Mamiya RZ67 Extension tubes

[danielscheel]

Hi everyone!

 

I have been shooting film for some months now and I love it! I own a Mamoya RZ67 Pro II and Sekkor 140mm.

 

I am focused on beauty photography and have looked into extension tubes and have found two of them, No1 and No2.

 

Which one should I get? No1, No2 or both?

 

Here is an example (closeups): Daniel Scheel | L´Officiel China

 

Also what light compensation do you need if you measure with digital camera?

 

Thanks and have a lovely day!

 

Kind regards,

 

Daniel

[orsetto]

It depends how close you would usually want to get. With your 140mm lens:

 

The No. 1 tube will let you focus to an area just under twice the size of the negative, say from the eyebrows to lips of your model, cropping some of her face.

 

The No. 2 tube will let you focus to an area slightly larger than the negative, say one eye and the nose, on one side of her face.

 

Both tubes used together would bring you close enough for just one eye and brow, but Mamiya specifically cautions using both tubes with the 140mm will give poor results due to vignetting. Since the tubes are very inexpensive nowadays, you could get both and try for yourself anyway- you might find the combined performance acceptable.

 

Mamiya advised photographers to use the exposure compensation table provided in the tube instruction manual, but no one ever does. Using the 140mm, compensation is typically +1.0 to +1.5 with the short tube, +1.5 to +2.0 with the longer tube, and +2.0 to +2.5 with both together. The info plate on the camera body will guide you: after metering and focusing, check the bellows extension number. At 0-20 use the smaller compensation, 20-40 use the larger compensation.

 

All the lenses from 127mm up give approx the same magnification as your 140. To get extremely close (2x magnification, or an area half the size of the negative), you need the 90mm lens and both tubes together. That combo will focus down to just one eye of your model.

 

Mamiya recommends these f/stops when lenses are used with tubes: f/11 with the short tube, f/16 with the long tube, and f/22 with both tubes together. Of course you can use wider settings, but there may be varying loss of sharpness and/or vignetting. You'll need to experiment to see which result you prefer.

Edited November 21, 2018 by orsetto

[peter_fowler]

^ "orsetto" what a great, thorough answer . So do you have any similar experience with the Pentacon 6 and it's extension tubes ?

Regards,Peter

[orsetto]

Sorry, peter_fowler, I've never used the Pentacon system so can't offer any assistance from first-hand experience.

 

There are a couple very useful and informative web pages dedicated to using the Pentacon/Practisix extension tubes: if you haven't seen these yet, have a look and I think you'll find everything you'd want to know:

 

An overview of all available Pentacon 6 extension tubes can be found here.

 

Exposure compensation recommendations for the automatic tubes used with 80mm Biometar can be found here

(scroll down to Table 2 labeled "Tubes With Plunger").

 

Like Nikon and Bronica, Pentacon initially offered a complicated set of six "dumb" empty screw-together tubes with no coupling to maintain lens diaphragm auto-stop-down. These can be painful to deal with, so I'd recommend looking for the later set of four "automatic" bayonet tubes that bridge the body auto-diaphragm pin to the lens. There was also a final, separate 10mm automatic tube that could be added to the standard four-tube set. This 10mm tube is especially handy for doing loose facial portraits with the 80mm (Hasselblad also added a 10mm tube some years after their first tubes, for the same reason). The No. 1 gets you a tight face portrait, the 2, 3, or 4 eventually get you to the eye + eyebrow.

 

Hope this helps!

Edited November 22, 2018 by orsetto

[peter_fowler]

^ Thanks for your reply , that's probably the only section of the Pentaconsix site that I skipped :) .

Best Regards,Peter