I have for some time been wondering what pattern should be used for what display? I appreciate that this is likely to be a subject full of religion and prefences but here goes as far as I have been able to understand
Plasma: 10% windows 22%apl
DLP fvp: large 22APL
SXRD fvp: large 22APL
RPTV: large 22APL
With some LED sets (and LCD sets can follow the same guidelines) using window patterns gives dramatically lower Y readings than using fields, and the fields result is more consistent with the subjective brightness of the image. It's because of the dimming on some LED sets- when only a small area of the screen is lit, they dim the LEDs.
For that reason I would not recommend regular windows for them. I use full field on all LED/LCDs, though I imagine large APL windows might be OK also.
Also, some DLP and SXRDs have a dynamic iris. On the Mits DLP RPTVs sometimes it cannot be defeated. It is best to use large APL patterns on them.
Thanks for the reply, I will update the first post as we go along.
Regarding projectors and large apl patterns, I assume that is to avoid contamination of the readings. Are we looking at 25% windows or even larger?
Sorry for the confusion... I meant large as opposed to the small APL patterns on the AVS 709 disc. The reason is the small ones can cause problems with meter aiming in some situations, and I'm not sure if there is enough picture area to avoid LED dimming and/or iris closing.
im not sure we are misunderstanding each other at all, I think we are bot taking about window size, the reason I ask is because I want to create the patterns for the GCD disk, would 35% windows with a fixed 22%fixed APL be suitable?
and yes by contamination of the readings i was referring to fov.
Power-limited displays; CRT, Plasma, OLED: Square 1% Area patterns. (alternatively, 22% constant APL patterns though this would not be my choice)
Non-limited display types; LCD, DLP, SXRD: Full field patterns.
So this turned out as expected some facts and some religion.
My interest right now is mainly front view projectors .
For this I have been recommended both fields, windows and a larger window with APL. I was wondering if anyone have a set of mesusrements using different patterns?