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Thread: Extension Tube.!!

  1. #1
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    Extension Tube.!!

    Hi guys,
    Recently i bought Non-electronic,not branded Extension tube. i clicked some of the pics using tht tube. but as it is non-electronic item, it is not possible to control Aperture. So By default lens always works for very shallow DOF.

    Nebody knows how to control DOF in such a circumstances.??

  2. #2
    herbert's Avatar
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    Re: Extension Tube.!!

    Welcome to CiC. You may want to add your real name to your profile so people can address you correctly.

    Here's how you can change the aperture:

    Mount your lens on the camera (no extension tube).
    Select the aperture.
    Press the depth of field button. This will close the aperture.
    Turn off the camera. The aperture will stay closed since the lens has no power to open it.
    Unmount the lens, add the extension tube and your lens. You now have the lens stopped down.

    However, you still cannot change the aperture. It is just a different aperture. Focussing will also be harder with the darker image seen through the viewfinder. You may be ok if you have a new camera with a good high ISO live view mode.

    Alex

  3. #3

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    Re: Extension Tube.!!

    It also helps if we know in what general geographical area you live becuase advice can vary depending on where you live

    You could also consider using what were called Waterhouse Stops These could be lens cap[s] with various diameter holes drilled in them. Ideally the stop is inside the lens but can be outside if close to lens. With an automatic camera it doesn't matter unduely how accurate the holes are to any f/stop, just a 1/16 inch hole could be useful, use A, Av or M mode. If you get a slightly soft result it may be caused by diffraction, in which case drill out the hole a little bit larger. bearing in mind that when you get close in you have very little DoF which can be dissapointing for somebody new to big close-up work.

    A second solution is to find an older lens designed for non-automatic cameras which has an iris. The shorter the focal length the greater the magnification you will achieve with the tubes you bought. Your tube set is probably 55mm total so with a 50mm lens you will get close, a bit more than, to 'double extension' where the image is the same size as the subject. A longer lens will give you less though its narower Angle of View helps.
    This is the theory when using a lens set at infinity or without any focusing mechanism ... the focusing ability of the lens is effectively giving you more 'extension' even if the lens front doesn't move forward, most do.
    Last edited by jcuknz; 11th November 2012 at 07:32 PM.

  4. #4

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    Re: Extension Tube.!!

    On Nikon lenses, the diaphragm may be stopped down by moving the lever at the back of the lens. If that lever is held in position by some makeshift means, you can use it at the aperture that you stop it down to.

    Canon is a different rain-dance. The Canon lens may be stopped down on the camera with the DOF preview function and then removed.and attached to the extension.

    Other brands, I don't know.

    Nikon is easy to use with reversed lens, as you then have access to the stop-down lever.

    Also manual lenses mostly must be stopped down in the same way as Nikon lenses, but can then be controlled with the diaphragm ring.

  5. #5
    DanK's Avatar
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    Re: Extension Tube.!!

    If you are going to use tubes a fair amount, your best bet is to replace those with ones that have electrical contact. A common option is the Kenko set, which is what I use.

  6. #6
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    Re: Extension Tube.!!

    Quote Originally Posted by 76erss View Post
    Recently i bought Non-electronic,not branded Extension tube. i clicked some of the pics using tht tube. but as it is non-electronic item, it is not possible to control Aperture.

    Nebody knows how to control DOF in such a circumstances.??
    I'm not one for disconnecting the lens from the camera electronics. So I bought a Raynox DCR-250 which is an additional 3-element magnifier, comes with a fit-any-lens universal 52-67mm mounting adaptor. It's about 2X on my camera. They also make a lower power DCR-150 model. I tested mine against a few other devices and it was the best.

    Second-best was a 10-diopter ZYKKOR close-up "filter", a simple plano-convex lens. Unfortunately, like ordinary filters, you would need one for every lens thread size.

    With any form of magnification, DOF becomes an instant problem, varying as it does from next-to-nothing to not-much-more ;-)
    Last edited by xpatUSA; 11th November 2012 at 11:46 PM. Reason: getting old . . .

  7. #7
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    Re: Extension Tube.!!

    Quote Originally Posted by herbert View Post
    Welcome to CiC. You may want to add your real name to your profile so people can address you correctly.

    Here's how you can change the aperture:

    Mount your lens on the camera (no extension tube).
    Select the aperture.
    Press the depth of field button. This will close the aperture.
    Turn off the camera. The aperture will stay closed since the lens has no power to open it.
    Unmount the lens, add the extension tube and your lens. You now have the lens stopped down.

    However, you still cannot change the aperture. It is just a different aperture. Focussing will also be harder with the darker image seen through the viewfinder. You may be ok if you have a new camera with a good high ISO live view mode.

    Alex
    Thanks Herbert. but unfortunately my camera doesn't have DOF button. i am using Canon EOS 1100D/ T3.
    i

  8. #8
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    Re: Extension Tube.!!

    You can see the DoF on the 1100D like so:



    The Canon EOS 1100D (Rebel T3) is an affordable entry level DSLR which does not provide a dedicated button for the depth of field preview near the lens like the more expensive models, as the 550D. But in fact this function is available and can be configured to be activated with the “SET” button.

    For this you select in the setting “Custom Functions (C.FN)” in the menu, then go to position 8 for “C.Fn IV:Operation/Others • Assign SET button” and there you can change the function of the button from “0:Normal (disabled)” to “5: Depth-of-field preview”.

    Now you can press and hold the SET button in recording mode to close the lens aperture and evaluate the depth of field. This works with the optical viewfinder and also when using the preview (LiveView) on the display of the camera.
    Hope that helps

  9. #9
    William W's Avatar
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    Re: Extension Tube.!!

    Quote Originally Posted by 76erss View Post
    . . . unfortunately my camera doesn't have DOF button. i am using Canon EOS 1100D/ T3
    Yes it does.

    The 1100D is an oddment in the Canon line up and unlike it’s brother (the 1000D) it does NOT support a dedicated DoF preview button around the RH side of the Lens Mount (looking at the camera).

    HOWEVER, the 1100D does have DoF Preview and it is accessed via the Custom Functions.

    Specifically
    C.Fn IV "Operation / Others" - C.Fn–8 "Assign SET Button" [select] 5
    will place DoF control to the “Set” button, located on the rear of the camera.

    You should refer to the user manual for further information regarding the allocation and functionality of the Custom Functions.

    There are other methods of using Stop Down Aperture for EF and EF-S lenses when used on EOS Cameras, but by far the easiest is to use the DoF preview and remove the lens whilst DoF preview is engaged as was described by Alex.

    However, buying a set of extension tubes which have electronic connections would be in your best interest and 1000% easier than all this fiddling stopping down the aperture and removing and replacing the lens - and will be 10000% easier for focussing and far less eye-strain.

    I also would suggest the Kenko - Set of three Extension Tubes. But I advise that you get the SECOND SERIES of the ‘DG’ mount. The reason is these tubes will allow any EF-S lens to mount to them.

    These set of three tubes can be identified by the WHITE EF-S alignment mark, on the female side of the rings seen below, on the RH side of the picture:
    Extension Tube.!!

    WW

    PS - What's yer name?

    PPS - Anton posted similar whilst I was typing - Oh well - I'll leave it there now . . .
    Last edited by William W; 14th November 2012 at 12:07 AM. Reason: added PPS

  10. #10

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    Re: Extension Tube.!!

    Having just done a shoot a few days ago with a lens with the 'switch' I would suggest a couple of Waterhouse stops would be quicker and simpler than any of these wonderful systems people are writing about Unless one is working with a tripod the business of working a system, or adjusting a switch leads to the focus point moving away from where you want it very easilly.
    I like Ted's comment about DoF

  11. #11
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    Re: Extension Tube.!!

    Thanks a lot.!!..it helped to knw more abt my camera..!
    1 more Q. Do i have to remove lens without Turning OFF the camera???....i tried in both ways (with n without turning OFF) bt didnt get ne much difference in DOF.

  12. #12
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    Re: Extension Tube.!!

    Thank you William.!!!

    BTW my name is Rohan.!!

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