# Sigma 14mm f1.8 star photo



## BeenThere (Apr 20, 2017)

Finally a shot where some idea of coma performance can be discerned. My take on this low res photo is that there is some coma, but probably something I could live with.

http://sigma-global.com/en/lenses/cas/product/art/a_14_18/testshot/index.html


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## Light Sculptor (Apr 20, 2017)

To me this looks better than some other 14mm lenses, and now I am potentially excited by this lens!


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## meywd (Apr 20, 2017)

So many lenses to dream about...


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## chrysoberyl (Apr 20, 2017)

The Sigma shot makes me glad I got the Rokinon 2.4. The other shot does not even look like coma but it does look like star trails.

Thanks for posting!


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## KeithBreazeal (Apr 20, 2017)

chrysoberyl said:


> The Sigma shot makes me glad I got the Rokinon 2.4. The other shot does not even look like coma but it does look like star trails.
> 
> Thanks for posting!



The outer edges will tend to be star trails. When taking time exposures, the outer edge star trails will be noticeably longer. Short exposures will have a much lesser effect, but still there.



Auroras over Lake Tahoe © Keith Breazeal by Keith Breazeal, on Flickr



Perseids &amp; Milky Way 11 Aug 2013 © Keith Breazeal by Keith Breazeal, on Flickr


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## Sharlin (Apr 20, 2017)

chrysoberyl said:


> The Sigma shot makes me glad I got the Rokinon 2.4. The other shot does not even look like coma but it does look like star trails.



The one that has elongated stars is taken with "another manufacturer's 14mm".


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## [email protected] (Apr 20, 2017)

Crap. Coma looks fantastic. Blew my lens money on the 135.


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## applecider (Apr 20, 2017)

I just saw this from sigma as well, the stars look pretty good in the corners at 1.8 and 2.8. But this is from sigma directly, I'd like to see a third party review address this issue before I put out money. Plus the new lens is quite weighty, and who knows the price in US $ ?

Keith on the star trails is the elongation in periphery true for shots not shot at North Star? I think it depends on the orientation of the camera and length of exposure. For a 14mm lens 500/14 or 35 seconds should be free of star trails (without magnification) at any direction. Your Lake Tahoe shot is 334 seconds thus the trails, though it is true they are longer the further from aimed at Polaris.


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## chrysoberyl (Apr 21, 2017)

Sharlin said:


> chrysoberyl said:
> 
> 
> > The Sigma shot makes me glad I got the Rokinon 2.4. The other shot does not even look like coma but it does look like star trails.
> ...



Correct; it does not look like an honest comparison. I expected better from Sigma. I'll wait for quality reviews.


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## chrysoberyl (Apr 21, 2017)

[email protected] said:


> Crap. Coma looks fantastic. Blew my lens money on the 135.



Ha - I'll take it off your hands for $1K. I want one, too!


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## rfdesigner (Apr 21, 2017)

*Sigma Astro-tests 14mm f1.8*

Came across this today.. it's quite possible someone else here has noticed it too, but I couldn't see any reference and the results do look good.

very good indeed.

http://sigma-global.com/en/lenses/cas/product/art/a_14_18/testshot/index.html


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## docsmith (Apr 21, 2017)

*Re: Sigma Astro-tests 14mm f1.8*

First time I have seen the link...thanks.

If that holds up, we may finally have the astro lens people have clamoring for. I'll wait to see some vignetting tests, but I already had my eye on this lens. Granted, I do love my Rokinon 14 f/2.8.


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## applecider (Apr 21, 2017)

*Re: Sigma Astro-tests 14mm f1.8*

Yeah there is another thread here: http://www.canonrumors.com/forum/index.php?topic=32423.0;topicseen
I don't know how to merge them.


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