I have been using gouache for a little bit now and have tried three different types. Schmincke’s Designer and Horadam lines and Arteza’s 24 Set. All three types I use mostly dried from pans and while yes, using them fresh from the tube means you will have an easier time getting a good consistency for opacity, I absolutely get my paints (All three) to be opaque from my pans.

Mostly, Gouache should be watered down a little from the tube anyway to the consistency of cream and good gouache will still be opaque and vibrant then. When I use my dried gouache pans, I will spray them with water a few minutes before starting to paint (essentially, I pull out my paint box, spray liberally, then set up all the other supplies) and by the time I am really ready to paint, the pans have softened to a creamy consistency very similar to that of the tubes.

I use full pans on my main gouache set, giving me a nice, large surface area for my paint to soften. If I know I will need a larger amount of paint, I’ll drop water into the pans with either my brush or a pipette.

The ony time I will really pull out my tubes is if I need large areas of opaque colour (which I rarely do, since I paint comparatively small). That has nothing to do with the fact that I can’t get opacity from dried pans and everything with the fact that it’s just more convenient to squeeze out already ‘wet’ paint.

I think the whole discussion of gouache not being opaque when used from dried blobs comes from the fact that most people compare it to watercolour, where we can just dip a damp brush into the pan and have enough paint there to just start without much issue. Gouache just needs more time and water to reactivate. I guess that makes the time saving factor of using pans over tubes that we have in watercolour obsolete with gouache, but for me, my pans are still much more convenient than the tubes.