Projector on with completely black image slice


Any ideas why the projector would power on - albeit dimly - when I use an all black image for slice_1?

I am trying to not expose the first layer at all for a working curve print on a very fast resin (cures a film with less than 0.04 seconds exposure). Having any light at all on the first layer may be throwing the results off.

In the attached video, you will see a brief glow just after I start the print - then the subsequent flashes for the layers I actually want to expose.

PatternMode Working Cuver ver2 0, (260.8 KB)


I personally believe but 100% not sure. the projector led is always on when you start the print but all the DMD are positioned to reflect the light to a heat sink which you will see some light. the projector led never turns off unless there is no printing.


Correct, any time a layer is exposed, the projector turns on (it’s off between layers). The amount of light that gets through the DMD when you’re projecting all black is less than 0.00mw/cm^2 as measured by our radiometers, so for most purposes it’s effectively zero (it could theoretically be as high as 0.004, but you have bigger problems if that’s an issue).