# More Sigma Primes Coming? [CR1]



## Canon Rumors Guy (Mar 11, 2011)

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<strong>Sigma adding to the prime lineup

</strong>With the success and quality of the Sigma 50 f/1.4 and 85 f/1.4, Iâ€™m told theyâ€™ll be adding more fast primes to the lineup over the next 18 months.</p>
<p>Lenses on the horizon may include a 24 Ã‚ f/1.4, 35 f/1.4 and 135 f/2.</p>
<p>Sigma will also continue to update lenses by adding OS to them. The 300 f/2.8 may be the first to get OS along with the 500 f/4.5. With the pricing of the new Canon lenses in these focal ranges, I wouldnâ€™t be shocked to see Sigma do something 20% cheaper.</p>
<p><strong><span style="color: #ff0000;">c</span>r</strong>
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## theenginedriver (Mar 11, 2011)

Good news. I have my Sigma 30mm f/1.4 on my 7D probably 80% of the time, and I'd love to try out a 24mm.


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## Bob Howland (Mar 11, 2011)

I though the 300 f/2.8 had been pretty much killed by the 120-300 f/2.8. As for the 500 f/4.5, I think it would make more sense to make a 200-500 f/4 OS, but that's probably just me.


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## foobar (Mar 11, 2011)

24mm f/1.4 please! ;D


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## tzalmagor (Mar 11, 2011)

If those would be as good as the Sigma 85mm f/1.4, I'm likely to buy the 135mm f/1.4 & the 24mm f/1.4


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## Flake (Mar 11, 2011)

Sigma's primes are not without their problems though. The 50mm in particular suffers from focus shift when stopping down, the issue is worse on Canon cameras because the autofocus has the more sensitive f/2.8 centre point as opposed to other makes on f/5.6. When you focus with the lens wide open at say F/2.8 the focus is at one point, when the shutter is released the aperture snaps down, and the point of focus moves, in many cases ruining the shot.

This has been the issue many users have reported since the lens was released. On the other hand Canon's own f/1.4 although optically good suffers reliability issues, and should really be replaced. The 80mm f/1.8 is a very good lens, cheap too, it's difficult to see why anyone would pay a lot more money for a one stop advantage (especially if it suffers focus shift).


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## Fleetie (Mar 11, 2011)

Flake said:


> Sigma's primes are not without their problems though. The 50mm in particular suffers from focus shift when stopping down, the issue is worse on Canon cameras because the autofocus has the more sensitive f/2.8 centre point as opposed to other makes on f/5.6. When you focus with the lens wide open at say F/2.8 the focus is at one point, when the shutter is released the aperture snaps down, and the point of focus moves, in many cases ruining the shot.
> 
> This has been the issue many users have reported since the lens was released. On the other hand Canon's own f/1.4 although optically good suffers reliability issues, and should really be replaced. The 80mm f/1.8 is a very good lens, cheap too, it's difficult to see why anyone would pay a lot more money for a one stop advantage (especially if it suffers focus shift).



Could you explain what causes the focus shift? Why would the point of focus move when the iris closes to the setpoint (unless that causes other things to move in the front-to-rear direction)?

I also really like Canon's 85mm f/1.8, and my copy of the 50mm f/1.4 has been fine so far, so again, I'm happy with that. Having bought, and immediately returned, a bad copy of the Sigma 30mm f/1.4 (it was terrible), I'm wary of Sigma lenses. OTOH right now it's a non-issue, cos I'm still paying off the 24-105 f/4 L! So nothing at all is gonna get bought for a couple of months!

Thanks.

Martin


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## Stuart (Mar 11, 2011)

foobar said:


> 24mm f/1.4 please! ;D


 x2

Really this would rock the boat a bit, with canon currently charging over a Â£1000 for their version of this 24mm lens and the 50mm f1.4's being much closer in price at about Â£300s- maybe an affordable amatuer level.

I'm guessing canon prices would drop a bit or they would nedd to make a f1.2 version to stay ahead.

Nice for us togs.


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## Grummbeerbauer (Mar 11, 2011)

Fleetie said:


> Could you explain what causes the focus shift? Why would the point of focus move when the iris closes to the setpoint (unless that causes other things to move in the front-to-rear direction)?



Check this out:
http://toothwalker.org/optics/spherical.html

But while I heard a lot about _inconsistent _focus of the Siggy Fifty, I haven't heard about residual spherical aberations/focus shift in this one. However, the Canon 50 1.2 exhibits this problem quite clearly.
Check, e.g., this out for a serious discussion of the issue
http://photography-on-the.net/forum/showthread.php?t=371097
(or simply google for "50L focus shift"...)

and this for a more tongue-in-check view on the "50L focus issues" topic

http://fakechuckwestfall.wordpress.com/2009/05/31/ef-50mm-f1-2hell-usm/


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## Fleetie (Mar 11, 2011)

Grummbeerbauer said:


> Fleetie said:
> 
> 
> > Could you explain what causes the focus shift? Why would the point of focus move when the iris closes to the setpoint (unless that causes other things to move in the front-to-rear direction)?
> ...



Thanks; I see now.

And that last link: That was some funny shit!


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## Etienne (Mar 11, 2011)

Fleetie said:


> Flake said:
> 
> 
> > Sigma's primes are not without their problems though. The 50mm in particular suffers from focus shift when stopping down, the issue is worse on Canon cameras because the autofocus has the more sensitive f/2.8 centre point as opposed to other makes on f/5.6. When you focus with the lens wide open at say F/2.8 the focus is at one point, when the shutter is released the aperture snaps down, and the point of focus moves, in many cases ruining the shot.
> ...



Here's review of the sigma 50 1.4 at photozone (http://www.photozone.de/canon-eos/521-sigma50f1450d?start=1 ). The graphic near the bottom is pretty self-explanatory. The effect is due to residual aberrations, and it is bad lens design. Focus moves back about 2 cm when stopping down to f4. That's pretty bad.

You can get good focus using live-view, and by f8 the DOF is so big that your focus point will be covered and you will not see this effect. Of course there is no effect at f1.4, but it will be quite annoying between f2 - f5.6, and this is the only reason that I bypassed this lens: f1.4 is soft, focus is unreliable for f2.0 - f5.6, and I have plenty of other options for good shots at f5.6 and above.


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## Flake (Mar 11, 2011)

Thanks to everyone who saved me having to find the links to answer that one!

The problem is worse on Canon cameras because of the f/2.8 centre spot I'm told.


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## MK5GTI (Mar 11, 2011)

Why is this only a CR1? I want them now.

if they really come out with those, i will buy the 35/1.4, and 135/2 for sure. can't afford the canon version.

had the 30mm 1.4 before, love it, but went FF and i had to sell it.

I have been waiting for this for ever!!!!

a suggestion for Sigma would be a 24-105L or nikkor 24-120 F4 equivalent for ~$6-700 USD street price.


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## JLN (Mar 12, 2011)

a 35 1.4 could be quite a winner, the canon's is both lustworthy and unaffordable for most 

OTOH, a 135 2.0 would have to be pretty spectacular and pretty cheap, as canon's is already both.


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## GMCPhotographics (Mar 13, 2011)

I hope Sigma update their 500mm f4.5 to be a true f4. The additonal OS system would be sweet but the real fun with a 500mm begins with a 1.4x TC...which would still AF well with an f4 design.


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## AJ (Mar 14, 2011)

... and I think Sigma would do well to spec a 135 mm prime at f/1.8


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## MK5GTI (Mar 15, 2011)

AJ said:


> ... and I think Sigma would do well to spec a 135 mm prime at f/1.8



that would require filter size in the 8xmm size


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## tzalmagor (Mar 15, 2011)

MK5GTI said:


> AJ said:
> 
> 
> > ... and I think Sigma would do well to spec a 135 mm prime at f/1.8
> ...



Wouldn't 75mm suffice ?


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## AJ (Mar 15, 2011)

tzalmagor said:


> MK5GTI said:
> 
> 
> > AJ said:
> ...



Yes. In practice you'll end up with a 77 mm filter.

Canon's 135/2 has a filter size of 72 mm. Same as the 200/2.8


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## MK5GTI (Mar 31, 2011)

AJ said:


> tzalmagor said:
> 
> 
> > MK5GTI said:
> ...



135 divided by 2 is only 67.5mm, with the barrel thickness, they end up with 72mm filter size
135 divided by 1.8 is already 75mm of opening, + barrel thickness, i don't think 77mm (+2mm) can do, thats diameter, not radius


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## neuroanatomist (Mar 31, 2011)

MK5GTI said:


> AJ said:
> 
> 
> > Yes. In practice you'll end up with a 77 mm filter.
> ...



It probably _could_, the barrel is not thicker than 1 mm (so 2 mm added to the diameter). But it depends more on the optical design of the lens - my guess is that a larger diameter front element will be used to reduce vignetting, and an 82mm filter will be the result. More lenses are coming with 82mm filters these days (Canon 16-35mm II, which I'll point out increased in diameter from the 77mm filter used on the MkI version of that lens), the TS-E 24mm II (and the MkI version of that lens used only a 72mm filter!). 

In that regard, I really hope B+W comes out with an 82mm ND 3.0 (10-stops) - well, I've been told that they will not, but their parent company, Schneider Optics, might...


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## Bob Howland (Apr 1, 2011)

MK5GTI said:


> AJ said:
> 
> 
> > tzalmagor said:
> ...



Nice try but 200 divided by 2.8 is 71.4mm and, as previously stated, the Canon version uses a 72mm filter


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## nounours18200 (Apr 2, 2011)

> I hope Sigma update their 500mm f4.5 to be a true f4. The additonal OS system would be sweet but the real fun with a 500mm begins with a 1.4x TC...which would still AF well with an f4 design.



Me too: a supertele at a good price would be a best seller, but only if it is at a similar level of quality than the Canon 500/4... And this is maybe not a (so) easy challenge, because the level of quality to be reached is high, and the volume of sales not as high as for a basic 50mm...

The current Sigma 500/4.5 has two "problems" compared with the Canon 500/4 IS (not talking about the recent II version): it offers only f/4.5 so no AF when used with a x1.4TC and a non 1D body, and secondly its quality is not as high as the Canon... Despite its lower price, it is not enough to seriously challenge Canon on this top-class telephoto market .


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