Fulldome Fisheye Len Projection Problem
I recently bought a fulldome fisheye lens and 5000 lumens Sanyo projector that I intend to project Stellarium in our 4m diameter inflatable dome. But the image produced is always partial, as in what we normally see on the computer screen when we turned on the software, not the whole sky. How do I project the whole sky? Is there any settings adjustments to be done? I already put it on fisheye mode, but to no avail. It seems my fisheye only acts like an ordinary projector lens. Please help. I already spent a lot to make this work, but no success yet.
If okay with you, I'll post here my report to the fisheye lens supplier, on why it won't work.
I include here two photos of screen shots from Stellarium, one is a portion of the sky in which we normally sees from the computer screen. Obviously, this is not what I wanted to see in the fisheye projection, because it does not show the entire sky and what is on the opposite side.
What I wanted to see is the second pic, the whole sky, that would fit on the entirety of the inside dome. The middle portion of the sky should be the overhead position, then the entire circle or margin is the horizon. If the lens produced this whole-sky image then we can adjust the position of the projector to fit in the entire dome. We can recognize that, and we would have done so if we saw the image looks so big that we have to “back off” so the projected image would sit squarely on the dome. I assume you will want the lens pointed upwards, so it can spill the light in all direction, thus, filling the entire dome with all-sky image.
But, what we saw is the first picture, only a portion of the entire sky. More accurately, what we see on the computer screen. This I tell you, is the limit of the image projected, it does NOT show the entire sky. And, if you agree with me, the farther back I go it will only make this portion of the sky bigger. It does not show the entire sky. And if I point the projector lens upwards, the horizon goes up too. That is a big difference. That is the problem.
That’s why, I ask if your engineer knows something about it. Maybe we need to adjust something inside the projector, or the lens, or the software we use Stellarium. May I ask you, if you have customers who had the same requirements as we do or we did, and please let us know what happened to them. Or, is there a scale system in the Stellarium software that let us minimize the image into a complete circle, so the entire thing fits exactly on the lens projection?
I think I’ve exhausted this report to the extent that we should now find a solution for this. In a sense, we know how to adjust the position of the projector and lens to try to make it work, these are common sense stuffs. We would not report this to you if the problem has not been this difficult.
We did changed resolution as my laptop does not work well if the resolution is not okay with the projector.