OSLO is great. OSLO is horrible. In the hands of a craftsman, OSLO can do some amazing things. Unfortunately, in your hands, its primary product is cursing and an increase in blood pressure. So why bother with OSLO EDU when Zemax is all the rage? Personally, I have three reasons
You have downloaded and started OSLO, but unfortunately you have no idea what is going on. In desperation, you have tried reading the OSLO User Guide. You now realize that OSLO is a beast. You're hoping that the The Google will solve the problem, but, instead, you've ended up on this webpage.
When learning something new, I like to relate this to things that I already know. In this case, a simple ray-trace of an object through a single bi-convex lens. (If you don't know about concave & convex lenses, radius of curvature, index of refraction, then you should sort that out first. If you cannot do a simple paraxial ray trace by hand through one or two simple (thin) lenses, then check out the old Edmund's Brochure for a nice overview).
Start with the single-lens ray-trace tutorial below (the others don't exist yet)
© 2016 Prahl