Unity will allow me to use image effects in indie version.

Hello everyone! I've been using Unity3D for almost an year now and I've hardly ever experienced any problems. However, now I have encountered one that I feel like asking for help. So I've been working on my project as usual when I've noticed that Unity will allow me to use image effects (the only PRO ones) without giving me errors or whatsoever. It get's even more interesting. Unity will not allow me to use any other PRO features (dark skin or shadows for example). I must say that I am not using the 30 days PRO trial and I haven't used any cracks.

So I want to ask if I can use the image effects for my project or I should ignore them?