Looking for opinions on the AE prism for the Mamiya 645 Pro

My main and favorite camera by far is my Mamiya 645 Pro, which I primarily shoot with the 80mm f/1.9. I adore it. The one thing I wish I had to this day, though, was at least some basic metering. I meter using a handheld Sekonic incident meter, but if I could supplement that with in-camera reflective and the option of aperture-priority I think I would really like it.

However, I'm having a hard time digging up any actual user experience with the AE prism. Anyone here use it? Thoughts?

I have the previous version of this prism - the "N" model - which was originally designed for the Mamiya 645 Super. It works well on both my 645 Super and 645 Pro bodies. I am not sure whether the newer version of this prism, which is designed for the Pro, is backward compatible with the Super.

The prism is reasonably bright and reasonably light and small.

The metering is interesting - either centre-weighted averaging, spot, or automatic shifting between the two. The in-finder information is reasonably easy to see (although I don't where glasses).

The auto-exposure works reliably.

My only complaint is that is very hard to pin down what the measuring area is for the spot metering function.

Matt

I had both the N version and the Pro, for me they functioned the same, but the pro one sure looked cooler!

I don't know what the spot area is either, but it is like spot metering with most SLRs, kinda big to be considered really a spot. I mostly used the averaging and both prisms worked really well. The Pro one was pretty expensive three or four years ago. At the time the N version was about half the price, or something close to that, and might be an option if you are sensitive to the cost of the Pro version.

Thanks for the feedback. That's enough for me. I'll pick one up when I can. My business partner in Japan has a knack for finding used equipment there for cheap, so hopefully he can find something at an especially good price there for me.

Here is my opinion on it, not to sound negative or anything:

While a prism is great for this system, any reflected meter that measures a large area is a compromise, IMO. You may "really like it" from a convenience and a speed POV, but you may not "really like it" as far as results compared to an incident meter or carefully-used spot meter. What is wrong with continuing to use your Sekonic? You will save money and get better results. You only need to re meter when the light changes.

So, if having an in-camera meter is somehow worth the worse exposures you will get, which it may well be for what you shoot, then go for it.

Is there a plain-ol' prism for the '80s Mamiya 645s? (I don't know because I use the '70s ones.) You might want to look at that instead, and keep using your Sekonic.

I would just like the option of shooting aperture-priority in situations where I'm changing things a lot and in which reflective accuracy isn't going to be an issue. I love my Sekonics (508 and 358) but I do a lot of cycling photography and other things in which I don't always have time to meter, really, and settings from my last shot aren't necessarily going to be accurate. It's more about removing a weak point in my shooting setup for the work that I do than anything else. I'll always do incident metering manually when I can, but there are definitely situations when the AE option would be a lifesaver. I currently already have a non-metered prism on the body and love it, but just wish I had the extra capability of the metered one.

Edit: I should note that at one point I used a borrowed Pentax 645 for a little bit specifically to see about how useful the built-in metering would be, and a few days later I was quite convinced.