to shoot sports in high school gyms with it. And to be anal, I like that it would let in a more light than the 100, even if it is slight.

My concern is what if I get a bad copy? How do I know if the lens is bad, or my camera, or my lack of experience using a camera with manual settings? Chances are it would probably be user error but there seems to be a decent chance I could get a 30mm copy with focusing issues.

Once my camera and lens arrive, if I post images, would you all be able to tell if it was the lens? I don't want to blame the lens if it is me at fault, or vice versa.

Thanks

Well, I'd just take some pics and see how they turn out. The DOF of a f1.4 lens is very thin, so user error is sometimes an issue.

If you suspect a problem after some regular shots, try a chart.I've seen quite a few folks us this (see link below) which seems to work well.

http://focustestchart.​com/focus21.pdf

Thank you for the chart! I will definitely try it if I am not happy with my results.

themadman wrote in post #9869296
Well, I'd just take some pics and see how they turn out. The DOF of a f1.4 lens is very thin, so user error is sometimes an issue.

If you suspect a problem after some regular shots, try a chart.I've seen quite a few folks us this (see link below) which seems to work well.

http://focustestchart.​com/focus21.pdf

50mm is not long enough to use outdoors if you don't want to crop images to get better composition.
The 85mm is really great for that sort of thing.

Do a search here for Manual Focus Adjustment techniques. Grab a free focus chart and run some tests. You will quickly be able to tell if there is a problem with the lens. 40D doesn't have MFA so if there is a problem w/ the lens you will have to send it in.

Free focus chart here :

https://photography-on-the.net/forum/showthre​ad.php?t=750736

Darkwand wrote in post #9869372
50mm is not long enough to use outdoors if you don't want to crop images to get better composition.
The 85mm is really great for that sort of thing.

???

Surely this depends on what you are shooting? - Some would say its not wide enough...

I personally say it's a great field of view and will make you think about composition more than a zoom.

I have both the Sigma 30 and 50 and they both came with front focus issues. I sent the 30mm to CRIS in AZ and it came back perfect. The turn around time was a little over a week (most in transit time). I sent the 50mm to them and now waiting for it to come back.

If you are going buy Sigma, make sure you buy from an authorized dealer. Be prepared to send it off to get recalibrated. If you are one of the lucky ones that get one with no issues, then start playing the lottery.

If you buy used, make sure it was bought from a authorized dealer. If not, make sure you have a satisfaction guarantee or return agreement with the seller.

Darkwand wrote in post #9869372
50mm is not long enough to use outdoors if you don't want to crop images to get better composition.
The 85mm is really great for that sort of thing.

I have seen many thousands of images taken with this lens and I know it is capable of some of the types of photography I intend to shoot.

NinetyEight wrote in post #9869538
I personally say it's a great field of view and will make you think about composition more than a zoom.

This is exactly why I want to start learning on a 30mm ... and for low light, shallow dof.