Glazing

[Michael Georges]

Patt:

Rubbing Garlic and Onion on paintings has been a practice for many hundreds of years. It is usually used when painting over a dry layer or a layer that is shiny or slick. The garlic or onion applied to the surface will eat into the paint layer a bit and help the adhesion of your subsequent layers.

As to your use of a Damar-based medium. Yes, the damar is what is causing the gloss to the finished work. Actually, it is a hallmark of many Dutch masters that their works are quite glossy and enamel like.

As to the streaking, I suspect it may be caused by the use of the onion and linseed combo. I would exercise care in spreading linseed directly into your painting as it has a tendency to yellow quite a bit over time and it takes forever to dry. I might suggest using a spray instead made of 9 parts rectified turpentine and 1 part stand oil. Apply your onion juice, let it sit for a couple of minutes and wipe it off with a cloth. Then spray this mixture onto the passage you will work on - wait about 3-5 minutes for the turps to evaporate off (ventilation please) and you will be left with a very thin coat of stand oil on the surface. This should mimic your linseed oil and allow you to paint wet into wet without the deliterious effects of the linseed and hopefully, and this is only my guess, it will help with the streaking.

As to your question about retouch varnish, most retouch varnishes are just Damar and Turp. I use them to seal my charcoals and as the first layer after my underpainting to bring the values up to true. I would only use it at the end of the painting if I were fairly confident that the layers underneath were mostly dry. The turp in the retouch will hasten the drying of the top layer, but middle and bottom layers may still be wet - cracking could occur when they fully dry. I recommend waiting at least 6 months before final varnishing. That said, I usually apply a thin coat of my medium to the finished painting to even out all of the areas and bring the gloss to a uniform sheen over the whole painting.

Again, these are just my opinions and my outright guesses in some areas, so take them for what they are. Hope it helps.