I've used a fine mist spray from a small medicine bottle I never used. Not only do I spray the palette, I occasionally spray the canvas. I'm not fond of the viscosity of the retarder, and IT dries and makes a skin, as well.

If you have a closable palette, a nice snap- shut one, or even a plastic tray with snap top, you can place your paint on a folded wax paper over folded wet paper towels to keep it moist. A friend keeps it in the fridge, says that works well.

If you spray the bottom of the container with aerosol Lysol, it doesn't smell mildewy. That goes for commercial covered palettes as well.

It some times is a task trying to keep my Acrylics plyable here on the High Desert of Arizona but I find that a small mister I got at my Eye Doctors Office when I got new Glasses works very well. Just the right amount of Moisture if you use a light pressure on the spray Head works very well. I too use one of the Masterson 12"X 20" Tight Sealing Lid Palettes.The Secret is to keep things damp,not moist too much. With less than 8% Humidity most of the time it becomes a problem to attain the proper mix of Paint and Moisture but it can be done. Next I am going to try H20 based Oils with Acrylics and see what happens.John

Just wanted to let you know that you cannot use water based oils with acrylic. The two are not mixable; however, you can use water soluable oils with traditional oils. I did three paintings recently with water mixable oils and used quick dry alkyd with water as a medium. I have done still life paintings and portraits with great results. You definitely should try the water mixable oils and experiment with them. It is important to keep the first layers thin, let painting dry, and apply next layer, and keep building up layers prior to using linseed oil. The "fat over lean" rule applies as it would with traditional oils.

Thanks for your response Phil.Painter. What I got is "Winsor@Newton Artisan Water -Mixable- Oil Colour Set, to try out. Not knowing any circumstances I originally intended to use over a dry Acrylic Base. You are telling me it will not work. Am I understanding you correctly?

You can certainly use Artisan oils over a dry acrylic base, but you can not mix them with acrylics.

I use both, and think they both have thier uses. However I am tending to use standard oils more and more as they just seem to have a better feel.