Sigma 30mm F1.4 Feedback

[yeoenghwee]

Hi all,

I would like to get a feedback on the Sigma 30mm F1.4 from the clubsnap users. Apparently, I got a used set from the forum and I find that when shooting wide open, there is some sharpness issue at the centre with 100% crop. I also find the CA quite back even stopping down at F8. Not sure if it is my lens issue or the it is suppose to be like that.

Need all your kind respond on this. I am using it on my Canon 60D.

[PerspectiveDiary]

Your lens is most likely the cause. Did you use another lens to test if you get similar results? The lens should be sharp in the center especially if you've stopped it to f8.

[yeoenghwee]

Hi Perspective Diary,

At F8 it is sharp in center but the CA fringing issue is across the aperture. Even at F8 there are fringing issue. You have the same issue? Doe F1.4 to F2 have the center softness as well?

[PerspectiveDiary]

Mine is relatively sharp wide open at a 100% crop. I'm not sure on your standard of sharpness though. CA is not so obvious at 100% crop at F8.

[pachero]

TS, can you post a picture here so that we can have a better idea?

My experience with this lens is very very good. That's why I am always puzzled as to what all the issues raised by others are...anyway at F8, everything should be nice and sharp, so if there's a problem, everyone should be able to spot it at a glance

[yeoenghwee]

Sigma 30MM F1.4
IMG_0191 | Flickr - Photo Sharing!

Sigma 30MM F4
IMG_0193 | Flickr - Photo Sharing!

Sigma 30MM F1.4 center crop
IMG_0191 Crop F1.4 | Flickr - Photo Sharing!

Sigma 30MM F4 center crop
IMG_0193 Crop F4 | Flickr - Photo Sharing!

[yeoenghwee]

Anyone can help review the images and advice? Thanks to all csers.

[wolfton]

Anyone can help review the images and advice? Thanks to all csers.

Brudder, bring the lens out and shoot real life and see if you experience any of the issues you mentioned. If you still do, then probably something wrong, but my guess is you will not experience any problem in real life shooting....

I will shred away the focus chart if I am you......

[PerspectiveDiary]

Ya..why not try shooting like what wolfton had mentioned. There's a reason why the Canon 35mm 1.4L is priced way above the Sigma. :P

[yeoenghwee]

Hi all,

Precisely it is because when I shoot life indoor that I find it a little soft that is why I tried the focusing chart which shows the CA issue. But then the softness could be my issue as well. Just want to confirm before I decide if I want to pend the extra oaf and time down to sigma if it can be calibrated.

[wolfton]

Hi all,

Precisely it is because when I shoot life indoor that I find it a little soft that is why I tried the focusing chart which shows the CA issue. But then the softness could be my issue as well. Just want to confirm before I decide if I want to pend the extra oaf and time down to sigma if it can be calibrated.

Oh, so you have already shot real world. @ f1.4 SOOC, without any PP, there will be some degree of softness, regardless of whether you use the Sigma or L lenses. Bump up sharpness in post, and you should see it improves. If there is still no difference, maybe you can bring it down to Sigma to check. They will advise you if there's any problem. If the technician did not find anything wrong, they will tell you there. Then it could be your user mistake when taking the pictures. Do understand that @ f1.4, the DOF is thin and focus do shift, thus the technique used in execution is pretty important.

Also just to add, I have a feeling that your test chart shooting is set up wrongly. Just my gut feel after seeing the angle of shoot. Maybe others may want to confirm this

[Shadus]

Oh, so you have already shot real world. @ f1.4 SOOC, without any PP, there will be some degree of softness, regardless of whether you use the Sigma or L lenses. Bump up sharpness in post, and you should see it improves. If there is still no difference, maybe you can bring it down to Sigma to check. They will advise you if there's any problem. If the technician did not find anything wrong, they will tell you there. Then it could be your user mistake when taking the pictures. Do understand that @ f1.4, the DOF is thin and focus do shift, thus the technique used in execution is pretty important.

Also just to add, I have a feeling that your test chart shooting is set up wrongly. Just my gut feel after seeing the angle of shoot. Maybe others may want to confirm this

Agree. Mainly coz is F1.4, you have to be extremely precise. The test chart looks slanted slightly. You may want to re-setup on the vertical wall and and camera on tripod or horizontal with camera above it. We're talking about a tiny softness here so precision is very impt

[phoeniix]

Don't really own a 30 1.4 but was wondering if this review (along with CA charts and blur index) would help you better understand your lens

[yeoenghwee]

HI All, Thanks for the feedback and advice. I guess from all the information gathered, Sigma 30mm f1.4 is technically soft wide open and taken high challenge on the auto focusing when shooting wide open.

[SilentSeth]

You can check some full size samples here: Full-size sample photos from Sigma 30mm F/1.4 and determine yourself.

On the drop down list, just choose the aperture from f/1.4 to f/1.4 to display only wide open shots.

I personally think it's reasonably sharp provided you get a good copy. If not, you can calibrate your lens or do MF adjustment if your camera body has that function.