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11-21-2011, 01:12 PM   #1
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Teleconverter for Macro

I own a FA 50mm 2.8 Macro and i think its a really good lens but sometimes i want to take bug pictures and for maximun magnification i need to get too close to the bug so it flies away. So i decided to get a 2x tc but im not sure which one will fit my needs.

I dont care if it cant autofocus but i want it to be cheap and with a good IQ.

any thoughts?

thanks and sorry for my english

11-21-2011, 01:22 PM   #2
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Why not get a longer lens? I think a teleconverter would make the setup a lot less reliable as far as IQ and exposure goes.

Tamron SP 90mm f/2.8 Di Macro Autofocus Lens AF272P700 B&H Photo

Another option is the Pentax 100mm, but having the aperture ring is nice for macro IMO.

Adam
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11-21-2011, 01:31 PM   #3
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Because i cant afford to get a new lens. thank you
11-21-2011, 01:42 PM   #4
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You should read : https://www.pentaxforums.com/forums/pentax-lens-articles/152336-cheap-macro-b...ml#post1583483. There are other means to get cheap macro setups. For example, why don't you consider extension tubes.

Food for thoughts...

11-21-2011, 02:11 PM   #5
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Just so you understand a tele converter will increase the magnification, but it will also cost you 2 stops.

Additionally, there are not many teleconverters that support pentax AF, and correct for aperture reading at the camera, so that your P-TTL flash will work without radical (1-2 stops) of exposure compensation

the best bet is the SMC-F 1.7x AF TC
11-21-2011, 02:23 PM   #6
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I dont use extension tubes because what I am searching for is a longer focusing distance and not more magnification. OR does tc increase both or only magnification?? i think i am confused now; would a 50mm macro with a 2x tc become a 100mm macro?

I understand macro will cost me 2 stops but i dont really care since i use aperture at about 8 to increase dof. AF is not important to me when shooting macro i think that manual focus is easier.
11-21-2011, 02:32 PM   #7
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QuoteOriginally posted by El Pentaxero Quote
I own a FA 50mm 2.8 Macro and i think its a really good lens but sometimes i want to take bug pictures and for maximun magnification i need to get too close to the bug so it flies away. So i decided to get a 2x tc but im not sure which one will fit my needs.

I dont care if it cant autofocus but i want it to be cheap and with a good IQ.

any thoughts?

thanks and sorry for my english
Let me introduce you to the infamous: Vivitar 2x macro focusing teleconverter.
This little gem which can be had for as little as 40USD will turn any lens into a 1:1 macro focusing lens w/A function if applicable. - NB. I inadvertently wrote AF in my initial comment which was incorrect. Some TC's(PK/A) can transmit lens information and controls but not AF(sorry for the confusion).


image courtesy of: pentaxdslrs.blogspot.com

And a few samples:

Taken with SMC-A 50mm 1.7


Taken with SMC-A 50mm 1.7


1:1 CROP

Hope this helps.

PS. I like the Vivitar 2X Macro TC so much that I've purchased three of them over the run of two years. One of which was NIB on eBay for under 100USD

Hope this helps.
JohnB

Last edited by JohnBee; 11-21-2011 at 07:52 PM.
11-21-2011, 02:37 PM   #8
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hey John i like that TC i will check for prices, but i have another question now . Will using that tc with my 50mm MACRO LENS make it a 100mm MACRO LENS or would still be a 50mm Macro Lens with a higher magnification?? I am a bit confused now .

11-21-2011, 02:52 PM   #9
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Hi Pentaxero,

Any 2X TC will make your FA 50mm into a 100mm (macro abilities are retained and probably even takes your lens to better than 1:1).
Same as any 1.4X or 1.5X or 1.7X, or whatever X TC.

Which are the good ones is a different story--I use the SMCP-F 1.7X AFA which is highly regarded and sought after (with good reason) but, alas it is expensive.

Generally people are concerned about image quality degradation when using a TC (any of them, including the good ones), but your FA 50 is so good to start with, you won't see nearly as much degradation as with other lenses.

Also, shooting Macro (close to your subject) you will still allow you to render lovely defocused areas even at smaller apertures such as f/8.

-W
11-21-2011, 03:04 PM   #10
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thanks for the info W.

John, would the vivitar 2x let me use the A setting in the FA 50mm?
11-21-2011, 03:26 PM   #11
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I have no experience with Vivitar but I do own both DFA50 macro and AFA1.7x TC. They pair well, resulting in a lens that behaves like 85mm f4.5 with max 1.7:1 magnification ratio. wide open some contrast is lost, but at f8 no isssue at all.
11-21-2011, 04:39 PM   #12
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You don't need a macro TC as you are looking for magnifying the image at a fixed focus distance; but in fact the vivitar macro is a fine 7 element TC. You can get them with an A setting--I have the non A version.

I think you will find the results of using a TC to be excellent--not withstanding all the discussion about loss of IQ. I would worry less about loss of IQ if it is a reasonably well made one (flare is potentially the bigger problem). Enlarging your image in pp will always IMO lead to a poorer image than a TC.

I suggest you buy a cheap vivitar or comparable one (used about $15.) or the fine Vivitar macro (used $30-50 maybe) whether with an A setting or not. Based on direct experience you can then go further if need be. A 1.7X may be too little. How much magnification do you need--you know how small the bugs are when you get a picture just outside their "fear distance" (as I think Shaw terms it) In fact you may want a 3X TC.
11-21-2011, 06:49 PM   #13
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QuoteOriginally posted by El Pentaxero Quote
thanks for the info W.

John, would the vivitar 2x let me use the A setting in the FA 50mm?
Yes If you get the PK/A version.
Though you will not have AF.

Last edited by JohnBee; 11-21-2011 at 07:46 PM.
11-21-2011, 07:16 PM   #14
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I don't know if the last reply meant to say AF or w/ A setting for the Vivitar 2x TC. The Vivitar macro did not come in AF version as far as I know. But I am almost positive it did come with A setting, but I have no experience with it. Mine is the plain K mount.
11-21-2011, 07:45 PM   #15
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QuoteOriginally posted by dms Quote
I don't know if the last reply meant to say AF or w/ A setting for the Vivitar 2x TC. The Vivitar macro did not come in AF version as far as I know. But I am almost positive it did come with A setting, but I have no experience with it. Mine is the plain K mount.
Good catch!
My last comment is definitely misleading with the term AF(sorry about that). If the TC is the PK/A version(with contacts) the A functions are maintained. However to my knowledge none of them transmit auto focus. This despite the fact that the TC is called Focusing(IOW. can be focused independently).

Hope this helps clarify things.
JohnB
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