K-5 and Extension Tubes

canoetripper · 10-24-2011, 08:16 PM

Please tell me there's a way??

Maybe I did not do enough homework before switching to Pentax. I just assumed that all major brands (I include Pentax in this category) have extension tubes available...that will at least transmit a basic level of data to the lens. I don't care about AF, but exposure would be nice.

Do I have any options? My goal is extreme macro. I have a K-5, a DA 18-55mm (kit lens), and a Sigma 70-200mm f/2.8 APO EX DG MACRO lens. Of course, neither lens has an aperture ring, and so aperture must be controlled electronically, right?

Otherwise, I absolutely love my K-5. But this could be a show-stopper for me.

Thanks!

Kris Cox
Kristoffer Cox Photography

Adam · 10-24-2011, 08:26 PM

The Pentax tubes don't transmit aperture information, but there is a number of third-party ones that do:

Jessops Auto Extension Tubes PK-A reviews - Pentax Camera Accessories: Database and Reviews
https://www.pentaxforums.com/forums/sold-items/99232-sale-sold-kenko-uniplus-...worldwide.html

If you want to use the Pentax tubes, you will need a lens with an aperture ring. I would get an actual macro lens if you plan on doing extreme macro.

Here are a few options, all of which have the aperture ring:
Sigma 50mm f/2.8 EX DG Macro Autofocus Lens for Pentax 346109
Pentax-D FA 50mm F2.8 Macro Reviews - D FA Prime Lenses - Pentax Lens Reviews & Lens Database
Pentax-M 50mm F4 Macro Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database
Pentax-A 50mm F2.8 Macro Reviews - A Prime Lenses - Pentax Lens Reviews & Lens Database

canoetripper · 10-24-2011, 08:45 PM

Adam - Great info. Thanks much!!!

Philoslothical · 10-24-2011, 09:11 PM

Vivitar made a series of extension tubes that can still be found in some shops, or on Ebay, and sometimes the marketplace forum here. The AT-22 model has the mechanical linkage for stopping down when shooting, and the more expensive AT-23 tubes support autofocus with an AF lens.

**Hornet** · 10-24-2011, 10:13 PM

Hi

Another option is to locate some used auto teleconverters (Pentax A are common) and remove the glass elements. Check out the Pentax K mount on Wikipedia first so you know what to look for to get a TC that will work with lenses lacking an aperture ring. When you do this make sure you paint any shiny surfaces on the inside black or you may get some hazy artifacts.

You could also look for used Kenko auto tubes but these are rare and expensive (about $250). I would recommend buying a good macro lens like the Tamron 90mm, sigma 105mm or Pentax 100mm though if you're going to invest this amount on extension tubes.

Hope this helps

RioRico · 10-25-2011, 01:09 AM

Deglassed A-type TCs are the most cost-effective answer I know of. My 2x's averaged US$15 each. They're each 25mm thick, so used together with my FA50/1.4 I get 1:1 magnification. Exact magnification for whatever lens is used depends on the thickness of the modded TCs. Since they're A-type, you can use DA-type lenses without aperture rings.

Pro: Cheap; retain aperture control
Con: None thinner than 25mm probably

You'll likely be shooting your extreme macros in a controlled (studio) setting, right? Then you won't need long lenses, which are preferred in the field. You'll get more magnification by using shorter lenses. Using two deglassed TCs on your kit lens at 25mm (tape it to that focal length!) will give 2:1 magnification. I'll recommend three TCs and a cheap F35-70 zoom. Its optics are a bit better than the DA18-55 and you'll get a little more working room. And it has an aperture ring.

Trying for extreme macro with your 70-200 will require a LOT of extension; it gets unwieldy. If you intend to use that long zoom, consider getting a Raynox DCR-250, which is a corrected +8 dioptre closeup adapter with a working distance of about 5in / 127mm. Magnification = F*D/1000 where F= lens focal length and D= adapter dioptre. So at 200mm, M= (200*8)/1000= 1.6:1. The Raynox doesn't eat light as does extension (tubes-TCs-bellows). And you retain both aperture control and autofocus, for what that's worth (which ain't much!)

Philoslothical · 10-25-2011, 01:37 AM

I have a strong preference for primes when using tubes. They're much more predictable and tend to give better IQ. I've experimented with extension on all my lenses, and found some zooms simply don't cooperate, the focal distance is so close to the front element that you bump your subject (not good if it's alive!). Using diopter lenses on the end of a zoom can be effective though, with the usual caveats about loss of sharpness on edges.

RioRico · 10-25-2011, 02:55 AM

Originally posted by Philoslothical

I have a strong preference for primes when using tubes. They're much more predictable and tend to give better IQ. I've experimented with extension on all my lenses, and found some zooms simply don't cooperate, the focal distance is so close to the front element that you bump your subject (not good if it's alive!). Using diopter lenses on the end of a zoom can be effective though, with the usual caveats about loss of sharpness on edges.

Indeed. The Raynox or even cheap uncorrected +dioptre meniscus closeup adapters can be good-to-great when image edges aren't critical. And primes are better than zooms on extension. OP asked about options for his current (zoom) lenses, and extreme macro, and I commented accordingly. For other options I'll of course point to https://www.pentaxforums.com/forums/pentax-lens-articles/152336-cheap-macro-b...lose-work.html

How to get to extreme (and sharp) macro without spending a lot:

* A good flatfield lens (Industar-50/3.5 or some short enlarger lens) and lots of extension (tubes and/or bellows)
* Reverse-stacking disparate MF primes -- flip a 25mm lens onto a 200mm lens for 8x magnification!

Other than microscopy, those are the most extreme options.

Mike Cash · 10-25-2011, 03:33 AM

I use genuine Asahi Optical extension tubes made in about 1962 for the old S2 film body (pre-Spotmatic). They work just fine.

canoetripper · 10-25-2011, 06:43 PM

Wow--thanks for the great info, everyone! I'm feeling better about the K-5 for macro, and I'm looking forward to trying some of your solutions!

**rod_grant** · 10-26-2011, 03:23 AM

I remember seeing auto tubes for Pentax on a Polish site (@ around $70-75 AUST from memory) but I can't find them now.
Perhaps someone else can help?
- The universal camera; designed in Japan (we assume), assembled in Philipines, lens assembled in Vietnam, extension tubes made in Poland!

**fs999** · 10-26-2011, 08:27 AM

The best close-up is Hoya Pro1D Close Up N°3.
I use it with my 200mm and 50-135mm. Excellent but not cheap...

10-24-2011, 08:16 PM	#1
canoetripper New Member Join Date: Oct 2011 Photos: Gallery Posts: 18	K-5 and Extension Tubes Please tell me there's a way?? Maybe I did not do enough homework before switching to Pentax. I just assumed that all major brands (I include Pentax in this category) have extension tubes available...that will at least transmit a basic level of data to the lens. I don't care about AF, but exposure would be nice. Do I have any options? My goal is extreme macro. I have a K-5, a DA 18-55mm (kit lens), and a Sigma 70-200mm f/2.8 APO EX DG MACRO lens. Of course, neither lens has an aperture ring, and so aperture must be controlled electronically, right? Otherwise, I absolutely love my K-5. But this could be a show-stopper for me. Thanks! Kris Cox Kristoffer Cox Photography

10-24-2011, 08:26 PM	#2
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,594	The Pentax tubes don't transmit aperture information, but there is a number of third-party ones that do: Jessops Auto Extension Tubes PK-A reviews - Pentax Camera Accessories: Database and Reviews https://www.pentaxforums.com/forums/sold-items/99232-sale-sold-kenko-uniplus-...worldwide.html If you want to use the Pentax tubes, you will need a lens with an aperture ring. I would get an actual macro lens if you plan on doing extreme macro. Here are a few options, all of which have the aperture ring: Sigma 50mm f/2.8 EX DG Macro Autofocus Lens for Pentax 346109 Pentax-D FA 50mm F2.8 Macro Reviews - D FA Prime Lenses - Pentax Lens Reviews & Lens Database Pentax-M 50mm F4 Macro Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database Pentax-A 50mm F2.8 Macro Reviews - A Prime Lenses - Pentax Lens Reviews & Lens Database Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

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10-24-2011, 08:45 PM	#3
canoetripper New Member Join Date: Oct 2011 Photos: Gallery Posts: 18 Original Poster	Adam - Great info. Thanks much!!!

10-24-2011, 09:11 PM	#4
Philoslothical Veteran Member Join Date: May 2011 Posts: 1,889	Vivitar made a series of extension tubes that can still be found in some shops, or on Ebay, and sometimes the marketplace forum here. The AT-22 model has the mechanical linkage for stopping down when shooting, and the more expensive AT-23 tubes support autofocus with an AF lens.

10-24-2011, 10:13 PM	#5
Hornet Site Supporter Join Date: Sep 2007 Location: Victoria, BC, Canada Photos: Gallery Posts: 169	Hi Another option is to locate some used auto teleconverters (Pentax A are common) and remove the glass elements. Check out the Pentax K mount on Wikipedia first so you know what to look for to get a TC that will work with lenses lacking an aperture ring. When you do this make sure you paint any shiny surfaces on the inside black or you may get some hazy artifacts. You could also look for used Kenko auto tubes but these are rare and expensive (about $250). I would recommend buying a good macro lens like the Tamron 90mm, sigma 105mm or Pentax 100mm though if you're going to invest this amount on extension tubes. Hope this helps

10-25-2011, 01:09 AM	#6
RioRico Veteran Member Join Date: Jun 2008 Location: Limbo, California Posts: 11,263	Deglassed A-type TCs are the most cost-effective answer I know of. My 2x's averaged US$15 each. They're each 25mm thick, so used together with my FA50/1.4 I get 1:1 magnification. Exact magnification for whatever lens is used depends on the thickness of the modded TCs. Since they're A-type, you can use DA-type lenses without aperture rings. Pro: Cheap; retain aperture control Con: None thinner than 25mm probably You'll likely be shooting your extreme macros in a controlled (studio) setting, right? Then you won't need long lenses, which are preferred in the field. You'll get more magnification by using shorter lenses. Using two deglassed TCs on your kit lens at 25mm (tape it to that focal length!) will give 2:1 magnification. I'll recommend three TCs and a cheap F35-70 zoom. Its optics are a bit better than the DA18-55 and you'll get a little more working room. And it has an aperture ring. Trying for extreme macro with your 70-200 will require a LOT of extension; it gets unwieldy. If you intend to use that long zoom, consider getting a Raynox DCR-250, which is a corrected +8 dioptre closeup adapter with a working distance of about 5in / 127mm. *Magnification = FD/1000** where F= lens focal length and D= adapter dioptre. So at 200mm, M= (200*8)/1000= 1.6:1. The Raynox doesn't eat light as does extension (tubes-TCs-bellows). And you retain both aperture control and autofocus, for what that's worth (which ain't much!)

10-25-2011, 01:37 AM	#7
Philoslothical Veteran Member Join Date: May 2011 Posts: 1,889	I have a strong preference for primes when using tubes. They're much more predictable and tend to give better IQ. I've experimented with extension on all my lenses, and found some zooms simply don't cooperate, the focal distance is so close to the front element that you bump your subject (not good if it's alive!). Using diopter lenses on the end of a zoom can be effective though, with the usual caveats about loss of sharpness on edges.

10-25-2011, 02:55 AM	#8
RioRico Veteran Member Join Date: Jun 2008 Location: Limbo, California Posts: 11,263	Originally posted by Philoslothical I have a strong preference for primes when using tubes. They're much more predictable and tend to give better IQ. I've experimented with extension on all my lenses, and found some zooms simply don't cooperate, the focal distance is so close to the front element that you bump your subject (not good if it's alive!). Using diopter lenses on the end of a zoom can be effective though, with the usual caveats about loss of sharpness on edges. Indeed. The Raynox or even cheap uncorrected +dioptre meniscus closeup adapters can be good-to-great when image edges aren't critical. And primes are better than zooms on extension. OP asked about options for his current (zoom) lenses, and extreme macro, and I commented accordingly. For other options I'll of course point to https://www.pentaxforums.com/forums/pentax-lens-articles/152336-cheap-macro-b...lose-work.html How to get to extreme (and sharp) macro without spending a lot: * A good flatfield lens (Industar-50/3.5 or some short enlarger lens) and lots of extension (tubes and/or bellows) * Reverse-stacking disparate MF primes -- flip a 25mm lens onto a 200mm lens for 8x magnification! Other than microscopy, those are the most extreme options.

10-25-2011, 03:33 AM	#9
Mike Cash Veteran Member Join Date: Jan 2007 Location: Japan Photos: Gallery Posts: 6,950	I use genuine Asahi Optical extension tubes made in about 1962 for the old S2 film body (pre-Spotmatic). They work just fine.

10-25-2011, 06:43 PM	#10
canoetripper New Member Join Date: Oct 2011 Photos: Gallery Posts: 18 Original Poster	Wow--thanks for the great info, everyone! I'm feeling better about the K-5 for macro, and I'm looking forward to trying some of your solutions!

10-26-2011, 03:23 AM	#11
rod_grant Site Supporter Join Date: Apr 2010 Location: Wangaratta, Victoria Photos: Gallery Posts: 6,951	I remember seeing auto tubes for Pentax on a Polish site (@ around $70-75 AUST from memory) but I can't find them now. Perhaps someone else can help? - The universal camera; designed in Japan (we assume), assembled in Philipines, lens assembled in Vietnam, extension tubes made in Poland!

10-26-2011, 08:27 AM	#12
fs999 Loyal Site Supporter Join Date: Jul 2008 Location: Luxembourg Photos: Gallery Posts: 8,635	The best close-up is Hoya Pro1D Close Up N°3. I use it with my 200mm and 50-135mm. Excellent but not cheap...

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