Compare Brightness Between Lasers

We know the power output of a laser is difficult to visualize. That is, how bright exactly is a 55mW green laser compared to a 125mW green laser ? Since the 125mW green laser is twice the power, does it mean you will get double the brightness? This section, hopefully, will help answer some of these questions.

The pictures below are computer generated images. We tried our best to take real life pictures comparing each laser model. However, this was extremely difficult when various shutter speeds, exposure settings and angles of laser beams resulted in inconsistent pictures. After an entire night out and taking more than 200 pictures that went into our computer's trash bin, we decided to create computer generated images to the best of our knowledge and abilities. We are laser experts, not professional camera men!

The ordinary 5mW green laser emits only a faint laser beam in dark conditions. Sometimes when there is excessive ambient light, the laser beam will become very dim and difficult to find. Therefore, If you plan on buying a high power laser for astronomy, buy a 15mW or above laser .

In the above picture, while the 125mW green laser has nearly double the power, it is NOT double in brightness. Brightness and power output do not increase in proportion.

The green portable lasers have larger beam diameters therefore you will see a much wider, thicker laser beam.

We bet you are surprised with the picture above. Why is the 50mW red laser, with 10 times the power of a 5mW green laser so dim? The reason is because the human eye is very sensitive to the color green. Even though the 50mW red laser is more powerful, it offers brightness comparable to a 5mW green laser pointer.