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03-18-2013, 05:40 PM   #16
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QuoteOriginally posted by cali92rs Quote
You are correct, I meant new Pentax lenses...
It is a bit odd. They made the FA 43mm which is exactly 'normal', the only one I'm aware of. Maybe someone who has been around longer than me can remember if Pentax ever used that in their marketing.

But for DA we have no equivalent which should have been a 28mm or maybe a 29mm. Change in marketing or design philosophy along the way maybe?

03-18-2013, 05:44 PM   #17
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The math is nice but I don't see the world that way. On APS-C, 28mm feels wide and I start looking for subjects in a wide angle frame of mind. If I use it for a while, I see better at its focal length but never quite give up on the wide idea. My FA 35/2 feels much more like a normal. I suggest that others figure out whether they really like a focal length before committing to someone else's idea of normal. The kit lens is good for that purpose.

The F28/2.8 is not a lot bigger than a pancake design, and there's room for a lens between 21 and 35. Unfortunately Pentax has not decided to fill that gap.
03-18-2013, 05:50 PM   #18
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The FA31 is not a bad stop gap measure while we are waiting for a true normal
03-18-2013, 05:56 PM   #19
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QuoteOriginally posted by kristaps Quote
I'm Just wondering - sensor diagonal of the camera is 28.4mm. Then why the current Pentax lineup of lens has the compact 43mm and 40mm limiteds which are on the long side and the 21mm limited which is on the wide side, but nothing similar in between?Basically I'd like to find a normal perspective (say, between 24mm and 35mm) prime lens that's smaller and faster than the kit zoom.
FA 31.

With its built-in hood,
it's just 1mm longer than the kit zoom without a hood,
and 3mm narrower.

03-18-2013, 06:19 PM   #20
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QuoteOriginally posted by lytrytyr Quote
FA 31.

With its built-in hood,
it's just 1mm longer than the kit zoom without a hood,
and 3mm narrower.
And, contrary to the kit zoom [that I got] can actually take sharp pictures with contrast...

(yes, the kit zoom on my K-01 was a dud....didn't realize that for months as I stuck the 31 on it from the first second it came in the house)
03-18-2013, 07:43 PM   #21
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I've been using the M 28 f2.8 as a "normal" on my K-30 and K-01 and for scenes from 8 to 20 feet distant it offers a great perspective. Minimal vignetting means it is perfect for stitching as well. It also has very good edge to edge sharpness. The FA 31 should do the job just as well. Traditional 50-58mm lenses on 35mm SLRs were compromises to allow more body depth for the mirror. Many of the compact rangefinders used 45 mm.
03-18-2013, 09:27 PM   #22
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QuoteOriginally posted by Professor Batty Quote
Traditional 50-58mm lenses on 35mm SLRs were compromises to allow more body depth for the mirror.
I have never felt that 50mm on 35mm film was normal - I've always felt that it was a short telephoto. To the degree that, when I first began shooting, I really couldn't figure out how to use my 50mm, because I could understand the perspective. I was much more at home with my 28mm. Of course this was wide, but I felt that it mirrored the way I saw the world. I'm sure I would have enjoyed a 35mm even more, but I didn't own one.
03-18-2013, 09:56 PM   #23
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I'm a fan of the 40mm equivalent (or thereabouts) FOV as well. It was a popular focal length on 35mm fixed lens cameras before zooms started to enter the market. If your eye for images has been strongly trained by using 50mm 'normal' lens on 35mm, the 35mm on crop sensor will suit your style and you may regard this as the 'new normal'. If your eye has been developed on fixed lens cameras (as mine seems to have been), then 28mm on crop sensor is of greater appeal as it equates to 42mm on film. There's no right or wrong answer - it's a matter of personal preferences and shooting style. If you go back to screw mount days, the 'normal' lens was once 55mm, and then the view of 'normal' came down to 50mm over the years. As others have said, true normal on 35mm is a 43mm FL lens eg so it could be argued that Pentax was the only company that ever built a lens for the purist, ie the FA43.

03-19-2013, 01:30 AM   #24
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If I remember rightly, the FA 43mm f1.9 was the first Limited lens. Its focal length caused some eyebrows to be raised in the photographic press, but it was chosen by Pentax precisely because that was the diagonal of a 35mm film frame, and thus the most "normal" lens ever to be issued at the time.
03-19-2013, 01:50 AM   #25
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QuoteOriginally posted by Professor Batty Quote
I've been using the M 28 f2.8 as a "normal" on my K-30 and K-01 and for scenes from 8 to 20 feet distant it offers a great perspective. Minimal vignetting means it is perfect for stitching as well. It also has very good edge to edge sharpness.
Given that you're using a full-frame lens on crop-sensor cameras, vignetting should be non-existent rarther than 'minimal' ... The edge sharpness should be good as you're not using the edges of the lens ...
03-19-2013, 06:19 AM   #26
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QuoteOriginally posted by DaveHolmes Quote
Given that you're using a full-frame lens on crop-sensor cameras, vignetting should be non-existent rather than 'minimal' ... The edge sharpness should be good as you're not using the edges of the lens ...
By vignetting I mean any uneven illumination across the frame. Ordinarily it is isn't much of an issue for most images, but even the smallest amount in a stitched panoramic will show up- usually in the sky. Edge sharpness is still a factor in crop-sensor lenses, but again only under certain circumstances- especially wide open. All those little annoyances are eliminated with a good 28.
03-19-2013, 06:57 AM   #27
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QuoteOriginally posted by Professor Batty Quote
All those little annoyances are eliminated with a good 28.
And luckily most (if not all) of Pentax's 28's are pretty good! :-)
03-19-2013, 07:02 AM - 1 Like   #28
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QuoteOriginally posted by southlander Quote
I'm a fan of the 40mm equivalent (or thereabouts) FOV as well. It was a popular focal length on 35mm fixed lens cameras before zooms started to enter the market. If your eye for images has been strongly trained by using 50mm 'normal' lens on 35mm, the 35mm on crop sensor will suit your style and you may regard this as the 'new normal'. If your eye has been developed on fixed lens cameras (as mine seems to have been), then 28mm on crop sensor is of greater appeal as it equates to 42mm on film. There's no right or wrong answer - it's a matter of personal preferences and shooting style. If you go back to screw mount days, the 'normal' lens was once 55mm, and then the view of 'normal' came down to 50mm over the years. As others have said, true normal on 35mm is a 43mm FL lens eg so it could be argued that Pentax was the only company that ever built a lens for the purist, ie the FA43.
Sorry to contradict you, but if you read my other comment you will see that associating FL to normal view or not is not correct but instead you may think of the AoV that outcomes from that FL plus sensor size.

In 135 format (24x36mm), the diagonal of the sensor has 43mm. so, using a FL 43mm assures an image with normal perspective (does not compress the edges or expand the center) but never a normal view.
Normal view is associated with the angle of view of the human eye, which is about 40 (20 to each side of our nose). After those 20, the eyes ability to detect detail / color and contrast are drastically diminished BUT this may vary from eye to eye. So normal view is kind of subjective or at least, depends of each pair of eyes.

All this said, you are down right. Depends on what each of us is used to see as normal. But using a FL that equals the diagonal of a sensor should not be associated with view, but perspective.

regards,
Francisco
03-20-2013, 01:37 AM   #29
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QuoteOriginally posted by maxfield_photo Quote
it's the flange distance, not the sensor size I think that determines what focal length lends itself best to "pancakization".
How do you explain the DA 21mm limited then? It's the same size as FA 43mm.

QuoteOriginally posted by lytrytyr Quote
FA 31. With its built-in hood, it's just 1mm longer than the kit zoom without a hood, and 3mm narrower.
I am aware of the FA 31mm, but it's out of my budget, and quite big too. The DA40mm or DA21mm limiteds would currently be about my budget, the FA43mm would already be a stretch.

Anyway, thanks to everyone for the suggestions! When reviewing the photos I've taken so far I see that 28-35mm range is the most often used. By the way, I cannot really say anything bad about the image quality I get from my WR 18-55 kit, maybe I just have not outgrown it yet the reason I want a prime is to have something faster and smaller.

I am currently trying to buy an old Pentax-A 28mm f2.8 on ebay (these are fairly common and inexpensive), just to try taking pictures with a fixed focal lens. But eventually autofocus would be nice. So I'll keep looking for some of the suggestions mentioned, like FA 35mm f2.0.
03-20-2013, 02:11 AM - 1 Like   #30
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QuoteOriginally posted by carrrlangas Quote
Sorry to contradict you, but if you read my other comment you will see that associating FL to normal view or not is not correct but instead you may think of the AoV that outcomes from that FL plus sensor size.

In 135 format (24x36mm), the diagonal of the sensor has 43mm. so, using a FL 43mm assures an image with normal perspective (does not compress the edges or expand the center) but never a normal view.
Normal view is associated with the angle of view of the human eye, which is about 40 (20 to each side of our nose). After those 20, the eyes ability to detect detail / color and contrast are drastically diminished BUT this may vary from eye to eye. So normal view is kind of subjective or at least, depends of each pair of eyes.

All this said, you are down right. Depends on what each of us is used to see as normal. But using a FL that equals the diagonal of a sensor should not be associated with view, but perspective.

regards,
Francisco
Hhhmmm - there have been long, laborious threads here and on dpreview demonstrating that neither focal length nor angle or view are related to perspective, strictly defined. Perspective depends entirely on the relative physical positioning of you (the photographer) and the various objects in front of you; that will not change no matter what lens you put on the front of the camera. (Distortion is something different.)
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