Correct Use of Range Mask?

[SeattleStarGazer]

I've followed several tutorials using Range Mask on linear images, but have had no luck getting it to do anything. None of the tutorials mention changing the Range Mask to Non-Linear as is done with Luminosity mask. Should the Range Mask be converted to non-linear and if so how?

Thanks!

Wayne

[RickS]

In a linear image the data values are mostly clumped down at the low end and it's difficult to separate them.  You may find it easier to build a mask with RangeSelection if you base it on a stretched copy of your linear image.  The output of RangeSelection is typically a binary mask so you don't usually need to "convert it to non-linear."

Cheers,
Rick.

[SeattleStarGazer]

Thanks! That's why the slider was nearly impossible to use with a non-stretched Lum, the values were too close together. Once I used a stretched
Lum, it worked much better.

Wayne