In its most limited sense, modern, art would seem to concern itself only with the technical innovations of the period.
Edward HopperI use a retouching varnish which is made in France, Libert, and that's all the varnish I use.
Edward HopperYes, linseed oil. I used to use poppy oil, but I have heard that poppy oil is given to cracking pigment too, so I use it no longer.
Edward Hopper