Contax Aria Matrix Metering and Velvia

[bwcolor]

I'm guessing that at EI 50 (Velvia 50), when using a spot meter that Velvia will tollerate 1 1/2 stops over and 2 stops under. That doesn't leave much room for error. It has been years since I've done much slide film. How does this five area matrix metering work and where/when can it be relied upon, if at all when shooting slide film? In other words... am I dragging my spot meter everywhere I go when loaded with Velvia?

 

[tlitody]

you have a compensation dial if you find that the meter is not perfect for velvia and you have the ability to manually adjust film speed so spot meter should not be necessary. Besides the camera has spot metering albeit not 1 degree which you can check how good the matrix mode is for any subject. I think you will find the matrix metering pretty good anyway. But as always, it depends what you point it at as to just how good. No matrix metering system foolproof.

 

[bwcolor]

Perhaps, I'm really asking what the heck is the Contax matrix metering doing? I know that it takes in five zones. I assume a central then up, down, right and left. Then what goes on? I know what is going on when I use my spot meter, but I would love to approach things more casually much of the time.

 

[GSNfan]

@tildody: The matrix metering in Nikon SLRs is fool proof. F5 and F6 for example, even the cheap N80.

 

[tlitody]

Perhaps, I'm really asking what the heck is the Contax matrix metering doing? I know that it takes in five zones. I assume a central then up, down, right and left. Then what goes on?

any matrix metering is averaging but also trying to be clever and recognise what is dominant subject. What the exact algorythm is I have no idea.
The only way you are going to find out for sure is to try for yourself or are asking to determine if you want to buy an aria?

 

[tlitody]

@tildody: The matrix metering in Nikon SLRs is fool proof. F5 and F6 for example, even the cheap N80.

You mean its not possible to get an incorrectly exposed shot in matrix mode with these cameras ? Thats a rash statement if ever I heard one.

 

[bwcolor]

any matrix metering is averaging but also trying to be clever and recognise what is dominant subject. What the exact algorythm is I have no idea.
The only way you are going to find out for sure is to try for yourself or are asking to determine if you want to buy an aria?

No, I went Contax crazy this week. I picked up the Aria and an Rx and two lenses. It has been a while since I've been so excited about new (old) cameras. In fact, I spent my X100 money, so my back to digital will need to wait. These cameras clearly come from the same family as the G2. Wonderful cameras, but Velvia has me a bit scared. I shot one roll of Neopan 1600 @ 640 with harsh back lighting and the metering system figured things out and kept the subject right where it needed to be.

 

[GSNfan]

You mean its not possible to get an incorrectly exposed shot in matrix mode with these cameras ? Thats a rash statement if ever I heard one.

The only time you can screw the exposure is if you shoot directly at sunlight in aperture priority and not stop down the lens. Don't take my word for it, try it out yourself.

 

[splitimageview]

No need to be scared just because transparency film has less latitude.

Here is a good description of how a matrix meter works:

http://en.wikipedia.org/wiki/Metering_mode

 

[tlitody]

The only time you can screw the exposure is if you shoot directly at sunlight in aperture priority and not stop down the lens. Don't take my word for it, try it out yourself.

So its not foolproof then. That's what I said.

 

[bwcolor]

No need to be scared just because transparency film has less latitude.

Here is a good description of how a matrix meter works:

http://en.wikipedia.org/wiki/Metering_mode

Sorry, I didn't mean to indicate that I didn't know what matrix was. What I didn't know was what the Kyocera implementation of matrix involved. For example, does it use a data base to best guess? Does it weight areas based on some other algorithm...etc.?

I was hoping someone had some idea of their particular implementation and/or had shot with slide film under differing conditions and could report what worked and what didn't when shooting with the Aria in matrix mode.

 

[tlitody]

It used to be said that contax metering was biased towards transparency film. I don't know the truth of that and different transparency films have different scale so its impossible for any metering to get 100% all the time.
The aria is not auto focus and the lenses are not electronically linked to body so focus point is not in the aria matrix algorythm. But the aria has a good reputation for wide angle matrix metering.
Besides in camera metering is trying to place the exposure roughly in the middle of the films curve(based on film speed) so with a couple of practice rolls on varying lighting conditions you will know whether to use box speed or adjust 1/3 or 2/3 a stop either way from box speed for velvia 50. I think you will find only 1/3 stop would be required if at all.

 

[splitimageview]

As the wiki says, "Many manufacturers are less than open about the exact calculations used to determine the exposure."

From experience, I've always found the Aria's matrix setting to be more than accurate enough.

 

[bwcolor]

Yes, agreed.. I'm working a lot and will shoot some on Sunday in the backyard with differing conditions and try to get it back before vacation. That is why I'm asking. Next trip coming up..likely before the E6 comes back. Perhaps, the safest thing is to go spot this time and assume EI 50 and 1 1/2 over and 2 stops under.

 

[kdemas]

I've shot a fair amount of transparency with my Aria, G2 and N series equipment and matrix has worked beautifully. I'd do some testing of your own but I think you'll be pleased.

Best matrix, by far, is the F6 from my experience. That's one bright little gremlin in there 😉

 

[Rico]

Aria matrix metering has a clever feedback mechanism that might illuminate the algorithm. First, set Matrix metering mode. Second, set Manual exposure mode. The VF +- scale will now show the discrepancy between your EV and that calculated by the matrix algorithm. No need to burn frames and wait for results from the lab to discern the thoughts in that tiny Aria brain. 🙂

 

[tlitody]

Aria matrix metering has a clever feedback mechanism that might illuminate the algorithm. First, set Matrix metering mode. Second, set Manual exposure mode. The VF +- scale will now show the discrepancy between your EV and that calculated by the matrix algorithm. No need to burn frames and wait for results from the lab to discern the thoughts in that tiny Aria brain. 🙂

Well yes and since he has a spot meter he can easily take a spot reading of highlights and work out required exposure and then meter with matrix to see if there is any difference without using any film. But that won't tell you if exposure is correct for a particular film. It just tells you difference, if any, between manual and matrix metering. You do actually need to test the film in any camera to be sure for that particular camera that the results are optimum. They may be close but a 1/3 rd stop plus or minus might nail it or it may be fine with in camera matrix meter.

 

[oftheherd]

Yes, agreed.. I'm working a lot and will shoot some on Sunday in the backyard with differing conditions and try to get it back before vacation. That is why I'm asking. Next trip coming up..likely before the E6 comes back. Perhaps, the safest thing is to go spot this time and assume EI 50 and 1 1/2 over and 2 stops under.

I don't know that film that well, but 1 1/2 over and 2 under seems closer to what would be acceptable for color negative film.

Anyway, I am inclined to think that for most situations, you can just aim and accept the meter reading (and you will probably know from experience when not to). I used match needle over 30 years ago for most lighting situations with a Yashica TL Super, then auto exposure with a Fujica ST 901 for many years, and then a Contax 139Q. Used with all types of film including Kodachrome. In all but obviously tricky lighing, it worked well. I have a recently acquired Contax 167mt that has worked well with b/w and color negative using simple auto exposure.

I understand that doesn't specifically answer your question, but I think you don't really need to ask the question to be conficent in exposure for most lighting.

 

[bwcolor]

I don't know that film that well, but 1 1/2 over and 2 under seems closer to what would be acceptable for color negative film.

I pulled this off of a Velvia thread and it struck me that way also. In the old days I would usually use a higher EI when exposing slide film and the opposite with print. The spot meter is only of value if I know the latitude of the film.

 

[kbg32]

The metering in the Aria is pretty dead on. I have done long exposures with the Aria and was amazed how accurate the exposure was. Shoot a test roll and see what your camera's meter is doing, and take it from there. It's always good to shoot a test roll when getting a new camera. This way you can see if you have to add any +- exposure compensation.

Enjoy! They are great cameras and superb lenses.