Mamiya 645 extension tubes

[Ulophot]

I'm looking for specs on the 3-tube set for the 645 line (I have the Pro but non-metered). That is, what are the new near focus ranges with, say, 80mm and/or 110mm lenses, and what are the required exposure increases? Thanks.

 

[MattKing]

This provides some of the answers.
If you find it of use, I'd recommend sending Mike Butkus his requested donation: https://www.cameramanuals.org/mamiya_pdf/mamiya_645_accessories.pdf

 

[wiltw]

Mamiya is pretty poor about providing information about their 3 extension tubes...all you know is length of tube, but no information found about min/max mag range for a specific FL of Mamiya lens. Not in camera owner manual, not apparently in any user sheet included with the extension tube,
not that I could find! They are not even mentioned as accessories available for your camera in the user manual.

Information for Bronica 645 extension tubes, to give you a rough idea...

• 14mm tube, 75mm lens 0.18 (at Infinity focus) -0.36X (at 0.6m focus)
• 28mm tube: 75mm lens 0.36-0.54X
• 42mm tube: 75mm lens 0.54-0.72X

 

[MattKing]

Here is the table from the Mamiya 645 Accessories brochure link I posted:

 

[Neil Grant]

...of course it depends on what your trying to photograph, but you might regard the number 1 tube as your 'go to' for the 80mm lens and the number 2 tube for the 110mm. Both tubes allow slightly closer focusing with the respective lenses. The tubes are unexpectedly tricky to attach and match up with correctly with lens 'coupling prong'. Especially the very thin number 1. Removing them again isn't pure joy either as the release tabs are very small. As an alternative to tubes on the 80/110mm standard lenses, the 80mm macro makes a good general purpose lens, efficiently getting down to 'close focus' unaided as well as maintaining greater distances and of course infinity. If you are regularly doing near distance work (neither the 80mm f2.8 nor 110mm f2.8 focus very close) the 80mm macro will be a whole lot less fuss.

 

[Ulophot]

...of course it depends on what your trying to photograph, but you might regard the number 1 tube as your 'go to' for the 80mm lens and the number 2 tube for the 110mm. Both tubes allow slightly closer focusing with the respective lenses. The tubes are unexpectedly tricky to attach and match up with correctly with lens 'coupling prong'. Especially the very thin number 1. Removing them again isn't pure joy either as the release tabs are very small. As an alternative to tubes on the 80/110mm standard lenses, the 80mm macro makes a good general purpose lens, efficiently getting down to 'close focus' unaided as well as maintaining greater distances and of course infinity. If you are regularly doing near distance work (neither the 80mm f2.8 nor 110mm f2.8 focus very close) the 80mm macro will be a whole lot less fuss.

Thanks for the tips. Buying a macro lens is not my interest, and, fortunately. a #1 tube just popped up this morning at KEH for about 1/3 or less than I have seen elsewhere. My portraiture is on hold as we get through the COVID problem, which is going to take a good while, so I'm making composition studies and find that a little bit closer focus often would be useful.