Nikon D40 and extension tubes

I've bought a cheap set of extension tubes on eBay to use with my
Nikon D40. There are no electronic connections but I thought they
would they would work on full aperture and manual focus.

All I'm getting is a warning 'Lens not conencted' and the shutter
won't fire at all. Is there some way they can be used on the D40, or
do I forget about them? Thanx!

 

are you in manual mode?

 

Whoops! No, I was in aperture priority. The shutter works okay in
manual mode, but now there's a new problem. The aperture closes down
when the lens is removed, and doesn't re-open when attached to the
tubes the way it does when attached to the camera body. There isn't
enough light to take most photos.

 

That's the behavior I'd expect when using a "G" lens with such
tubes. You can use your tubes on lenses with aperture rings, but
otherwise you're much better off with the current model Kenko tubes.

 

I got an ancient inexpensive short E2 extension ring (pre-Ai) with a
plunger for opening the aperture and a couple screws from the hardware
store let me make (inexact) aperture settings on G lenses when mounted
on a bellows. It's a kludge but makes the 105G macro usable.

 

Stock D40 lens + Extension Tubes

Sometimes you have to get creative (not to mention cheap) in order to move forward as a blossoming photographer. For instance when I first realized that extension tubes essentially left my stock D40 lens aperature closed, I decided to fashion a rod from a Papermate pen lid, and that's what I've been using for over a year now to keep the aperature open - it's used to displace the arm which usually connects to the camera without the tubes.

This method has worked out well for me, which you can see for yourself at my personal website www.gerbus.ca/photography. Most of the photos in the Macro section were taken with the pen-lid-rod / extension tube combo, using my Nikon D40 with stock lens.

Good luck everyone