Used gouache to fix oil painting, now cracking?
Dear WetCanvas users.
I am a complete newbie when it comes to painting, thus seeking the advice of some of you experienced WC users.
The thing is, I recently relocated overseas and had to re-frame a painting of mine afterwards. Unfortunately this led to some peeling of the paint, sort of resembling white drops/flecks all over the painting. I then set out to repair the damage and bought some gouache painting to use, which turned out quite well.
BUT, I have now encountered two problems of which the second is the worst:
1. When looking at the painting from an angle, the repairs look like matte blurs that seem darker in color. When looking at the picture from the front, the repairs aren't noticeable at all (unless standing right up close to it).
2. After about a month, the repaired areas started to crack and come off. I am unsure whether this is: 1. Due to having used gouache and not i.e. oil for the repairs. 2. Lack of fixation/varnish. 3. Due to climate change (I used to live in Hong Kong = hot, humid and aircondition. I now live in Sydney = dry, big changes in temperature and no aircondition).
I have red about different types of varnish/fixatives, but am afraid that it will ruin the picture, either by changing the colors or even worse, making the whole painting peel...
I assume the original painting is an oil painting or at least treated with some sort of varnish, as the paint cannot be affected with water and it has a quite glossy finish. It is painted on a canvas and it is pastel colored predominately in nude, light orange/yellow and green colors. The style is contemporary realism.
Any help would be much appreciated!