Rollei Hy6 light metering with waist-level finder

[Anaxagore]

Hi all, the 6008 and Hy6 have that rare possibility of light metering when using the waist-level finder. To do that, there is some compensation mechanism to "remove" the light coming from the viewfinder from that coming from the lens.

I have noticed quite a few times that when the sun is high in the sky, the camera goes to widest aperture and high times, although it should not. I remember having posted that question maybe 6 months to a year ago and the suggestion was to shine a light through the viewfinder to check for that possibility. I have not done that, but yesterday, when the camera showed parameters that would correspond to a very dark room, I shut down the viewfinder, keeping the camera in the same position. Then the exposure parameters went back to what they should be.
Is it possible that this compensation mechanism overcompensates? Or maybe I installed my viewfinder screen upside down and more light goes than what should go through the screen (that is the only optical reason I could come up with)?

 

[ic-racer]

I close the finder lid, or put my eye up to the magnifier to make a reading.

 

[itsdoable]

All the Rollei and Bronica waist level metering systems compensate by having an extra sensor in the mirror box, which reads the ambient light in the camera (ie: that leaking in from the waist level finder). The Rollei design has the cell facing the film plane, the Bronica design has the cell facing the focus screen. The main cells face forward in the mirror towards the lens, receiving light through a semi transparent area - which reads both light through the lens and leaking from the screen. The meter reading is the difference between the 2 sets of cells.

When the sun is entering in through the waist level finder, the ambient reading can be orders of magnitude larger than the ttl reading, which means the difference is mostly noise. The manual indicates that you should shade the waist level finder to maintain an accurate reading.

 

[Anaxagore]

So basically by closing the finder lid I was doing the right thing. Thanks for confirming me there is nothing wrong with my travel companion!