Judging by how you talk I'll assume you've never done ANY street drug: No you will not hallucinate. Have I know you have maybe used LSD, shrooms, or any other psychadelic then I would say yes.
Your brain does not know how to produce a psychadelic experience on it's own, especially if it's never been "shown" how to do it before. People who have hallucinated before, have brains that can create experiences.
Next, is idoser powerful enough to make you lose reality and full blown hallucinate? No. but I am capable of some open eyed visual distortions. My hands change color and things just become different. NOT TRIPPING.
There are two types of visualsyou get with idoser. Closed eye visuals everyone can produce; you get them when your tired. They're blotchy, yet when you use idoser they get clear and make sense. Sometimes you can get into trances and they turn into "dreams". Thy are quite impressive sometimes.
Next, open eyed visuals. These were stated above, this is what people want to experience, open eyed stuff. They can't however. These are subtle, are much more real, and IMHO more fun because of the reality associated with them.
Auditory distortions. Well, idoser does this. Especially the first couple knute after you take your headphones off. It was not the dose that did it. Rather the sound from getting used to hearing the sounds, then not having them.
There is a lot of fun that can be had with the program. Just understand what it does. And what it is and is NOT capable of.