Cloudy, foggy, filmy, hazy, watermarks... whatever you call it, it's not what you want in your resin finish. It's called "Amine Blushing".
It occurs when there is humidity or slight moisture in the air or in an inclusion that you put in you resin. (flowers or insects that haven't completely dried)
It can also occur if you are curing in an environment that is too cold.
Basically - optimal resin working environment is room temperature and low-humidity.
How to prevent it:
Room temperature, approximately 72-77F
Anything below 85% relative humidity is fine, ideally between 50-60%,
Make sure that your resin is sealed properly in between uses, so moisture doesn't seep into the container.
No dips in temperature during the first 24hrs.
Using a fan heater in the Winter and a dehumidifier in warmer weather can help.
Before mixing another batch in a cold environment, you can try slightly warming the resin in a warm water bath first. (Note: this may shorten your work time.) Be aware as well, that using a hot torch in this environment can affect the resin as well.
Do not mix less than 1oz. of resin and hardener at a time. The exotherm nature will be reduced.
You can sand to remove the Amine Blushing and re-coat your project with resin or gently buff and polish with clear car wax.
