More details about the whole project:
The ghost image is there and you can see it in every scene where there is bright white object on black background. This means every start/end credits or very rare night scenes (watched the sin city without problems).
With higher contrast projectors it is an issue!!!
But here is for those who has ability to move your projectors:
I measured the size of the picture when the ghost image will sift to right so much that it can be removed totally with masking.
Details are: from 3m distance you need to project 62cm high and 146 wide image and they go over the screen. Of cource you need to finetune the prisms and stuff, but it works. You can now calculated your own distance from the screen and do the math.
The ghost image will become clearer with playing your projector zoom.
Look e.g. MIRAMAX logo. I can see the ghost image on right hand side (all depends which side your front prism is open, left or right). How close it is with the real logo, depends your zoom level and angle of the prisms.
So let me make clear. It is totally ghost free in the projected image with one precise setup. All others need to "suffer" it. For my projector it is not a problem. I will anyhow ignore at least the end credits, unless there is some joke coming up or some movie misstakes.
I could see the ghost image from ax200 with dynamic mode and only in the start/end credits or bond. With lamp mode cinema I had to really watch it.
So I really, really recommend these prisms to all the DIY people IF you have projector what is "bad" enough
When you really watch the movie you cannot see it. My earlier projector (panasonic ae300) had 2 dead pixels and I could see those from 4.5m away and the screen was only 200m wide and 114cm high. The knowing of the problem makes it worse. You will start to look that from every frame you can see. Same thing in the LCD TVs where you can see the rainbow problem.
This sounds like "Yes we can!" speech, but really the point is clear. Ghost is there permanently(except one setup), but you can live with it if you have low end projector and finetune the system enough.
Sorry about the long reply!