monitor calibration

I purchased monitor calibration software (colourvision Spyder2). It made a huge difference in color but there is only one thing.....when i open photos in photo shop and lets say i convert photos to blk and wht, i can greys to not mix smoothly......its like i can see were the tones change from light gray to dark gray to blk....i do not know if that makes sense to anyone but is that because my monitor cannot handle the color or something or maybe the video card?.

What you are describing sounds like posterization, which is a term that describes the lack of smooth change in tone over an area. It jumps in clearly defined steps from one tone to the next so that it looks like each region was painted from a different bottle of paint.

That should not happen as a result of calibrating a monitor. That would happen if the image has been manipulated in such a way that the areas of low detail have been artificially expanded (as in greater contrast), and it can also happen as a result of too much JPG compression.

right and wrong. It will not happen from callibrating the monitor, but can definatly happen if the spyder made a bad profile of the monitor.

In my mind, making a good/bad profile and calibrating the monitor are one and the same thing - it's just a question of whether or not it works - so, in that sense the calibration can cause the problem. The mystery would be, why does it only affect his B&W work, and not his color work?

quite possibly because the tonality of B&W is so important to the image that this is the first time its noticed.

When working at the lab, we would make custom profiles for a machine, and anything with gradients is where the profiles would fail if they were incorrect.

I suggest doing a perfict black and white gradient strip in photoshop (lets say 2in x 24) and then run the posterize filter over it with 25 steps, giving you a 25step greyscale. If you see that two or more of these steps are the same tone, theres something funny with your monitor. If you see it in the gradient before the posterize feature, thtats a more clear sign there's something wrong.

but, usually this shoes up in B&W because if the tonality importance over color, and in sunsets with bright gradients.