Exposure compensation and Shutter speed

[cauger61]

I understand that in a low light situation without a flash, the following combination best works:

• high ISO (say 800)
• large aperture
• slow shutter speed

However my camera (Canon sx510 hs) is not a dSLR one and it does not support f-stop below 3.4.

My question is: suppose that if I go by aperture priority (Av) mode, can I achieve slow shutter speed by lowering the Exposure compensation, apart from the other settings mentioned above. Of course I shall be using a tripod in that case.

[Inkanyezi]

When you use the Av mode, the camera sets exposure with the built-in meter. You need not use compensation unless you want to make the image brighter or darker. In Av mode, setting a minus value for compensation will cause the shutter speed to be faster than when in zero. By compensating with plus, the shutter speed will be slower.

Compensation is there to tell the exposure system what kind of scene you are supposed to take. If the scene is darker than "normal", minus compensation makes the image dark. If it is brighter than "normal", setting plus compensation makes the image brighter.

So say you take skiers on a mountain side. Snow is very bright, so a plus compensation of 1.3 might be necessary to get white snow, rather than dull grey.

If you take a photo of a black cat against a dark background, compensate toward minus in order to make it black, otherwise it will be much brighter than you'd wish.

When photographing a medium brightness image when there is little light, apply no compensation. The camera will increase exposure time as needed automatically.

[Mike Buckley]

You're planning on using a tripod. So, configure the ISO to the camera's base ISO value and configure the aperture to achieve the desired depth of field. In other words, the tripod eliminates all need to make any compromises with regard to those two settings.

You mentioned that you are planning on using a slow shutter speed, so all of the above is mentioned with the idea that you have no need to stop any motion in the scene. That being the case, you shouldn't care how slow the shutter speed becomes as a result of your ISO and aperture settings.

[Shadowman]

In a lowlight situation you first (after deciding on composition) need to acquire an area of focus, it might be a light source or a illuminated region. You might even need to use a torch just to get the camera in focus. Once you've acquired focus you can then follow Mike's advice on selecting the camera's setting, and if you've set ISO to lowest setting allowable, are using a tripod, and don't have to worry about moving objects then as Mike said the two remaining settings of aperture and shutter speed are your only concern.

[HaseebM]

Do you plan on taking pictures of landscape or the sky?