Apprcach for manual shooting

I have three questions about shooting manual (e.g. for weddings inside a church). First is process - do you tune your manual settings from AV? And if so, what do you set next (speed, ISO?).

Posters generally comment that shooting in manual provides for greater image consistency - but I find light conditions can change quite quickly (e.g. with bright light slanting in from windows but a couple of paces foward, the light is considerably less as the window light disappears). With AV, the camera automatically adjusts; but if you are shooting in manual, will not the significant light changes produce over- and under-exposed images?

Lastly, if you meter and then set your camera to the manual settings of choice, what metering mode do you use to ensure the best settings (e.g. evaluative would seem to compensate the best for variable light readings)?

Manual does provide for consistent exposures as long as the light is constant. If the light changes, your exposure needs to change. I mostly use manual but tend to fall back to Av if the light is changing rapidly. As far as choosing the correct exposure in manual, I start by making a best guess on the ISO, then choose the aperture for the desired DoF, then roll the shutter speed wheel to place the needle where I want it. If that results in an unacceptable shutter speed, I adjust the other parameters.

evaluative metering would probably be best in that case if that's what you're comfortable with and you just want to meter as you frame the shot. The other metering modes can work fine, but they often require "metering" off of a different object or surface to a certain level and then turn back to frame your shot. As in, if you know from a certain scene that the bright area should be say, +2, but you don't want it to blow out, then meter the known area to correct exposure, and the rest of the shot also falls in line.
It's a little more complicated but that's why I'd personally just use exposure compensation in evaluative for most cases.

As ambient light in part of a scene changes it doesn't always follow that the lighting falling on your subject will change. If that's the case Av mode may incorrectly darken your subject and you'd be better off with M. If the light on your subject is changing then you'd likely be better off with Av mode

Thanks for the thoughtful replies. I recently shot a wedding where there were large windows with light streaming in to the church in bands (reflecting the distancing between the windows). As the bride walked down the aisle, the light falling on her changed. Additionally, some sections of the church were beautifully lit by the natural light, but other sections were quite dark. I would really like to have the consistency of image that comes from a manual setting, but I don't think I could have worked manual in that scenario, so I was curious as to how the more experienced might approach the issue. Thanks again.

IMO, there is no perfect answer. Some people swear on incident meters. Some would only use a spot meter. Personally, I think you can use the in-camera meter IF you learn how to use it to get consistent results.

I use this 99% of the time: Need an exposure crutch?
Why?
Post #47

Learn what works for you 99% of the time. Bracket the other 1%.

I recently shot manual for my entire trip to Jackson Hole, first time for either. Really wasn't that hard, although I could see quickly changing light being pretty difficult (this is where knowing your camera really comes in handy). I used spot metering and exposed for the brightest light in the picture. Normally, everything else feel into place. AV is easier, but I thought manual was more accurate once I got to a computer.