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07-07-2010, 01:00 AM   #31
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QuoteOriginally posted by ogl Quote
How good the samples...
AT-X 16-28 F2.8 PRO FXbǕ̎_
Outstanding.
I just had a look, the maximal aperture used is F4, that a bit disappointing.

I would like to see a sample at F2.8 and 16mm where corner sharpness and vingetting is the most challenging.

The pictures are ok, but I didn't see anything breathtaking.

07-07-2010, 02:45 AM   #32
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QuoteOriginally posted by ghelary Quote
I just had a look, the maximal aperture used is F4, that a bit disappointing.

I would like to see a sample at F2.8 and 16mm where corner sharpness and vingetting is the most challenging.

The pictures are ok, but I didn't see anything breathtaking.
If you shoot with FF camera with 21-24 MP at 16-28 mm, you can see how poor corner's sharpness of wide-angles lenses till f8. Except, just several very expensive lenses.
This lens easy covers 24 MP sensor with good sharpness across the frame at f4.
To shoot landscapes/architecture at f2.8 is rather strange pastime...IMO.
07-07-2010, 03:03 AM   #33
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weather sealing...

weather sealing is a good thing ! Because of this Pentax is so good for weddings... : Fotograf la nunta - OWNED | 220.ro

07-07-2010, 03:20 AM   #34
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QuoteOriginally posted by liviul Quote
weather sealing is a good thing ! Because of this Pentax is so good for weddings... : Fotograf la nunta - OWNED | 220.ro

this made me really laugh hard

07-07-2010, 03:35 AM   #35
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QuoteOriginally posted by ogl Quote
If you shoot with FF camera with 21-24 MP at 16-28 mm, you can see how poor corner's sharpness of wide-angles lenses till f8. Except, just several very expensive lenses.
This lens easy covers 24 MP sensor with good sharpness across the frame at f4.
To shoot landscapes/architecture at f2.8 is rather strange pastime...IMO.
I was more thinking about interior scenes where you may want to have everything in frame and sharp (and don't have the space to take a step back)

I have looked at F8 picture (the beach in particular) and have seen very significant differences between borders and center.

The thing is, if you sell a lens that open at F2.8, one expect it to be usable at F2.8. F2.8 wideangle FF zooms are hudge beasts, why shall I buy it if I need to use a lens at F8 ? A F4 or F5.6 lens would be much smaller.

I do own some Pentax high quality primes and prefer them to zooms because of the size, not the price. If I were to buy a FF system, I would consider this lens only on respect to my usage and its performances. Even if it's advertised as a 2.8 16-28 lens, if it's performing well only between 18-24 and starting F4, then it can be compared with F4 lenses. And if I use wideangles at F8 only, why shall I care about this zoom ? There are cheaper, lighter, alternatives that are valid at F8 out there.
07-07-2010, 05:44 AM   #36
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QuoteOriginally posted by axl Quote
this made me really laugh hard
laugh or not, but I really spare this photographer. Could you imagine what feelings he had the moment he found himself in a pool ?
07-07-2010, 08:26 AM   #37
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I've been noticing that some Tokina APS-C lenses in multiple mounts, the 50-135 f/2.8 in particular, are either out of stock or have been discontinued. Maybe they are shifting their strategy to offer full frame lenses because they see a market in offering cheaper alternatives to the full frame pro glass that Nikon, Canon and Sony offer. Since the best Nikon zooms cost $1,800+ I could see why they might think that.

07-07-2010, 08:45 AM   #38
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QuoteOriginally posted by ghelary Quote
I was more thinking about interior scenes where you may want to have everything in frame and sharp (and don't have the space to take a step back)

I have looked at F8 picture (the beach in particular) and have seen very significant differences between borders and center.

The thing is, if you sell a lens that open at F2.8, one expect it to be usable at F2.8. F2.8 wideangle FF zooms are hudge beasts, why shall I buy it if I need to use a lens at F8 ? A F4 or F5.6 lens would be much smaller.

I do own some Pentax high quality primes and prefer them to zooms because of the size, not the price. If I were to buy a FF system, I would consider this lens only on respect to my usage and its performances. Even if it's advertised as a 2.8 16-28 lens, if it's performing well only between 18-24 and starting F4, then it can be compared with F4 lenses. And if I use wideangles at F8 only, why shall I care about this zoom ? There are cheaper, lighter, alternatives that are valid at F8 out there.
The image quality shown in the sample gallery is excellent. To expect an f/2.8 wide angle zoom to be as sharp in the corners as in the center is not reasonable. After all, f/2.8 is never a good choice if you want to get everything sharp.
07-08-2010, 03:54 PM   #39
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QuoteOriginally posted by matthis Quote
The image quality shown in the sample gallery is excellent. To expect an f/2.8 wide angle zoom to be as sharp in the corners as in the center is not reasonable. After all, f/2.8 is never a good choice if you want to get everything sharp.
You should try some Olympus glass. The 14-35 is razor sharp from f/2 through f/5.6. There are a lot of primes that are very, very sharp at f/2.8.
07-08-2010, 04:05 PM   #40
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QuoteOriginally posted by liviul Quote
weather sealing is a good thing ! Because of this Pentax is so good for weddings... : Fotograf la nunta - OWNED | 220.ro

Great video - and yes, I just appreciated the Pentax weather sealing at a recent wedding. It was a downpour at times, and we had the wedding party tucked away under awnings so they wouldn't get soaked, but of course to get the shots my wife and I had to get a bit soggy. Nice chance to brag that I wasn't worried about the camera!
07-09-2010, 03:44 AM   #41
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QuoteOriginally posted by matthis Quote
The image quality shown in the sample gallery is excellent. To expect an f/2.8 wide angle zoom to be as sharp in the corners as in the center is not reasonable. After all, f/2.8 is never a good choice if you want to get everything sharp.
See : Nikkor AF-S 14-24mm f/2.8G ED (FX) - Review / Test Report

Yes, a lens can be sharp from border to border at 2.8.

Basically I see no point in shooting with an extreme wideangle at F2.8 if borders are weak. Such a setting is not usable for portraiture and dept of field is already big at 2.8 because of the focal lens.

And I do maintain that I'm not impressed by border uality at F8. Which is in the sweet spot of about any lens.
07-09-2010, 04:14 AM   #42
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QuoteOriginally posted by ghelary Quote
See : Nikkor AF-S 14-24mm f/2.8G ED (FX) - Review / Test Report
Yes, a lens can be sharp from border to border at 2.8.
Suspecting you are confusing borders with corners, I see nothing in the Photozone test supporting your claim.
BTW, the Photozone figures give merely a hint to the quality of a lens. The relevance of MTF50 measurings is rather limited.

QuoteOriginally posted by ghelary Quote
Basically I see no point in shooting with an extreme wideangle at F2.8 if borders are weak. Such a setting is not usable for portraiture and dept of field is already big at 2.8 because of the focal lens.
If you don't see the point... well there will be others who will.
I think you are lacking experience.

QuoteOriginally posted by Winder Quote
You should try some Olympus glass. The 14-35 is razor sharp from f/2 through f/5.6. There are a lot of primes that are very, very sharp at f/2.8.
Comparing a 28mm equivalent to a 16mm lens is really useful.
BTW, I have not seen any 24 MP pictures with a 4/3 camera.
07-09-2010, 05:52 AM   #43
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QuoteOriginally posted by matthis Quote
Suspecting you are confusing borders with corners, I see nothing in the Photozone test supporting your claim.
BTW, the Photozone figures give merely a hint to the quality of a lens. The relevance of MTF50 measurings is rather limited.


If you don't see the point... well there will be others who will.
I think you are lacking experience.


Comparing a 28mm equivalent to a 16mm lens is really useful.
BTW, I have not seen any 24 MP pictures with a 4/3 camera.
QuoteQuote:
"At 14 and 18 mm the borders and extreme corners follow only slightly behind with very good resolution, at 14 mm just crossing the mark to excellent figures at some aperture values. At 24 mm, the border and extreme corner resolution falls a bit behind, but can recover to very good figures stopped down to f/5.6 or f/8. "
I think its written quite clearly in English. Good in the corners (even if exceptional in the center) and Photozone, whatever are the flaws of their test is maybe the most respected ressources of the Internet when it comes to

There are some classes of lenses that have been stopped to be produced because of specific flaws that impaired their use. Typically mirror telelenses have been stopped mostly beacause of the "donut bokeh".

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.

Now, regarding experience, I think you shall be refraining your comments, I do have some experience, I hang out quite with some pro photographers who have been educating me regarding photography. And, living in Paris, I can attend to expostion of major artists on a regular basis (seeing photographies from Evans, Depardon or lately Mimo Jodice do a lot to cool your head down) I certainly do not consider me a "mature" photographer, but owning and using my share of FA and DA ldt, a full 6x7 system (including the 45mmF4) and some few other things, so all in all I consider myself quite educated regarding the artistic and techncial sides.

That is saying that I don't have anything against this lens. Maybe further field and lab will show a good performer. And I do know that an ultrawide lens is a hudge technical challenge. That been said, in that class, Nikon did set the benchmark and Tokina will be fatally compaired to it, producing an ultrawide, ultrafast, FF lens is a disclamer for pro quality and therefore whall be compared to the Nikon.

Anyway, ultrawide is not my taste and I feel that 28mm (FF) is plenty enough for when wideangle is needed. I can go for a long time on why 24mm and wider lenses are producing at the moment a "in your face" photography that I don't like with photo-reporters and provide examples and arguments, but that's not the subject of this thread. Which is about the expected qualities of a specific lens.
07-10-2010, 01:51 AM   #44
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QuoteOriginally posted by ghelary Quote
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.
Aunt Sally will be displeased anyway, if she stands at the extreme side, even if the performance of the lens is sound, because geometry of an ultrawide lens will morph her features in a very evident way.
07-10-2010, 07:07 AM   #45
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The Right Tool for The Job

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.


QuoteOriginally posted by eurostar Quote
Aunt Sally will be displeased anyway, if she stands at the extreme side, even if the performance of the lens is sound, because geometry of an ultrawide lens will morph her features in a very evident way.
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