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07-05-2016, 03:05 PM   #31
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QuoteOriginally posted by Paul the Sunman Quote
Do you have any wide-to-mid primes, f/2.8 or faster? If not, and if you often shoot indoors or at night, the Sigma 17-50 may be useful. Personally, I'm happy enough to rely on my primes and/or flash.

I think you'll be very happy with the 16-85.
No, its actually my first time buying a camera and I ordered a DA 35 along with the 16-85. The price drop on Sigma is tempting, but I guess I could play with my new camera +lenses to figure out what I truly want personally. Thank you. And, by the way, isn't f/2.8 meaning the amount of light coming into the lens? smaller number meaning more lights coming in? I am kinda confused about why people would refer amount of light coming in as it's fast or slow...

07-05-2016, 03:38 PM   #32
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Have not read through all the replies above, but I'm sure they've pointed that: 1) APS-C bodies and equivalent range zooms & SFL lenses are smaller & lighter; 2) frame rates and write speeds on APS-C are faster, and download to computer time is shorter; 3) telephotos with equivalent on-sensor image size are MUCH smaller/lighter; 4) FF compatible wide range zooms are few and generally have less range, for example, my standard travel zoom for the K3 is a Sigma 18~250mm, which translates to 27~375mm FF equivalent; the only FF compatible zoom with near comparable range is the Tamron 28~300mm, so APS-C has a little extra at each end, but there's a new 18~300mm for APS-C (27~450mm equivalent); 4) there are more in-production APS-C lenses than FF compatible lenses, for example, for APS-C there are multiple fish-eye lenses (zoom, SFL and even a circular); but there's only one FF fish-eye for K-mount in production (Sigma). I'm not ready to give up my K3 (or k5) as yet.

Last edited by WPRESTO; 07-06-2016 at 05:41 AM.
07-05-2016, 03:51 PM - 1 Like   #33
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QuoteOriginally posted by talkskiwon Quote
And, by the way, isn't f/2.8 meaning the amount of light coming into the lens? smaller number meaning more lights coming in? I am kinda confused about why people would refer amount of light coming in as it's fast or slow...
When you have a lens with a wider aperture (lower f number) it allows in more light, as you say (unless stopped down of course), which means you need a shorter exposure time. Hence it is "faster".
07-05-2016, 04:28 PM   #34
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As was pointed out in another post there is a little leapfrog here when you compare a recently introduced camera to a camera with three year old technology. Some of that three year old technology in the k3, like autofocus tracking, was not even state of the art three years ago. There will likely always be some ISO/Noise issues that will favor the FF over the aps-c but a new APS-C camera introduced in a few months will likely surpass the K1 in focus speed, tracking, etc. The new camera will likely have better noise/iso characteristics than the K3. You could play leapfrog for a long time. If I plan to go out to photograph wildlife, unless I have a 600 or 800 prime lens for a full frame camera I will chose an APS-c over a fullframe camera because I get more pixels on the image from the same distance. Since most of my photography has migrated to wildlife after I moved two years ago, I will wait and see what the K3 replacement looks like. I really want a camera with better focus speed and tracking than my K3. I also do some interior building photography for a historical society and a full frame would be nice for that work but most of that work just gets put a a web site and then the advantages of a full frame get diminished by a lot. First I need an aps-c replacement for my K3 for the bulk of my time with a camera photographing wildlife.

07-05-2016, 04:58 PM   #35
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QuoteOriginally posted by Paul the Sunman Quote
When you have a lens with a wider aperture (lower f number) it allows in more light, as you say (unless stopped down of course), which means you need a shorter exposure time. Hence it is "faster".
Gracias
07-05-2016, 07:49 PM - 1 Like   #36
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QuoteOriginally posted by BigMackCam Quote
I agree completely. Full frame isn't better than APS-C - just different, and depending on your requirements one may be more suitable than the other in a certain situations...
Different...that is exactly right. Of course I am K1 biased but I was pretty happy with my K5IIs and would not be disappointed if it was still my prime camera.
My main point is that the better AF and ISO may be a worthwhile feature for many. According to DPR the AF is not all that good...I certainly have not found that to be the case at all. It is excellent, the best on any Pentax to date.

What is most important to remember in this conversation is that we do have a lot of fantastic Pentax choices, and at very affordable prices.

Regards!
07-05-2016, 11:31 PM   #37
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QuoteOriginally posted by Rupert Quote
What is most important to remember in this conversation is that we do have a lot of fantastic Pentax choices, and at very affordable prices.
What is also important is that Ricoh show signs of relentless development of both FF and APS-C equipment. They haven't picked a side in a competition - even while all the news about the K-1 was still active, they announced the D-70 and a lens with a new KAF4 mount.
07-06-2016, 03:48 AM   #38
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250 mm x 1.5 crop factor equals 375mm, not 425mm.

07-06-2016, 04:33 AM   #39
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QuoteOriginally posted by Barry Pearson Quote
What is also important is that Ricoh show signs of relentless development of both FF and APS-C equipment.
Ricoh has been good for Pentax and for us. So unlike Hoya that almost ruined Pentax.
07-06-2016, 05:39 AM   #40
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QuoteOriginally posted by henryk Quote
250 mm x 1.5 crop factor equals 375mm, not 425mm.
Correct. Realized my error about an hour later while out driving, but forgot to make the correction when I got home four hours later. A little early onset Alzheimer's can relieve you of so many worries. I will go make the correction now, before I forget.

Now please excuse me, I think there was something I needed to do, Something... Something.... I just know there was something.
07-06-2016, 02:50 PM   #41
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QuoteOriginally posted by starbase218 Quote
OTOH the differences in size and weight between a K-1 with a 24-70/4 and a K-3 with a 16-50/2.8 would be smaller, if that 24-70/4 existed. This is arguably a more "equivalent" setup in terms of capabilities. The lenses would probably be about the same size/weight. The K-1 is still quite a bit heavier than the K-3, but there are fullframe DSLRs out there that are actually lighter than the K-3. So I think you could get yourself a fullframe setup with f/4 lenses, enjoy the fullframe advantages, and still have about the same weight to carry around. (currently, this is not the case with Pentax though)


Sort of, sort of not.


The 24-70 F4 is still F4 and lets F4 amount of light in. The 16-50 is still F2.8 and lets 2.8 amount of light in.


The depth of field difference is less than 2 inches at 10 feet at F2.8 vs F4. If that matters at all. (APS-c can't touch Canon's 85mm 1.2 on FF, but then I don't see a lot of people around here shooting a Canon 85mm f1.2...)


I'll take a 16-50 DA* over a 24-70 F4 Canon L all day long. And as a matter of fact, my video comparing the Canon 6D FF with 24-70L F4 vs the K3II with Tamron 17-50mm F2.8 photographing a 1 shot 4 foot pano print is all about why I choose the APS-c for smaller cheaper, faster and better IQ...


I always hear a lot of talk about this and that but very few examples of photos that demonstrate all these theoretical advantages. And I know why.

---------- Post added 07-06-16 at 03:52 PM ----------

QuoteOriginally posted by Rupert Quote
Ricoh has been good for Pentax and for us. So unlike Hoya that almost ruined Pentax.

True that!


Lets hope they still have the lens engineers to get things going. So far they have trickled out about 1 new lens a year. (Not counting those made by other manufacturers with a Pentax name badge.)
07-07-2016, 07:03 AM   #42
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QuoteOriginally posted by WPRESTO Quote
Originally posted by henryk Quote
250 mm x 1.5 crop factor equals 375mm, not 425mm.
Correct. Realized my error about an hour later while out driving, but forgot to make the correction when I got home four hours later. A little early onset Alzheimer's can relieve you of so many worries. I will go make the correction now, before I forget.
I used to have an anatomical ruler that was off by about 50% to the longer side.....came in handy at times...could be very impressive to those not particularly familiar with measurements.....

Regards!
07-07-2016, 08:22 AM   #43
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QuoteOriginally posted by Qwntm Quote
Sort of, sort of not.


The 24-70 F4 is still F4 and lets F4 amount of light in. The 16-50 is still F2.8 and lets 2.8 amount of light in.
I have no intention of repeating the whole equivalence debate here, but for what it's worth: I'm a believer (mostly, anyway).

QuoteOriginally posted by Qwntm Quote
I'll take a 16-50 DA* over a 24-70 F4 Canon L all day long. And as a matter of fact, my video comparing the Canon 6D FF with 24-70L F4 vs the K3II with Tamron 17-50mm F2.8 photographing a 1 shot 4 foot pano print is all about why I choose the APS-c for smaller cheaper, faster and better IQ...
That video is not up yet? Unless it's
, but I'd think the point of that was testing pixel shift?
07-07-2016, 04:01 PM - 1 Like   #44
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I will certainly keep my K-S1 along my K-1, because it is a lightweight and very capable camera. The K-S1 with the DA 21 make an excellent match!
I am not certain to keep the K-5 II, but currently it is my only camera that can wireless trigger an external flash...
07-11-2016, 04:26 PM   #45
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QuoteOriginally posted by starbase218 Quote
I have no intention of repeating the whole equivalence debate here, but for what it's worth: I'm a believer (mostly, anyway).



That video is not up yet? Unless it's this one, but I'd think the point of that was testing pixel shift?


You can believe what you want. The facts are that 2.8 is 2.8 for light gathering. Doesn't matter if it's a 300mm normal lens for an 8x10 view camera or a 300mm tele for APS-c. Period. The depth of field is where the difference lay.


Depth of field is not as important as light gathering ability. And that's what I believe.


As for the video, APS-c is still smaller and cheaper, Pixel shift is better IQ, but without pixel shift the K3II and lens system is at least equal to the 6D and L lens.


I know for sure the D810 and K1 deliver better IQ at 100% than a K3II or D7200 Nikon. The question is: CAN YOU SEE THIS DIFFERENCE in a 30x40 inch print. (I can't.)
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