View Full Version : Grain Strain

D Akey
08-21-2006, 09:33 PM
I'm not quite certain about the settings for loading the grain.

If my grain is on a sheet 3000 x 2000, and I begin a new canvas. If I make the new canvas 3000 x 2000, would the grain be set to 100% if I wanted the grain to fill the canvas?

Is that the idea?


I've been experiencing cutoff with the marks. See attached pic. Any idea what's going on? Size of canvas is noted at about 3020x2400 with the brushes being set at 500%.

Oh, and the faint maks in the upper left is the felt marker, and no grain appeared. Also at 500%,

The grain was set to roughness=50, scale and opacity=100 No metal.

The grain worked in other pics at different settings.

There's also a strange thing in the little interactive thumbnail when loading grain. Sometimes is shows the grain stopping abruptly. in the middle of the swatch for no apparent reason. What does that indicate? Does it know there's going to be clipping in the brush?


D Akey
08-22-2006, 01:40 AM
This pic was a little bigger than the last, as you can see. But it shows what happened with the thumbnail as I changed the settings.

08-22-2006, 08:38 AM
To get better results with grain, use a bitmap that has higher contrast.
Paper grain relies on the variance of the grey-scale pixels of the grain image around the area of the brush as you're making a stroke.
If there's little or no variation around the area of the stroke, then grain has problems affecting the stroke.

Try to use grain images that have decent variation through dark and light colours. Best results are also attained if you use grain images that have more variation in smaller areas. Eg: a sand texture will give better results than a smooth white-to-black gradient over the grain image.

D Akey
08-22-2006, 11:31 AM
Thanks Andy!

I'll make my adjustments.

08-22-2006, 03:43 PM
Also note that 1::1 scaling of paper grain to output pixels is when the scale radial is at the 50% mark. Values in the top 50% of the radial scale the paper to be larger, and values below the 50% range scale the paper to be smaller.