Thank you for your kind reply. This makes good sense. Especially services like Netflix er quite often pixelated in darker scenes because of the relatively low bitrate in normal HD programs. Haven’t played with the 4K variant yet though. Only have an 1080 SXRD pj for now. Planning on getting a much more light capable pj than the current 1600 lumen Sony I have. How much light would you recommend for a 405cm screen width? Should this be in the 2000+ range?
I am not seeing that reply you are referring to for some reason, but I have been using a JVC DLA-X5900 / RS440 for a long while in my own 1:1 seating distance (3m / 10ft) / screen width (3,3m / 11ft) cinema, but I do use the 4K E-shift on that unit to avoid visible screen door. As such, the X-series JVC´s are great in my opinion, while the Epson LCD, even with E-shift activated, would work better at a 1,5x seating distance or somewhere in those whereabouts... The 4K native JVC´s or the Sony 4K´s would work fine on 1:1 in my opinion - at least in terms of screen door.
Then it’s certainly also a matter of content quality, I see Netflix was mentioned, and although their overall quality has improved over the years, I agree that low bandwidth material might often be an issue with low seating-to-screen widths ratios. One solution as such would be to use a masking frame, and mask your 2.40:1 native image down to a smaller (in width that is) 16:9 when using sources like Netflix. One issue in terms of Netflix specifically though, is their aspect ratio being neither 16:9 nor 2.40:1, but somewhere in between, so our 2.40:1 masking screens that uses a fixed width of the masking panels to keep cost down would not be "perfect". Still, the new JVC N-series (native 4K), for example, has a very nice, new feature now that allows for custom digital masking for each format chosen, so that you can clip off some of the pixels at each side of the image when masking to 16:9. I mean, other masking solutions with adjustable side masking would be more flexible in such regards, but also cost quite a bit more, so it´s all give and take - and in my opinion keeping it as simple as possible in terms of overall operations of the system is also an important factor (i.e. not having to adjust the masking for a bunch of formats all the time).
As for light output, a 4m wide screen is certainly a large one, so if you would want to hit HDR levels brightness it would require quite a lot of light. However, in my opinion that is, a proper tone mapping or outputting SDR converted HDR material, would compensate a whole lot for brightness requirements. We just did a 3,5m wide 2.40:1 screen at the Alcons Pro-Ribbon Immersive Experience at ISE in Amsterdam using a JVC DLA-N7 and a DCR lens. The N7 outputs about 1800 lumens while the DCR adds another 30% or so, so in total about 2300 lumens on that setup. It did look quite smashing as far as I am concerned, even at HDR, and we were using the new internal tone mapping system of the JVC for that purpose. However, the Panasonic UB420 / UB820 / UB9000 UHD players also has a very nice tone mapping system if your projector does not support it properly internally (which is the case for the 4K Sony projectors as far as I am concerned at least, i.e. they require external mapping...). MadVR and a PC is another option, even dynamic HDR support (frame-by-frame) being launched these days if using a PC as your source is acceptable...