OK, the Sony Alpha is a good camera...so you are doing OK there. I think it's a little behind Canon, in terms of noise, but you should certainly be able to get very clear images at the lowest ISO settings. As I mentioned, you should always try to use the lowest setting. It may be hard to get a good shutter speed with continuous lights though. Your settings should be embedded into the images. Photoshop or your camera's image software should have an option to show you all of the shooting information. It might be a good lesson for you to review this info for the shots you like and the ones you don't. As for processing that will bring out noise...typically, the more you try to change the brightness/tone/contrast of the image, the more the noise will be evident. Again, getting the exposure right will help. Do you need a light meter? It would help, especially if you ever decide to use flash/strobe lights. (You would need a flash meter). However, you have a digital camera, so you it to your advantage. Don't use the image on the camera's screen though. Set your camera to display a histogram of the image. Take your shot, then review the histogram to see if your exposure is OK. HERE is a good link for learning about the histogram. There are other methods to getting your exposure set properly. You could use a grey card, for example.