Mamiya 645 F80 f/4 Macro Lens Function

[steckmeyer]

I have purchased used F80 macro lens for my 645. There is a ring on the front of the lens with two click stops and there is a red and green scale on the focus ring. I suspect these two are related. I’ve checked focus while changing the front ring position and cannot see any difference. What is the purpose of the front adjustment and how is it used? Thanks

 

[Jon Shiu]

Hello, it is so the scale is correct when you attach the accessory extension tube (allows 1:1).

Jon

 

[Imaginara]

thanx for that. have the same optics and been wondering that myself. Now where to get the extension tube (as i didn't get one with it

 

[Jon Shiu]

You can get one at keh.com or on ebay. It is called Auto Macro Spacer

Jon

 

[Greg_E]

Isn't that spacer the same as the auto macro tube #1? Or is there something special about the ube that is supposed to come with that lens?

 

[Jon Shiu]

The spacer is about 44mm of extension, so it is specifically matched to the 80mm macro lens. That said, if you don't need specific magnification ratios, you could use any combination of extension tubes to get closer focusing. It might be convenient to have the spacer to easily determine bellows factor with the focusing scales on the barrel of the lens.

Jon