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Docrwm · 11-09-2010, 10:18 AM

I saw an Auto Extension Tube Set on eBay and it seems to indicate that it passes the Aperture setting through the set thereby facilitating metering. Anyone have any experience with these? The tube set I ordered is simply a static series of rings that move the lens away from the sensor but without any mechanical pass-through component.

Entropy · 11-09-2010, 10:54 AM

Originally posted by Docrwm

I saw an Auto Extension Tube Set on eBay and it seems to indicate that it passes the Aperture setting through the set thereby facilitating metering. Anyone have any experience with these? The tube set I ordered is simply a static series of rings that move the lens away from the sensor but without any mechanical pass-through component.

I have a set of these, I forget where I ordered them from and what brand though. (Not eBay, but I think they are no longer available. Auto tubes for K-mount seem to go in and out of manufacturing at random.)

Most eBay extensions I've seen were non-auto - Basically a K-mount to arbitrary threaded mount (for the tubes, which all had a threaded mount) back to a K mount.

Docrwm · 11-09-2010, 11:24 AM

Originally posted by Entropy

I have a set of these, I forget where I ordered them from and what brand though. (Not eBay, but I think they are no longer available. Auto tubes for K-mount seem to go in and out of manufacturing at random.)

Most eBay extensions I've seen were non-auto - Basically a K-mount to arbitrary threaded mount (for the tubes, which all had a threaded mount) back to a K mount.

These appear to be in good shape but are older. The box has "MiJ" on it and the tubes appear to be K-mount. I think I may try to snag them for $10 and see.

Ah well, sniped out from under me. Should never have mentioned it, I know better.

jolepp · 11-09-2010, 11:36 AM

For metering to work it should pass trough the electrical contacts and the aperture lever. Without the former the body won't consider it an A-lens or newer, without the latter the body cannot control the aperture.

SOldBear · 11-09-2010, 11:56 AM

"Auto" can means different things. Don't assume anything.

A jolepp said, to pass the aperture info, the extension tube needs to have electrical contacts on the mount.

Fl_Gulfer · 01-16-2011, 08:47 PM

Originally posted by SOldBear

"Auto" can means different things. Don't assume anything.

A jolepp said, to pass the aperture info, the extension tube needs to have electrical contacts on the mount.

I been looking for a set of these for 3 years.

SOldBear · 01-17-2011, 12:23 AM

Originally posted by Fl_Gulfer

I been looking for a set of these for 3 years.

Note the one on the right in the photo is not really an extension tube per se. It is a 2X teleconverter with the optics removed.

I have only one extension tube as the one on the left. But I have three copies of the one on the right.

IME, it's easier to look for a teleconverter than for an extension tube.

Fl_Gulfer · 01-17-2011, 01:49 PM

OK I have a 2x TC that I removed the optic's by just unscrewing it. I really want a set of Vivitar AT-22 or AT-23 ext tubes.

excanonfd · 01-18-2011, 02:06 AM

Only the AT-23 has the electrical contacts and give you the functional equivalent of an A series lens, AT-22 will function as same as an M series lens (shoot in M mode with green button for metering) with KAF2 mount bodies.

RXrenesis8 · 01-30-2011, 04:42 PM

I just got an A-22 set thinking it was an A-23 set. They have an aperture lever but I can't manually set any lenses aperture in-camera. As such all lenses without aperture controls on the lens itself always shoot wide-open. I guess older cameras could automatically set the aperture without any lens data?

**boriscleto** · 01-30-2011, 04:51 PM

Originally posted by RXrenesis8

I just got an A-22 set thinking it was an A-23 set. They have an aperture lever but I can't manually set any lenses aperture in-camera. As such all lenses without aperture controls on the lens itself always shoot wide-open. I guess older cameras could automatically set the aperture without any lens data?

Not exactly. "Non-crippled" K-mount cameras have an analog aperture coupler that passes non-A aperture data to the camera. "Crippled" K-mount cameras lack this aperture coupler which is why non-A lenses only work with stop-down metering.

Features and Operation of the crippled Kaf Mount

RXrenesis8 · 01-30-2011, 05:31 PM

I was wondering what that other lever was for!

Since the AT-23 passes data, metering should work with the crippled Kaf mount right?

**boriscleto** · 01-30-2011, 05:50 PM

Originally posted by RXrenesis8

I was wondering what that other lever was for!

Since the AT-23 passes data, metering should work with the crippled Kaf mount right?

Correct.

Fl_Gulfer · 01-31-2011, 03:10 PM

It's very hard to find a set of AT-23's . I was going to get a cheap Full Auto 1.4 TC for $85.00 and take the lens out but the guy said that the lens wouldn't unscrew like the manual 2x TC's.

RXrenesis8 · 01-31-2011, 11:04 PM

Mmm... I have a Tamron 2x auto TC (fun fact: it's a little less that 2x, maybe 1.9!) that I was trying to sacrifice for this purpose but as you mentioned it doesn't exactly screw out. There are a lot if tiny springs and levers in there to move around...

11-09-2010, 10:18 AM	#1
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	Auto Extension Tube Set I saw an Auto Extension Tube Set on eBay and it seems to indicate that it passes the Aperture setting through the set thereby facilitating metering. Anyone have any experience with these? The tube set I ordered is simply a static series of rings that move the lens away from the sensor but without any mechanical pass-through component.

11-09-2010, 11:24 AM	#3
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285 Original Poster	Originally posted by Entropy I have a set of these, I forget where I ordered them from and what brand though. (Not eBay, but I think they are no longer available. Auto tubes for K-mount seem to go in and out of manufacturing at random.) Most eBay extensions I've seen were non-auto - Basically a K-mount to arbitrary threaded mount (for the tubes, which all had a threaded mount) back to a K mount. These appear to be in good shape but are older. The box has "MiJ" on it and the tubes appear to be K-mount. I think I may try to snag them for $10 and see. Ah well, sniped out from under me. Should never have mentioned it, I know better. Last edited by Docrwm; 11-09-2010 at 01:15 PM.

01-31-2011, 03:10 PM	#14
Fl_Gulfer Veteran Member Join Date: Jul 2007 Location: Florida Gulfer Photos: Albums Posts: 3,054	It's very hard to find a set of AT-23's . I was going to get a cheap Full Auto 1.4 TC for $85.00 and take the lens out but the guy said that the lens wouldn't unscrew like the manual 2x TC's. Last edited by Fl_Gulfer; 01-31-2011 at 03:17 PM.

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11-09-2010, 10:54 AM	#2
Entropy Veteran Member Join Date: Jun 2007 Location: Owego, NY Posts: 976	Originally posted by Docrwm I saw an Auto Extension Tube Set on eBay and it seems to indicate that it passes the Aperture setting through the set thereby facilitating metering. Anyone have any experience with these? The tube set I ordered is simply a static series of rings that move the lens away from the sensor but without any mechanical pass-through component. I have a set of these, I forget where I ordered them from and what brand though. (Not eBay, but I think they are no longer available. Auto tubes for K-mount seem to go in and out of manufacturing at random.) Most eBay extensions I've seen were non-auto - Basically a K-mount to arbitrary threaded mount (for the tubes, which all had a threaded mount) back to a K mount.

11-09-2010, 11:36 AM	#4
jolepp Veteran Member Join Date: Oct 2010 Location: Finland Photos: Albums Posts: 3,196	For metering to work it should pass trough the electrical contacts and the aperture lever. Without the former the body won't consider it an A-lens or newer, without the latter the body cannot control the aperture.

11-09-2010, 11:56 AM	#5
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	"Auto" can means different things. Don't assume anything. A jolepp said, to pass the aperture info, the extension tube needs to have electrical contacts on the mount.

01-16-2011, 08:47 PM	#6
Fl_Gulfer Veteran Member Join Date: Jul 2007 Location: Florida Gulfer Photos: Albums Posts: 3,054	Originally posted by SOldBear "Auto" can means different things. Don't assume anything. A jolepp said, to pass the aperture info, the extension tube needs to have electrical contacts on the mount. I been looking for a set of these for 3 years.

01-17-2011, 12:23 AM	#7
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by Fl_Gulfer I been looking for a set of these for 3 years. Note the one on the right in the photo is not really an extension tube per se. It is a 2X teleconverter with the optics removed. I have only one extension tube as the one on the left. But I have three copies of the one on the right. IME, it's easier to look for a teleconverter than for an extension tube.

01-17-2011, 01:49 PM	#8
Fl_Gulfer Veteran Member Join Date: Jul 2007 Location: Florida Gulfer Photos: Albums Posts: 3,054	OK I have a 2x TC that I removed the optic's by just unscrewing it. I really want a set of Vivitar AT-22 or AT-23 ext tubes.

01-18-2011, 02:06 AM	#9
excanonfd Veteran Member Join Date: Jan 2010 Location: Vancouver, BC Posts: 1,421	Only the AT-23 has the electrical contacts and give you the functional equivalent of an A series lens, AT-22 will function as same as an M series lens (shoot in M mode with green button for metering) with KAF2 mount bodies.

01-30-2011, 04:42 PM	#10
RXrenesis8 Veteran Member Join Date: Jan 2011 Location: Orlando, FL (USA) Photos: Gallery \| Albums Posts: 523	I just got an A-22 set thinking it was an A-23 set. They have an aperture lever but I can't manually set any lenses aperture in-camera. As such all lenses without aperture controls on the lens itself always shoot wide-open. I guess older cameras could automatically set the aperture without any lens data?

01-30-2011, 04:51 PM	#11
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,477	Originally posted by RXrenesis8 I just got an A-22 set thinking it was an A-23 set. They have an aperture lever but I can't manually set any lenses aperture in-camera. As such all lenses without aperture controls on the lens itself always shoot wide-open. I guess older cameras could automatically set the aperture without any lens data? Not exactly. "Non-crippled" K-mount cameras have an analog aperture coupler that passes non-A aperture data to the camera. "Crippled" K-mount cameras lack this aperture coupler which is why non-A lenses only work with stop-down metering. Features and Operation of the crippled Kaf Mount

01-30-2011, 05:31 PM	#12
RXrenesis8 Veteran Member Join Date: Jan 2011 Location: Orlando, FL (USA) Photos: Gallery \| Albums Posts: 523	I was wondering what that other lever was for! Since the AT-23 passes data, metering should work with the crippled Kaf mount right?

01-30-2011, 05:50 PM	#13
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,477	Originally posted by RXrenesis8 I was wondering what that other lever was for! Since the AT-23 passes data, metering should work with the crippled Kaf mount right? Correct.

01-31-2011, 11:04 PM	#15
RXrenesis8 Veteran Member Join Date: Jan 2011 Location: Orlando, FL (USA) Photos: Gallery \| Albums Posts: 523	Mmm... I have a Tamron 2x auto TC (fun fact: it's a little less that 2x, maybe 1.9!) that I was trying to sacrifice for this purpose but as you mentioned it doesn't exactly screw out. There are a lot if tiny springs and levers in there to move around...