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11-09-2010, 03:57 AM   #46
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QuoteOriginally posted by twitch Quote
Ha, sorry about that But I think that is how it is between those lenses, the 15 is potentially the more spectaular due to its wider focal length, so it will have higher highs for landscape shots, but the 21 is the more versatile and would potentially be used in more situations.

Problem solved. I ordered both
I will give them both a good try and then sell the other one. I will sell it. Honestly.

11-09-2010, 05:00 AM   #47
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the famous LBA just struck.. again.. )

congrats, i wish i would be in your place)
11-09-2010, 06:55 AM   #48
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Can I use the FOV to calculate the loss of megapixels for cropping?

The FOV of the 21 (according to this calculation) is 80% of the 15. (68/86 ~ 80%).

Therefore, would a picture from the DA 15 with a 14 megapixel camera be cropped and look identical to a picture taken with the DA 21 with an 11.2 megapixel camera?

Taken from smc PENTAX DA 15mm F4 ED AL Limited - Official PENTAX Imaging Web Site and PENTAX DA Limited Wide-angle Lens for Digital SLRs and Compacts: smc PENTAX DA 21mm F3.2 AL Limited.
11-09-2010, 07:12 AM   #49
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You are going to get both. You know that, right? I got the 15 first, because - well - I read that it would control my mind. It does, even though it probably isn't as useful as the 21. The Limiteds are addicting in a low fat kind of way and make my 16-45 look kind of rotund. So even though I knew that I would only get one (i.e., the 15), the 21 is next on the list. Resistance is futile.

11-09-2010, 07:40 AM   #50
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QuoteOriginally posted by MikeW Quote
You are going to get both. You know that, right? I got the 15 first, because - well - I read that it would control my mind. It does, even though it probably isn't as useful as the 21. The Limiteds are addicting in a low fat kind of way and make my 16-45 look kind of rotund. So even though I knew that I would only get one (i.e., the 15), the 21 is next on the list. Resistance is futile.
Yes I will but not for another year - finances dictate. So my question remains... how much does one need to crop the 15 to get the FOV of the 21?
11-09-2010, 10:29 AM   #51
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I would really like to see the same picture from the 15 and 21

You guys with both: Please please please please!!!!
11-09-2010, 02:46 PM   #52
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QuoteOriginally posted by Noidea Quote
Problem solved. I ordered both
I will give them both a good try and then sell the other one. I will sell it. Honestly.
I almost believe you, but then I own them both know how hard it would be to part with either.

Seriously, if you are going to sell one I'd advise giving it at least a couple of months before deciding which to keep, it took me a while to figure out the DA21 and I'm still a long way from figuring out how to get the best out of my DA15.

Congratulations though, and enjoy!
11-09-2010, 02:50 PM   #53
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Thanks

11-09-2010, 03:42 PM   #54
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QuoteOriginally posted by paperbag846 Quote
Can I use the FOV to calculate the loss of megapixels for cropping?

The FOV of the 21 (according to this calculation) is 80% of the 15. (68/86 ~ 80%).

Therefore, would a picture from the DA 15 with a 14 megapixel camera be cropped and look identical to a picture taken with the DA 21 with an 11.2 megapixel camera?

Taken from smc PENTAX DA 15mm F4 ED AL Limited - Official PENTAX Imaging Web Site and PENTAX DA Limited Wide-angle Lens for Digital SLRs and Compacts: smc PENTAX DA 21mm F3.2 AL Limited.
this is an interesting question but i think you would have to square the 80%. So it would have 64% of the MP's. Because if you had a 35mm and 70mm and took the same picture it would be half as wide and half as tall (leaving you with 25% of the original picture).

So the 'just crop the picture' can work but you are significantly decreasing the quality. Although if you only look at your pictures on the computer it's fine. But that was one of biggest reasons I got a new camera. I want to be able to have pictures that I can print bigger than 8x10.
11-09-2010, 04:20 PM   #55
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Thanks for the reply, your math makes sense to me. I thought that an 80% reduction just didn't sound right.

Well I went and ordered the DA 15 anyways . I knew that if I had ordered the 21, I always would have wondered about the 15. Now I have my wide end covered, and the ability to crop for non-crucial applications.

I have a 28mm to tide me over, and in all honesty, while they are both great, the DA 15 just looks more...special. Time will tell! The good news is that I can always buy the 21 if I find I have made a horrible mistake (and then, I'll throw my credit card in a lake ).
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