Difficulty with Apperture/Shutter speed

[nostromo]

Hi, New to forum and absolute photography novice.
I have read tutorials ralating to appeture and shutter speeds and set my camera up on a tripod in my lounge to take shots from a contant position and light source to try and practice.
I am using a Fuji S6500 camera. When in manual mode the camera displays a sliding bar with a plus at one end and a minus at the other to try and help you guage apperture and shutter speed. The idea being that you get the pointer in the middle for both.
When I take a shot in Auto the camera takes the shot quickly with a crisp focused outcome but when I try it on manual using the slider to help guage my settings the camera takes 3-4 seconds to take the shot which then comes out very grainy.
I have tried to ignore the slider and set the apperture and shutter speed myself starting with extremes of each in various combinations to try and get to grips with how each affect the shot but just cant seem to get a good shot no-matter how I refine the settings and cant figure out how the camera is doing it in auto.
Is there any rule of thumb I could use as a starting point when setting up a shot or am I completely missing the point. I realy want to get to grips with this and understood what I read in the tutorials but just cant seem to put it into practice.
Mark

[Jim Poor]

Sounds like you are missing the point.

The scale with +/- that you see is your exposure meter. + is over exposure and - is under with the center being what the camera "thinks" is correct.

Which metering mode are you using? If you are spot metering, the exposure can be correct for the small area being metered, but totally wrong for the rest of the image. Conversely, if you are using matrix metering (or whatever Fuji calls it) the exposure can be OK for the overall frame but way off for the small portion of it that happens to be the subject.

Look at your exif data to see what settings the camera chooses in auto and then switch to manual mode and adjust (one setting - either aperture or shutter, for now) up and down to see what happens. Then go back to the settings the camera picked and adjust the other setting up and down.

[Swisstony10]

It also sounds like although the camera is letting you pick your own shutter speed and aperture, it's choosing its own ISO setting to account for what you've picked, which would explain why images are grainy when you shoot indoors (when you use the full auto mode, it's quite likely picking the most suitable combination of all three, with the lowest ISO it can get away with).

If you have a scout through this site for a thread explaining the much-referred-to Exposure Triangle, that'll help you to understand the relationship between shutter speed, aperture, and ISO, which in turn will help you fully understand what it is you're doing with your experimentation.

Experimentation is a Good Thing, but it's most helpful when you have an overall understanding of what it is that you're experimenting with. You're off to a pretty good start though, by actually wanting to understand it, and I reckon you've come to the right place to ask for help.

Russ.

[Marija]

Could you, or someone please explain a bit more about this.....and what does the red spots shown by camera in +..........- mean?

Originally Posted by Jim Poor

Look at your exif data to see what settings the camera chooses in auto and then switch to manual mode and adjust (one setting - either aperture or shutter, for now) up and down to see what happens. Then go back to the settings the camera picked and adjust the other setting up and down.

Thanks!

[Swisstony10]

Exif data is a whole bunch of bits of information which your camera attaches to each image, telling you all about the different settings that you or the camera used to take it. If you look at any of the pictures on your Flickr stream (some great shots in there, by the way) you'll see a link on the right hand side that you can click on which says "...more information.." - that'll display the Exif data for that image. Amongst other things, it'll tell you what focal length you were zoomed to, what aperture setting, shutter speed, and ISO you used, as well as whether you used a flash or not.

Here's the most comprehensive description I've seen so far of Exif data (thanks Wikipedia!) Exchangeable image file format - Wikipedia, the free encyclopedia

As for the "+...........-" thing - that's the exposure meter on your camera. It's basically measuring the amount of light coming into the lens from a given point or range of points, depending on what kind of metering your camera is using (or can use) - there are a number of metering modes, so it's probably best to read your camera manual to see what kind of metering options it has. If you're shooting in a manual or semi-manual mode, that'll tell you whether, for your current settings, the shot would be over or underexposed, or just right. Generally, you want whatever marker your camera uses to be in the middle of that. Going towards the "-" will mean you're underexposing (which is great if you deliberately want to underexpose), while going towards the "+" will mean you're overexposing (again, great if you want to deliberately overexpose).

Does that help?

Russ.

[Jim Poor]

Good explanation of exif, except:

Originally Posted by Swisstony10

. . .you'll see a link on the right hand side that you can click on which says "...more information.." - that'll display the Exif data for that image. . .

Only if the image was saved in such a way as to preserve the exif information. Save for web in Photoshop CS3 and earlier strips the exif data in favor of smaller file size. CS4 has some options to retain exif while using the save for web feature.

[Swisstony10]

Thanks for the extra info Jim - although before I added the bit about "more info" on Flickr, I checked the poster's Flickr stream to make sure they had some info attached. I know that depending on how I've processed my images, a lot of my stuff ends up with no Exif for Flickr to show...

Russ.

[Jim Poor]

Cool. I tried to get at the exif with my exif reader plug-in and it came up empty on this shot so I just [eek] assumed it wasn't going to be on any.

[Samanax]

Originally Posted by nostromo

Is there any rule of thumb I could use as a starting point when setting up a shot or am I completely missing the point. I realy want to get to grips with this and understood what I read in the tutorials but just cant seem to put it into practice.

Exposure Triangle

The Exposure Triangle – In Beginner Speak “The End of Auto Mode"

Understand Digital Photography exposure – The Exposure Triangle

Understanding Exposure with the Exposure Triangle

Making Better Images With The Photographic Triangle

Lens Aperture Explained – Exposure Triangle Pt.1

Shutter Speed – Exposure Triangle Pt.2

ISO – Exposure Triangle Pt.3

[Swisstony10]

Hahaha! I similarly checked a single picture and assumed that they all had it!

What is it that they say about assming again? "Never assume - it makes an ass out of u and me..."