lemme guess, your projecting onto a white bed-sheet in your garage
............ just kidding,
You didn't say whether you have an issue with peak white, like the really bright outdoor scenes seem dim, or just shadow detail, they're 2 different things.
What's your screen material and screen size? It's critical for CRT. For really punchy bright scenes, , you want a 1.3 gain, and IMO 80' wide horizontal max for an older ES focusing set. To squeeze a little more out of it, Dalite high power fabric is the only
high gain material that works with CRT.
If it's just dark scenes and shadow detail, you need some sort of gamma boost, HD fury makes an in-line dongle for RGBHV souces
if your using component video and transcoding that to RGB , then a rtc 2200
other choices also available on curt's forum, tell us your source material and we'll make suggestions.