Jessops KA auto extension tubes

I have come in to possession of a set of Jessops extension tubes with the all important A contacts.

They are boxed and look totally unused. I am guessing must be 20-30 years old and have the original price sticker of £69.99 on the box

2 questions:

1. Anybody know if they are any good?
2. Anybody any idea what they may be worth if I decide to sell them?

Thanks

Carl

I bought a set from jessops in the 1990's, if they are the same they will have chrome on the lens facing side and black on the camera facing side. They work fine with my film cameras but don't pass the A info on my digitals. The solution is to grind/rub off some of the black on the camera facing side to expose shiny metal, this needs to be done where the new pin has been added for digital, a quick search here or on the web should help to show where. Then it works fine, assuming they are the same design as mine...
I have no idea of value.
Walt

Hi Walt - sounds as if they are the same and now that you mention it - I do recall reading something about removing the paint on the forum some time in the past - thanks for that.

I would like to try them with my Sigma 105 macro - I have a manual exposure set but don't get along with them at all well.

Carl

Hi Carl, on a further point, I had read on the web that you needed to modify all 3 tubes however all I did was modify the smallest tube and always have that as the first tube connected to the camera. If you can't find any helpful photo's of the mod I can post a photo of my unprofessionally sand paper modified tube....

Thanks Walt - will have a look and may take you up on your kind offer.

Carl

There is a thread on here somewhere ... all about the mod.

If I remember correctly it was something to do with Mannesty.

As for value, they used to sell for around £100 but have dropped quite a bit lately. I have seen them offered for half that now.

I've got a set in a box with the original Jessops price label
of £69.99 which is around what they sell for now. Not bad
considering that they are no longer made.

'

I bought a set of these 2nd hand a couple of years ago and quickly discovered the black coating on the tubes prevented the circuit which determines Aperture from being completed. You need to maintain a conductive connection between the body of the lens and the camera, so rubbing off the coating on teh tubes to allow this foxes the problem.

I also bought some and scratched off the paint (on all 3 tubes). Gives me aperture readout and control now; however not sure that PTTL flash works brilliantly although haven't done exhaustive testing on this. Cleared a patch where a 7th contact would be counting away from the screw.
Andy