When you should use BlendIf instead of luminosity masks

One of the most powerful, but overlooked, tools in Photoshop is “BlendIf”. While luminosity masks offer dramatically more capability than BlendIf, it is still an incredibly useful tool in certain situations.

BlendIf offers a couple of substantial benefits:

  • It adds nothing to your file size. Zero. By comparison, a single luminosity mask increases the file size by roughly 1/3rd the size of the original image (because a luminosity mask is essentially a grayscale copy of the image). Using BlendIfs where you can reduces disk space, helps avoid the 4GB TIF file size limit, and lets you save images much faster (because they are smaller).
  • It creates a dynamic mask. If you ever make significant changes to your underlying layers (such as cloning out dust spots or some other distraction), you will likely need to update or replace your luminosity mask as well. BlendIf is constantly updated, which can save you a lot of work when you update underlying layers.

So when should you use BlendIf? Anytime it produces the same or good enough results. For the situations where BlendIf is as good as luminosity masks, it is well worth taking advantage of the benefits above. Of course, luminosity masks are much more capable in general, so the key is knowing when BlendIf is “good enough”.

Here are some previous tutorials I’ve created that show great uses for BlendIf:

If you have Lumenzia, be sure to see the BlendIf section in the written manual (in the ZIP download). In the CC panel, you can also click “?” and then the “Preview” dropdown to learn more about the BlendIf masks (be sure to see the “Technical Tutorial” for a very detailed overview of how it works).


Of course, these are just a few examples. You might consider using BlendIf for other uses like:

  • Dodging and burning specific tonal ranges (this is built into Lumenzia, just select the desired tonal range when you click “Dodge”).
  • Contrast enhancements for specific tonal ranges (this is also built into Lumenzia, just create the orange preview layers for the target tones, click “Contrast” and choose the option to convert to a BlendIf).
  • Applying noise reduction just to shadows. (In Lumenzia, use a D or D2 BlendIf).
  • Applying sharpening only to midtones or highlights (In Lumenzia, try a zone BlendIf or L).


Greg Benz Photography