after I import my raw footage into 4.7 Pro, I want to filter out all of the night pictures, I see the dialog 'filter' with the luminance and hue and contrast, but I don't understand how to get out the nightpictures with this

Please check the instructions on http://lrtimelapse.com/workflow on the tab "long term workflow". That explains how to use the filters.
Let me know, if you have additional questions or anything remains unclear after reading that.

thank you, Gunther, I have and it did help, allthough there is still a lot that I have to learn.