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03-20-2008, 12:04 AM   #1
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How Fast D-FA 50mm AF

Am thinking of getting 50mm (prime) for my K-10. I'm the photographer at out local dogpark, so lots of action. Was looking at the FA - 50mm for price reasons and all the praise for its' image qualities BUT got worried about a number of reviews that give it thumbs down on its' auto focus speed. In fact, some reviews said it wasn't recommended for action photography.
I rarely look through the viewfinder, just cup the K-10 in my hand and fire. Started shooting at the dogpark with a fuji point and shoot, got the K-10 around X-Mas '07 , with the 18 -55 kit lens - little bulky for one handed shooting. The smaller 55mm ( i think you call it a "prime" ) lens would be much more stable in my grip .
Any thoughts on the nimbleness of the D-FA 50mm 's auto focus ?


03-20-2008, 12:14 AM   #2
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Wow ... I wouldn't have bought a DSLR if i was going to shoot without looking through the viewfinder.

I think you will find that shooting with that sort of style will be less successful than your P&S camera you used to have.

How close to the action are you going to be though ... the 50mm is good for a lot of things ... but if the dogs are going to be running to and fro ... a faster zoom might be a better choice.
03-20-2008, 12:48 AM   #3
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The DA40 and the FA35 are faster than the FA50 and have a slightly wider field of view which might be helpful to catch the dogs without looking through the viewfinder.
03-20-2008, 02:18 AM   #4
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DA-40, some questions

Hmm... I do pretty good with my no look technique even with the k10. Don't get as many pics as many pics near or in focus or frame but what I do get is much better.
I looked at my latestest photos, and , sure enough, they're all 35mm or 24mm or 43 mm. So, maybe the da-40 is what I want.
By fast , I meant the auto focusing . Reviews say it's pretty good.
Here's a mindless question : in something like the 18mm - 55mm kit lenses, is the mm actually changing in some with auto ? It's not auto zooming is it ?
What auto focuses in a fixed MM lense ?
Why do people love the 50 mms so much?

Thanks for your replies and any upcoming thoughts,

Marty( voicelit) pics are at :

03-20-2008, 09:18 AM   #5
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I found my FA 35mm f/2.0 autofocused much faster than my 50mm, even though the 50mm was a stop faster aperture-wise. I shoot Canon now and my 85mm f/1.8 is significantly faster in autofocusing than any of my Pentax gear.

I think you should just stick with the kit lens for awhile and get used to it (and read up on some photography basics). To answer your 18-55mm question, that lens can be set to any focal length between 18mm and 55mm (inclusive). 18mm gives you a much wider "Field of View" than 55mm (I hate when people say 55mm is good for getting up close, you can get just as close with 18mm!)

By the questions you're asking, I don't think you are ready by be buying any prime lenses. So you have the kit lens? I'm confused..........Do you know what "focal length" is? Aperture? F-stop? Shutter speed? Learn these basics BEFORE buying any more gear (except for books, books are good to learn from )

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