Keeping transparency in painting -- how?

[Richard Budig]

How do you go about keeping that sense of depth that one gets when keeping paint transparent?

I'm not so fortunate that I can hit my value/color dead-bang every time, so, as my painting proceeds, I find that I am constantly readjusting value/color relationships, which means that soon enough, I'm adding opaque colors to bring a value or color up, down, etc.

A painting without that sense of depth seems to lack something.

One idea I've considered it to paint my painting, and then, go back and put a glaze over it. If the painting is basically warm, a warm glaze would give that sense of luminosity, but then, the whole thing would be luminous -- right?

Part of the charm of a painting (it seems to me) is one that has those patches of deep, look-forever-into-it, and those patches of opaque places, especially in the lights.

I seem to be rambling, and I apologize. I'd like to hear from anyone who has found a way to achieve this mix of transparency and opaqueness.