[This would be easier with pictures, but I don't believe we can embed images in our posts — can we?}
I've been experimenting with blur to simulate the “Glamor Glow” filter in Nik Software's Color Efex Pro. I applied blur to entire image, then used the Eraser — full strength set on Highlights only — over the entire image. Accidentally, I later used the Eraser again (full strength, HIghlights only) and discovered (using Color Overlay) that additional areas where affected. Using Eraser (same settings) again and again removed more and more of the blur to higher toned areas of the image. I thought no more would be removed because I had already removed it from the image's highlights.
This lead me to set up a test image (using another app) with vertical strips 240px wide each across the image from pure black on left to pure white on right. I imported to Aperture and applied blur at full strength to entire image. Then I started playing with the Eraser (full strength) set on Highlights. Going over and over the same areas with multiple applications I finally realized. Tried the same with midtones and then Shadows.
Finally is dawned on me. Aperture was not applying the changes to the Highlights of the “image” but rather the highlights of the “MASK!”
Imagine a mask as PhotoShop would display it. Aperture can do this when you select “Brush Strokes” under the gear wheel in the blur brush dialog box. When first applied the entire brush strokes image displays white, that is, applied to entire image. But if you Erase using only “Midtones” for example, you will see the middle “strips” (in my black to white image) have the blur removed the most and less on black and white areas of the image. However, additional applications of the Eraser (set to Midtones) will affect more and more “strips” with each application. The reason is that with each application the gray tones of the “MASK” (not the midtones of the image) are getting darker and darker. With enough applications of the Midtone Eraser the blur is removed from nearly all of the middle strips leaving only the pure black and pure white strips unaffected.
Wow — I just read this post and I'm sure I've confused most of you. If anyone is interested I can try to show examples on my SmugMug site.
The point is: when Aperture says shadow, mid tone, or highlights in the brush tool — at least when erasing an effect (like blur) it means the relative tone of the “mask” at any point in the process.
I'd be thankful for feedback on this, even if its to say “what in the world are you talking about?” Again, I'll post sample images if this is not clear.
Thanks.
Bill
I think I understand what you are getting at, although I had to read it several times and then go into Aperture and play with the brushes and go back and read your post again. I’m glad I read your post because I had forgotten that one can choose to brush in or out only highlights, mids or shadows. I use the brushes a lot, especially under the colour brick to brush in colour after making an adjustment there, usually reds or bright orange colour . (I find reds and oranges captured on the sensors of my Nikon cameras seem to blow out when properly exposing for skin tones.) I didn’t think that any of the Aperture brushes were cumulative in effect like in PS but it seems they can be somewhat in their own way when the brush is set to something other than ALL in the brush range pane.
How did you make out trying to simulate the Glamour Glow effect?
I'd much rather have a bottle in front of me than a frontal lobotomy.
Craig, thanks for your reply. Yes, it was difficult to explain what I was seeing in my tests. Didn’t have the benefit of “a picture is worth a thousand words.” My point was that (in my described test) erasing highlights only affected the lighter portions of the “mask” not the lighter portions of the image. Hopefully, you understood what I was saying.
The Glamor Glow simulation in Aperture wasn’t too bad. Worth playing around with (that is, applying Aperture’s Blur to just Shadow, Midtone and/or Highlights for different effects. However, it was not as good as what you get in Nik’s Color Effects Pro. But that is understandable. I’m sure their version uses much more sophisticated algorithms than I could duplicate with Aperture’s controls. In other words, Nik’s Glow is not just simple blurring (I think).