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02-04-2010, 09:47 AM   #16
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Pentax 2x converter with the DA*300

QuoteOriginally posted by jpzk Quote
Thanks Wally.
I guess I am too eager to have access to a "longer" lens, but my actual combo : DA*300/4 plus the Tamron 1.4x should suffice for the moment.
I have received some days ago the Pentax Rear converter A 2x-S. I find the results with my DA*300/4 of excellent quality, very sharp, no increase of CA, clearly better then the Kenko 1,5x SHQ (it's a bit soft). With an effective f8 autofocus wouldn't work very well, anyway, and with this adapter it functions like an A-Lens, Focus trapping works, and you can introduce the right focal lenght for SR. I got it quite cheap for 99$ on ebay. Precise focussing is not easy, but trying several fine adjustments it is possible to get it right.

Here you can see the moon with this combo, taken this morning at 6:18 (100% crop, K10D, 1/100 s F5.6, ISO 100, Tripod, cable release, 2s timer for mirror lockup)




Regards
Klaus


Last edited by Klaus; 02-04-2010 at 10:19 AM.
02-04-2010, 12:55 PM   #17
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Two cents or less...

Just a bit of personal experience.

When birding with a DA300/f4 and a Tm 1.4x TC, I found the image quality to not be siginificantly degraded, but the autofocus time was. Thus, from now on birds in flight or fast motion shots must be performed w/o the TC. The TC will only be used for static shots such as birds in nest or on a branch).....
02-04-2010, 01:38 PM   #18
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QuoteOriginally posted by Lowell Goudge Quote
I use the SMC 300F4 and 1.7x quite a bit and in 2 different ways.

I use it with flash (along with better beamer extender) on my *istD since the *istD has TTL capability, and I use it at high ISO on my K7 thanks to the High ISO perfromance and shake reduction.

It fell out of use a little on the K10D due to limited ISO and no TTL flash.

I can see where it would be very nice on the DA 300F4 since it corrects for aperture reading, and offers range limited AF. withMF override on the lens itself.

Since many nature shots are through branches etc, a degree of MF is nice to insure you focus on the subject and not the surroundings
This might convince me to get one of those better beamers. Now that I have the flash, this might be a good idea. However, I have never used a flash for willdlife shoots and I am still trying to get acquainted with the AF540FGZ. The K7 should be able to handle flash in that manner you describe.
As for the AF 1.7x adapter (TC) ... well, I am still looking for one at a reasonable price. Those on sale at eBay are way overpriced. I am not so sure that Pentax will one day re-release it.
That is true regarding focusing on the subject and not letting the camera focus on branches. I had my fair share of this and I have switched to manual, unless there is absolutely nothing in the way.

JP
02-04-2010, 01:41 PM   #19
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QuoteOriginally posted by Klaus Quote
I have received some days ago the Pentax Rear converter A 2x-S. I find the results with my DA*300/4 of excellent quality, very sharp, no increase of CA, clearly better then the Kenko 1,5x SHQ (it's a bit soft). With an effective f8 autofocus wouldn't work very well, anyway, and with this adapter it functions like an A-Lens, Focus trapping works, and you can introduce the right focal lenght for SR. I got it quite cheap for 99$ on ebay. Precise focussing is not easy, but trying several fine adjustments it is possible to get it right.

Here you can see the moon with this combo, taken this morning at 6:18 (100% crop, K10D, 1/100 s F5.6, ISO 100, Tripod, cable release, 2s timer for mirror lockup)

Regards
Klaus
A rear converter is something I have not thought about but it looks like it did the job for you. Good moon pic.
Thanks for the info.

JP

02-04-2010, 01:45 PM   #20
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QuoteOriginally posted by cdurfor Quote
Just a bit of personal experience.

When birding with a DA300/f4 and a Tm 1.4x TC, I found the image quality to not be siginificantly degraded, but the autofocus time was. Thus, from now on birds in flight or fast motion shots must be performed w/o the TC. The TC will only be used for static shots such as birds in nest or on a branch).....
I think you point out a very real fact about using the Tammy TC and the DA*300. I tried it today, on gulls, and the AF was, as you said, hunting a bit. But not that much, really. Maybe it's the K7 performing better? But for static, or almost static, subjects, it is quite precise I must admit.
Given that it gives a 420mm range ... not bad.
B.I.F.: I would be hesitant to test the DA*300 and TC on a flying falcon. But I will try it out on more familiar and less speedy birds first.

JP
02-04-2010, 03:50 PM   #21
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QuoteOriginally posted by Klaus Quote
I have received some days ago the Pentax Rear converter A 2x-S. I find the results with my DA*300/4 of excellent quality, very sharp, no increase of CA...
Interesting. I was a bit disappointed by my results with that combination but this encourages me to give it another try.
02-04-2010, 05:23 PM   #22
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QuoteOriginally posted by Ben_Edict Quote
Never heard of Novoflex, oops… Here is the company: Novoflex - Home
Very interesting site and well laid out.
They don't actually manufacture the rapid focus lenses anymore, but they still sell the adapters to fit most cameras on the market, including K-mount.
Yes, I have checked that on the Novoflex website and they do have the adapters.
But you will find them on ebay easily. In the pre-AF aera. the Novoflex lenses were pretty much the standard for wildlife photography, but there quality did not diminish mysteriously with the advent of AF… They are very useable without a tripod, thanks to the grip stock and the shoulder rest, which gives them the appearance of a bazooka: Foto Novoflex T-Noflexar 400/5,6 - Bild von Carsten Lynker aus - Fotografie (9145615) - fotocommunity.de
I almost choked when I first saw the size and "allure" of this thing. Indeed it looks like a machine-gun.
If you are lucky you may also find a Leica Telyt lens for the Novoflex (the lens heads are interchangeable), which is still a very high quality lens.
I am surprised to see that you can actually change lens type with this set up.
Otherwise the 3-element T-Noflexar 400/5.6 would be the lens of choice and I very much prefer the latest model, as the massive aluminium tubing is more robust than the bellows focusing unit in the earlier lenses.
I have made an inquiry to a seller who has one for sale but there is no explanation whatsoever about if there is an adapter on it already, nor the spec's of the "lens". I am waiting for a return email.
The images are sharp in the center (very sharp), but there is some fall-off towards the ccorners. This is less pronounced with APS-C cameras and all in all usually not a problem for nature photography - you don't make repros with a 400mm lens… Colour fringing in high contrast conditions is there, but very low and easily correctable in pp.
The corners wouldn't really matter; you can always frame a bit wider then just crop them out.
For the Sigma 70-200 - you should really use these lenses with the original Sigma Apo tcs. With the 1.4x modell, the IQ is quite as good as the naked lens provides and the image degradation with the 2x tc is hardly noticeable. One of the best zoom+tc-combos "out there".
I made a mistake here: the 70-200/2.8 I own is a Tamron, and I have the Tamron 1.4x TC. Guess what: I never tried it out! If it works good, I might consider getting a second Tamron TC and stack them. Might even try that combo on the DA*300.
Of course, it would be nice to have one of those AF1.7X Pentax "adapter".

Ben

Thanks again for all of the very timely information.
JP

EDIT: some image-examples:

Manual Focus Lenses :: View topic - Novoflex T-Noflexar 5,6/400 (2)
Lachmöwenportrait und erstes Testfoto mit Novoflex (Forum für Naturfotografen)
Foto Kleiner Fuchs - Bild von Carsten Lynker aus Edelfalter - Fotografie (9296246) - fotocommunity.de
Foto Insektenmakros mit dem Novoflex Schnellschussobjektiv - Bild von Carsten Lynker aus - Fotografie (9296265) - fotocommunity.de
Ben, I just checked those images and some of them are really excellent.

P.S.: Just received an answer from seller; all she knows is that it is a Noflexar 1:56 f40cm P42884.
It was part of her late's husband's photo gear.

Last edited by jpzk; 02-04-2010 at 05:51 PM. Reason: added info
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