Tuesday, January 22, 2008

Selective Color with Layers

Another request from the DPReview forum ... one that should make for a nice, short little article. How does one use layers to create a selective color image? It's actually pretty simple, once you get the hang of layer masks.

Let's use a small crop to make this quick and painless.

A black and white face with colored irises is desired. Step 1 is to create a black and white layer on top of the first. There is a small half white half black circle at the bottom of the CS3 layers palette, which you press to get a set of smart layers that can perform a specific image modification. In this case, select the black and white layer:

After playing with the dials a bit, a layer is added that looks like this:

The cursor is pointing to the layer mask, which we click into in order to mask out certain things on this layer. If we paint black into the layer, we reveal what is underneath (blocking this layer's content) ... if we paint white, we hide the layer beneath, showing the black and white version. If you make a mistake, simply switch colors and paint some more until you like what you see.

When painting, you actually paint right on the image, and the mask changes its value. This looks like:

It is best to zoom the image considerably and shrink the brush to a manageable size ... this makes it easy to stay in the lines.

Complete the painting of the iris, tweak contrast and do a bit of burning of the hair and you get something like this:

This can also be done with normal layers. Right click on the main (background) layer and select duplicate ... this creates a second normal layer that is opaque. Convert that layer to black and white using any number of techniques ... desaturate, channel mixer, black and white image command, LAB luminance channel, and so on.

Once you have the black and white layer on top, you only need a mask into which you can paint black to reveal the color beneath:

At this point, proceed as before, selecting the mask and then paining black over the iris. You end up in the same place.

Sunday, January 13, 2008

Windows XP support declining?

I rebuilt one of my older machines today and fired it up to reinstall Windows XP on it. I need this machine because Epson, in their rather infinite non-wisdom, have chosen only to support up to Vista 32 for my Perfection 1250Photo scanner. How hard would it have been to build one more driver for my Vista 64 machine?

Anyway ... the XP install went fine ... this is an Asus A8V motherboard with an Athlon FX60 dual core chip and 3GB DDR400 RAM. Nice system and reasonably fast. Once the system was installed, I started poking around with drivers and had the Radeon install fail wildly, looking for various bits like the .NET Framework 2.0 and such. But the driver did not fail all that gracefully. Neither did the motherboard drivers work too well. After a couple more installs, the system would freeze within a minute of booting.

I had to reboot 4 times before I could get enough time to find the recovery wizard and go back to the initial configuration. Thank you Microsoft for adding this capability. The machine was perfectly stable after the reboot. But I had to start over ... first the wireless card with its security key, then on to SP2, which will make all those crappy install work far better.

But wait ... Windows Update has changed significantly .... they want you to download and join the Microsoft Update party, with which I was already familiar from my Vista 64 experience. Well, fine. Off I go again into this new world ... and BOOM! ... fatal error. Microsoft cannot find the site you wanted or some such.

Apparently, to get SP2 you need Microsoft Update (I tried several avenues to download a legit copy of SP2, but all roads led back to the failing Microsoft Update.) But, to get Microsoft Update to work, you need SP2. I confirmed this by installing a version of SP2 they had shipped to me a long time ago ... and Microsoft Update works perfectly now.

The reason why I had wanted the latest SP2 was that Microsoft have been known to slip stream updates into different versions of their distributables. I just wanted to save myself a few restart cycles by getting all the latest stuff now. Oh well ... it looks like the B team are in charge of the XP portion of the Microsoft Update world ... and they managed to avoid testing this obvious scenario. Perhaps I am wrong and there is another way to get SP2 if you don't have a version on CD. But be warned ... if you have a functioning PC right now, consider downloading and saving a copy of SP2 onto a CD just in case you need to rebuild in the future.

Your mileage may vary.

Saturday, January 5, 2008

Lithium batteries are the new liquids ...

Traveling last year included the fun checking for toothpaste, hair gel, and anything else in which chemicals could be stored that might be combined to do harm to the flying public. This year we have a new threat, although not one linked to terror (at least, not from anything I've yet read.)

The new guidelines for Lithium-based batteries are that you can only carry certain sizes (pretty big, but you may need to prove they are acceptable) and you can only carry them in your carry on luggage. Also, they must be protected from shorting ... tape on the contacts, a baggy (yes, the primary weapon in your toothpaste and hair gel packaging arsenal returns) or even their original case (like anyone keeps those :-) ...

Rather than explain the intricacies, I'll now pass you to Thom Hogan's site, where he goes into a lot of depth on this in his news and comments section. It will either be on his front page at http://www.bythom.com or in his news archives at http://www.bythom.com/oldnews.htm.

Thom is a respected professional photographer and Nikon equipment reviewer who travels a ton ... he is also adept at distilling information down to that which matters. Read through his archives for some illuminating commentary on camera ownership ...