Canon 50mm 1.4 vs Sigma 50mm 1.4

[dendronepthya]

Autofocus in low light is a struggle many lenses have. I don't think it is unique to just the Sigma (although I've heard Sigma has had more issue than most). My 35mm 1.4 has to hunt around for AF lock in low light all the time but I guess it does depend on just how dark it is in the room. If there is a lamp on in the room, it's normally ok, but if it is just the light from a TV or something the lens is going to have a hard time.

 

[Recty]

I had a light on in the room but the baby was behind a small box so her face wasnt being lit up. I was far enough away and there was enough ambient light from the room light that I'm real surprised it would have troubles... My other lenses, including my 100m macro and the 24-70 I had would have focused just fine in that instance.

Not only did it miss focus on one, but 4 out of 5 shots were horribly misfocused. The bad thing is the focus light came on like it had a focus and then I took the picture. It wasnt as if I was shooting in the dark and just clicking away hoping I got a picture, all signs indicated everything was focused.

I finally was able to get in touch with Sigma just 5 minutes ago, the lady said the rattle definitely isnt normal (she has the same lens and it doesnt do that) and that in the factory they calibrate the lenses. Sometimes that calibration doesnt work for my camera body, so I'll need to send the lens in along with the camera and they will calibrate for that.

I'm not sure I'm willing to do that, I'm debating just returning the Sigma and getting the Canon instead.

 

[dendronepthya]

Yeah, if the Canon shows AF lock, it is not going to be horribly out of focus like that. Oh well. The big knock on the Sigma is the inconsistent AF performance. It's interesting that there is no clear cut best 50mm out there. Even the 50mm f/1.2L has its issues with focus shifting and whatnot.

 

[Recty]

I know, it's kind of weird. It's actually seeming pretty impossible to find a good 50mm prime that does everything perfect. They all have their small problems, however, bad focusing ruins everything so to me the Sigma has the biggest problem.

I'll test this new lens I got today from Amazon and see how it does, but if the focus is at all funky, I'm just going to go with the Canon f/1.4.

 

[Jacob D]

<a href=showthread.php?s=&postid=15557632#post15557632 target=_blank>Originally posted</a> by dendronepthya
Yeah, if the Canon shows AF lock, it is not going to be horribly out of focus like that. Oh well. The big knock on the Sigma is the inconsistent AF performance.

That's not necessarily true. In low light, especiallt at wide aperture the AF may lock, but not necessarily precisely where you need it to.

It's interesting that there is no clear cut best 50mm out there. Even the 50mm f/1.2L has its issues with focus shifting and whatnot.

Well, there are a lot of great 50mm lenses out there... if you take AF out of the criteria

People who buy the 50/1.0 and 50/1.2 don't buy them for the AF, same goes for the 85/1.2, optically they are all superb. But I do agree with you. I don't know why Canon don't get their act together and fix the AF on the 50/1.4, I can understand that kind of performance on the 50/1.8 for < $100 but not on the 50/1.4

From what I have heard the Sigma 50 is better, but getting a good copy is the trick.

 

[Recty]

I'm on the fence about what to do. I took some pictures last night of a cactus and got really poor performance. I mean really poor. It was out of focus and just didnt look good at all.

I dont want to have to manual focus all my pictures, for sure. I'll keep testing this lens out for another week or so, but if it performs consistently poorly with focus issues then I'll probably return it and not bother trying to get another that works better. I'll most likely get the Canon version and see how that holds up.

I was really not too happy last night with the way the pictures turned out, it's almost like this second copy I got is even poorer at focusing than the first. And this wasnt even in low light, this was in the middle of a well lit room.

 

[dendronepthya]

Perhaps I am a huge novice, but I don't quite understand the point of a manual focus 50mm that is f/.95 or f/1.0. DOF is so thin at such big apertures that any slight move in the shooter or the subject would throw off focus. Am I missing something there?

Don't get me wrong, I love big aperture lenses (currently considering the 85L) but with no AF? I would get 1 keeper a month maybe.

 

[Jacob D]

<a href=showthread.php?s=&postid=15563617#post15563617 target=_blank>Originally posted</a> by Recty
I was really not too happy last night with the way the pictures turned out, it's almost like this second copy I got is even poorer at focusing than the first. And this wasnt even in low light, this was in the middle of a well lit room.

I don't have experience with the Sigma, but from what I gather a good Sigma vs. a good Canon - the Sigma should prevail in the AF department.

<a href=showthread.php?s=&postid=15563817#post15563817 target=_blank>Originally posted</a> by dendronepthya
Perhaps I am a huge novice, but I don't quite understand the point of a manual focus 50mm that is f/.95 or f/1.0. DOF is so thin at such big apertures that any slight move in the shooter or the subject would throw off focus. Am I missing something there?

Don't get me wrong, I love big aperture lenses (currently considering the 85L) but with no AF? I would get 1 keeper a month maybe.

At wide apertures you have to the nail the focus no matter how you do it (manually or auto). Some people are able to manually focus really well. It's tough for me though, even with an optimized view finder. Now manually focusing my Yashica Electro 35 GSN is another story

 

[Recty]

I'm still going back and forth on whether or not I want to keep the lens.

For one, it just isnt that sharp at f/1.4. That's pretty much the entire reason I bought it...

Secondly, it seems like the focus is only good through a certain range. Between 3 and about 8 feet, it focuses decently enough I'd keep it, but farther away than that it it seems to be missing the focus a lot.

Here are a couple pictures I took a little bit ago. They were both taken at F/1.4 and ISO 400, shutter speed of 160. The shot glass I attribute to just the very shallow DOF, but I dont ever really see anywhere on the glass that it is 100% in focus, it seems to me like it missed focus totally. It was close, but not on. The one of my wife was pretty bad actually, I had to do a lot of work to make it seem good and even then, it doesnt really feel sharp for me even dead center. Because of DOF, it's impossible to tell how the corners are for sharpness but I suspect they are very low.

I'm going to a sea life center Saturday which will be the real test of the lens and I'm really torn, I almost dont want to even bring it along because I'm afraid if I use it, those shots will suck.

 

[dendronepthya]

Are you using single point AF? I found that helped me a lot.

 

[Recty]

Yep, single point AF, using the direct center focus point.

 

[Jacob D]

Set up a quick test scene for yourself. Put some items with detail in front of and behind your intended focal plane, and take a few (say 10) shots in RAW. View the files with default or low level of sharpening.


Choose a spot near your focus point and look at 100 % mag:
<a href="http://www.flickr.com/photos/30740619@N08/3842752585/" title="2009-08_2697 by Dinardi Family, on Flickr"><img src="http://farm3.static.flickr.com/2489/3842752585_c193058506_o.jpg" width="811" height="1014" alt="2009-08_2697" style="border:4px solid #FFF;"/></a>


Now come back to reality and look at it at 50%
<a href="http://www.flickr.com/photos/30740619@N08/3842752569/" title="2009-08_2697 400x500_50percent by Dinardi Family, on Flickr"><img src="http://farm4.static.flickr.com/3460/3842752569_3ae9e49d0a_o.jpg" width="400" height="500" alt="2009-08_2697 400x500_50percent" style="border:4px solid #FFF;"/></a>


Last make an overall crop of the scene, resize it, and apply *a little* web sharpening to it:
<a href="http://www.flickr.com/photos/30740619@N08/3842752575/" title="2009-08_2697 640x800 by Dinardi Family, on Flickr"><img src="http://farm3.static.flickr.com/2607/3842752575_9997bb3c20_o.jpg" width="640" height="800" alt="2009-08_2697 640x800" style="border:4px solid #FFF;"/></a>


The first thing you should be able to see is whether or not your lens is front focusing or back focusing and how badly (if noticeable). Next get an idea for the overall sharpness and whether you are causing probs. with camera shake. Lastly see how well it takes sharpening and how you like the 'real world result'. At a reduced size on the computer screen with *a little* sharpening it should look nice and sharp.

I focused on the camera-right eye where the upper part of the eye meets the head. I took a similar shot and focused where the lower part of the eye is hidden behind the nose. In the latter case the camera focused on the nose throwing the eye out of focus (I didn't post this shot). Just because there is contrast there to lock onto doesn't mean the camera will get it right; it can't tell that the edge of the nose and eye have distance between them along the axis of the lens. At f/1.4 this is just reality, technique is critical.


(disclaimer, the above was set up super fast while I'm eating a sandwich )

 

[Recty]

Well I havent gotten to try your test yet, but I've been taking pictures of my fish quite a bit today (didnt get to go to the sea life center like planned) and the lens is really focusing poorly quite often. I think my first copy was real good except for the noise, and the second copy is the poor focusing like some people have posted about.

I'm debating what I want to do now, either send both back and get the Canon, which is probably what I'll do, or else send in one of the Sigma lenses to the factory and get it calibrated.

 

[Recty]

Just an update to this thread, I went ahead and returned both Sigma's and just received the Canon F/1.4 today. I havent gotten to test it yet, but I'm driving to another town this weekend and will be sure to test it down there. Hopefully it performs better than the Sigma.

I still dont understand how Sigma can make a lens that continually has focusing issues and still sell it and for over $100 more than the Canon version.

I got a Sto-Fen diffuser for my 580EX II, a lens hood and the Canon lens all for right at $400, whereas just the Sigma lens cost me $500, although it does come with a lens hood and a nice little carrying bag. But still, selling something that has a pretty good chance of failing a very important part of picture taking for $100 more than the "real" brand seems a little weird to me.

 

[wkahwkah]

ahhh damn I figured You'd send in lens and get it recalibrate it!
I have been debating between sigma 30mm and 50mm for while
and decide to get 50mm due to border to border sharpness and
contrast and was willing to send in for calibration for both since
Sigma had QC lol...
Hope mine is good copy (coming on Wed) and your canon copy
would be good, too

 

[Recty]

Yep, I hope your copy is good.

I cant really do without my camera for a week right now, I'm in the middle of building a website, so I cant send it in and just not be able to take pictures. As this business is being built I have to be snapping shots.

Two out of two Sigma lenses were bad for me, so I hope you have better luck.

 

[Emster]

How did it do?

 

[Recty]

Real good, I'm very happy with it. Leaps and bounds better than the Sigma, imo. The Sigma boasts having less CA and it feels better built, but imo if it cant autofocus, it's barely above trash.

 

[boodlefish]

good to know i was looking at a similar lens now i will go for the canon. sorry you had to go through this but thanks for sharing.

have you gotten a replacement canon 50mm yet? how do you like it?

common we need some good news here

 

[Recty]

<a href=showthread.php?s=&postid=15673514#post15673514 target=_blank>Originally posted</a> by boodlefish
good to know i was looking at a similar lens now i will go for the canon. sorry you had to go through this but thanks for sharing.

have you gotten a replacement canon 50mm yet? how do you like it?

common we need some good news here

I made another thread here...

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1702140

That I took some pictures with the Canon 50mm F/1.4, not all are with it but the first batch are.

It's an impressive lens, very sharp and focuses well.