Veteran Member Join Date: Oct 2006 Location: Chicago suburb, IL, USA |
Hi Kameko,
I'm primarily a birder, and though I could easily afford to switch systems, I've never been seriously tempted. The main reason is the very unique-to-Pentax F 1.7x AFA (yes, I am aware of the Nikon version which is not nearly as easy to use nor as universally compatible). Most of my ultra tele lens choices have revolved around using them with the AFA, so f4-f4.5 is about as slow as one can go in max aperture to get useful AF -- as you've noticed f8 is about where Pentax AF starts to really struggle in other than optimal light.
For every day walk around shooting (I don't use hides or camo) I use my K-3 with my well used FA* 300/4.5 + the AFA for 510mm f7.7. This might sound pretty slow, but it works fine in most daylight conditions, and it's a very compact and lightweight AF 510mm for handheld shooting. It's very sharp with good contrast wide open, so I shoot it that way much of the time, and only stop down a stop or two if I have enough light to keep shutter speeds up.
If I want faster, I'll go with one of my 300mm f2.8s (I started with the Tamron 60B Adaptall 2, moved up to a used Sigma EX 300 f2.8 APO, then found a used FA* 300 f2.8 at a very reasonable price, and kept them all since they can each serve well for different situations. With any of these, I can use the AFA to get 510mm f4.8 in a smaller package that focus much closer than the Sigma EX 500 f4.5. I can also stack either my Tamron F 1.4x AF PZ MC4 or Sigma EX 1.6x APO TC on the AFA to get 714mm f6.7. With the Sigma and FA*, since they are screw drive AF, I can also just use one of the 1.4x AF TCs to get 420 mm f4 if I want that FL, or shoot them bare for 300mm f2.8 if I need the speed and can sacrifice the reach.
If I need more reach, I also carry a Q body and a Pentax K2Q adapter which doesn't take up much space in the bag, but gives me a virtual 3.6x TC that I can use with a DA 55-300 for a 1080mm FOV EQ for handheld, or with the premium glass on a tripod to get a bit better IQ. The IQ doesn't compare to APSC, and of course, I lose AF and a real time VF, but it gets me reach that I can't get with the DSLR, and the IQ is easily good enough for ID shots, and I don't need over $1K in support gear to shoot it, a good CF travel tripod with a gimbal adapter (Wimberley Sidekick or Jpbu Micro Gimbal on a good ballhead) works well for me, and either of these can also give sufficient support on a sturdier tripod and head for 300mm f2.8 class lenses (with TCs, of course) and a DSLR.
The AFA isn't for everyone, as some don't like the need to manually prefocus somewhat, and this makes BIF shooting much more difficult, but I'm not in an area where there are enough species of interesting BIF candidate species, so this is not much of a concern for me. On the plus side, the AFA gives you very fast critical AF, and an automatic focus limiter, which is really useful for those small guys that always seem to perch in the middle of a lot of AF confusing branches and leaves. It allows me to experiment with a variety of MF lenses -- two of my favorites are the 80-200 f2.8 Adaptall 2 and a K mount converted Canon FD 300 f4 L, each of which cost me a bit over $200. IQ is not compromised significantly with premium quality glass, even with a TC stacked on top of it with the fast glass.
I also use the AFA for added magnification and so I can use AF with my 1:1 dedicated macro lenses (D FA 100/2.8 and Sigma EX 180 APO DG Macro. These give me close to 2:1, and the focus range at macro distances is only a few mm, so AF can actually be useful, especially for my favorite macro subjects, jumping spiders, who always seem to be on the move.
There is something to say for easy availability of long fast glass, but Pentax allows me to go long without the bulk and weight of carrying multiple ultra/super teles. From experience, I don't want to lug much more than one 6 lb lens for any distance. I also typically shoot at relatively short distances, almost always under 20 feet, and very frequently under 10 feet, and most, if not all of the lenses over 300mm can't focus that close, so I'd lose a lot of opportunities for the best shots because the birds happen to land too close. This doesn't really happen with a 300mm with TCs as the average MFD is around 6 feet, and it's very rare that I can occupy space within 6 feet of any wild bird. The Sigma EX 500/4.5 is light enough ar @ 7 lbs, but its 13 ft MFD is a deal breaker for me, and changing brands wouldn't be any advantage here because this lens is available in K mt. I've never considered the excellent FA* 600/4 or the FA* 250-600 f5/6 because of their long MFDs and 13 lb weight. All lenses in this class are out of the question for usability for me. Also consider that with the super teles, with all of their weight, need very stable support. If you're shooting a $4K+ lens, it doesn't make a lot of sense to go economy class with the support, and a very high quality set of CF legs with a premium gimbal is called for -- expect to add at least another $1K to the already expensive glass to get the most out of it.
I'll never be a NG photographer or even a pro bird shooter, though it's very satisfying to get a shot with fine feather detail, showing people views of birds that they've never seen. Pentax works well enough for me. Yes, it's difficult to get the fast long glass that's been discontinued, but if you're persistent, it's possible, and worth it. YMMV, of course.
Here are some examples:
The White Throated Sparrow was shot with a K20D, FA* 300/2.8, 1.7x AFA with a Sigma EX 1.4x APO TC stacked, from a tripod w/gimbal. This is from @ 8 ft, and cropped vertically from a landscape shot, sharpened with Topaz InFocus.
The Black Crowned Night Heron is with a K-5, FA* 300/4.5 + 1.7x AFA. This is from about 25 feet, handheld, slightly cropped to 8x10 for composition and printing, sharpened with Topaz InFocus, and with slight NR with Topaz Denoise.
The Ruby Throated HB was with a K-5, Canon FD 300/4 L + 1.7x AFA. This is from 10 ft, off a tripod/gimbal, cropped for composition to eliminate some background, NR and sharpened with Topaz Denoise and InFocus.
The Screech Owl is with the Q, Pentax K2Q adapter, FA 50/1.4 from @ 4 feet, handheld. NR and sharpened with Denoise and InFocus.
Scott
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