Pentax F 1.7x AF teleconverter -LIVES AGAIN!


pinholecam

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Jul 23, 2007
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Certainly some good news running up to 2010. :)

The Pentax F 1.7x AF teleconverter seems to be now manufactured new in Vietnam.
I was able to obtain this from a shop in Japan. New with warranty.


The Box (says made in Vietnam)
K7JP0570.JPG


Hoya declaration and warranty (ie. a recent event; so this is not old stock)
K7JP0571.JPG


The teleconverter
K7JP0572.JPG


For those who what to know what the big fuss this is about, this teleconverter is truly unique. Firstly, Pentax does not have a teleconverter in the DA series (ie. now). Secondly, its a very good teleconverter with a 1.7x magnification. Now, the most important part is that it has a focusing element within the teleconverter (no one else has this). With this, a Manual lens becomes an auto focus lens (yes, I did not type it wrongly).


So start pulling your Jap connections and get one :D
 

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pinholecam... you very poisonous leh.

Just when i thought it's safe to surf the forum and i get this... 1.7x AF teleconverter with magic to convert manual focus lenses to AF.

Congratulations on your new purchase. 'Ow much is it? :sweat:

With 1.7x + 1.5 crop factor... Does this mean a 50mm will become 127mm AND 300mm becomes 765mm? That's crazy magnification :bigeyes:
 

pinholecam... you very poisonous leh.

Just when i thought it's safe to surf the forum and i get this... 1.7x AF teleconverter with magic to convert manual focus lenses to AF.

Congratulations on your new purchase. 'Ow much is it? :sweat:

With 1.7x + 1.5 crop factor... Does this mean a 50mm will become 127mm AND 300mm becomes 765mm? That's crazy magnification :bigeyes:

Yes, its magical (and only Pentax has it ;) )
Got it for about $350. Its a steal considering what it does and it used to (actually can still) go for US$450 in forums and ebay.

On some fast lenses it has potential. Too bad I don't have those.
The cost for the focal length increase is of course f-stop (x1.7 as well).
Coupled with a good fast lens, I can imagine.... :think:
A*135/1.8 becomes ~230mm f3.1 almost a modern 200mm f2.8 lens. ( though this lens is expensive as heck and even harder to find)
I see no reason to use a 50mm on it though.

Forget about the crop factor 1.5x. Its equivalent field of view, not magnification.
Just look through a film camera and a DSLR with the same lens and you will see that the magnification is the same, just different crop.
 

With this, a Manual lens becomes an auto focus lens (yes, I did not type it wrongly).

you mean.. even M series will become AF lens? :eek:


i have never used tc before, the focus when using tc is determined by the tc?
 

It is great news for us. I want one also but even second hand price is :bigeyes:.
If it -LIVES AGAIN as you said, then we can expect brand new with standard pricing:heart:.
 

I saw your post on PentaxForums. Any pics to show how it affects the image quality?
 

Was it ever discontinued?
 

Manufactured or Made in Vietnam is totally different from Assembled in Vietnam.
The box shows Assembled in Vietnam.
In this case, components like elements are made elsewhere and shipped to Vietnam for final assembling due to lower labour cost.
 

Thanks pinholecam for the info :thumbsup:
I've been eyeing this item ever since I own a pentax DSLR.

I've just bought it from amazon japan, for <S$300, vpost shipping should be <$30.
I am not sure if can get cheaper, but I am not going to wait to find out.

http://www.amazon.co.jp/gp/product/B002HJUMF0/ref=s9_simi_gw_s0_p23_t1?pf_rd_m=AN1VRQENFRJN5&pf_rd_s=center-1&pf_rd_r=1BPBAMQYNDMGGKRVX426&pf_rd_t=101&pf_rd_p=463376736&pf_rd_i=489986
 

the focusing is awesome, but won't 1.7x alter your lens rather significantly?
 

you mean.. even M series will become AF lens? :eek:


i have never used tc before, the focus when using tc is determined by the tc?

This TC have moving elements. It is not totally AF. It is more of assist the manual lens to AF. Unless you shoot infinity with the lens all the time, for nearer distance, you will have to pre-focus the lens to the nearest point and the TC will do the fine adjustment.

It works very well with f/4 and faster lenses. When use it with a 50 f/1.4, it becomes a 85 f/2.8 and focus fast too.
 

This TC have moving elements. It is not totally AF. It is more of assist the manual lens to AF. Unless you shoot infinity with the lens all the time, for nearer distance, you will have to pre-focus the lens to the nearest point and the TC will do the fine adjustment.

It works very well with f/4 and faster lenses. When use it with a 50 f/1.4, it becomes a 85 f/2.8 and focus fast too.
Yes, noticed that as well. Since the lens element only needs to travel a short distance unlike the whole focus throw on a normal lens, focusing becomes very fast.


Thanks pinholecam for the info :thumbsup:
I've been eyeing this item ever since I own a pentax DSLR.

I've just bought it from amazon japan, for <S$300, vpost shipping should be <$30.
I am not sure if can get cheaper, but I am not going to wait to find out.

http://www.amazon.co.jp/gp/product/B002HJUMF0/ref=s9_simi_gw_s0_p23_t1?pf_rd_m=AN1VRQENFRJN5&pf_rd_s=center-1&pf_rd_r=1BPBAMQYNDMGGKRVX426&pf_rd_t=101&pf_rd_p=463376736&pf_rd_i=489986
Thanks for the tip. Mine was from a brick and mortar shop so maybe a bit more expensive. If everyone can order from your link that will be nice.


wa.. is there a 1x af teleconverter? :bsmilie:
Ha.. ha.. my thoughts exactly.
 

Yes, noticed that as well. Since the lens element only needs to travel a short distance unlike the whole focus throw on a normal lens, focusing becomes very fast.

My drawback with this TC is that it is fixed to center focus point when using with AF lenses also. Find it inconvenience sometimes when use it with tele lens on tripod.
 

a 500mm f6.7 will become 850 at f8 or 7.x? my concern is that is 850 f8/7.x usable...:dunno: (before factoring 1.5x)
 

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Here are some test shots.
I might be doing something incorrectly, so the experts can let me know what (ie. wrong crop size, wrong to compare diff magnification, etc)
Taken using a SMC-K 135/2.5 at f2.5 (Portrait setting; ie. all settings at neutral)

Without teleconverter
K7JP0654.JPG



With teleconverter
K7JP0655.JPG



Without teleconverter 100% crop
K7JP0654.JPG

With teleconverter
K7JP0655.JPG
 

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a 500mm f6.7 will become 850 at f8 or 7.x? my concern is that is 850 f8/7.x usable...:dunno: (before factoring 1.5x)

Thats why its limited to fast lenses mainly. For slow lenses, the slow shutter speeds required due to the reduced effective aperture will make AF hard/impossible and darken the viewfinder as well.

I did try it on my 400/4.5 and it was ok.
500/6.7? Bigma? I've never seen a report that mentioned favorable results for this lens + teleconverter. (Maybe did not look hard enough)
 

a 500mm f6.7 will become 850 at f8 or 7.x? my concern is that is 850 f8/7.x usable...:dunno: (before factoring 1.5x)

A 500mm f/6.7, it will be 850mm f/11. Too dark, the AF is not going to work so reliably and you will need very good lights or you will find yourself needing to use higher ISO setting.