flash meter help required (minor)

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hangerhead

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I've managed to get a nice 2nd hand light meter (Minolta IV).

in my lounge here, with multiple bright ceiling spot lights only... (night time)
if i rest the meter on a shelf (next to an ornament for example, or even just in front of it) and e.g. change to ISO 500, f4, then i would get a meter reading of 1/30s.
when i take the picture though it appears to be under-exposed by around 1/2 stop or more.
I am just guessing here, but it 'looks' like the ceiling spot lighting is too strong only on the top of the dome...and so this is detecting too much light, even though the dome is directed exactly towards the camera lens...
So, if the ornament I am photographing has a flat front, it perhaps isn't catching light from directly above it as much as the dome on the light meter is.
rotating the meter so the dome is underneath or shaded slightly by the meter has the opposite effect of course, and introduces too much shadow.

does it/will it...work if i swap out the dome and instead use the fitting for the reflective metering system, but use the meter itself as an incident meter...i.e., since there is no dome to catch the ceiling lights as so strongly, would it instead be slightly more accurate?

however, in more even lighting, the readings appear to be much more accurate (at least when i remember to meter by not standing in the way of the incoming light and so blocking it).
 
so that would have to be a reflective reading?
or do you think putting the reflective attachment, but treating it still as an incident meter might help?
i've searched so many different sites for advice about this and can't find any.
 
It's a meter, not a magic wand. it can only measure the light that reaches it (is incident upon it) and it can't guess that the object you're photographing has a different shape to that of the incident dome. Like any other bit of kit, you need practice in using it, so that you can interpret the readings instead of just relying on them absolutely.

Basically, what the dome does is to accept light from an extremely wide angle. With all normal lighting and for all normal shaped subjects, that's fine, although sometimes it pays to point the meter at the camera, sometimes at the key light and sometimes at both and average the reading.

Before we had domes on incident meters we had flat sensors. They required more careful use but gave excellent results, and we still use them for flat subjects such as artwork, because they have about the same angle of acceptance as flat subjects and thereore automatically account for light losses caused by cosine law. I still use a flat sensor on my Minolta V (the one supplied with my Minolta 111) and it works perfectly.

All you need to do here is to shade the top of your sensor with your hand, to avoid a distorted reading from the unwanted top light - or just turn the top light off. Using the meter in reflected mode is the wrong approach, you'll lose the impartiality of the incident reading.
 
sorry if i didn't explain better,
i mean, i USE the meter, still as an incident meter, but instead of the dome, i attach the flat thingy that would normally be used for reflective metering.
i then re-meter (incident meter style) using the flat attachment thingy pointing back towards the camera.
 
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