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05-02-2009, 04:01 PM   #16
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It is the current version, 100-300mm f/4 EX DG IF.

05-02-2009, 04:18 PM   #17
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Thanks bud - i was thinking i might look out for one if it was an old K mount model.

Maybe not now though
05-02-2009, 04:28 PM   #18
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Pentax K 6-2X Rear Converter

QuoteOriginally posted by Squier Quote
Thanks bud - i was thinking i might look out for one if it was an old K mount model.

Maybe not now though
Squier,

Here's an old K model rear converter. I haven’t used my Pentax KT6-2X rear converter with my M 400/5.6 yet so this thread prompted me to give it a try. It might be of interest to those with older K or M series lenses. With the 2X on the back of this lens we are working with a focal length of over 1100mm or so and f 11.2. These numbers are so large they just seem silly. In any case it was fairly windy and a bit overcast so I had to use a relatively slow shutter speed. I've been trying to get close to some Black Birds but 400mm didn't quite get me close enough. The 400 and 2X is another story altogether. This was the best I could manage today.

Red Wing Black bird




Last edited by 8540tomg; 05-02-2009 at 04:38 PM. Reason: typo
05-02-2009, 04:34 PM   #19
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Thats good detail IMO, for a black coloured bird at distance, and with a light background.

I find trying to shoot a Tele with such differing contrasts between subject and background makes one underexpose and the other overexpose.

I have a Panagor 2x TC that i havent experimented with yet - i'm waiting for a K mount @ 300mm + before i give it a work out

05-02-2009, 04:44 PM   #20
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QuoteOriginally posted by Squier Quote
Thats good detail IMO, for a black coloured bird at distance, and with a light background.

I find trying to shoot a Tele with such differing contrasts between subject and background makes one underexpose and the other overexpose.

I have a Panagor 2x TC that i havent experimented with yet - i'm waiting for a K mount @ 300mm + before i give it a work out

Thanks Squier,

I was quite pleased with the results this combination managed today. I suspect on a brighter day, with a faster shutter speed and f16 or so, the results might be even better.

Tom G
05-02-2009, 04:50 PM   #21
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I wouldnt mind one of the Pentax A rear TC's to try - maybe the 2X-s or 2X-L ...but they're real pricey.

There's one for sale here at a shop and they want £150 GBP
05-02-2009, 10:20 PM   #22
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For manual focus lenses the best I have is the SMC-F 1.7x AF TC, it adds autofocus to fast MF lenses. I use it with my SMC 300mm F4.

For true auto focus lenses, I only use a TC on my Sigma APO 70-200 F2.8 EX. I have both 1.4 and 2x sigma TCs. they are excellent, but project into the rear of the lens so they are limited to a small selection of lenses.

05-03-2009, 11:01 AM   #23
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QuoteOriginally posted by Squier Quote
I wouldnt mind one of the Pentax A rear TC's to try - maybe the 2X-s or 2X-L ...but they're real pricey.

There's one for sale here at a shop and they want £150 GBP
Make sure before buying an -L converter that the lens is compatible. I lost a shipping fee on a 1.4X-L because the throat of my M 400 is too small, and the L series project into the lens. The 1.4X-S does not project and can be mounted on any lens. I am sure the -L would give me better images than the -S, but it won't take any images when you cannot mount the lens.

I am in the throes of testing the AF 1.7X on all my lenses, and so far I am pleased. The images with the 400 seem just a little bit cleaner with the 1.7X than the 1.4X. I sure don't care for working with a lens with a maximum aperture of f/9.5, though.

I guess I'll have to get a DA* 300/4 to replace my 400. 510/6.8 is a bit better for aperture, but a lot shorter than even 560mm f/8, let alone 680mm f/9.5. LBA strikes again.
05-03-2009, 11:23 AM   #24
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Yes, i've got the list of Pentax lenses that those X-L TC's will fit because of the protrusion. I'm more likely to buy an X-S i reckon.

What is the AF 1.7x you mention ? Is that a Pentax TC or 3rd party TC and does any AF TC affect manual lenses ?
05-03-2009, 11:27 AM   #25
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QuoteOriginally posted by Squier Quote
Yes, i've got the list of Pentax lenses that those X-L TC's will fit because of the protrusion. I'm more likely to buy an X-S i reckon.

What is the AF 1.7x you mention ? Is that a Pentax TC or 3rd party TC and does any AF TC affect manual lenses ?
There are several threads running with reference to the Pentax AF 1.7X converter. It will autofocus [!!!] a manual focus lens within limits. Basically, focus near and let the converter fine tune the focus. I use my copy in manual focus mode, because the AF system is not really happy with a 400mm f/5.6 lens - focusing at 680mm f/9.5 is rather iffy. It's one of the best optically.
05-03-2009, 11:29 AM   #26
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Thanks CR - i'll keep an eye out for one, but as with the X-S TC's no doubt they're
expensive, at least over here they will be
05-03-2009, 11:30 AM   #27
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QuoteOriginally posted by Squier Quote
Thanks CR - i'll keep an eye out for one, but as with the X-S TC's no doubt they're
expensive, at least over here they will be
They are expensive here as well. I paid US$400 for my copy. I've not seen one go for less than US$300 yet. They are not all that common. They show up in the forum marketplace from time to time - that's where I got mine.
05-03-2009, 12:12 PM   #28
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Pentax 1.7 AF Converter

I posted this link in another thread, but I'll repeat it here too. It seems that jinfinance, seller of eBay split-prism focus screens, sells these converters brand new on eBay. While I've read elsewhere that these are out of production, it appears that this seller has access to a cache of NOS converters.
05-03-2009, 10:43 PM   #29
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QuoteQuote:
GMoney: I posted this link in another thread, but I'll repeat it here too. It seems that jinfinance, seller of eBay split-prism focus screens, sells these converters brand new on eBay. While I've read elsewhere that these are out of production, it appears that this seller has access to a cache of NOS converters.
Yes, search his store--I often find useful items there. Just got a good price on a Marumi Graduated ND filter for my Tammy from him.
05-03-2009, 10:58 PM   #30
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PMFJI

Has anyone compared the shots with and without TCON, in any combination, by taking the same shot with and without, then zooming the Tcon shot to, say 100% and the non-Tcon to 140%, and seeing whether there is actually a gain? I am not in the big league (yet), but I bought a 1.4X Raynox TCon for my bridge camera, and that was the only real test that counted AFAICS. I found that in my case, it was not worth using the TCon. There was no gain over simply cropping.

While that was all done at the lower end of the pool, I feel it still applies.
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