Sigma 30mm/1.4 DC lens on EOS 30D Body

[larry h.]

Has anybody tried this combination? Is it true that the latest Sigma lenses

have firmware fixes for future incompatibility problems so it will never need

a hardware re-chipping? If you haven't used this lens on a 30D, how about a

20D? Any incompatibilities encountered?

 

I have read all the threads about this lens (most came out right after the

lens debutted). Any long term thoughts? Have people been returning this lens

as not sharp enough, etc.?

 

Here's a real braintwister: This lens was designed for the slightly larger

1.5x sensors on Nikon, etc. Because of that, is there any chance someone has

tried a 62-58mm step-down ring with this lens? Please, no speculation, just

answer if you have thought to and actually tried it. It sure would be nice to

be able to share 58mm filters with my other primes.

 

Thanks in Advance, Larry

[mark u]

It seems that in Canada this lens is one of many now sold with a 10 year warranty - which makes Canon's miserly one year seem very mean, and should allay your fears:

 

http://www.gentec-intl.com/Default.asp?mode=win&warr_in=com&warr_id=4211&prod_id=EXDC30C

 

Bear in mind that in the digital world there is a much greater chance of camera firmware being faulty than lens firmware, since the camera is a much more complex instrument - indeed, when the 20D was released it took Canon several iterations of firmware before it operated without locking up the camera with Canon's own lenses, never mind third party ones. A number of people have reported that Sigma now can update lens firmware, rather than having to replace dedicated chips. This has to be a smart move on their part, since it lowers costs if they can minimise the difference in hardware for providing lenses in different mounts, as well as giving future proofing via firmware update possibilities, and increasing customer confidence in their current products. The downside is that Sigma are now selling their lenses at less of a discount to equivalent OEM lenses than they used to.

 

Electronics and firmware issues aside, some users have reported problems with getting a sharp copy with reliable AF. It's very likely that a good proportion of those have little idea of their own errors in using a lens with such a shallow depth of field. It seems that almost all those who had a genuine "problem" lens found that Sigma service fixed it if they were given the chance. Here's a whole bunch of user experiences:

 

http://forums.dpreview.com/forums/read.asp?forum=1029&message=18533773

[yakim_peled1]

>> Is it true that the latest Sigma lenses have firmware fixes for future incompatibility problems so it will never need a hardware re-chipping?

 

No. Only Canon lenses can guarantee you that.

 

Happy shooting,

Yakim.

[mark u]

I disagree with both parts of Yakim's answer.

 

The evidence is clear that Sigma now employs updateable firmware in at least its better current lenses (unlike in the past - basically pre 2001). Several users have reported being able to visit a Sigma service centre and have the firmware electronically updated there and then, taking just a few minutes. Disassembling the lens and soldering in a new chip would take a whole lot longer.

 

Secondly, although Canon has the advantage of knowing the details of design of all their cameras and lenses, that offers no guarantee of forward compatibility without problem. I would cite the notorious history of the 70-200 f/2.8 L IS lens, which worked well with the bodies that were in production when it was released. However, with a number of later high end bodies, it often caused intermittent lockups and required expensive out of warranty repairs. Canon appear finally to have redesigned the IS unit which seems to have been at the heart of these problems - but owners of older lenses have been left to pay for the upgrade themselves. Be aware also that Canon have decided not to offer any form of extended warranty on DSLRs, which leaves scope for them to leave users in the lurch. The 20D problem I cited above is another case - although Canon obviously had a high incentive to correct the firmware problems with a newly released body.

[yakim_peled1]

<p> Mark, note the word <b>never</b> in the question. When <b>never</b> is stated then no third party manufacture can offer that. And BTW, I am far from being anti third party or anti Sigma. Sigma has some great lenses out there and <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00GCgC&tag=">I even consider buying one</a>. I just think that in most cases it's best to pay more and get more. </p>

<p>And the 70-200 IS issues are not compatibility problems but a bad design ones. Just as those in the 24-105/4, 70-300 IS and other instances. The bad service its customers were given is indeed a black spot (sp?) on Canon's coat. </p>

<p> So, is Sigma perfect? No. Is Canon? No. However, when it comes to compatibility problems, I stand by my statement. </p>

 

<p> Last point. Larry, you may find <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00G6ao&tag=">this</a> and <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00G9o7&tag=">this</a> posts of interest. </p>

<p> Happy shooting, <br>

Yakim. </p>

[slichtyler]

I know this doesn't help with the issue of firmware fixes or step-down rings -- but I would

like to post a picture in response to the fears of autofocus and sharpness. I'd heard a lot of

concern about these problems before I bought it, but I'm more than happy with the

results. This is a fairly small crop (top center) from a larger image (click for 100%):

<p>

<center><a href="http://www.plumgreen.com/color/fencepost2b.jpg"><img

src="http://www.plumgreen.com/color/fencepost2b.jpg"></a></center>

<p>

That's the Sigma 30mm on a Canon 30D, f/1.4 and 1/8000s. I can't complain about the

edge sharpness, and the focus seems to be bang on....

[mark u]

If you read Larry's question carefully he asks whether "it will never need hardware re-chipping", not whether it will never need a firmware upgrade. Since these lenses rely on firmware, the only way they'd ever need a new chip would be if the microprocessor or firmware ROM actually failed.

 

Secondly, I was objecting to your use of the word "guarantee". Canon's guarantees last a miserly one year, and beyond that you are on your own, paying for upgrades. Moreover, they do NOT guarantee that current equipment will work on future bodies - just consider the whole line of EZ flashguns as one example, never mind the whole orphaned FD system.

 

The Sigma 30mm f/1.4 can even be used on a 5D (try doing that with EF-S lenses without at best invalidating your warranty):

 

http://forums.dpreview.com/forums/readflat.asp?forum=1029&thread=18558148

[yakim_peled1]

Mark, I don't want to fight and I know the EZ and FD issues. I withdraw the word "guarantee", O.K.? And about EF-S? If you recall, I was one of the major critiques of that move. But I still think that for the long run, a Canon EF lens has a much better chance of surviving into the future than lens from any other company.

 

And thanks for the link. I have a 1D (1.3X) and one of the reasons I chose the 28/1.8 USM is its FF compatibility (turned out to be not a bad lens at all). I'll try to locate a friend with a 30/1.4 and compare the two.

 

Happy shooting,

Yakim.

[don_b__south_africa_]

Yowee, I'm having a serious problem with a Sigma 30mm on a new Canon 30D body. The Sigma front-focuses by miles, making it unusable. My Canon lenses focus perfectly on the same body.

 

Sigma in South Africa seems to disbelieve me and wants to blame the body. But why should Canon lenses be fine and Sigma ones not? Incidentally, I have a Sigma 10-20mm as well, and it also front-focuses on the 30D. The problem is less obvious because of greater depth of field.

 

Both Sigma lenses were spot-on when used on my 350D. Very puzzling.

 

Here are two 100% near-centre crops of pics taken with the Sigma 30mm and my Canon 24-70mm/2.8L. Both pics were taken with the same settings: 1/1500s, f/2.8.

 

http://www.pbase.com/glassbottle/focus_problems

 

In both cases the focus target was the edge of the roof of the house across the street. As you'll see, a fence about 20ft closer is what's in focus in the Sigma shot!

 

These results are typical, consistent and reproducible.

 

I wonder what the hell is going on. Anybody got any idea?

 

Don

[don_b__south_africa_]

See my message above. Sigma South Africa got back to me to say that Japan had looked at my sample pictures and decided that the focus on my Sigma lenses needed recalibrating. Japan is sending some special equipment to South Africa to enable the local agents to do the job. The equipment arrives on June 18.

 

If this sorts out the problem, I'll be impressed with Sigma's customer service.

 

I still can't understand -- and Sigma has not explained -- why the lenses should have been fine on a 350D but gone bananas on a 30D. Grateful for your ideas on the subject.

 

Don

[larry h.]

I still haven't bought this lens, but I am still interested. I read the article on dpreview that Mark U cited. It seems to imply that there is not much light fall off even with full frame sensors. But my question still remains: Can you put a 62->58mm step-down ring and a polarizer on it with out vignetting (as opposed to fall-off)?

 

Thanks, Larry