Extentions

[Chocky]

 have a Nikon D80 camera
I have a plain Nikon AF Nikkor 70-300mm lens
I have a Sigma  dg APO Macro 70-300mm lens
I have a Tamron  LD Macro 70-300mm lens

I hav Kenko 2X extention and a Kenko 1.5X esxtention
The extensions work perfectly with the Plain Nikon Af lens  but when I use it with the  macro lanses (not on macro) the battery goes flat straight away.
Any one know why?
Please   

[BigAl]

My guess (and I stress it is only a guess) is that the non-Nikon lenses are shorting out the focus control pins.

Does any part get hot when this happens?

[Chocky]

Nope. I can shoot off one shot maybe two if lucky and the battery shows flat BUT I forgot to mention when I remove the extension and replace the lens  the battery is full again

It doesn't happen as I said with the Nikon Af and it won't work at all with the smaller LD nikon lenses but doesn't show a flat battery
Very mysterious

[Chocky]

It could be that on a LD lens there is not enough light for the TC converter estnsion and the camera thinks the battery is dead

[Seven_Wishes]

which version of the converter do you have, some of the older models exhibit the strange behaviour you have encountered when used with third party lenses and like Al suggested it is something to do with the contact pins and the way the lenses focus ... AF as opposed to AF-S lenses or visa versa .. definitely something to do with the contacts.

Just read this on the dpreview forum from a guy having the same problem with a D300 and a Sigma 70-300:
"Kenko made their Pro 300 TC's in two flavors: one that supports only the traditional screw-drive AF, and one that supports both AF and silent wave (AF-S). It looks like the AF-S TCs work while the screw-drive TC's don't."

[Chocky]

Mine is tha Kenko N-AFD 2X TELEPLUS MC4 and same with the 1.5 X

Won't work with the silent 18-55mm or the 55-200 SW NIKON lenses  or the DG  macro lenses but seams fine with the old plain NIKON AF NIKKOR

I can use it with the plai NKON 300 so will just stick to experimenting with it . A 400mm wil be a bit heavy  and very expensive

Thanks for you respons  


P.S. My teleplus "X 1.5X is for NIKON AFboth are DG

[RockArea]

My D80 does this occasionally when matched with my Tamron 18-270 lens. I think it is to do with the contact pins.

David

[Chocky]

Thanks David .
Yes, it probably is but it's not shorting

My Tamron is the same . Funny it had no efect on the battery this morning so it could be one of the batteires is a bit different.

Just looked the NIKON has silver  pins and the other two have gold. one came from the camera shop and the other from Duracell.

I'll have a go with the NIKON battery later. Now I have mixed them up and will have to recharge all of them

[RockArea]

On mine it seemed to do it with three batteries at different tmes. I didn't think there was shorting in any direct way, but obviously some functions were being affected.

[Chocky]

Yes. today one of the batteries didn't konc out

 When it did show empty as soon as I take the extension off and replace the lens the battery shows full
This didn't happen on the NIKON D50 but you did need to manually focus for it to work
I'll experiment later . I wonder if it's to do with light and the aperture.

My Sigma dg 70-300 is going back to the shop on Tuesday as it is shuddering and grating only a few months old.
My older one (same ) cost £79 to have it rebuilt. This new one is still under guarantee luckily

[Chocky]

Yep. Just tried all three batterires in daylightand they all show the flat symble . Soon as I switch back to just a lens thr battery is fine
I have the wrong version so will have to find a home for them

They do work with the plain AK NIKON 70-300 and didn't show flat batteris with the silent wave odinary lenses on the D80 but then it takes for ever to focus and you need to use them manually No good for action and birds in flight

Thanks every one for your  ideas and help