I got the Sigma 16mm F1.4, but not sure if lens is OK

[AHM]

I bought the Sigma 16mm F1.4 from Amazon (or, to be precise, my wife bought as a birthday present for me). Here is the thing: it was shipped without any box, instructions, warranty information. It was not even bobble-wrapped. It was just put in plastic bag and then into a box with some books. No protection. I would imagine it's fragile and could have been damaged by that treatment?

Because of that I'm not sure if it's as sharp as it's supposed to be. I attach one picture at F1.4. I cannot really judge if it's as sharp as it's supposed to be, or if it has been damaged by the shipping.

 

[AHM]

Here is the same picture taken with my Samyang 12mm at F2. I would say it's about equally sharp.

 

[someguy50]

But the Sigma is a stop faster

 

[AHM]

Looking at the pictures side-by-side, the Samyang is clearly sharper, but not much. My question is that perhaps that is true for the Sigma lens in general (not as sharp as the Samyang), or is my lens damaged?

 

[AHM]

Here is another comparison with my 35mm F1.8. I would say the Sigma is sharper. So, perhaps that's just how it is (nothing wrong with my lens): Samyang > Sigma > Sony in terms of sharpness.

Of course none of these tests are quite fair: different focal lengths and F-numbers.

 

[Mike_Italy]

From my personal tests the sigma 16 give its best fro f2.0 to f5.6. F1.4 is good but a bit soft.

Try compare the samy 12 with sigma both at f2.0...

 

[AHM]

From my personal tests the sigma 16 give its best fro f2.0 to f5.6. F1.4 is good but a bit soft.

Try compare the samy 12 with sigma both at f2.0...

Here is a comparison at f/2. I think the Sigma is sharper in the center, but the Samyang is clearly sharper at the edges.

 

[AHM]

Well, looking closer: at one corner the Samyang is clearly sharper, but in the other corner the Sigma is clearly sharper. Possible that I'm not exactly perpendicular to the bookshelf, and with the narrow DoF a corner could be out focus.

So, it seems at f/2 it's about equal. Of course, AF-S does not really work at f/2, I had to use AF-C for the Sigma lens.

Also, it seems my Sigma lens is OK in spite of the rough handling by Amazon. Still, thinking of returning it and getting a new one just to be on the safe side.

 

[sgkoala]

I suggest to also take photos using Flexible Spot Medium and putting the AF point in each corner and side. Make sure each turns out sharp.

My Sigma 16/1.4 appears to have a bit of mild field curvature so the edges are not flawless when taking photos of brick walls at wide apertures... for taking photo of a subject on a flat plane, if you are very picky about the edges you may wish to stop down to f4 then there’s enough depth of field to overcome the mild field curvature.

However, I find the sharpness at AF point excellent even at f1.4, (no matter where in the frame I put the AF point), and the bokeh very smooth at most distances.

 

[sgkoala]

Well, looking closer: at one corner the Samyang is clearly sharper, but in the other corner the Sigma is clearly sharper. Possible that I'm not exactly perpendicular to the bookshelf, and with the narrow DoF a corner could be out focus.

You can confirm this by putting the AF point in the corner that was less sharp, and if it comes out sharp then it’s caused by DoF.

So, it seems at f/2 it's about equal. Of course, AF-S does not really work at f/2, I had to use AF-C for the Sigma lens.

Also, it seems my Sigma lens is OK in spite of the rough handling by Amazon. Still, thinking of returning it and getting a new one just to be on the safe side.

If you have A6300/A6500 you can use AF-S with AF in Focus Magnifier for accurate results at f2 also.

 

[CyeJoeBob]

Well, looking closer: at one corner the Samyang is clearly sharper, but in the other corner the Sigma is clearly sharper. Possible that I'm not exactly perpendicular to the bookshelf, and with the narrow DoF a corner could be out focus.

So, it seems at f/2 it's about equal. Of course, AF-S does not really work at f/2, I had to use AF-C for the Sigma lens.

Also, it seems my Sigma lens is OK in spite of the rough handling by Amazon. Still, thinking of returning it and getting a new one just to be on the safe side.

I suggest testing the lenses outside in the real world. A bookshelf at short distance is not perfect to test the corner sharpness at f/2.

 

[TJ61]

Well, looking closer: at one corner the Samyang is clearly sharper, but in the other corner the Sigma is clearly sharper. Possible that I'm not exactly perpendicular to the bookshelf, and with the narrow DoF a corner could be out focus.

So, it seems at f/2 it's about equal. Of course, AF-S does not really work at f/2, I had to use AF-C for the Sigma lens.

Also, it seems my Sigma lens is OK in spite of the rough handling by Amazon. Still, thinking of returning it and getting a new one just to be on the safe side.

I suggest testing the lenses outside in the real world. A bookshelf at short distance is not perfect to test the corner sharpness at f/2.

Would be curious to hear your reasoning for that. IMO, testing in the "real world" can very easily mask, or at least not allow you to see flaws in a lens. For example, two of your corners might be showing featureless sky -- how does that help?

At best, shooting in the "real world" might allow you to see some characteristic of a lens that can't yet be easily quantified, and which might give it a slight edge in one's overall scoring. But for testing something as fundamental and quantifiable as corner sharpness at f/2, I'd take a bookshelf over the ambiguous "real world" any day.

 

[sgkoala]

Well, looking closer: at one corner the Samyang is clearly sharper, but in the other corner the Sigma is clearly sharper. Possible that I'm not exactly perpendicular to the bookshelf, and with the narrow DoF a corner could be out focus.

So, it seems at f/2 it's about equal. Of course, AF-S does not really work at f/2, I had to use AF-C for the Sigma lens.

Also, it seems my Sigma lens is OK in spite of the rough handling by Amazon. Still, thinking of returning it and getting a new one just to be on the safe side.

I suggest testing the lenses outside in the real world. A bookshelf at short distance is not perfect to test the corner sharpness at f/2.

Would be curious to hear your reasoning for that. IMO, testing in the "real world" can very easily mask, or at least not allow you to see flaws in a lens. For example, two of your corners might be showing featureless sky -- how does that help?

At best, shooting in the "real world" might allow you to see some characteristic of a lens that can't yet be easily quantified, and which might give it a slight edge in one's overall scoring. But for testing something as fundamental and quantifiable as corner sharpness at f/2, I'd take a bookshelf over the ambiguous "real world" any day.

Lens optical performance can vary significantly at different focus distances. If you bought the lens to use mainly at focus distances similar to that you are testing with the bookshelf shots then great (provided you make sure you are exactly perpendicular to the bookshelf). However, if you plan to use as a landscape lens with focus distances further away then I would suggest to test it at focus distances further away too...

The tester may also wish to consider how frequently they need very sharp corners at very wide apertures at a focus distance of a few metres, with the subjects simultaneously being on flat plane so that both the centre and corners are in perfect focus without any DOF issues. For me personally, it’s very rare to have a real life photo needing those criteria. Others may have this need all the time, who knows... point is to test the scenarios that you will actually use.

 

[JohnNEX]

Well, looking closer: at one corner the Samyang is clearly sharper, but in the other corner the Sigma is clearly sharper. Possible that I'm not exactly perpendicular to the bookshelf, and with the narrow DoF a corner could be out focus.

So, it seems at f/2 it's about equal. Of course, AF-S does not really work at f/2, I had to use AF-C for the Sigma lens.

Also, it seems my Sigma lens is OK in spite of the rough handling by Amazon. Still, thinking of returning it and getting a new one just to be on the safe side.

I suggest testing the lenses outside in the real world. A bookshelf at short distance is not perfect to test the corner sharpness at f/2.

Would be curious to hear your reasoning for that. IMO, testing in the "real world" can very easily mask, or at least not allow you to see flaws in a lens. For example, two of your corners might be showing featureless sky -- how does that help?

At best, shooting in the "real world" might allow you to see some characteristic of a lens that can't yet be easily quantified, and which might give it a slight edge in one's overall scoring. But for testing something as fundamental and quantifiable as corner sharpness at f/2, I'd take a bookshelf over the ambiguous "real world" any day.

https://www.google.com.au/amp/s/photographylife.com/what-is-field-curvature/amp

This is an issue particularly for testing wide angle lenses, which may have noticeable field curvature at close distances (like the bookshelf) but very little at longer distances (eg 10+ metres). Lens designs are about trade-offs and they will look to target best performance for the most commonly used situations, which is probably not 2 metres away.

I find that the side of a big building is a good test scene but getting precisely perpendicular is still a challenge, particular for the top and bottom of the frame. You really need to be a bit elevated compared to the scene.

Some people use a line of buildings on the horizon taken from a hill but you then have issues with atmospheric haze.

Finding a good WA lens test scene is tricky!

--
https://www.facebook.com/John-Clark-Photography-1035965476487072/

 

[Newbie Phewbie]

If you expected a new lens and it was shipped to you without a Sigma box w/manuals etc. and no packing to protect it, I would return it and file a complaint with amazon.

I've never had this happen to me & I use them a lot for all sorts of things.

 

[AHM]

Well, looking closer: at one corner the Samyang is clearly sharper, but in the other corner the Sigma is clearly sharper. Possible that I'm not exactly perpendicular to the bookshelf, and with the narrow DoF a corner could be out focus.

So, it seems at f/2 it's about equal. Of course, AF-S does not really work at f/2, I had to use AF-C for the Sigma lens.

Also, it seems my Sigma lens is OK in spite of the rough handling by Amazon. Still, thinking of returning it and getting a new one just to be on the safe side.

I suggest testing the lenses outside in the real world. A bookshelf at short distance is not perfect to test the corner sharpness at f/2.

Would be curious to hear your reasoning for that. IMO, testing in the "real world" can very easily mask, or at least not allow you to see flaws in a lens. For example, two of your corners might be showing featureless sky -- how does that help?

At best, shooting in the "real world" might allow you to see some characteristic of a lens that can't yet be easily quantified, and which might give it a slight edge in one's overall scoring. But for testing something as fundamental and quantifiable as corner sharpness at f/2, I'd take a bookshelf over the ambiguous "real world" any day.

https://www.google.com.au/amp/s/photographylife.com/what-is-field-curvature/amp

This is an issue particularly for testing wide angle lenses, which may have noticeable field curvature at close distances (like the bookshelf) but very little at longer distances (eg 10+ metres). Lens designs are about trade-offs and they will look to target best performance for the most commonly used situations, which is probably not 2 metres away.

I find that the side of a big building is a good test scene but getting precisely perpendicular is still a challenge, particular for the top and bottom of the frame. You really need to be a bit elevated compared to the scene.

Some people use a line of buildings on the horizon taken from a hill but you then have issues with atmospheric haze.

Finding a good WA lens test scene is tricky!

 

[AHM]

If you expected a new lens and it was shipped to you without a Sigma box w/manuals etc. and no packing to protect it, I would return it and file a complaint with amazon.

I've never had this happen to me & I use them a lot for all sorts of things.

Exactly. From my testing it seems the lens is OK, it was not harmed. Still, too be on the safe side, I'm thinking to return it and get another one. Also, if I want to sell it sometime in the future, the box is valuable, I believe.

 

[AHM]

Since my other thread: https://www.dpreview.com/forums/thread/4277055 was locked, I will post my reply to that here.

I believe now that my lens is OK (although I might still return it and get a new lens, as explained above). But meanwhile, I have been testing the lens to see how well it works, to decide if it's worth it for me. My experiment was to take two pictures: f/2.8 and then f/1.7. The second result should be better due to a reduction in ISO. My results have been variable. In many cases it seems f/1.7 looses sharpness compared to f/2.8, completely erasing the gain in ISO. BUT, that might be due to focus error. I have a few examples, where f/1.7 does come out sharp, so I'm thinking focus error. I am using AF-C, knowing about the focus issues with Sigma lenses. The pictures have been of my kids, and focus can be a little tricky. One could say that testing sharpness on kids is not the best test, but this is one type of real-world pictures I care about, not pictures of bookshelfs, so that is my criterion. And the criterion is that the pictures should come out sharp, including focusing. As said, a few have come out sharp at f/1.7, so perhaps the lens itself is actually sharp.

I'm a little vary of posting pictures on my kids on the open internet, so I'm still debating if I should include some test images.

 

[RGBCMYK]

Maybe it was an open box? All Sigma lenses come in a box and inside their box is a structure that supports the lens during shipping. No manual or warrantee information? This sounds like an open box or not from Amazon. Definitely needs an Amazon intervention

 

[TJ61]

If you expected a new lens and it was shipped to you without a Sigma box w/manuals etc. and no packing to protect it, I would return it and file a complaint with amazon.

I've never had this happen to me & I use them a lot for all sorts of things.

Exactly. From my testing it seems the lens is OK, it was not harmed. Still, too be on the safe side, I'm thinking to return it and get another one. Also, if I want to sell it sometime in the future, the box is valuable, I believe.

Yeah, completely agree this is unacceptable -- I wouldn't even waste my time checking the lens to see if it's OK.