JVC DLA-HD250 Brightness
Only one minor surprise here. The new JVC DLA-HD250 projector is very similar to last year's RS15, and the older still RS10 and RS1. In terms of brightness. In this case, the JVC DLA-HD250 - and, therefore also the JVC HD250Pro - measured a little brighter than most previous models (except for the RS1). That said, there haven't been really significant differences from year to year. The variations may well be due to the individual lamps, and the hours on the lamp. This year, we were the first to turn on the HD250 since we borrowed it from Tim, a nice guy who said I could use it, in exchange for us calibrating it, while his theater is still under contruction. (He's got it back now 8/2).
JVC DLA-HD250 Projector - Un-calibrated:
Lumen Output and Color Temp at 100 IRE (mid zoom):
Cinema 1= 801 @ 6934
Cinema 2= 743 @ 5942
Natural= 803 @ 6948
Stage= 865 @ 8036
Dynamic= 934 @ 9064
User 1, 2 or 3= 803 @ 6955
JVC DLA-HD250 Projector - Calibrated:
User 1 (Cinema 2): 758 lumens
User 2 (Dynamic): 853 lumens
The Effect of zoom lens positioning on brightness: Our standard measurements reported are done with the zoom at its mid-point. Here are relative numbers from the Cinema 1 mode, for different lens positioning From a percentage standpoint, the differences will be the same for any mode, as you change the lens angle:
Effect of zoom on lumen output (Dynamic mode):
Zoom out: 998
Mid-zoom: 934
Zoom in: 796
That works out to about a 7% increase in brightness going to wide-angle, in brightest mode, has the HD250 outputting a maximum of just under 1000 lumens (998) lumens. As you saw above, improving the overall Picture Quality, did lower the brightest mode to 853 lumens.
The Effect of low lamp (eco) mode on brightness:
Lumen Output (Low Lamp, Dynamic): 633
That's a drop from 934 - a whopping 32% and change, and fully consistant with last year's JVC review of the RS15.
That drop off should be the same, in any preset or custom mode when you drop the lamp power.
As noted the JVC HD250 (like the older RS15), you can also control brightness (and slightly effect contrast) by closing down the manual iris. The HD250 has only 3 steps, like the RS40, though, the highest end JVCs offer 16 steps.
Effect of Lens Aperture setting on lumen output (Dynamic mode):
Setting:
3 (maximum opening) = 934
2 = 713
1 (minimum opening) = 487
As you can see, setting #1 gives up about half the brightness, which also will slightly improve contrast.