If it is your first DSLR, then no.If you have a lens kit already there is no need for that. If the price between a body, and body + kit lens is negligible, then it’s ok to get one with the lens, if you’re just starting out and have no other lenses.Some kit lenses are paired quite well with their camera bodies, and do perform decently.Experiment with the kit lens, discover shortcomings, if any, and use it to help decide what to purchase next as you learn and progress.

Types of equipment that are needed to shoot long exposures

A tripod – this is a good piece of equipment to have in most instance, but is a critical piece of equipment for shooting long exposures. Make sure your camera is properly mounted on the tripod before you start shooting.

A camera – obviously you will need a camera, but many people assume you can only do this type of photography with an SLR. Some advanced point-and-shoot cameras can also do long exposures if they have a Shutter Priority function. Take a look in your camera’s manual to see if it has this function, you may be surprised.

Cable release – your camera will be on a tripod, so it should be very still, however, sometimes the action of pressing the shutter release button can cause the camera to move slightly and this movement can cause your image to blur very slightly. You may not notice this on the LCD screen, but when you open the image on your computer, it will be evident. I recommend getting a cable release (also called a remote trigger). It is simply a cable that attaches to your camera and acts as a shutter release button. Using a cable release means you can set up your camera, step away from the tripod and press the button without touching the camera. Cable releases can be wireless too. If you don’t have a cable release or don’t want to buy one, you could use your camera’s self-timer function to trigger the shutter.

Camera settings should be used

Shutter speed – depending on the light in your scene, your shutter time will need to be at least 10 to 15 seconds, or longer if necessary. If you are doing a seascape and the water is moving quickly, then a few seconds may be long enough to make the water look misty.

Aperture – you will want to have your aperture set at anywhere between f/8 and f/16. This again will be determined by how much light is in the scene and how long you want to expose for.

ISO – keep your ISO settings as low as possible, ISO 100 is what I use for long exposures.

It’s normally a good idea to shoot long exposures as the sun is setting, or just after sunset. My suggestion is to be on the scene an hour before sunset. That way you can test some shots, make sure your composition is good and be sure all your settings are correct. 

You can use any lens for Bokeh Photography, Bokeh is defined as “the effect of a soft out-of-focus background that you get when shooting a subject, using a fast lens, at the widest aperture, such as f/2.8 or wider.” Simply put, bokeh is the pleasing or aesthetic quality of out-of-focus blur in a photograph.

Its the Aperture that is denoted by f and it is also known as f stop.

The diffrence between both  is that f/1.4 lets you get more light to your image.

rather f/1.8 lets you get less light in your image.

More the aperture less the light and less the aperture more the light .

and one of the main use of it is the depth of the field.

Suppose you want your background to be blurred at a good rate then use as low apeature as you can.

Hope you will find it helpful.

1. Shooting with 50mm lens can let you shoot at aperture as wide as 1.8 but a 18-55mm will allow you to shoot only at 5.0 aperture 
2. This difference itself is a huge deal. This means you can have the advantage of having faster shutter . Imagine shooting handheld at 1/15s with aperture f5.0 and then at 1/125s with aperture f1.8. This can be significant in low light conditions.

First of all that you should not try to disturb the audience. Always try to capture pictures from roaming around the walls of auditorium. Better to go with Telephoto for taking candid shots for stage subjects or from the audience.

Another thing is that you can use another camera for wide angle shots of entire stage or the audience.