If there's a better place to do this, please, point me in the right direction. I thought it would be a good idea to try and keep track of all the crowdfunding efforts done by idols in order to produce a photobook or video. The only Japanese platform I'm currently familiar with is GREEN FUNDING, but I'm sure there are others. GREEN FUNDING even has an idol section, labeled "アイドル," at the bottom of their site, though they're not all actually listed in that category.
Currently open projects:
八嶋 乃々華1st写真集制作プロジェクト
三島奈津子 引退写真集制作プロジェクト
Currently open projects:
八嶋 乃々華1st写真集制作プロジェクト
三島奈津子 引退写真集制作プロジェクト