using my hand held meter?

I have a Gossen Luna Pro F that works like a champ. I have tested it against the meters in several of my cameras and it seems to be accurate.
My question is about using the reflective vs. incident reading.

When these two readings disagree which is better to use? Does it depend on the scene?

Very good question and am sure you will receive some good answers and I will be following along too. Here is what I have learned / been doing to date for your consideration. I have an older model Gossen Luna Pro with the sliding incident/spot readings features. I take a general incident reading to determine where the light is falling within the EV scale. Then, if the scene allows it, I will spot meter the darkest and lightest values. If these values all fall within 2 EV values each side my initial reading, then I know I can shoot away at the suggested aperture and speed and will most likely avoid blown out highlights and shapeless blacks. If after taking the initial EV value reading, I see that the darks or highlights fall beyond this 'bracket' on either side, then I know I have some decisions to make with respect to where I want to 'place' my values. Do I want to emphasize highlights ? Or do I want rich blacks? That sort of thing. I'll be curious to learn if others believe my approach is sound, but am finally getting desired results and I have a pretty good idea now ahead of time what the negative will look like in terms of density when I get back to my darkroom. Cheers.

Sharris, that is a great response and helps me. I hope some more folks will give some good advice too.

sharris' answer is a good one.

The important thing is to understand what you are actually measuring when you use each of the two methods.

In incident mode, you are actually measuring the light that illuminates your subject. If you follow the incident meter's suggestion, when you look at your developed negative later, shadows will come out with the density that will print as shadows, 18% gray will come out with the density that will print as 18% gray, and highlights will come out with the density that will print as highlights. If your scene has a wide range of reflectance, the incident reading will give you a negative that at least approximates what you want.

The problem that you will sometimes need to deal with is that film (and paper) have a more limited ability to deal with a range of brightness than your eye does. For that reason, you sometimes have to adjust exposure and/or adjust development to include everything you want in your negative in a form that is easily printable. Also, some times you are really only interested in part of the range (e.g. the highlights) and are willing to sacrifice the other end of the reflectance range. You use a meter in reflectance mode to measure how much light actually reflects off of that part of the subject, so as to inform yourself about how much you may need to adjust the exposure as compared to the incident meter's reading.

I also use a meter in reflectance mode when I cannot take a meter reading from the subject's position, and it is clear that a different amount of light is hitting the subject as compared to where I am.

It is probably an excellent idea for someone new to the metering game to take both incident and reflection readings for each subject, and then compare them. In that way you will gain experience on how different subjects affect reflectance readings. I use that experience whenever I'm using an in-camera meter, and need to consider how to adjust exposure to compensate for subject reflectance.

By the way, one of the best ways to build this type of experience is to shoot slide film, and take lots of notes, and project the slides. Properly processed slide film removes the issue of development variation from the equation, and due to its inherent narrow latitude, it really shows whether or not your (highlight) exposures are accurate. If you can expose slide film accurately, and understand the difference (extra latitude) that negative materials gives you, you are set .

Matt

The incident mode works pretty well if the subject brightness range isn't extreme and, when used consistently it produces repeatable results because it eliminates the "guesswork" of assigning zones. Bear in mind that (in theory) a reflected light reading from an 18% gray card (when held as indicated by Kodak's instructions) and an incident light reading made in the same light should be the same. Phil Davis' "Beyond the Zone System" provides some interesting information on the incident vs reflected light approach but it isn't light reading by any means. Without going into the controversy of 18% gray or 12% gray as a basis for meter calibration, the main thing to keep in mind is that the meter is designed to receive light from whatever acceptance angle it has and reproduce that as a "middle gray" density. When shooting hand-held I generally use an incident meter because I don't use different development times for roll-film. With sheet-film I rely on a spot meter and reflected readings because the (reflected) subject brightness range will dictate the development.

Use the incident all the time or sunny side f/16

If you were in a studio, would you take the reflected reading from where the camera is placed?

In the studio I would most likely use incident meter.

S Harris method works very well especially with Null type meters. Finding a true neutral gray can be a probem and taking an incident reading gives you a starting point .