Beginner Extension tubes question's.

Orangecroc

Orangecroc

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My extension tubes have turned up, being my first, I don't entirely understand them.
My 70-300 lens doesn't seem to have a switch for MF and doesn't have AF on my body. As a result it seems I have to set manual focus before connecting to the tubes because it locks the focus ring when connected. What is the best way to focus with this setup?

My other lenses allow AF and have a MF switch, so that is not a problem with those.

I understand the DoF is significantly narrowed with a shorter MFD, so closing the aperture is necessary a lot of the time, are there other methods of lighting that don't rely on flash and flash syncing I could try when handholding indoors and outdoors so I can keep the SS up to reduce camera shake at the increased magnification?

Any other advice I haven't thought of would be much appreciated too.
 
If you cant AF with the tubes then going into "M" mode is your only option I guess.
With a flash its normally 1/250 max and any Aperture you like and W/B also but you know this.
Its strange that some lens allow you to use ext tubes with AF and some dont.
 
Are those basic tubes with no electronic connections?

What camera/lens are you using?
 
Graham said:
If you cant AF with the tubes then going into "M" mode is your only option I guess.
With a flash its normally 1/250 max and any Aperture you like and W/B also but you know this.
Its strange that some lens allow you to use ext tubes with AF and some dont.
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alfbranch said:
Are those basic tubes with no electronic connections?

What camera/lens are you using?
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The Body is a nikon D5200, the tubes have the electronic connections, so the AF-S lenses work with AF. My 70-300mm is just and AF model, I believe a screw driven AF. The aperture settings all transfer from the lens. There is not switch on the lens to change it to MF though, and for some reason the focus ring gets locked when attached to the extension tubes.
 
Orangecroc said:
The Body is a nikon D5200, the tubes have the electronic connections, so the AF-S lenses work with AF. My 70-300mm is just and AF model, I believe a screw driven AF. The aperture settings all transfer from the lens. There is not switch on the lens to change it to MF though, and for some reason the focus ring gets locked when attached to the extension tubes.
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Some Nikon user may answer this better but the lens may need an in body motor for focus and may not be connected,
 
Turns out the latch/release button on the extension tubes locks the focus ring when it's set to AF, as this is all the time with my 70-300 I just have to press the release while adjusting the focus, then when I am done it locks it again. Very odd, but at least I don't have to keep removing the lens just to adjust the focus ring.
 
Orangecroc said:
Turns out the latch/release button on the extension tubes locks the focus ring when it's set to AF, as this is all the time with my 70-300 I just have to press the release while adjusting the focus, then when I am done it locks it again. Very odd, but at least I don't have to keep removing the lens just to adjust the focus ring.
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Sounds like you are mounting the tubes wrong and the locking lever is engaging the AF drive screw. The blue arrow shows the drive screw, the red arrow shows where the lock should engage.

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sk66 said:
Sounds like you are mounting the tubes wrong and the locking lever is engaging the AF drive screw. The blue arrow shows the drive screw, the red arrow shows where the lock should engage.

View attachment 107515
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I'll have another look at it when I'm home. Surely the contacts for the electronic control of the aperture would be in the wrong place in this case and prevent me controlling aperture from the camera?
 
Orangecroc said:
I'll have another look at it when I'm home. Surely the contacts for the electronic control of the aperture would be in the wrong place in this case and prevent me controlling aperture from the camera?
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Probably, unless the tubes were manufactured wrong. But there's absolutely nothing else that can mechanically lock up the focus ring externally. And I've never seen or heard of a focus ring being locked up electronically.
 
sk66 said:
Probably, unless the tubes were manufactured wrong. But there's absolutely nothing else that can mechanically lock up the focus ring externally. And I've never seen or heard of a focus ring being locked up electronically.
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I'll check it out and see what is doing it. It's not a big issue as using it for macro I can lock it at MFD and just move or use the zoom ring.
 
sk66 said:
Probably, unless the tubes were manufactured wrong. But there's absolutely nothing else that can mechanically lock up the focus ring externally. And I've never seen or heard of a focus ring being locked up electronically.
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It appears that the extension tubes are compatible with screw drive AF, but as my camera doesn't have an in body motor to drive it, when I try to manual focus, the focus ring is trying to turn all the screws through the tubes. Because the body doesn't have it, there's no way to switch to manual. With my other lenses, there is not screw drive for the extension tubes to lock into and stop the focus ring.
 
Orangecroc said:
It appears that the extension tubes are compatible with screw drive AF, but as my camera doesn't have an in body motor to drive it, when I try to manual focus, the focus ring is trying to turn all the screws through the tubes. Because the body doesn't have it, there's no way to switch to manual. With my other lenses, there is not screw drive for the extension tubes to lock into and stop the focus ring.
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Ok, that makes *a little* more sense. Except that the "screw drives" in the lens/tubes are effectively just extension shafts and should spin freely when not being driven by the body (whether the body has a motor or not), so something along that path is jamming up when it shouldn't.

The problem here is that if you inadvertently turn/twist/bang the focus ring there is the potential for it to strip the internal focusing gears in the lens. And that will destroy all focus capabilities.

I'm guessing these were not expensive tubes... I would be inclined to take a dremel grinder to the end of the tubes's drive shafts to prevent them from coupling with the lens.
 
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sk66 said:
Ok, that makes *a little* more sense. Except that the "screw drives" in the lens/tubes are effectively just extension shafts and should spin freely when not being driven by the body (whether the body has a motor or not), so something along that path is jamming up when it shouldn't.

The problem here is that if you inadvertently turn/twist/bang the focus ring there is the potential for it to strip the internal focusing gears in the lens. And that will destroy all focus capabilities.

I'm guessing these were not expensive tubes... I would be inclined to take a dremel grinder to the end of the tubes's drive shafts to prevent them from coupling with the lens.
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Or send them back and buy different tubes.
 
Orangecroc said:
On further investigation it appears that the screw drive doesn't line up properly. I can live with pressing the release button to move the focus ring on this one lens. Everything works fine with all the other lenses.
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Well, seeing as how replacing the 70-300 AF-D would only cost about as much as a cheap set of tubes, I guess that's a reasonable risk to take.
After looking at a few pics of tubes like those, I bet you can just remove the one lens mount (lens side) and simply pull the drive pin out with very little hassle/risk. Just don't loose the latching pin/spring...
 
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N
sk66 said:
Well, seeing as how replacing the 70-300 AF-D would only cost about as much as a cheap set of tubes, I guess that's a reasonable risk to take.
After looking at a few pics of tubes like those, I bet you can just remove the one lens mount (lens side) and simply pull the drive pin out with very little hassle/risk. Just don't loose the latching pin/spring...
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It a bad idea. The tubes are only a stop gap until I get a macro lens anyway.
 
Orangecroc said:
N

It a bad idea. The tubes are only a stop gap until I get a macro lens anyway.
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As you get a macro lens and get used to it the tubes will fitted to it to get more magnification.
 
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