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07-10-2010, 06:58 PM   #46
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QuoteOriginally posted by ghelary Quote
The point of a wideangle is about sharpness accross the range. Using a wideangle for portraiture for example will introduce perspective distortions with unpleasing consequences. Basically an ultrawide / ultrafast zoom is made for reporters and weddeing photographers needing to make interior shots. Now, in group picture, I'm not sure that Aunt Sally will be pleased if she sees herself all blurry because she's on the side of the frame. If you feel that I'm missing the point, please provide any example of picture where center sharpness is critical, border accessory and that can't be done by a longer lens.
If you're shooting a group wedding photo at f/2.8, you're begging for trouble. If you're not at 5.6 for DOF on human subject portraiture with the subjects NOT lined up flat across the frame (and most are not...boring) then Aunt Sally is going to be more concerned her new pearl earrings are OOF because the DOF was too shallow. She spent $600 on those for the wedding. They'd better look sharp for the record.

If the photog cannot get a reasonable DOF then they need more light (flash), NOT a wider aperture. And a WA for group photos will result in distortion. She's gonna look chubby. That is even true of the Nikon 12-24 WA, which does require a stopping down for sharpness, especially in a wedding group portrait photo!. Even still, no serious photog would shoot that shot at f/2.8 on a WA.

07-10-2010, 09:12 PM   #47
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QuoteOriginally posted by Aristophanes Quote
If you're shooting a group wedding photo at f/2.8, you're begging for trouble. If you're not at 5.6 for DOF on human subject portraiture with the subjects NOT lined up flat across the frame (and most are not...boring) then Aunt Sally is going to be more concerned her new pearl earrings are OOF because the DOF was too shallow. She spent $600 on those for the wedding. They'd better look sharp for the record.

If the photog cannot get a reasonable DOF then they need more light (flash), NOT a wider aperture. And a WA for group photos will result in distortion. She's gonna look chubby. That is even true of the Nikon 12-24 WA, which does require a stopping down for sharpness, especially in a wedding group portrait photo!. Even still, no serious photog would shoot that shot at f/2.8 on a WA.
+1 Smart answer
07-12-2010, 12:55 AM   #48
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QuoteOriginally posted by Angevinn Quote
The 16-28 would not be my first choice for family portraits or group shots. I love wide angle lenses but on FullFrame I would go more towards the standard to telephoto side of things. (35mm-85mm). There is correction software for barrel distortion out these days too. Nikon includes it in their RAW converter, Capture NX.
Well, sometimes, you simply don't have the space to step back. That's the whole point of ultrawides, for me.

QuoteOriginally posted by Aristophanes Quote
If you're shooting a group wedding photo at f/2.8, you're begging for trouble. If you're not at 5.6 for DOF on human subject portraiture with the subjects NOT lined up flat across the frame (and most are not...boring) then Aunt Sally is going to be more concerned her new pearl earrings are OOF because the DOF was too shallow. She spent $600 on those for the wedding. They'd better look sharp for the record.

If the photog cannot get a reasonable DOF then they need more light (flash), NOT a wider aperture. And a WA for group photos will result in distortion. She's gonna look chubby. That is even true of the Nikon 12-24 WA, which does require a stopping down for sharpness, especially in a wedding group portrait photo!. Even still, no serious photog would shoot that shot at f/2.8 on a WA.
While, I think that at 16mm, an aperture of 2.8 still provide a significant depth of field, I accept your point. But I don't think that change much of the debate. What the point then of a 2.8, ultrawide, FF, zoom ? Appart from the technical tour de force off coure.

As I said in a previous post 28mm FF, is already plenty enough on the wide side for many reason. I'm not trying to defend or to ditch this lens, just saying that I was not impressed by the sample pictures and that if it a 2.8, it has to be good accross the frame at 2.8. If you disagree with that, I would like to hear your arguments.
07-12-2010, 05:46 AM   #49
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The point of 2.8, even if a bit soft, is for stopping down headroom. Some WA start to get very sharp at f/3.5 within spitting distance of the edges. By f/4 they're all but pixelpeepingproofprintready, and by 5.6 it's as sharp as you'll get.

You won't get sharp across the frame at 2.8 from most lenses. You'll find this same debate in Leciawonderland.

If you're a wedding photog and you can't "step back" then maybe you've chosen the wrong location or have too many people wide across the frame. This sounds more like a composition issue.

I have a very good FF 24mm/2.8 Rokkor for my Minolta film camera. It's a fantastic lens, but still requires stopping down for frame sharpness. By f/4, on a 5x7 print, you can't tell. If it started at f/4, it would be an issue.

Most UWA are, therefore, landscape or large object (architecture) lenses. If you apply them to other scenarios (like the now famous DA15 thread), you'll get compromises. Note how the DA15 thread has exceptional photos isolating one subject in a very broad FOV, not many. This lens starts at f/4, controls flare, and is sharp enough wide open that you'd have to print the size of a minivan to see the difference between f/4 and f/8.

In many cases, what is really required beside a larger aperture is simply more light. Bounce the flash.

QuoteOriginally posted by ghelary Quote
Well, sometimes, you simply don't have the space to step back. That's the whole point of ultrawides, for me.

While, I think that at 16mm, an aperture of 2.8 still provide a significant depth of field, I accept your point. But I don't think that change much of the debate. What the point then of a 2.8, ultrawide, FF, zoom ? Appart from the technical tour de force off coure.

As I said in a previous post 28mm FF, is already plenty enough on the wide side for many reason. I'm not trying to defend or to ditch this lens, just saying that I was not impressed by the sample pictures and that if it a 2.8, it has to be good accross the frame at 2.8. If you disagree with that, I would like to hear your arguments.


07-12-2010, 09:00 PM   #50
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QuoteOriginally posted by Aristophanes Quote
The point of 2.8, even if a bit soft, is for stopping down headroom.
Your post was otherwise spot on, but I don't know if I agree with this point. Thinking outside of the range of typical wide-angle use gives lots of potential scenarios. Thin DOF might be preferred in a situation where you are using the WA for dramatic lines on a close-up subject but don't really need lots of sharp detail in the background. Also, for low-light where getting the impression of the whole scene is more important to you than having everything in focus, as in a concert perhaps. Shooting low-light candids in cramped quarters while retaining some sense of surroundings would be another potential use.

All I'm saying is that there certainly ARE legitimate reasons to have a wide angle 2.8, and that it isn't there simply to improve the sharpness at 5.6.

I agree with your overall thought, though, which seemed to be suggesting that corner to corner sharpness is not necessarily a reasonable expectation or need for such a lens wide open.
07-13-2010, 02:16 AM   #51
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QuoteOriginally posted by Aristophanes Quote
The point of 2.8, even if a bit soft, is for stopping down headroom. Some WA start to get very sharp at f/3.5 within spitting distance of the edges. By f/4 they're all but pixelpeepingproofprintready, and by 5.6 it's as sharp as you'll get.

You won't get sharp across the frame at 2.8 from most lenses. You'll find this same debate in Leciawonderland.

If you're a wedding photog and you can't "step back" then maybe you've chosen the wrong location or have too many people wide across the frame. This sounds more like a composition issue.

I have a very good FF 24mm/2.8 Rokkor for my Minolta film camera. It's a fantastic lens, but still requires stopping down for frame sharpness. By f/4, on a 5x7 print, you can't tell. If it started at f/4, it would be an issue.

Most UWA are, therefore, landscape or large object (architecture) lenses. If you apply them to other scenarios (like the now famous DA15 thread), you'll get compromises. Note how the DA15 thread has exceptional photos isolating one subject in a very broad FOV, not many. This lens starts at f/4, controls flare, and is sharp enough wide open that you'd have to print the size of a minivan to see the difference between f/4 and f/8.

In many cases, what is really required beside a larger aperture is simply more light. Bounce the flash.
Well, when I was speaking of not having the place, I was speaking about "in situation" picture, like taking the whole scene during the reception for exemple (and I doubt a flash can help to light even a scene with a depth and width of 20m) It happened to me 2 years ago, at a friend's wedding, with about 200 people dining by the candle lights, in exterior, I used then my fisheye and struggled to get a keeper, I would understand a pro using a rectilinear ultrawide at 2.8 even with the high iso capabilities of a D700 or 5DmkII. Of course, if you want everybody in line for a setup, you can choose the right place to use a longer lens.

But anyway, I don't agree with the "you need a very wide aperture so when you stop down, you get sharp pictures" the sharpness of the K50mm/1.2 is lower than of the K50mm/1.4 and both sharpness are lower than of K50mm/1.7 at common apertures. While all of them are quite good at all their apertures, what make a 50/1.2 much superior (and more expensive) than a 50/1.7 is not sharpness at F8, but the fact that it is usable at F1.2.

Now I understand that you may find this new usable at 2.8, but still, to me, if you need a lens only at F8 for DOF purposes, then you may choose a slower max aperture in a more compact package, to me that's definitively the strength of the DA15/F4.

BTW, did you see the latest test in Photozone ?

This Samyang looks to be a real winner if you can get with the few drawbacks. And the performance at F2.8 seems to be very good (albeit heavy vigneting)
07-13-2010, 05:03 AM   #52
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QuoteOriginally posted by Eigengrau Quote
Your post was otherwise spot on, but I don't know if I agree with this point. Thinking outside of the range of typical wide-angle use gives lots of potential scenarios. Thin DOF might be preferred in a situation where you are using the WA for dramatic lines on a close-up subject but don't really need lots of sharp detail in the background. Also, for low-light where getting the impression of the whole scene is more important to you than having everything in focus, as in a concert perhaps. Shooting low-light candids in cramped quarters while retaining some sense of surroundings would be another potential use.

All I'm saying is that there certainly ARE legitimate reasons to have a wide angle 2.8, and that it isn't there simply to improve the sharpness at 5.6.

I agree with your overall thought, though, which seemed to be suggesting that corner to corner sharpness is not necessarily a reasonable expectation or need for such a lens wide open.
Last comment is exactly my point. it's inherent in lens design to have corner softness at 2.8 unless the lens is 9cm across the front element and requires a sherpa to lug around! If you have subjects in the corner at a group wedding photo and feel "forced" to shoot at 2.8 with a WA, there's some awkward composition/location/lighting choices being made. You're going to run into softness and distortion effects.

There are many justifiable reasons to shoot wide open so long as the photog doesn't expect corner to corner sharpness, and is comfortable with some general softness. Those can be desirable features, so long as it is understood that sharpness once lost can never be regained. Photoshop has backed us into the "sharp everywhere, all the time" corner.

It's an outcome of lens design and optics and this is a discussion you have even in Leicaland.
07-13-2010, 06:06 AM   #53
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QuoteOriginally posted by Aristophanes Quote
Last comment is exactly my point. it's inherent in lens design to have corner softness at 2.8 unless the lens is 9cm across the front element and requires a sherpa to lug around! If you have subjects in the corner at a group wedding photo and feel "forced" to shoot at 2.8 with a WA, there's some awkward composition/location/lighting choices being made. You're going to run into softness and distortion effects.

There are many justifiable reasons to shoot wide open so long as the photog doesn't expect corner to corner sharpness, and is comfortable with some general softness. Those can be desirable features, so long as it is understood that sharpness once lost can never be regained. Photoshop has backed us into the "sharp everywhere, all the time" corner.

It's an outcome of lens design and optics and this is a discussion you have even in Leicaland.
Well, I think you didn't get my point either, in wedding photography (and for reporters) not all photos are setup with subjects waiting to be taken in front of the church, you may want to take the reception area (weither it is indoor or outdoor) and not be able to step back. You can't choose where you're shooting all the time, especially if you want the people to look natural.

Now, I'm not saying and I didn't say that the lens has to be as good in the corner as in the center, but as to be "good enough".

Anyway, I wouldn't take Leica as an example as their scale of value is a bit shifted. I've never seen a Leica lens being anything else but exellent in the tests

07-13-2010, 07:07 AM   #54
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QuoteOriginally posted by sjwaldron Quote
Isn't Tokina owned by Hoya? I don't think they would stop working together if that's the case.
Nope. There is some cooperation between Pentax and Tokina when it comes to APS-C lenses. But Tokina is still an independent company and has been sporting their own design lenses (also full frame ones) for a while now...
07-13-2010, 07:47 AM   #55
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QuoteOriginally posted by ghelary Quote
Well, I think you didn't get my point either, in wedding photography (and for reporters) not all photos are setup with subjects waiting to be taken in front of the church, you may want to take the reception area (weither it is indoor or outdoor) and not be able to step back. You can't choose where you're shooting all the time, especially if you want the people to look natural.

Now, I'm not saying and I didn't say that the lens has to be as good in the corner as in the center, but as to be "good enough".

Anyway, I wouldn't take Leica as an example as their scale of value is a bit shifted. I've never seen a Leica lens being anything else but exellent in the tests
If you are taking group shots at 2.8, you are asking for trouble. 4.0 is even touchy, depending on the size of the group.

Asking for corner-to-corner sharpness is fine if you are willing to pay for it, but saying you need wide-open sharpness because of group shots shows that you aren't shooting correctly. If you must you can compromise with ISO or use a tripod and low shutter speed, but aperture is not the tradeoff you make when shooting that stuff. Feel free to post a pro shot of a big group taken at 2.8 and prove us wrong. I think you'll have difficulty finding such a picture.
07-13-2010, 08:49 AM   #56
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QuoteOriginally posted by Eigengrau Quote
If you are taking group shots at 2.8, you are asking for trouble. 4.0 is even touchy, depending on the size of the group.

Asking for corner-to-corner sharpness is fine if you are willing to pay for it, but saying you need wide-open sharpness because of group shots shows that you aren't shooting correctly. If you must you can compromise with ISO or use a tripod and low shutter speed, but aperture is not the tradeoff you make when shooting that stuff. Feel free to post a pro shot of a big group taken at 2.8 and prove us wrong. I think you'll have difficulty finding such a picture.
Well, I don't get an extensive access to pro-photo agencies to get that point certainly. But I can put it differently, there are plenty of DOF calculators around, lets put the case of a 5DmkII

Focal length (mm) :16
Selected f-stop: F2.8
Subject distance:4 meters

Subject distance 4 m

Depth of field
Near limit 1.72 m
Far limit Infinity
Total Infinite

In front of subject 2.3 m
Behind subject Infinite

Hyperfocal distance 3.03 m
Circle of confusion 0.03 mm



Source : Online Depth of Field Calculator

Now you can contest the actual calculation, but I'm certainly not saying stupid things when saying that an ultrawide angle can be used at 2.8 for group photography. And their plenty of occasions where it ca be usefull, when for example in interior the light have been made very dim (candles) and iso streched to the max.
07-13-2010, 02:36 PM   #57
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Here's the problem. I don't think you are going to be using such a lens to shoot a group that is 4 meters away. If you look at the field of view given to you at 16mm on a 5DmkII, you would get about 96 degrees. Convert that angular distance to a linear distance when shooting a subject 4 meters away, and you would end up with an almost 7 meter swath being in the plane of focus with your subject. This is more stuff than you want in the frame for most portraits, even group ones. Supposing that you're shooting a large group 7 meters wide and 4 meters away, you'll have quite a time making sure that nobody on the edge looks like an alien because of the distortion of the lens.

I shoot large group shots at weddings pretty regularly (indoors and in low light), and frequently use a somewhat wide angle lens (17 or 18). First of all, I find that 5.6 is necessary to get everything as sharp as I'd like it. Secondly, I find that even these less extreme lengths can cause unwanted face distortions if you aren't careful. Shooting full-frame with a 16mm would be like shooting 8mm on a crop - not something you'd want to use on groups in the first place.

Sorry, but I can't help feeling like your situation is pretty hypothetical and not really related to things that most photographers are encountering regularly. The nature of group shots is that they need to be sharp, they can be taken at a place of the photographer's choosing, and they need to be flattering and technically ok. As well, a low shutter speed is often a possibility because people will hold still, and you can use a tripod if you need. All of these things say that a wide aperture is largely unnecessary.

For a more realistic comparison, I'd say that the situation that would call for such an extremely wide angle, you might be 1.5 meters from the subject. Then, you would have about 2 meters wide to work with. And, your focal plane is only about 1 meter at 2.8. Stopping down to 4.0 would be a good move, and 5.6 would probably be better. This is all assuming, of course, that this extreme wide angle isn't making your bride look like a beluga.

If you present a more realistic situation, or an example photo where this is useful, then I would happily consider it and change my opinion. But, as it is, I don't buy that 16mm/2.8 is a good idea for group shots, and in the few situations it might be, edge-to-edge sharpness is the least of your worries.
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