Extension tube question?

littledrawe · 03-27-2012, 05:10 PM

I was using my tokina 60-120mm lens to take some pictures of things I wanted to sell. I used the on camera flash because I was lazy but wanted to brighten things up. So, I was at 1/180s 400iso f11-f16. I wanted to reduce the minimum focus distance to get in a little closer so I broke out my extension tubes which I have never used before and put a section inbetween the camera and the lens and went back to taking pictures.
Now,on-camera flash aperture around f11-f16 1/180s and the first picture I took with the extension tubes was all white, totally blown out. I went to f22 and same thing. I closed the flash and sure enough it was under exposed but not horribly.
I've always heard that extension tubes add a stop or 2 (RioRico said they "eat light") so why would these pictures have been so much brighter after the extension tubes then before?

Here is a picture of the tubes if it helps

Chaos_Realm · 03-27-2012, 05:23 PM

what mode do you have your camera on?
I vaguely remember there is a mode that if it doesn't have contacts, then it shoots the lens wide-open. I dont have my camera near-by to check but it might be something to consider.

oliver939 · 03-27-2012, 05:25 PM

Hi Littledrawe,

Nice to see your post

I actually have exactly the same extension tubes, found second hands for few bucks recently, and also had trouble in making a proper macro picture.

I used a manual facus pentax 50mm /1.7 A lens for that, and I noticed that I can not set the aperture (manually on the lens or via the camera in Av mode) as required.

When mounting the tube on the lens, everything looks ok. Moving manually the small metallic "finger" (what's the name in english?) would trigger the diaphragm properly.

But when I mount the lens+ tube on the K5, while turning to fix it, I can see the diaphrag opening as wide as possible (so it sticks f1.7) and nothing can be done to close it.

I guess that what you have too, overexposure because your lens is actually opened at its maximum and not at the f16 value you set.

If somebody knows how to fix that

joe.penn · 03-27-2012, 05:27 PM

You need to "foil" the contacts of the body to enable stop down metering/shooting with those tubes. The reason why your snaps were blown out was because every snap was shot wide open...

Last edited by joe.penn; 03-27-2012 at 05:34 PM.

joe.penn · 03-27-2012, 05:32 PM

Searched for a reference for a pic but can't find one - when I say "foil", I mean "aluminum foil" - take a small piece and use to short the contacts on the body, put the foil on the contacts while you are attaching the extension tubes, once the extension tubes are attached the foil will short the contacts and the lens will "stop down" in hyper manual mode as it should.

FYR: You can always sand down the flange on the tubes to the bare metal, then you won't need the foil...

**mattt** · 03-27-2012, 05:40 PM

If the Tokina lens supports P-TTL / TTL metering you are probably finding that with the extension tube you must shoot in full manual. The classic tubes you have shown there do not support metering (no electrical connections to communicate to the camera body with. Given that the flash is extremely close, and in full manual mode the flash will default to 100% power you will need to use off camera flash, and activate it using a bounce card or similar. I've done similar on a number of occassions....

Shot with DA 21 Ltd on Asahi Pentax Extension Tube #1 with AF 540 FGZ camera Right at 1/4 power triggered with the pop up flash & bounce card.

**Lowell Goudge** · 03-27-2012, 06:22 PM

Unless you are using an *istD and a flash that supports TTL flash as opposed to P-TTL the are two things that will happen, the lens will not stop down and the flash will go at full power.

**monochrome** · 03-27-2012, 06:39 PM

Originally posted by Lowell Goudge

Unless you are using an *istD and a flash that supports TTL flash as opposed to P-TTL the are two things that will happen, the lens will not stop down and the flash will go at full power.

Just a quick question. If I want to do similar with a K10D and Pentax K Auto Extension Tubes (have the aperture lever) can I use an AF280T and shoot in TTL mode?

Philoslothical · 03-27-2012, 09:58 PM

Originally posted by joe.penn

FYR: You can always sand down the flange on the tubes to the bare metal, then you won't need the foil...

This works better for me. Less can go wrong, and it's permanent. Fine silica sandpaper is the way to go, just buff off the paint with it until you get a reliable contact. Be sure to clean the surfaces well before mounting it on your camera - I'd hate to get that fine paint dust on the sensor.

SOldBear · 03-27-2012, 11:03 PM

Originally posted by monochrome

Just a quick question. If I want to do similar with a K10D and Pentax K Auto Extension Tubes (have the aperture lever) can I use an AF280T and shoot in TTL mode?

K10D does not support TTL mode, with or without extension tubes.

The Pentax K Auto Extension Tubes don't have A contacts. You need a lens with aperture ring and set the aperture ring of the lens at a non-A setting (if A setting exists) and treat the lens + tube(s) combo as a manual lens.

Also, note that the actual aperture is not the setting of the aperture ring of the lens. The actual aperture is slower, how much slower depends on the length of the tube(s) and the focal length of the lens.

**Lowell Goudge** · 03-28-2012, 08:00 AM

Originally posted by monochrome

Just a quick question. If I want to do similar with a K10D and Pentax K Auto Extension Tubes (have the aperture lever) can I use an AF280T and shoot in TTL mode?

As SOldBear said, the K10D does not support TTL flash.

The only cameras that support TTL flash are the *istD series, but I am not sure about the DL .

There is a real confusion presently about "Auto Extension Tubes" because in the 1970's and early 1980's auto extension tubes and auto aperture referred to the aperture being held open for focusing and / or metering and stopping down to shoot. Auto extension tubes were ones that had the aperture activation lever integrated into them.

The camera body "Auto Aperture" or A setting on lenses came about later, and this is what confuses people. To use extension tubes and retain camera body controlled aperture you need KA mount extension tubes with contacts.

This is why I keep my *istD. In reality, there is not that much gained when doing macro between say 6 and 10MP but the ability to control flash is very important, and also as SOldBear noted, there can be some real exposure issues with macro, when adding extension tubes. In this application the older TTL metering works better because it works based upon the actual light hitting the sensor.

littledrawe · 03-29-2012, 10:57 PM

So, I need to get down to bare metal on the mount of the tubes to prevent the camera from defaulting to MAX aperture on every shot and by sanding the mount of the tubes the camera will shoot at the aperture I have the lens set at??

**Lowell Goudge** · 03-30-2012, 03:53 AM

Originally posted by littledrawe

So, I need to get down to bare metal on the mount of the tubes to prevent the camera from defaulting to MAX aperture on every shot and by sanding the mount of the tubes the camera will shoot at the aperture I have the lens set at??

No, this will not work. You need a pin in location 3 (3rd pin from the lens locking pin) to tell the camera it is an A lens, you will note that the body side contact is recessed. Then younwould need to drill the pattern in the extension tube to correspond to maximum and minimum aperture. The base of your lens is conducting, and will therefore short pin 7 giving you focus confirmation already

Unless you really know what to do, there is not an easy conversion to make this an auto aperture (I.e. A ) set of tubes. You are stuck with manual mode on the camera and manual flash calculations

Philoslothical · 03-30-2012, 10:54 AM

Lowell, he's not trying to get A series performance, he's trying to get proper stop down metering and M series performance when shooting (the lens should stop down briefly when taking the shot). You can see from the pic that he has "A type" tubes, as in mechanical aperture linkage. If it's not stopping down the lens to the aperture he sets on the lens when shooting, he needs to short the sixth contact so the camera knows a lens is attached. It's the same with the K-r, but it does contradict what someone said in another thread about their K-7. It can't hurt to try.

Thing is, it shouldn't be necessary for shooting, only for metering. So, maybe there's something else going on.

littledrawe · 03-30-2012, 12:55 PM

Originally posted by Philoslothical

Lowell, he's not trying to get A series performance, he's trying to get proper stop down metering and M series performance when shooting (the lens should stop down briefly when taking the shot).

I don't really want transform these and add contacts. I just don't want the camera to default to f2.5 on every shot.

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03-27-2012, 05:10 PM	#1
littledrawe Veteran Member Join Date: Jan 2010 Location: Red Rock Photos: Gallery \| Albums Posts: 2,514	Extension tube question? I was using my tokina 60-120mm lens to take some pictures of things I wanted to sell. I used the on camera flash because I was lazy but wanted to brighten things up. So, I was at 1/180s 400iso f11-f16. I wanted to reduce the minimum focus distance to get in a little closer so I broke out my extension tubes which I have never used before and put a section inbetween the camera and the lens and went back to taking pictures. Now,on-camera flash aperture around f11-f16 1/180s and the first picture I took with the extension tubes was all white, totally blown out. I went to f22 and same thing. I closed the flash and sure enough it was under exposed but not horribly. I've always heard that extension tubes add a stop or 2 (RioRico said they "eat light") so why would these pictures have been so much brighter after the extension tubes then before? Here is a picture of the tubes if it helps

03-27-2012, 05:23 PM	#2
Chaos_Realm Veteran Member Join Date: Feb 2011 Location: Melbourne, Australia Photos: Gallery \| Albums Posts: 1,251	what mode do you have your camera on? I vaguely remember there is a mode that if it doesn't have contacts, then it shoots the lens wide-open. I dont have my camera near-by to check but it might be something to consider.

03-27-2012, 05:25 PM	#3
oliver939 Senior Member Join Date: Dec 2009 Location: europe Posts: 156	Hi Littledrawe, Nice to see your post I actually have exactly the same extension tubes, found second hands for few bucks recently, and also had trouble in making a proper macro picture. I used a manual facus pentax 50mm /1.7 A lens for that, and I noticed that I can not set the aperture (manually on the lens or via the camera in Av mode) as required. When mounting the tube on the lens, everything looks ok. Moving manually the small metallic "finger" (what's the name in english?) would trigger the diaphragm properly. But when I mount the lens+ tube on the K5, while turning to fix it, I can see the diaphrag opening as wide as possible (so it sticks f1.7) and nothing can be done to close it. I guess that what you have too, overexposure because your lens is actually opened at its maximum and not at the f16 value you set. If somebody knows how to fix that

03-27-2012, 05:27 PM	#4
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	You need to "foil" the contacts of the body to enable stop down metering/shooting with those tubes. The reason why your snaps were blown out was because every snap was shot wide open... Last edited by joe.penn; 03-27-2012 at 05:34 PM.

03-27-2012, 05:32 PM	#5
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Searched for a reference for a pic but can't find one - when I say "foil", I mean "aluminum foil" - take a small piece and use to short the contacts on the body, put the foil on the contacts while you are attaching the extension tubes, once the extension tubes are attached the foil will short the contacts and the lens will "stop down" in hyper manual mode as it should. FYR: You can always sand down the flange on the tubes to the bare metal, then you won't need the foil...

03-27-2012, 05:40 PM	#6
mattt Site Supporter Join Date: Feb 2011 Location: Niagara Photos: Gallery \| Albums Posts: 3,907	If the Tokina lens supports P-TTL / TTL metering you are probably finding that with the extension tube you must shoot in full manual. The classic tubes you have shown there do not support metering (no electrical connections to communicate to the camera body with. Given that the flash is extremely close, and in full manual mode the flash will default to 100% power you will need to use off camera flash, and activate it using a bounce card or similar. I've done similar on a number of occassions.... Shot with DA 21 Ltd on Asahi Pentax Extension Tube #1 with AF 540 FGZ camera Right at 1/4 power triggered with the pop up flash & bounce card.

03-27-2012, 06:22 PM	#7
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888	Unless you are using an *istD and a flash that supports TTL flash as opposed to P-TTL the are two things that will happen, the lens will not stop down and the flash will go at full power.

03-27-2012, 06:39 PM	#8
monochrome Loyal Site Supporter Join Date: Mar 2008 Location: Working From Home Photos: Gallery \| Albums Posts: 26,276	Originally posted by Lowell Goudge Unless you are using an *istD and a flash that supports TTL flash as opposed to P-TTL the are two things that will happen, the lens will not stop down and the flash will go at full power. Just a quick question. If I want to do similar with a K10D and Pentax K Auto Extension Tubes (have the aperture lever) can I use an AF280T and shoot in TTL mode?

03-27-2012, 09:58 PM	#9
Philoslothical Veteran Member Join Date: May 2011 Posts: 1,889	Originally posted by joe.penn FYR: You can always sand down the flange on the tubes to the bare metal, then you won't need the foil... This works better for me. Less can go wrong, and it's permanent. Fine silica sandpaper is the way to go, just buff off the paint with it until you get a reliable contact. Be sure to clean the surfaces well before mounting it on your camera - I'd hate to get that fine paint dust on the sensor.

03-27-2012, 11:03 PM	#10
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by monochrome Just a quick question. If I want to do similar with a K10D and Pentax K Auto Extension Tubes (have the aperture lever) can I use an AF280T and shoot in TTL mode? K10D does not support TTL mode, with or without extension tubes. The Pentax K Auto Extension Tubes don't have A contacts. You need a lens with aperture ring and set the aperture ring of the lens at a non-A setting (if A setting exists) and treat the lens + tube(s) combo as a manual lens. Also, note that the actual aperture is not the setting of the aperture ring of the lens. The actual aperture is slower, how much slower depends on the length of the tube(s) and the focal length of the lens.

03-28-2012, 08:00 AM	#11
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888	Originally posted by monochrome Just a quick question. If I want to do similar with a K10D and Pentax K Auto Extension Tubes (have the aperture lever) can I use an AF280T and shoot in TTL mode? As SOldBear said, the K10D does not support TTL flash. The only cameras that support TTL flash are the istD series, but I am not sure about the DL . There is a real confusion presently about "Auto Extension Tubes" because in the 1970's and early 1980's auto extension tubes and auto aperture referred to the aperture being held open for focusing and / or metering and stopping down to shoot. Auto extension tubes were ones that had the aperture activation lever integrated into them. The camera body "Auto Aperture" or A setting on lenses came about later, and this is what confuses people. To use extension tubes and retain camera body controlled aperture you need KA mount extension tubes with contacts. This is why I keep my istD. In reality, there is not that much gained when doing macro between say 6 and 10MP but the ability to control flash is very important, and also as SOldBear noted, there can be some real exposure issues with macro, when adding extension tubes. In this application the older TTL metering works better because it works based upon the actual light hitting the sensor.

03-29-2012, 10:57 PM	#12
littledrawe Veteran Member Join Date: Jan 2010 Location: Red Rock Photos: Gallery \| Albums Posts: 2,514 Original Poster	So, I need to get down to bare metal on the mount of the tubes to prevent the camera from defaulting to MAX aperture on every shot and by sanding the mount of the tubes the camera will shoot at the aperture I have the lens set at??

03-30-2012, 03:53 AM	#13
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888	Originally posted by littledrawe So, I need to get down to bare metal on the mount of the tubes to prevent the camera from defaulting to MAX aperture on every shot and by sanding the mount of the tubes the camera will shoot at the aperture I have the lens set at?? No, this will not work. You need a pin in location 3 (3rd pin from the lens locking pin) to tell the camera it is an A lens, you will note that the body side contact is recessed. Then younwould need to drill the pattern in the extension tube to correspond to maximum and minimum aperture. The base of your lens is conducting, and will therefore short pin 7 giving you focus confirmation already Unless you really know what to do, there is not an easy conversion to make this an auto aperture (I.e. A ) set of tubes. You are stuck with manual mode on the camera and manual flash calculations

03-30-2012, 10:54 AM	#14
Philoslothical Veteran Member Join Date: May 2011 Posts: 1,889	Lowell, he's not trying to get A series performance, he's trying to get proper stop down metering and M series performance when shooting (the lens should stop down briefly when taking the shot). You can see from the pic that he has "A type" tubes, as in mechanical aperture linkage. If it's not stopping down the lens to the aperture he sets on the lens when shooting, he needs to short the sixth contact so the camera knows a lens is attached. It's the same with the K-r, but it does contradict what someone said in another thread about their K-7. It can't hurt to try. Thing is, it shouldn't be necessary for shooting, only for metering. So, maybe there's something else going on.

03-30-2012, 12:55 PM	#15
littledrawe Veteran Member Join Date: Jan 2010 Location: Red Rock Photos: Gallery \| Albums Posts: 2,514 Original Poster	Originally posted by Philoslothical Lowell, he's not trying to get A series performance, he's trying to get proper stop down metering and M series performance when shooting (the lens should stop down briefly when taking the shot). I don't really want transform these and add contacts. I just don't want the camera to default to f2.5 on every shot.