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07-18-2012, 11:53 AM   #16
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QuoteOriginally posted by Shanti Quote
Hi Frogfish... so the 300 DA is by far the best..the 55-300 was an option but it seems very poor in comparison... the Sigma 150-500 is about the same price here as the 300DA..so between those 2 I guess, for CaNikon a similar setup with 300mm F4 costs alot more than the Pentax system,and neither are really WR.. can you still get the Pentax TC 1.7? can't find it new anywhere.... I know 2k is not alot for a birding setup,but this project is mostly for fun & learning so have to watch those $$$..boring I know.. they are alot of Buzzards here where I live and really want to get some good shots of them in flight if possible..
The DA*300 is a stellar lens. AF is not the fastest around but it is very fast if only changing focusing over short distances e.g. 20m to 15m but if you miss focus and it has to travel the whole length of it's focus travel then that's about 1 sec in one direction and 2 secs in the other (I have the exact figure somewhere). It is superb on a K5. Add the AFA x1.7 and it's a very good 510mm for a lot lot less than you'll pay for e.g. a Sigma 500mm which is about the cheapest dedicated 500 you can buy for Pentax (others are all out of production and very expensive to buy used). Of course adding the AFA means a weakness in your WR system and you'd need to protect it from the elements in actual use. It is excellent for BIF though for the reasons described below.

The Pentax AFA x1.7 can still be found regularly (Pentax do not make it new for export any more but pre-Earthquake you could buy them off the Japanese Amazon / EBay (I forget which - I did see them on there) for the standard new price of ca. $350 (depending on exchange rates). You can use Google Translate to read the pages .. or there are Japanese forwarding companies that advertise their services, for a ca. $20 fee they will buy products for you and forward them directly onto the address you gave them ... of course importing into your country you then have import duty and VAT/State taxes to pay, so it may still be cheaper to buy used off EBay or from BH, KEH or Adorama if and when they have them in stock (set up alerts).

A little about the AFA (this is not my work but I clipped and kept this information, which is absolutely accurate) :

The AFA is not the usual TC. It was originally designed to allow AF with the most common MF lenses when Pentax trasitioned to AF bodies, so it was essentially set up to adapt the normal 50mm lens to AF. With a 50mm, the user just needed to set the focus on the lens to infinity, and the AFA would allow AF throughout the full focusing distance range of the lens. It acts as a TC because of the additional distance added to the back of the lens. The thickness of the AFA was determined by the amount of movement that was needed to get full range AF with a 50mm lens, and this turned out to be close to 1.7x, so they settled on this to get a relatively easy conversion in aperture value (@ 1.5 stops).

Because it was set up for the 50, when used on a longer lens, the focusing range is more limited, and the user needs to manually prefocus to get the lens within the AFA's range, but you can actuate AF before prefocusing, and the AFA will automatically take over when the lens gets within range, so the operation is easy. This gives the shooter two major advantages.

1. AF is extremely quick, once you get within range. The focus throw of the AFA is very short compared to any lens, and the AF elements are small and light.
2. Since the AFA has a limited focusing range, it acts as a focus limiter, and since the focusing range is relatively short, full range hunts only take a fraction of a second, and reacquiring the focus is easier since the subject usually doesn't go to a total blur. Ever have a lens constantly go past focus both ways -- you can see it approach, miss, and go past the focus point, and it's virtually impossible to stop the AF so it is close enough to be able to zero in on the focus point? The best way to get a focus lock is to manually focus the lens so it's as close as possible, then let AF do the rest. The limited range of the AFA usually doesn't allow this much of a miss unless the light is so low that the AF system is incapable of getting a lock. It's like having Quick Shift focusing with every lens.

07-18-2012, 01:07 PM   #17
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I've owned or rented these lenses over the past 2 years and the New Sigma 50-500 APO DG OS HSM is the best of the bunch.
150-500mm F5-6.3 APO DG HSM

50-500mm F4.5-6.3 APO DG OS HSM***

50-500mm F4-6.3 EX DG HSM
07-18-2012, 02:55 PM   #18
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QuoteOriginally posted by Fl_Gulfer Quote
I've owned or rented these lenses over the past 2 years and the New Sigma 50-500 APO DG OS HSM is the best of the bunch.
150-500mm F5-6.3 APO DG HSM

50-500mm F4.5-6.3 APO DG OS HSM***

50-500mm F4-6.3 EX DG HSM
is it so much better than the 150-500? can you hand hold it(in good light of course)?
07-18-2012, 07:43 PM   #19
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At 500mm they are very close in IQ but I think the 50-500 is just a little better, maybe not 600 dollars worth but If I was going to spend the money it would be the new 50-500.

07-19-2012, 04:07 AM   #20
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The biggest thing with birding is figuring out how to get close to the birds. Even at 500mm on a crop frame, birds are awfully small and you just have to crop down. I just have the DA 55-300 and it works OK, but the biggest problem is that I am shooting at f7.1 most of the time and if light gets poor at all, my iso goes way up and images start to suffer. Not sure about the 560mm prime that is coming from Pentax this fall, but that might be a reasonable option too, depending on price, focus capability and image quality.

07-19-2012, 05:52 AM   #21
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QuoteOriginally posted by Rondec Quote
The biggest thing with birding is figuring out how to get close to the birds. Even at 500mm on a crop frame, birds are awfully small and you just have to crop down. I just have the DA 55-300 and it works OK, but the biggest problem is that I am shooting at f7.1 most of the time and if light gets poor at all, my iso goes way up and images start to suffer. Not sure about the 560mm prime that is coming from Pentax this fall, but that might be a reasonable option too, depending on price, focus capability and image quality.
yes I know getting close is the challenge..but the buzzards here come close to the ground when hunting and that is where I want to capture them...
why 7.1 on that lens..is that the optimum aperture
I imagine the 560 will be good but prob.$$ 2K or more...
07-19-2012, 07:54 PM   #22
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I thought The 560 is a non * or Limited so I doubt it will be over $1500.00...
07-20-2012, 01:16 AM   #23
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QuoteOriginally posted by Fl_Gulfer Quote
I thought The 560 is a non * or Limited so I doubt it will be over $1500.00...
One ITK part-time tester for Pentax (Falk Lumo) wrote a long piece on the 560 (Google it) and estimated the cost at US$2,000 - 2,300 I think he said. The cheapest 500mm around (excluding Mirrors) is the Sigma at US$5,000. I really doubt Pentax are going to put out a 'cheap' crappy 560mm. It may not be weather sealed, highly improbable from it's design, so not earn a * but it should still be of high quality.

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