Archived posting to the Leica Users Group, 2010/04/28
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On Apr 28, 2010 at 07:05 PM -0700, Bob Adler wrote: > You can't edit with Camera Raw if it isn't a Raw file. You can certainly > do > non-destructive edits on a .tif file (using LR or CS# layers), but my > understanding is that a .tif file is created by software interpreting the > sensor output (either scan or camera). Go to the File>Open menu in Photoshop. Highlight your tif or jpeg. Change the Format popup menu to 'camera raw'. Play with your file in Camera Raw to your heart's content. > A Raw file is simply the sensor output without any software interpretation > (other than the obvious firmware interpreting the RGB value to give photon > strengths received). That is true. The difference between camera chips and scanner chips is that cameras use Bayer filters over the sensor. I'm sure we all have some concept of what that is, so I won't get into it. So the raw data of the sensor is a mosaic of RGB values. But it's not full color yet. Cooking the raw file interprets the raw data and demosaics it, giving us our RGB output file. It's during this process that you can set the white balance, since you demosaic the data differently depending on the chosen balance. Most scanners do not use Bayer filters. They read R, G, and B values for every single pixel. There is no interpreting of the data to get an image like there is for a raw file. So while you can store it in a DNG, the data isn't raw. It's the same as would be stored in a tiff - RGB for every pixel. You can call it raw if you want, but it's already 'cooked'. You can store it how you want, but you gain no advantage.