Photoshop B&W RAW help!

[480sparky]

Is it a smaller file size? (stupid question but concerned)

Raw files are naturally larger because they contain much more data...... data that any in-camera conversion deletes after the conversion.

In a nutshell, raw files are a recording of all the data that came off the camera's sensor, with minimal processing needed to make it a format the camera can record.

JPEGs are smaller because you tell the camera to 'process' that raw data into a standard-format image, and in the process the software deletes 70 - 85% of that data.

 

[KmH]

The image sensor in a digital camera is color blind, and incapable of recording colors.

The only information a pixel records is an analog voltage whose amplitude is a function of how many photons (particles of light) hit it during an exposure. The more photons that hit a pixel during the exposure the greater the voltage the pixel develops.

Each pixels voltage has to be amplified. That amplified analog voltage then has to be converted to a digital number. DSLR cameras make it a 12-bit or 14-bit number.
A 12-bit digital number can only code 4096 discrete levels. A 14-bit digital number can only code 16384 discrete levels.
Those 12-bit or 14-bit numbers are what a Raw image data file contains. In other words the Raw file only contains grayscale luminosity information, and camera metadata.

Raw converter applications manipulate the Raw image data in a number of ways to make it something like what the human eye sees through the camera viewfinder. If you use Live View on the rear LCD when you are shooting RAW, you are being shown JPEG images, not the Raw.
NOTE: JPEG is limited to 8-bit digital numbers, which can only code 256 discrete levels.

http://www.adobe.com/digitalimag/pdfs/linear_gamma.pdf
http://en.wikipedia.org/wiki/Raw_image_format