RB67 Pro-SD, 127mm question....

[Screwdriver]

Ok....got my RB67 from KEH today and feel like a dumbarse....35 years of photography :confused:

So the 127mm has three rings.....aperture, shutter and ?...What does the first ring at the front do? It has distance markings like focus. So what is the purpose?

 

[stradibarrius]

manual DOF.

 

[Screwdriver]

manual DOF.

Ok, so I am used to setting DOF with the aperture...so how is that ring different? What is the neutral point on the scale? Any manuals for that lens....did a search, but I got bupkus.

 

[unclemack]

It's just a depth-of-field indicator.
Some RB lenses have a floating element controlled by a similar ring but not the 127.
Eg. set the infinity mark to the right-hand f32 mark and the left-hand f32 mark is at a smidge over 10 feet/3meters so 10 feet to infinity is your DOF at f32.

 

[paul ron]

That front ring does nothing. It's a DOF reference calculator.

 

[Jeff Searust]

yup-- not a damn thing-- connected to nothing

 

[Screwdriver]

That front ring does nothing. It's a DOF reference calculator.

That's what I thought.....Damn Japanese, always adding stuff, just to add stuff.

 

[John Koehrer]

That's what I thought.....Damn Japanese, always adding stuff, just to add stuff.

Just like cupholders from Detroit.