# Sigma 14mm f/1.8 Art @ LensTip



## ahsanford (Jul 4, 2017)

Won't be long before we see the coma test heard round the world:

http://www.lenstip.com/2236-news-Sigma_A_14_mm_f_1.8_DG_HSM_-_sample_images.html


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## BeenThere (Jul 4, 2017)

Vignetting is much less than I expected. A good sign. I want to love this lens.


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## KeithBreazeal (Jul 4, 2017)

I sooo want to see a star field shot. The photos are pretty good but DOF makes it difficult to determine corner detail in these samples. CA is looking very minimal. So far, so good.


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## SecureGSM (Jul 4, 2017)

Vignetting wide open is at around 2EV level, quite noticeable but expected for such a bright UWA lens. Distortions are extremely low. I detect very slight barrel type distortion. No more than 2%. Chromatic aberrations are well controlled. 
So far so good.




BeenThere said:


> Vignetting is much less than I expected. A good sign. I want to love this lens.


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## Khalai (Jul 4, 2017)

SecureGSM said:


> Vignetting wide open is at around 2EV level, quite noticeable but expected for such a bright UWA lens. Distortions are extremely low. I detect very slight barrel type distortion. No more than 2%. Chromatic aberrations are well controlled.
> So far so good.
> 
> 
> ...



You can't avoid natural vignetting in UWA lenses. Even the perfect one will still have some...


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## KeithBreazeal (Jul 4, 2017)

One thing I'm really liking is the low distortion. I'm about 75% sold so far.
95% of my Rokinon 14mm use is night photography. We'll see how coma plays out.


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## tron (Jul 4, 2017)

SecureGSM said:


> Vignetting wide open is at around 2EV level, quite noticeable but expected for such a bright UWA lens. Distortions are extremely low. I detect very slight barrel type distortion. No more than 2%. Chromatic aberrations are well controlled.
> So far so good.
> 
> 
> ...


Check:

http://www.the-digital-picture.com/Reviews/Lens-Vignetting-Test-Results.aspx?Lens=794

Even Zeiss 15mm has much more vignetting than 2% (max 4% at the corners...)


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## SecureGSM (Jul 4, 2017)

Yes, but this is precisely what I said : expected for such a bright UWA lens. Expected means, well, Normal, right? 



Khalai said:


> SecureGSM said:
> 
> 
> > Vignetting wide open is at around 2EV level, quite noticeable but *expected for such a bright UWA lens*. Distortions are extremely low. I detect very slight barrel type distortion. No more than 2%. Chromatic aberrations are well controlled.
> ...


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## SecureGSM (Jul 4, 2017)

Hi tron,

Sigma 12-24 Art exhibits around 1.8% distortion level wide open and 12mm, not vignetting. So does new Sigma 14 F1.8 Art. To my eyes at least. 

If you are talking vignetting , then 4EV corners vignetting is an awful lot!  or are you mixed Vignetting with distortions and EV with percents?

AFAIK, Rokinon 14 F2.4 vignetting levels are similar at 2.4EV in extreme corners but distortions are more noticeable and mustache type?




tron said:


> SecureGSM said:
> 
> 
> > Vignetting wide open is at around 2EV level, quite noticeable but expected for such a bright UWA lens. Distortions are extremely low. I detect very slight barrel type distortion. No more than 2%. Chromatic aberrations are well controlled.
> ...


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## Khalai (Jul 4, 2017)

SecureGSM said:


> Yes, but this is precisely what I said : expected for such a bright UWA lens. Expected means, well, Normal, right?
> 
> 
> 
> ...



Check out Irix 15/2.4 lens. That thing vignettes like crazy. Almost -4 EV!


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## SecureGSM (Jul 4, 2017)

Irix? No thanks I love my Sigmas ;D

4EV is a shame though. If that lens used (wide open) for night photography, just imaging what 4 stop shadows lift will do to the noise levels. No thank you. 



Khalai said:


> SecureGSM said:
> 
> 
> > Yes, but this is precisely what I said : expected for such a bright UWA lens. Expected means, well, Normal, right?
> ...


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## tron (Jul 5, 2017)

SecureGSM said:


> Hi tron,
> 
> Sigma 12-24 Art exhibits around 1.8% distortion level wide open and 12mm, not vignetting. So does new Sigma 14 F1.8 Art. To my eyes at least.
> 
> ...


I meant 4EV vignetting not 4% Sorry.


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## tron (Jul 5, 2017)

I took the time to check the new Sigma 12-24 in lenstip. It shows very good behaviour in coma, distortion and vignetting. I am not interested in it but I just wanted to know how Sigma fares. Since they have done it once there is great hope for the new 14 1.8...


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## natek (Jul 5, 2017)

I just grabbed myself a copy. Any tests you guys would like to see? Hoping for a clear night to get at least some test shots. Anything else?

Regards,
Nate


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## ahsanford (Jul 5, 2017)

natek said:


> I just grabbed myself a copy. Any tests you guys would like to see? Hoping for a clear night to get at least some test shots. Anything else?
> 
> Regards,
> Nate



Um, let's see:


Coma
Have another look at coma
Vignetting
Check coma again

- A

P.S. Don't listen to me too seriously. I don't shoot astro -- I'm just parrot-ing why every superfast ultrawide has failed to meet astro shooters' (very very high) expectations the last few years: coma usually underwhelms.


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## natek (Jul 5, 2017)

So I did some first test shots: http://striking.ch/essays/2017/07/hands-on-sigma-14mm-18/
You can download full resolution jpgs and the raw files at the end of the post.

Hoping for a clear sky to shoot some astro tonight, although I will not be able to get to a perfect location.


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## cazza132 (Jul 5, 2017)

Thanks natek for your test shots.
Also found a good link for the astro folk.
Vignetting looks surprisingly good at f1.8! - probably as good or better than the Samyang XP 14mm at f2.4 (which seems to have a blue cast at the periphery when corrected).
Coma performance at f1.8 looks mixed with some shots looking reasonable and others looking a bit ordinary. This may depend on what part of the image is used to focus due to field curvature. It might be better to use stars close to the edge of the frame rather than the centre.
https://jackfusco.smugmug.com/Blog/Sigma-14mm-f18-ART-First-Images


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## BeenThere (Jul 6, 2017)

Thanks cazza for the link. A little hard to evaluate at the lower resolution, but definitely promising.


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## lkunl (Jul 6, 2017)

I found some astro shot at sigma website. It's just 6mp not full size but coma look good.
https://www.sigma-global.com/en/lenses/cas/product/art/a_14_18/impression/


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## Jopa (Jul 6, 2017)

lkunl said:


> I found some astro shot at sigma website. It's just 6mp not full size but coma look good.
> https://www.sigma-global.com/en/lenses/cas/product/art/a_14_18/impression/



Very impressive pictures! Yes, shot on a 5dsr and reduced to 6Mpx... why???


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## ahsanford (Jul 6, 2017)

Jopa said:


> lkunl said:
> 
> 
> > I found some astro shot at sigma website. It's just 6mp not full size but coma look good.
> ...



Also: from Sigma corporate. :

It's up to you, but you might want to wait for non-commissioned work.

- A


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## natek (Jul 6, 2017)

So i just updated my post with some astrophotography:
http://striking.ch/essays/

Conditions were less than optimal, we have summer right now and the city is not that far. But it should suffice to check if this lens might suit your needs.

Full resolution jpg and raw at the bottom of the post.

If you have any comments or wishes feel free. Astrophotography is absolutely not my field and I have nothing to compare the shots to.


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## SecureGSM (Jul 6, 2017)

natek, I detect strong decentering in your copy of the lens. hence your issues you are refering to:

1. Honestly, I found it hard to focus. When I focused in the middle of the frame, the corners were worse than that.
2. And each corner seemed to need a slightly different focus to get optimal results. 

top left corner exibits a pronounced coma aberrations whilst the top right corner is less affected.

I woud strongly suggest to either replace the lens ( if available) or get the lens fixed under warranty. I am sorry. hope it helps.




natek said:


> So i just updated my post with some astrophotography:
> http://striking.ch/essays/
> 
> Conditions were less than optimal, we have summer right now and the city is not that far. But it should suffice to check if this lens might suit your needs.
> ...


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## lkunl (Jul 6, 2017)

natek said:


> So i just updated my post with some astrophotography:
> http://striking.ch/essays/
> 
> Conditions were less than optimal, we have summer right now and the city is not that far. But it should suffice to check if this lens might suit your needs.
> ...




Thank for your sample pic. It's look like a coma of 14mm/1.8 is a bit better than Sigma 20mm/1.4 and not good as Samyang 14/2.4 XP but i really impressed with low vignette of 14mm/1.8.


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## natek (Jul 6, 2017)

SecureGSM said:


> natek, I detect strong decentering in your copy of the lens. hence your issues you are refering to:
> ...



Thanks, I was also thinking about that. Will test some more tonight, and also with f 2.8.
But luckily, SIGMA Support is very good where I'm at, so I don't expect too much problems if i have to exchange this copy.


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## natek (Jul 6, 2017)

if anyone is interested in some more raw files to peek at, I just added some more shots that I had time for during an event that I covered today: http://striking.ch/essays/


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## SecureGSM (Jul 7, 2017)

actually, not quite correct. as this copy of the lens exibits decentering issues, you should look at the best corner available: top right corner. it is virtualy coma free! and just to be fair, let's not forget that you compare Sigma at F1.8 to Samyang at F2.4. That is nearly a full stop of a difference.



lkunl said:


> ..It's look like a coma of 14mm/1.8 is a bit better than Sigma 20mm/1.4 and not good as Samyang 14/2.4 XP but i really impressed with low vignette of 14mm/1.8.


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## tron (Jul 7, 2017)

SecureGSM said:


> actually, not quite correct. as this copy of the lens exibits decentering issues, you should look at the best corner available: top right corner. it is virtualy coma free! and just to be fair, let's not forget that you compare Sigma at F1.8 to Samyang at F2.4. That is nearly a full stop of a difference.
> 
> 
> 
> ...


Decentering is very alarming. I remember Samyang 24 1.4being reported as having similar issues. Shame...


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## SecureGSM (Jul 7, 2017)

do not be alarmed, my friend. not enough meaningful data available yet. wait for lensrentals review. they do test for copy to copy variation and decentering routinely. I for one, do not believe that decentering being a "signature" issue of this lens. It should be no worse than 12-24 Art lens and that one is a very solid performer.

https://www.youtube.com/watch?v=IrZ1ngpWJc8




tron said:


> SecureGSM said:
> 
> 
> > actually, not quite correct. as this copy of the lens exibits decentering issues, you should look at the best corner available: top right corner. it is virtualy coma free! and just to be fair, let's not forget that you compare Sigma at F1.8 to Samyang at F2.4. That is nearly a full stop of a difference.
> ...


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## tron (Jul 7, 2017)

SecureGSM said:


> do not be alarmed, my friend. not enough meaningful data available yet. wait for lensrentals review. they do test for copy to copy variation and decentering routinely. I for one, do not believe that decentering being a "signature" issue of this lens. It should be no worse than 12-24 Art lens and that one is a very solid performer.
> 
> https://www.youtube.com/watch?v=IrZ1ngpWJc8
> 
> ...


I do hope you are right


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## chrysoberyl (Jul 14, 2017)

The LensTip review is out. Their copy definitely has coma.


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## BeenThere (Jul 14, 2017)

Alas, coma is not as great as hoped for, but it is within parameters that I can live with. I think that an aperture of 1.8, and vignetting of only 2 EV in the corners makes up for the slight coma shortcoming. This was confirmed to me by some star shots posted in another thread. Sharpness is also pretty good. Basically I'm sold on this lens for my Astro work at 14mm. Lenstip seems to agree, calling this lens the perfect astrophotographer's companion in the comment section of their review.

As a bonus, stopped down to f/5.6, it will make a great landscape lens. I would not hike with it though, given the weight. And I know the lack of filter options will bother some, polarizer is the only filter I use with some landscape images. Soon enough there will be an adapter from somebody.


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## ahsanford (Jul 14, 2017)

The coma test heard round the world:

http://www.lenstip.com/506.7-Lens_review-Sigma_A_14_mm_f_1.8_DG_HSM_Coma__astigmatism_and_bokeh.html

- A


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## NorbR (Jul 14, 2017)

chrysoberyl said:


> The LensTip review is out. Their copy definitely has coma.



Sure it has coma, but it's really quite low. 

Personally, I'm sold. I can live with coma like this in the extreme corners at 1.8. And at 2.8 it will absolutely rule the field of astrophotography. Coma virtually inexistant (Lenstip only shows it at 2.5, but it gives an idea), under 1 stop of vignetting (!) where the Samyang (both of them) and Irix have between 3 and 4 stops.

Another great job by Sigma


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## SecureGSM (Jul 14, 2017)

Vignetting on FF and wide open is rather -2.28EV. Still very good result. 



NorbR said:


> ... under 1 stop of vignetting (!) where the Samyang (both of them) and Irix have between 3 and 4 stops.
> 
> Another great job by Sigma


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## chrysoberyl (Jul 14, 2017)

NorbR said:


> Sure it has coma, but it's really quite low.
> 
> Personally, I'm sold. I can live with coma like this in the extreme corners at 1.8. And at 2.8 it will absolutely rule the field of astrophotography. Coma virtually inexistant (Lenstip only shows it at 2.5, but it gives an idea), under 1 stop of vignetting (!) where the Samyang (both of them) and Irix have between 3 and 4 stops.
> 
> Another great job by Sigma



LensTip shows that the coma at f/1.8 is definitely there, but it is better than the 20mm Sigma. Enjoy your new lens!


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## NorbR (Jul 14, 2017)

SecureGSM said:


> Vignetting on FF and wide open is rather -2.28EV. Still very good result.



I meant at f/2.8. Lenstip quotes -0.84 EV at that aperture.


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## SecureGSM (Jul 15, 2017)

Got, it. It is a very nice glass indeed. 



NorbR said:


> SecureGSM said:
> 
> 
> > Vignetting on FF and wide open is rather -2.28EV. Still very good result.
> ...


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## basketballfreak6 (Jul 15, 2017)

seriously guys...this lens is just freaking awesome, distortion control is magnificent, (at least my copy) did a pretty good job dealing with flare today as well, and the lens is SHARP

zero distortion correction here:



Sigma 14mm ART Sun Flare by Tony, on Flickr


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## andrewfusekpeters (Jul 17, 2017)

I agree this is at 1.8 and 25 seconds ISO2000 last night I love this lens ! Www.andrewfusekpeters.com


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## lkunl (Jul 18, 2017)

https://www.dpreview.com/articles/1717621214/astrophotography-with-the-sigma-14mm-f1-8-art-lens

Astro review of Sigma 14mm ART from dpreview.


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## nubu (Jul 24, 2017)

Did some Astrocomparison with the ef14/2.8II here: https://www.dpreview.com/forums/post/59871149


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## SecureGSM (Aug 28, 2017)

The Digital Picture: 

Just Posted: Sigma 14mm f/1.8 DG HSM Art Lens Review

"... Really. Nice. Lens..."

http://www.the-digital-picture.com/Reviews/Sigma-14mm-f-1.8-DG-HSM-Art-Lens.aspx


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## LonelyBoy (Aug 28, 2017)

ahsanford said:


> natek said:
> 
> 
> > I just grabbed myself a copy. Any tests you guys would like to see? Hoping for a clear night to get at least some test shots. Anything else?
> ...



It does make me wonder - how hard is it to control coma? Are the lens designers unaware of the thirst for coma improvements, or as with other things is it a tiny-but-vocal minority? Is it really expensive to control coma? Is it even possible to avoid it in fast UWA designs (has anyone done it yet)?

The sequence I've seen, over the years, of hope and disappointment with every single announcement and review of a new fast UWA has made those questions simmer in me for a while. They're serious questions, by the way, if anyone knows the answers - I really just don't, but the repetition of the cycle is fascinating.


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## basketballfreak6 (Aug 28, 2017)

LonelyBoy said:


> ahsanford said:
> 
> 
> > natek said:
> ...



i am no expert at this but i think it is just an inherent issue with UWA as coma as i understand is caused by light rays coming from an off-axis point of light compared to image plane (thank you google) as one could imagine be very difficult to correct in an UWA lens

what i think a lot of people gets mixed up tho (including me up until recently) is coma vs astigmatism, coma is where you get the comet tail effect whereas astigmatism is where you get the cross/bat wing looking effect

imho while coma and astigmatism is definitely present in the sigma 14 art it really only happens towards the extreme corners and i don't think practically speaking it affects the overall image much, i think sigma has done a great job overall with designing this lens



Milky Way over Glass House Mountains by Tony, on Flickr

edit: i had a look at TDP's review and feels my copy performs a little better in regards to astigmatism side of things...guess there is always going to be your copy to copy variation as well

edit 2: this is a seriously capable lens



First attempt at interior/real estate by Tony, on Flickr


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## JumboShrimp (Aug 30, 2017)

This thing makes me droooooooool ... ;D


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