I've noticed that there are several very good photographers on this forum and wondered if any of them had any free time to pass some knowledge on to me?

I'm off travelling next month and would really like to capture some really nice photos to remember the journey.

I have read a fair bit on the subject and understand several of the 'rules of composition' but am struggling with shutter speeds, Light Sensisitivity and apeture. I do not have an SLR camera but have a relatively decent Canon; the powershot A640.

If anyone could give me a few tips or some advice of when to use specific setting I would be very grateful.

Pick up the book "understanding exposure" it covers those elements quite well.

Advising on when to use a specific setting is a tricky thing to do because it will depend on the scene, situation, lighting, and the intended effect.

Here's a (very) rough guide though -

Light sensitivity (by which I assume you mean ISO) - switching between ISOs on your camera gives you an extra stop of light (eg from 100 to 200), which means that your shutter speed can be faster, or your aperture smaller, for the same exposure. This might help to hand-hold in poor light, for example. However, your photos will be noisier as a result.

Shutter speed - fast (short) shutter speeds freeze movement, slow (long) shutter speeds blur subjects, and convey movement. Use each according to your intended result.

Aperture - Larger apertures (smaller f\ numbers) give shallower depth of field (less in focus at once) and allow more light in, so your shutter speed can be faster for the same exposure. A compact may not allow you the same freedom with regards to shallow depth of field as an SLR as their design tends to result in back-to-front sharpness.

Have a look at http://www.guide-to-photography.com/ for some photography tips and advice.

To be honest I've learnt all mine through trial and error over two years....

take a shot of the same thing on as many different setting as you can do... remember which was which (vital) and work out what you like and don't like from there. It really is worth it and you get to know your own camera and its limits better... don't be scared of taking hundreds of pics :)

One specific problem I was having while taking a picture yesterday was that I could't get the sky to appear blue, it kept shooting as bright white.

I changed the ISO setting to 80 to try to avoid it, narrowed the apeture to and shortened the shutter speed to 120th second but it still appeared overexposed and the histogram agreed with me. Any ideas on this one?

Further question... When should I use a shutter speed of 10 seconds for example? I wanted to do it during daylight but the entire image came out as just white

I have taken the following pics if your interested: http://homepages.shu.ac.uk/~mledger3/photos.html

One specific problem I was having while taking a picture yesterday was that I could't get the sky to appear blue, it kept shooting as bright white.

I changed the ISO setting to 80 to try to avoid it, narrowed the apeture to and shortened the shutter speed to 120th second but it still appeared overexposed and the histogram agreed with me. Any ideas on this one?

Cameras usually have a exposure lock which can be used for this. The idea is that you point the camera at something darker (or lighter depending what your doing) than the thing you want to take a picture of (in your case the ground), activate the exposure lock then point at the thing you want a picture of (view with the sky) and take the picture. It's usually activated by pressing and holding the shutter release button half way down and then press it all the way to take the picture. Check with the manual for details for your camera.

Further question... When should I use a shutter speed of 10 seconds for example? I wanted to do it during daylight but the entire image came out as just white
It needs to be dark for you to get anything with that long a shutter speed. Things like light trails of car headlights at night are good. You need to hold the camera very steady though - tripod, put it on a wall, etc.

Misty waterfalls can be good too but you'll probably only need a few secs for this.

One specific problem I was having while taking a picture yesterday was that I could't get the sky to appear blue, it kept shooting as bright white.



If you were trying to shoot a bright sky with a dark foreground, then you may end up with this situation. On an SLR you could use a graduated filter to even the two out. With a compact you may have to accept some degree of blowing out of the sky if you want to record good ground detail, or you could see if there is an alternate metering mode that may produce a better effect. Either that or take two of the same shot and merge them in post-production.