Sigma 50/1.4 EX DG - going back

rdh

rdh

Suspended / Banned
Messages
1,317
Edit My Images
No
Bought this lens yesterday, and very disappointed! Very sharp at f2, but really bad at 1.4 due to very inconsistent focusing. Wide open at 1.4, I found the majority of my shots being either front or back focused - I could not use this lens comfortably in the field. Exposure was inconsistent also, which I found baffling.

A quick google on the subject yielded this.

Will be picking up the Nikon 1.4G in it's place.
 
You are returning it for the same issues I have had with their 30mm F1.4 on a crop body.

Initially I thought it was my technique but I tried a canon 35mm F1.4 L and didn't have anywhere near as many misses on focus.

I know some people swear by the sigma fast primes, but after trying 3 difference copies (2 New one used) I have experienced the same sort of issue with each one. Inconsistent focussing. SHame, because the sharpness is awesome when the focus is correct!
 
I've just got one too and I'm very happy with it. It does forward focus at macro distances at F1.4, but I can't see why you would use it like that. The Dof at 1/2 a meter distance and F1.4 is 0.4mm! Even if you put the camera on a tripod how do you stop the model moving! Inconsistent exposure is most likely caused by cheap strobes which are not reliable shot to shot at low power. I'm assuming your using this lens for it's intended purpose?

And the link referred to Cannons which is a calibration issue, with the cameras.
 
Calibration can be camera, lens or both but in the review the problems were with front and back focusing which isn't a calibration issue, more likely a fault with the motor missing the mark.

Unfortunately the Sigma 50mm is widely reported to have QC problems but that's about par for Sigma and they are way past due for addressing this issue :(
 
Beagle - I was taking head and shoulder shot's on low light, with a selected AF point directly over the eye, and the image was coming out blurred four out of five times. I wouldn't buy a fast prime to use with a flash, I have 2.8 zooms for that.

The Nikon is meant to be slower at focusing, but reviews say it nails the focus each time. To me, that's far more important since subjects move about and you need to trust that if you can get only 1 or 2 shots, they are in focus. A faster focus that is either bias towards the front or back is no good to me, or anyone :¬)

Perhaps my copy is 'duff', but the Nikon is going to get a run regardless for comparisons sake.
 
I have the Sigma and mine is spot on and I know many other people who think the same. Sadly Sigma QC is not always the best but they do seem to be pretty good at replacing any duff copies.
 
The Nikon is meant to be slower at focusing, but reviews say it nails the focus each time.

Both myself and Richard Peters got duff Nikon AF-S with focus problems.

My swap-out was much better and focused spot on (as does my Sigma) - IMHO any lens that needs any sort of fine tune is defective, and Nikon agreed with me there :)

Did you buy the lens new?
 
puddleduck said:
The Nikon is meant to be slower at focusing, but reviews say it nails the focus each time.

Both myself and Richard Peters got duff Nikon AF-S with focus problems.

My swap-out was much better and focused spot on (as does my Sigma) - IMHO any lens that needs any sort of fine tune is defective, and Nikon agreed with me there :)

Did you buy the lens new?
Click to expand...

Yes new lens. I just tried the Nikon AF-S and it nailed focus in a very dark room every time, and it was literally tack sharp wide open (the Sigma wasn't). Yes, the motor is slower, but I can live with that quite easily.

Will be exchanging the Sigma for the Nikon early next week, and getting £50 back. Bargain :¬)
 
rdh said:
Yes new lens. I just tried the Nikon AF-S and it nailed focus in a very dark room every time, and it was literally tack sharp wide open (the Sigma wasn't). Yes, the motor is slower, but I can live with that quite easily.

Will be exchanging the Sigma for the Nikon early next week, and getting £50 back. Bargain :¬)
Click to expand...

You must have had a very bad copy because my Sigma is EXTREMELY sharp wide open. Also take a look at some of Pudleducks tests, A good copy of Sigma wins everytime.
 
lukewoodford said:
You must have had a very bad copy because my Sigma is EXTREMELY sharp wide open. Also take a look at some of Pudleducks tests, A good copy of Sigma wins everytime.
Click to expand...

That's cool, but I tried this Nikon myself and am very happy with the sharpness and focusing, so the thought of going through multiple Sigmas to find one that matches it is not very appealing :)
 
rdh said:
Beagle - I was taking head and shoulder shot's on low light, with a selected AF point directly over the eye, and the image was coming out blurred four out of five times. I wouldn't buy a fast prime to use with a flash, I have 2.8 zooms for that.

The Nikon is meant to be slower at focusing, but reviews say it nails the focus each time. To me, that's far more important since subjects move about and you need to trust that if you can get only 1 or 2 shots, they are in focus. A faster focus that is either bias towards the front or back is no good to me, or anyone :¬)

Perhaps my copy is 'duff', but the Nikon is going to get a run regardless for comparisons sake.
Click to expand...

I know the Nikon is a very good lens too, but as some others have seen AF can also be iffy. Personally I take Ken with a large pinch of salt! I hope you get sorted, either way they are both super bits of kit.
 
rdh said:
That's cool, but I tried this Nikon myself and am very happy with the sharpness and focusing, so the thought of going through multiple Sigmas to find one that matches it is not very appealing :)
Click to expand...

You don't have to go through multiple copies...sending it off to Sigma for re-calibration is an option. :)
 
Flash - that's not the problem since I use the 85/1.4 all the time, which doesn't have the same issues. The Sigma was not focusing on the AF point, regardless of distance/angle.

Beagle - anything Ken says is taken with a bag of salt :¬)

sdb - I've lost a lot of confidence in Sigma, which is an entirely personal choice of course. Calibration is an option, but like I said, the Nikon I tried was spot on, so I don't see the need.
 
You must log in or register to reply here.
Back
Top