Hi,
I tested split focusing screen with micro prism collar.
How did I get it:
I bought this k1000 screen from local vendor for ~18$, resized it to fit k10D. Used instruction from this link
K10D, new split focusing screen - a set on Flickr
So I have a diagonal split screen not exact 45 degree but around 30 degree.
I replaced this with my existing screen, for testing the accuracy of the screen i used it first with the kit lens, I used AF then looked carefully if the split was perfectly aligned, I retested the AF & split prism every thing was perfect.
Now I changed the lens to m42 55/f1.8 lens, focused manually using the prism when it was in perfect focus K10D gave a beep & hexagon was lit. I tried in many situations
and every time the focus confirmation was spot on, I am really impressed with this feature.
This makes manual focusing very easy.
On major issue is blackout of split screen, It depends more on situation bu normally you can easily focus up to f8, with the focus confirmation its easy up to f11.
So now I will come to my question, If we get the perfect focus confirmation beep & notification why should we require the new screen?
For me I own a lot of manual lenses so its helping me, but if you have only few manual lens you can continue with the original screen.
I would be adding pictures of my new screen later today. hope you like it