The original:

Original as photographed

The final after editing curves in LAB mode:

Final as edited in LAB mode

Since I enabled the History Log in Photoshop (CS2), I’m adding that as reference here. For a quick recap, after converting to LAB mode, I cancelled out of Image>Adjustments>Threshold to not make any changes, but to determine that darkest and lightest points on the photo. Then  I increased the slope of the curves in the Lightness channel around my face so as to make it pop out of the shadow, and adjusted both the a and b channels to bring out both the turbulent green waves and the calmer blue troughs. After an Unsharp Mask on the Lightness Channel and a conversion back to RGB, I completed a brightness/contrast adjustment, saved and voila.

2009-12-06 20:53:08 File IMG_2043.jpg opened
Convert Mode
To: Lab color mode
Curves
Curves
Adjustment: curves adjustment list
curves adjustment
Channel: lightness channel
Curve: point list
point: 0, 0
point: 22, 37
point: 39, 70
point: 88, 115
point: 255, 255
curves adjustment
Channel: a channel
Curve: point list
point: 13, 0
point: 238, 255
curves adjustment
Channel: b channel
Curve: point list
point: 14, 0
point: 239, 255
Select lightness channel
Show a channel, b channel
Unsharp Mask
Unsharp Mask
Amount: 206%
Radius: 1.2 pixels
Threshold: 76
RGB Color
Convert Mode
To: RGB color mode
Brightness/Contrast
Brightness/Contrast
Brightness: 10
Contrast: 7
Save
As: JPEG
Quality: 12
Matte: none

Since all my sports photos will be manual and b/w, I’m not sure how extensively I’ll use LAB mode, but it is fun to play with.

When I first started looking at the color space, I quickly became aware that many of the filters were grayed out and unusable in the color space. Today, I found out that if I go to the channels tab, and select the Placed this channel, the filters come back full force. The differences between using a filter on the Lightness channel and Lab Mode and using a filter regularly in RGB Mode are slight. But to my eye, I prefer the Lightness channel. What do you prefer? (You can also apply filters to the a and b channels, but these bring on strong color alterations.)

For today’s post on my second blog, temporarily called Visual Snoopin’, I chose an old photo of some sweet peppers from my garden in 2006. I wanted to spice it up a little bit, so I decided to apply a filter. And then I found that I could use filters in the Lightness channel in Lab Mode.

Below, I’ve posted examples of the difference between using filters on the Lightness channel in Lab Mode (Left) and RGB Mode (Right). You can view my final selection at Visual Snoopin’ if you wish.

lab bas relief	rgb bas relief
lab chrome	rgb chrome
lab dark	rgb dark
lab diffuse (full size at Visual Snoopin’)	rgb diffuse
lab glow	rgb glow
lab ink	rgb ink
lab knife	rgb knife
lab pencils	rgb pencils
lab plastic	rgb plastic
lab poster	rgb poster
lab sponge	rgb sponge
lab under	rgb under