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10-29-2014, 07:31 PM   #46
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This is a great read, comparing the Sigma 18-35 to the 31 ltd. Written by a guy who really knows Pentax equipment, almost everybody's equipment really. Reading this will give you a good handle on the 18-35 and the 31 ltd.
https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/270250-pent...m-f-1-8-a.html

10-30-2014, 03:22 PM   #47
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If you're going to spend $280 I say skip the 50 and get the tamron 17-50 2.8. It's PLENTY fast for any lighting. 1.8 is a pain in the ass to get in focus unless you are really comfortable with it. Plus 50 is way to tight for most things in the beginning. I should have listened to everyone on here and got the 35 instead. But now that I own the 17-50, I doubt the prime will ever go on my camera again other than just for the hell of it. The IQ of the tamron is more than adequate for a casual photographer like myself and the zoom is so much more freeing than a prime. I found shooting with a 50 to be way to restricting. I know it's because I'm new (6 months in) but I often didn't have room to back up enough to get the whole subject in the photo. Not saying it's a bad lens or FL but it's not very versatile. It's a tool that needs to be used in the right way to get the results you want. This is just my opinion but I think you'd be much happier with the tamron 17-50 2.8.
10-31-2014, 11:10 PM   #48
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Yes I have tried to check out that Tamron 17-50mm f/2.8 online but it is almost out of stock, if not full retail price, probably like $499 bucks so hmm.
I remember I did manager to try the 18-35mm SIgma lens back in GITEX 2014 last month here in Dubai, but the thing is that he mounted it in a lowest DLSR canon which is the SL1 so hands on quite sucked, I noticed right away the focusing issue! Probably I had it wide open at f/1.8. Here in the UAE there is only one sigma dealer in which I have to travel for total of 2 hours so figures, including that limited 31mm limited is being carried by one store only too! Jeez
The rarity of our gear is a bit tough but challenging! =)
11-01-2014, 01:24 AM   #49
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Great Link!

QuoteOriginally posted by normhead Quote
This is a great read, comparing the Sigma 18-35 to the 31 ltd. Written by a guy who really knows Pentax equipment, almost everybody's equipment really. Reading this will give you a good handle on the 18-35 and the 31 ltd.
https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/270250-pent...m-f-1-8-a.html
hey man thanks for the link, now the choice is getting even more harder wow!
Very good read indeed!
Am I right that this 31 Ltd is around 46-50mm in our APSC pentax cams?

11-01-2014, 02:45 AM   #50
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There are many good manual focus lenses out there for your budget, if you can be bothered with all that twisting the lens malarky.
11-01-2014, 04:29 AM   #51
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I actually meant a used 17-50. I got mine for $250 I believe, shipped from japan.
11-01-2014, 05:48 AM   #52
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QuoteOriginally posted by jcagara08 Quote
hey man thanks for the link, now the choice is getting even more harder wow!
Very good read indeed!
Am I right that this 31 Ltd is around 46-50mm in our APSC pentax cams?


The focal length is the focal length regardless of the body to which it is mounted. Because the aps-c sensor is smaller than the classic 35mm frame it sees a smaller portion of the focused image. The so called "crop factor" for the Pentax implementation is 1.6 if I'm not mistaken. To determine the full frame "equivalent" for purposes of estimating field of view, depth of field, etc. you multiply the focal length by the crop factor; 31 x 1.6 = 49.6 for the full frame equivalent. In other words, the 31mm on an aps-c camera will have approximately the same behavior as a 50mm lens on a "full frame" or 35mm film camera. That's a long-winded way of saying "yes."


The idea of "equivalence" seems to bring out strong reactions among some. I think it's probably useful for someone, such as myself, transitioning from the 35mm film world but in reality it's a crutch that needs to be discarded as soon as possible.


I'm not there and I still go through this exercise, but my goal is to learn the way the lenses behave on the body and not go through this chicanery to understand the appropriate choice for the image I want to record. In some ways it's like learning a language. In the beginning you have to mentally translate the words to and from your native tongue but eventually you become fluent and that intermediate step is no longer needed.
11-01-2014, 05:54 AM   #53
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I own the m50 1.7 and im in love with it

11-01-2014, 08:06 AM   #54
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QuoteOriginally posted by dakight Quote
The focal length is the focal length regardless of the body to which it is mounted. Because the aps-c sensor is smaller than the classic 35mm frame it sees a smaller portion of the focused image. The so called "crop factor" for the Pentax implementation is 1.6 if I'm not mistaken. To determine the full frame "equivalent" for purposes of estimating field of view, depth of field, etc. you multiply the focal length by the crop factor; 31 x 1.6 = 49.6 for the full frame equivalent. In other words, the 31mm on an aps-c camera will have approximately the same behavior as a 50mm lens on a "full frame" or 35mm film camera. That's a long-winded way of saying "yes."
Thanks for that explanation! I was unaware of this factor.
11-01-2014, 10:34 AM - 1 Like   #55
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QuoteOriginally posted by dakight Quote
The so called "crop factor" for the Pentax implementation is 1.6 if I'm not mistaken.
Canon 1.6, Pentax 1.5.
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