Help with shutter/aperture speed

[OpticalPrime]

Okay guys, please excuse my ignorance. But I am BRAND NEW to the hobby. In fact, Id go so far to say I know nothing about it. Iv had numerous cameras over the years but never really did anything but snapshots on AUTO settings.

Recently I got what I would consider a good camera. Its a Canon S2 IS. I know its not a professional and probably not "good" on most of your terms. For the past 6 months or so I have taken lots of pictures with it, but again all in AUTO mode...

Just recently I have decided to venture into a new hobby of taking pictures. Iv been very pleased with some of my recent pictures so much Id like to take more and more... (mostly of family)

So today I joined this site and did a little reading, but one can only read and search on their own long enough before I had to go and ask some questions. My camera has alot (so i think) of settings to it. I can adjust shutter speed, aperture, iso, etc... Until today I had no idea what any of those were.

I did a little reading and I think I have the basic understanding, but still not sure when/why I would change these things. Was hoping for a little insight. But here is my interpretation.

1. Shutterspeed - the time the shutter is open. A quick shutterspeed will take a fast picture. A slow shutterspeed will take longer to take the picture. So if taking a picture of a person throwing a ball. Quick shutterspeed would get an instant picture with no blur, whereas slow would take longer and make a blur effect....

I get that, could be cool for many different numerous reasons. Sports, lights on moving objects, etc... But what other reasons would you adjust the shutterspeed???




2. Aperture - From my understanding this is the size of the hole in which the camera sees light. The smaller the hole, the less light it sees. The larger, the more... So in the daylight outside, you would typically want it very small?? But at night in dark, you would want it larger?? Other than lighting reasons like that, are there other benefits to changing the aperture??



what about other stuff like ISO speed? what is that? What about other functions of my camera. I would REALLY REALLY LOVE if someone could give me a beginner break down on some of this stuff without having to spend hours and hours digging for the answers..

thank you ahead of time.

[LoungeLizard]

Aha...first off, get the book "Understanding Exposure". Great one.

You've got shutter speed right. f/stop (aperture) is correct - except that it also controls the "depth of field". That is the amount of space in front of and in back of the subject that is in focus. The smaller the f/stop (larger number), the more depth of field. The larger (smaller number), less depth of field. That is what gives you that beautiful blurry background in portraits or blurred crowds in a sports photo. So while you have the part about allowing light in correct, f/stop is used for creative purposes also.

ISO is the sensitivity to light - comes from the old ASA (ISO) speeds of film. The higher the number, the more sensitive to light. This comes in handy when shooting in very dark environments. A shutter speed of 1/60, an aperture of f/2.8 at ISO 200 is TWICE as sensitive to light as at ISO 100.

All of these interact to get you the exposure you want. The can also be used for creative purposes (I mentioned the use of aperture before.)

Do some basic research on Google - or just get that book - and it'll go into it all in much more detail.

[OpticalPrime]

thank you, that explains even more. I guess I just need to read read and read some more along with just playing with the camera. But anymore advice is greatly appreciated.


I do have one more question a little bit off topic. I own a small trophy/award store and Im currently building my own website. It is coming along very nicely. But there are a handful of items I sell where I am going to have to take my own pictures because my supplier doesnt have any premade professional ones for me to download.

These items are all crystal and Id like to make the picture look like this... dark black background with the piece lighted up... any idea on how I would do it? I built a small black box and have a very small light im using as a spotlight where I shine down on it, but they never turn out this nice in my "auto mode"

[OpticalPrime]

i was looking and my camera's settings and here are the ranges in which I can use.

aperture is F2.7 - F8.0
Shutterspeed is 1/3200 - 15 sec
ISO - 50,100,200,400

are these good settings to work with?

[Wes]

00bolt:
The "Understanding Exposure" book does indeed rock. Here's something else that might help. I run a Christian bulletin board and answered a question very similar to yours. Here is the link: http://p076.ezboard.com/fchristianco...opicID=1.topic

Hopefully that will help.

[brad]

You've already replied to my basic camera class thread... that's also a good place to start. You really have to see it to understand it... the book recommended here is GREAT for that, as well.

[johnastovall]

Two classic textbooks.

Photography (8th Edition) (Paperback)
by Barbara London, John Upton

Basic Photography, Seventh Edition (Paperback)
by Michael Langford

You should be able to get them from your local library.

[DEMDeepEllumMusic]

With most digital cameras the lower the ISO # the less electronic noise will show up in the picture.

I would bet that the aperture goes closer to an f-22 and not just f-8.0 as you stated-F22 is just at the edge of good landscape shooting, the large format guys go into f-64, f-128 and even a few are at f-256 (which is a very very very small lens opening but allows very very very deep areas of view in focus).

Another thing to realize is if you have a built in flash the camera probably has an exposure time of 1/60th of a second and uses the short flash duration time to help freeze subject motion.

Those pictures that you may have seen showing a bullet striking an apple or of an exloding baloon are actually taken using very strong but very short time period flashes and not extremely fast shutters. They go into a pitch black room and fire off a strobe at 100,000th of a second or faster to get those magic looking shots while your strobe on your camera may fire off at 1,000th of a second or so.

But think of it this way-old school you bought a speed of film to put into your camera and then you set the camera so that you knew what speed of film was loaded-film used to be 25, 50, 64, 100, 200, 400 speeds and lately they added 1000 and 1600 speeds. Well now you just set the sensitivity of the sensor to 50 to 400 (on your camera).

Next you go to a scene and see how much light is really there (how much the particular lens on your camera can let in when it is wide open) and then you go from that limit from where the lens is open to it's max which will give you the shortest exposure time. Think of it that you have to have so much water through a hole and with the biggest hole (f-2.8) it will take the least amount of time to let through X amount of water. As you make the hole smaller (f-4.0) it will take a bit longer to let X amount of water get through and if you make the hole very small (f-22) then it will take even more time for it to pass through.

I would do a search here on ASA, F stop, exposure times, brokah, depth of field, etc.

[KJ Smith]

Howdy 00, Welcome to the site.

I second the first book John recommended. That is the book used in most classrooms, and it is not a terrible read.

On your lighting ? Try to find a piece of white cardboard, lay you Crystal down on it, trace it out. cut the card board apx 1/8th inch smaller than actual size, leave a tab a little smaller than the base on the bottom. Bend the bottom base part 90*, and stand your object on the base part, with the traced part standing up behind the crystal. if this is done right you will not see the cardboard, but your crystal will appear white. You may lose some detailin the crystal though. You can use sliver board also. Shooting Beer we used gold.

Did this make sense ?

Give a try, no guarantees

Kevin

[LadyShutterBug]

aperture = how big of a hole the light has to come through.
low numbers = bigger hole.
high numbers = smaller hole.
think of your eyes in a dark room. your pupils are large-- because the hole in which your eye lets light through is open wide to let in lots of light. when you're outside on a sunny day, your pupils are tiny, because your eye only wants to let in a little light.


shutter speed = how long that hole stays open
think of your eye, and how long you need to keep your eyes open to "see" in a dark room. if you open and shut them quickly, you don't get enough info to know what is around you... but leave them open a while and you gather enough information to "see".

think of your eye on a bright day outside... you can open your eyes and shut them quickly, and still you gathered the info of what's around you.

ISO = light sensitivity
When you use film in cameras, you have to choose a "film speed", or sensitivity, so that the film was sensitive enough to record the light information for whatever you were shooting. Digital cameras allow you to set an ISO.
Smaller numbers = less "noise", or grainy-ness, distortion in your image. ISO 100 is almost always going to be nice and clear and sharp, all other things being equal. It's the speed you would choose, say, if you're shooting outside on a very bright sunny day.

ISO 1600 is going to be grainy. Not like pixelated, like film grain. If you are shooting in dark places and need to make your ISO high, your images won't be as sharp, but there are programs that can help reduce the noise and make the images look very nice.

All three of these things work independent of one another, and you have to find the right mix of the three to capture the type of image you're trying to get under your light conditions. If your lens doesn't stop down to 2.8 and you're shooting in the dark, you've got to bump your ISO up, and/or go for a longer shutter speed.

*****************

I like to think of an image as a bunch of light gathered by worker bees.

Aperture = how large of a hole the bees have to fly out.
Shutter speed = how long they have to get out of the hole and come back in
ISO= number of bees.

The bees' job is to go out there and bring back some light information for you!

There may be a lot of light, or it may be kinda dark.

You have to decide how many bees you're gonna send out, or if you only want to send out a few bees, then you have to decide how long to give them, and how large of a hole to allow them.

Big hole? Lots of bees? then you don't need to leave the hole open very long-- but be careful! Sending out a lot of bees can mean that they don't all do a great job, and that means you get noise in your image.

[Stephen H]

I just got a new digital camera, and it goes to f/8 only, manually. The manual says it can go to f/11 or f/16 under auto control, and depending on the other settings.

Some of the settings make a lot more difference on film or high-end cameras. For example, my lowly K1000 can shoot everything from ISO 25 to ISO 10,000, with lenses that go from f/1.4 to f/32 or so (not all on the same lens). And it makes a lot more difference, then, how things are set.

The actual settings you use are usually a compromise of some sort. You get more depth of field with smaller aperture, and you can intentionally decrease depth of field with larger aperture, but most lenses don't offer optimal sharpness at either aperture. So unless you're intentionally trying to adjust depth of field, you'll be shooting at some "middle" aperture.

You can freeze motion with fast shutter and blur it with slow shutter. For most purposes, if you have good light, you can set the aperture and adjust shutter to whatever you need for exposure.

[Daniel M]

I can officially recommend the book "Understanding Exposure" revised edition by Bryan Peterson, copyright 2004. I received it as a Christmas present and it has been invaluable as a learning aid. I am totally new to the DSLR scene and have no experience with anything but the small point and shoot cameras. I gained much knowledge and understanding from the book . The book is not long winded and easy to read.

Get it, you won't regret it.

[Lucifer]

Toy around with it. When I got my camera, I toy w/ it a lot.. .. I don't even remember the theory of shutter spd, ISO, or anything. But at least I know how it affects the image. You will learn many stuff by experiencing it before you even know it. Just click . .click. . and have fun.

[engstrom]

One other thing to keep in mind - the smaller the size of the sensor the larger the depth of field (distance in front of and behind the subject that will be in focus). Since your S2 IS has a pretty small sensor you won't be able to get images that just have the subject in focus and everything in front of/behind it be out of focus (OOF). Still, by increasing the aperture to 2.8 (or 2.7 in your case) manually you should be able to reduce the depth of field. Also, the closer you are to your subject and the larger the focal length (zoomed as far as you can) the smaller the depth of field.

[KJ Smith]

Originally Posted by engstrom

the smaller the size of the sensor the larger the depth of field

Howdy John,

I have never heard this before. Do you know the theory behind that, or provide a link where I could read more about it ?

Thanks
Kevin