RB67 CDS v Plain Prisms

[nyoung]

I'm wanting to add a prism to my bargain basement RB67 kit based on a Pro SD body.
At KEH I can have a CDS prism with a non-working meter for less than $50 or a plain prism for just over $100. I have never used an in camera meter in MF any way so metering is not an issue.
Is there any reason that the cheaper (non-working) CDS prism would be inferior to the meterless plain prism?

 

[archphoto]

If it is not much bigger than the plain one an you don't mind...... why not get the cheaper one.
The issue is that selling a "broken" prism, even if the meter is broken and not the optics, is harder to sell than a full working one.
Try to check-out why the meter does not work: if it has fallen it could have damaged the optics aswell.

 

[Marco Gilardetti]

I never made a direct side-by-side comparison with the RB67 specifically, but generally speaking metered prisms show a darker image than non-metered ones. Try both in the shop before taking your decision.

 

[nyoung]

I sort of suspected that there could be a difference in brightness or even angle of view which was the reason I posted the question.

 

[Marco Gilardetti]

Yes, that's correct too, sometimes even coverage is smaller with CdS than with plain prisms.

Again, though, I didn't experienced this personally with the RB67 as the prism is so huge and heavy that I never really wanted to own one. But with other cameras, you could clearly tell that the viewing performance with the CdS-less prism was much better.