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10-20-2008, 09:15 PM   #16
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morfic I am not positive and I am not sure where I read before. I will try to hunt up the information.

The K version does usually bring a higher price more than the M version. The nice thing about the A version is of course the ease of use on a modern body.

10-21-2008, 02:10 AM   #17
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I have the M version of this lens, but haven't had it long enough to form much of an opinion. I'm also not a very good photographer so my opinion wouldn't be worth much anyway.

Here's a few crops, I tried to focus on the red no trespassing sign. The aperture is f/2 on the furthest left crop, and increases by one stop up to f/16 on the far right. Some of the crops below are not necessarily on the focal plane. You'll probably have to right-click and view the image in a new window then zoom in to view it at 100%. The images are really wide. The first two should show sharpness, the second two CA.




10-21-2008, 09:51 AM   #18
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I'd love to get my hands on the 'A' version, but I doubt I'd have the funds. Last week I picked up the Vivitar 28mm f/2 from the marketplace. It's no larger than an f/2.8, which is great, as one of the positive points about primes is that they're meant to be small.

I've still to test it carefully, but so far I can say that it's plenty sharp wide open to be usable, which is the whole point of having an f/2 lens, no? Of course, it has no contacts, but it can be shot in Av at f/2 so that's not a huge concern.
10-21-2008, 09:58 AM   #19
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One thing to keep in mind is that wide lenses are not going to be that great wide open. A 200mm might be great wide open. A 28mm less so. Most people will stop a wide lens down while shooting.

So, some may ask why all the fuss over a f/2 wide lens then? Most lenses have a nice "sweet spot" several clicks down from the maximum aperture. If you take an f/4 lens then it might be sharp two clicks down at f/8. Take the same focal length but this time a f/2 lens and two clicks down you might be getting good performance at f/4. If you are hand holding in poor light this can really make a difference. It might mean not setting the ISO to a noisy 800 etc.

10-21-2008, 10:36 AM   #20
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Max I fully agree.

My opening statement I said the A28 f2 is a great low light lens. The nice thing is it is really good from f2.8.
10-21-2008, 10:45 AM   #21
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Further to Max's comment, the other benefit is that when focussing in low light you are looking through an f/2 aperture, which is twice as bright as an f/2.8. This makes focussing easier as you can better see your subjects. Not a big deal in daylight, big deal in low light (indoors, dusk, dawn, etc.).
10-21-2008, 09:01 PM   #22
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QuoteOriginally posted by Photomaximum Quote
One thing to keep in mind is that wide lenses are not going to be that great wide open. A 200mm might be great wide open. A 28mm less so. Most people will stop a wide lens down while shooting.

So, some may ask why all the fuss over a f/2 wide lens then? Most lenses have a nice "sweet spot" several clicks down from the maximum aperture. If you take an f/4 lens then it might be sharp two clicks down at f/8. Take the same focal length but this time a f/2 lens and two clicks down you might be getting good performance at f/4. If you are hand holding in poor light this can really make a difference. It might mean not setting the ISO to a noisy 800 etc.
I think this is a pretty glaring misconception. If anything, my worst lenses wide open are in the normal-short tele range.

I would not hesitate to use the DA21, FA*24, A28/2.8, or FA31 wide open if needed, which is more often than you might expect. They're all much better than the FA43 or 50/1.4 in this respect.
10-21-2008, 09:23 PM   #23
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Well, it depends on what you are looking for. Wide angle lenses have the perception of greater depth of field. Middle range and longer lenses less so. Users will user a longer lens or a middle range lens wide open to achieve a shallow depth of field: the sharp subject against a blurry soft background.

For the most part wide angle users are looking for a great depth in their shots. If you look at all the chatter in the many, many photography forums the big debate with wide lenses is image quality and how the centers match up against the corners. There is a lot of frustration over this issue. The better lenses like the 21mm Distagon 2.8 have great IQ in the center and the corners at f4. There are very, very few wide lenses that can match this achievement. That is the reason that lenses of this caliber cost $2000 -$3000 used! Usually wide lens users will stop down the lens aperture to achieve the best results. The better lenses, in many cases with faster apertures, will not need to be stopped down as far to achieve the center and corner IQ that users are looking for.

Your experience and style may differ but generally I stand by what I say and in my view I have not created a "glaring misconception" here.

10-22-2008, 01:09 PM   #24
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Thanks for the reply; I agree with you about their applications in general, and I was mostly hinting at the argument that wide angles are bad wide open. Of course, you'd expect to generally stop down for the type of shots you normally take with wides.

My main point is that all of my wides (from 14-31mm) are more usable wide open than either my 43 and 50mm lenses, and surely many telephotos, usage aside. Stopping wides down is mostly required for depth of field, and little else. They of course improve, but so do many normal and teles except the few $1000+ ones around.

QuoteOriginally posted by Photomaximum Quote
Well, it depends on what you are looking for. Wide angle lenses have the perception of greater depth of field. Middle range and longer lenses less so. Users will user a longer lens or a middle range lens wide open to achieve a shallow depth of field: the sharp subject against a blurry soft background.

For the most part wide angle users are looking for a great depth in their shots. If you look at all the chatter in the many, many photography forums the big debate with wide lenses is image quality and how the centers match up against the corners. There is a lot of frustration over this issue. The better lenses like the 21mm Distagon 2.8 have great IQ in the center and the corners at f4. There are very, very few wide lenses that can match this achievement. That is the reason that lenses of this caliber cost $2000 -$3000 used! Usually wide lens users will stop down the lens aperture to achieve the best results. The better lenses, in many cases with faster apertures, will not need to be stopped down as far to achieve the center and corner IQ that users are looking for.

Your experience and style may differ but generally I stand by what I say and in my view I have not created a "glaring misconception" here.
10-22-2008, 01:25 PM   #25
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I see some great shots with wide lenses wide open. Sometimes it does isolate the subject against the background. Its nice to have a quality wide lens that is capable of being shot near wide open when you need it.

I use wides a lot and generally work hard to get them to perform well. Its not always easy. You are fighting against distortion and performance across the center and corners. I have lost count with how wide lenses I have used over the years. I am very interested that Zeis has announced that they will be rereleasing the famous 21/2.8 Distagon in the EF mount (maybe Pentax as well). This is known to the be best wide lens ever made. All wide lenses are compared to this heavy monster.
10-22-2008, 06:47 PM   #26
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QuoteOriginally posted by Photomaximum Quote
Well, it depends on what you are looking for. Wide angle lenses have the perception of greater depth of field. Middle range and longer lenses less so. Users will user a longer lens or a middle range lens wide open to achieve a shallow depth of field: the sharp subject against a blurry soft background.

For the most part wide angle users are looking for a great depth in their shots. If you look at all the chatter in the many, many photography forums the big debate with wide lenses is image quality and how the centers match up against the corners. There is a lot of frustration over this issue. The better lenses like the 21mm Distagon 2.8 have great IQ in the center and the corners at f4. There are very, very few wide lenses that can match this achievement. That is the reason that lenses of this caliber cost $2000 -$3000 used! Usually wide lens users will stop down the lens aperture to achieve the best results. The better lenses, in many cases with faster apertures, will not need to be stopped down as far to achieve the center and corner IQ that users are looking for.

Your experience and style may differ but generally I stand by what I say and in my view I have not created a "glaring misconception" here.
If you wish to show a person in their environment, you may appreciate a lens that is sharp wide open, or sharp enough to achieve the look of a person in focus with a soft out of focus background.

https://www.pentaxforums.com/forums/333889-post17.html

Look at his woman in red shot, tell me this does not look better at f/2 than if you would have had a 2.8 that you need to stop down to f/4-f/5.6 to get enough resolution.

I agree with you when i had a CZ Distagon 28/2.8 that i mostly used stopped down for it's amazing resolution. It is however not the only use of a wideangle lens, especially if we consider it's a 42mm equiv field of view and thus more normal than wide to begin with.

It's this shot that made me post this thread in the first place
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