Extension tube black-out (Page 2): That's what I said!!!! Junk. Any tool that don't work like it should ALL the time is junk.

Manglesphoto Loc: 70 miles south of St.Louis

tinusbum wrote:

i always used vello tubes,everyone was always saying kenko were the best and all others were inferior.i finally bought a set of kenko,they cost more but imo they were no better or worse than the vello.

That's what I said!!!! Junk. Any tool that don't work like it should ALL the time is junk.

RWR Loc: La Mesa, CA

Alan Wolslegel wrote:

Using a Tamron 90 mm on my D750 today all went well but when I put a Nikon PK-3 27.5 mm extension tube on the shutter sounded like it worked but the shots were black. The camera was set on f8 but the f-stop indicated was a right triangle next to F0. Is the camera incompatible with this tube or is something else going on? Your help is appreciated. Alan

The PK-3 ring has no mechanical aperture connection. You don’t say which Tamron you have, but you need a lens with an aperture ring. Put a G lens on the PK-3, the diaphragm will remain stopped down to its minimum aperture. That shouldn’t cause underexposure, though, unless you’re not metering through the lens.

Alan Wolslegel Loc: Thurston County, Washington

RWR wrote:

The PK-3 ring has no mechanical aperture connection. You don’t say which Tamron you have, but you need a lens with an aperture ring. Put a G lens on the PK-3, the diaphragm will remain stopped down to its minimum aperture. That shouldn’t cause underexposure, though, unless you’re not metering through the lens.

That’s the answer then, there is no aperture ring on my Di SP macro. Makes sense now that I think about it. Thank you.

RWR Loc: La Mesa, CA

I don’t know if the D750 will meter with no communication with a lens, but you can control the aperture with a FotodioX Vizelex Macro Helicoid tube. My Nikon-Nikon copy extends from 44.5-68.6mm. The actual f/stop is not given, but there is a red dot on the blue aperture control ring and reference marks on the tube. They may indicate 1-stop increments - I’ve not put an auto diaphragm lens on mine to check that.
You might also try lens stacking to gain more magnification. Have fun!

Alan Wolslegel Loc: Thurston County, Washington

RWR wrote:

I don’t know if the D750 will meter with no communication with a lens, but you can control the aperture with a FotodioX Vizelex Macro Helicoid tube. My Nikon-Nikon copy extends from 44.5-68.6mm. The actual f/stop is not given, but there is a red dot on the blue aperture control ring and reference marks on the tube. They may indicate 1-stop increments - I’ve not put an auto diaphragm lens on mine to check that.
You might also try lens stacking to gain more magnification. Have fun!

Thanks for sharing your knowledge. I ordered some macro filters to try with the lens but will look into the Helicoid tube also. 👍
Alan