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10-23-2010, 01:39 PM   #1
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Request for input: A* lenses- 300mm f2.8 vs 600mm f5.6

I've been shooting the A* 600 f 5.6 for over a year now with good results and I've noticed the physical similarity with the A* 300 f2.8. In fact, the former looks just like the latter with the addition of the 2X Rear Converter L.

If this similarity is real, rather than just apparent, then it would seem to make a lot more sense to have the 300 plus the converter. You'd get the same length/speed when the two components were joined but would also have the option of shooting "just" the 300 when you needed less length and more speed. Also, the smaller trunk case that comes with the 300 is easier to transport and you could carry the adapter crosswise in the case or separately in a gadget bag.

Last month, I saw both kits for sale on Ebay for approximately the same price. If I didn't already own the 600, I'd have jumped all over the 300 kit. More recently, a 300 f2.8, in fairly rough cosmetic condition, sold on Ebay for $870. Unfortunately, I didn't have the nerve to sell my 600 quickly and so didn't have sufficient funds to purchase the 300. Also, the appropriate rear converter seems pretty hard to find.

Does anyone on this forum have real experience with both lenses and the converter? Is there any advice you'd care to give about moving from the 600 to the 300 plus converter? What about stacking a second 2x to the 300 to more-or-less equal the 600 with one converter.

Thanks in advance for your advice.

Sig


Last edited by Sigmoid; 10-23-2010 at 05:25 PM. Reason: typo discovered
10-23-2010, 02:27 PM   #2
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An interesting perspective, Sig. In fact, that's the way I think about my A*400mm (when I'm not dreaming about an DA* 250-600mm F5.6 ED ;~)
10-23-2010, 05:31 PM   #3
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Appreciate your input

Thanks, Dave-

It does sort of throw open the question of "prime-plus-TC" vs "Longer prime" that I've considered over the years. I've never owned a genuine Pentax TC and all of the 3rd party units I've experienced have been pretty trashy, except a Sologor "Flat Field 7 Element" 2X from 30 years ago. I think that one may have graded out as "adequate" by current standards but, alas, I swapped it away long ago.

Sig
10-23-2010, 06:04 PM   #4
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I'm certainly not a lens expert but I do think you're better off using Pentax TCs with Pentax lenses. I sometimes use a Tamron 1.4x when I'm more concerned about light than magnification but otherwise stick to the AF 1.7x, A 2x-s and A2x-L

10-23-2010, 07:35 PM   #5
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I have both the A*300/2.8 and the A*600/5.6. Please note that the A*600mm just came last week, so I have only used it once but I think these 2 pictures are reasonably accurate to show the drop in quality when using a 2X converter. I'll take some pics seeing a shot using the 600mm compared to the 300mm + the 2x teleconverter, but there is some rain heading our way, so it might be a number of days before I can shoot some picks with both.

The first is the A*600 on it's own;


The second is using the 2X-L converter (which from what I understand is the best 2X available). The drop in quality is fairly obvious with the 2X;



I was very careful taking both shots using a tripod, remote with 3 sec timer, etc., but as mentioned, I've only taken a few pictures with it, and the shots were a little front focused.

If I had to choose just one, I would have a very hard time. Unlike the 600/5.6, the 300/2.8 can still be easily used hand held. The 600mm is a very compact lens for it's focal length and my first impressions are very favorable.

Overall, I think you'll be happier with shots at 600mm using the lens you have vs the 300mm + the teleconverter. With that said, I sold my DA*300 after getting the A*300, at least for me, it was that good.

Is there one focal length you would see yourself using more often?

Steve
10-23-2010, 08:00 PM   #6
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Thanks for your input!

Steve,

There definitely are times when I need a 600 and sometimes I'd like even more, especially for nesting birds where the nest isn't approachable on foot or by vehicle.

Right now, I don't have any lens between my 200 DA f2.8 and my 600. I would love to get a fast 300 or 400 for field sports (football, rugby, etc.). Although I'm something of an equipment junkie, I'd still find it hard to justify having both the 300 and 600 unless the 300 plus converter is noticeably inferior to the 600 by itself. As I said in the original posting, a casual inspection suggests that the 600 really is just the 300 plus the 2X permanently joined. I hope that you do get a chance to post some photos comparing the two set-ups.

If the 300 plus converter is noticeably inferior to the 600, then I'd have to consider a 300 DA f4 or maybe a 3rd party lens or (horrors) a zoom.

My question is really whether the gain of the 300 f2.8 for use on a monopod by itself and with the 2X Rear Converter L on the Wimberly would balance out the hassle and expense of selling off the 600.

Any input from other users of these two lenses and the converter in question would be greatly appreciated.

Jim

Last edited by Sigmoid; 10-23-2010 at 08:11 PM. Reason: Typo correction
10-24-2010, 04:50 AM   #7
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Hi
I have been using A*300f2.8 a long time with converters, and I must say I have been disappointed with the 2XL converter; image quality drop is too much for me; on white birds also the combo exhibits a blue halo which needs 3 stops (f8) to disappear; the 1.4 L was better though, image quality drop was less noticeable; I have replaced it with a DA 300 f4 and a 600 (and kept the 1.4 converter) and this is night and day. The A*300 f2.8 is an excellent lens though.
Regards
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