Don't be bashful! If you want comments, give comments. You don't need to be an expert photographer to express your opinion about the work of others. You don't need to go into great depth. A simple remark about cropping, composition, color, subject matter, etc. can be of just as much help to a budding photographer as an in-depth critique.
Twilight, nighttime and low light offer some of the best opportunities to shoot dramatic images. Whether you’re shooting outdoors in the evening or indoors in a low-light situation, chances are that you’ll make long exposures. This requires use of a tripod and a cable release to avoid shaking the camera when it’s set for several seconds or on a bulb (B) setting. You also want to carefully meter your exposures, as there may be sources of light that appear in the frame that can fool your camera’s meter. Bracket your exposures and shoot lots of images.