D40x sharp spots on long exposure pics - Nikon D40x Digital Camera

Hi jchp_2001, I want to help you with your question, but without more information from you, I can only guess what you mean?
What do you mean by "sharp spots"? I will assume that you are talking about speckles of white or colors in the deep shadow areas of your pictures or in black areas of night time exposures. What you are seeing is electrical noise generated by your camera's sensor and amplified by other electronic circuitry in your camera. Newer and more advanced cameras have higher signal-to-noise (S/N) ratio circuitry that reduces, but does not entirely eliminate the problem. The S/N ratio is a measure of how much stronger the picture information is than the electrical noise (analogous to to the static you hear on a week AM radio station). The higher this ratio, the fewer artaffects, such as spots, will appear in your pictures. There are a couple of ways to lessen this problem. You could use a shorter exposure time, lower the ISO setting on your camera (of course that would increase the required exposure time and my nullify the benefit), or illuminate the shadow areas with supplemental lighting. The other way is to buy a newer camera that has a higher S/N ratio. One of the main goals in new sensor and camera design is to raise the S/N ratio. Trading in your D40x on a newer model DX (24x16mm sensor) format camera will help. The reason that professionals more advanced photographers spend thousands of dollars on full frame (36x24mm sensor [the same size as a 35mm film slide]) digital cameras such as the D600, D610, D800 or D810 is because the larger sensors have an inherently higher signal to noise ratio. That is in part why your D40x gives you better quality pictures than a Coolpix camera for example, which has a smaller sensor.