Some Serious "dumb" Questions.

[cyracles]

I use a canon 1000d(am a newbie) and i still have problems getting it right. When i choose an aperture setting on my camera, sometimes the shutter speed blinks which some book interpretes as the camera not being able to select an appropriate shutter speed to complement the fstop number. If i still patiently scroll through other fstop values, the shutter speed still keeps blinking(not even minding that, i no longer have the aperture setting i want.).

If I proceed to take the shot anyway, guess what.....it comes out not so good or blurry as a result of camera shake.


I usually use manual focus because my autofocus does not really get the focus when i want it to....the problem i have however is from tutorials i see about how to focus. I once heard a tip from a landscape photography text that one should focus the third lower part of your image. Now, the technique is not my problem because i'm not even good enough to know its merits. My problem is that what does it mean "to focus on a part".

Presently, focus for me means adjusting my focus ring till the image is as clear as it can be. How do i focus on a part exactly.

I need help!

I await your response.

[Izzy]

Check what ISO it is set for. Make sure it is set to auto. This sounds like it might be set for 100.

Also you can change what focus points you use. I use only the center one on both my cameras and the pictures are coming out so much better for it.

[i speak in math]

Originally Posted by cyracles

I use a canon 1000d(am a newbie) and i still have problems getting it right. When i choose an aperture setting on my camera, sometimes the shutter speed blinks which some book interpretes as the camera not being able to select an appropriate shutter speed to complement the fstop number. If i still patiently scroll through other fstop values, the shutter speed still keeps blinking(not even minding that, i no longer have the aperture setting i want.).

If I proceed to take the shot anyway, guess what.....it comes out not so good or blurry as a result of camera shake.

You may be setting the aperture so small that it is essentially a pinhole and you would need a long long time to get an image to "burn" into the sensor. The shutter is flashing because it cannot be open long enough to get a proper exposure. You can open the aperture more (say, f/5.6) which is usually where a lens it sharp enough but still lets in a fair amount of light. Or you can raise the ISO to make the sensor more sensitive to the light. You will be able to raise the shutter speed high enough to not have blurry images. Of course, this all depends on the available light you are shooting in.

Originally Posted by cyracles

I usually use manual focus because my autofocus does not really get the focus when i want it to....the problem i have however is from tutorials i see about how to focus. I once heard a tip from a landscape photography text that one should focus the third lower part of your image. Now, the technique is not my problem because i'm not even good enough to know its merits. My problem is that what does it mean "to focus on a part".

Presently, focus for me means adjusting my focus ring till the image is as clear as it can be. How do i focus on a part exactly.

I need help!

I await your response.

The reason for the 1/3 bit is because of this: When you focus on something, the aperture (among other things) setting gives you certain distance of depth of field. Anything in that depth of field is in focus. It can be very narrow or deep. But the lens and camera are calibrated so that 1/3 of your depth of field is in front and 2/3 of your depth of field is behind the focus point.

Thus for landscapes where you want everything in focus, you set a small aperture like f/11 or f/16 and on a wide angle lens, your depth of field is huge. If you focus at infinity, then objects right near the camera will appear out of focus because the "in focus zone" is set so far away. But if you focus 1/3 the way into the scene, then everything from the camera to the horizon should be in focus.

[gptwins]

There are some good responses here so I will recommend a good book for you, "Understanding Exposure".

Photography is essentially about getting light to you film/sensor. There are three basic ways you may accomplish that: time (shutter speed), opening (aperture), and sensitivity (ISO for film speed).

Time is pretty self explanatory. How long is the shutter open.
ISO determines the sensor or film's sensitivity to light.
That leaves opening or your aperture, or f-stop. In very simplistic terms, this is the fraction of your lens opening. f1.4 is 1:1.4 or 1/1.4. f4 is 1:4 or 1/4 of the opening.

So the larger the f-stop number the smaller the hole allowing light to the sensor.

[Krusty79]

Following up on what ISIM said, you should check out this url:

Online Depth of Field Calculator

[NgaiHill]

Your post raises questions like, what is the available light? Are you trying to shoot in low light? What are you trying to shoot? Flowers, people, landscapes?
I have the 1000D as well and it is a great wee camera. If you are having trouble getting the right settings for the correct exposure my suggestion would be to try taking the photo on auto. Have a look at the shot and see what settings the camera used. Look at the three values - Speed, Aperture & ISO. Work out why the camera used those settings, and decide what you want to change to get your desired effect.

[inkista]

Originally Posted by cyracles

I use a canon 1000d(am a newbie) and i still have problems getting it right. When i choose an aperture setting on my camera, sometimes the shutter speed blinks which some book interpretes as the camera not being able to select an appropriate shutter speed to complement the fstop number.

Yup, that's what the blinking setting means.

If i still patiently scroll through other fstop values, the shutter speed still keeps blinking(not even minding that, i no longer have the aperture setting i want.).

Two things to keep in mind: 1) lower f-number = bigger aperture (more light, faster shutter speed). Higher f-number = smaller aperture (less light, slower shutter speed).

2) How wide you can open up that aperture is determined by your lens, not your camera. Every lens is described by its focal length and its maximum aperture. If you're using the 18-55 kit lens, zoomed all the way in at 55mm, then your max. aperture is f/5.6. And that's pretty small. If you're shooting indoors without a flash, f/5.6 is unlikely to work for you at any shutter speeds where you can handhold.

I usually use manual focus because my autofocus does not really get the focus when i want it to....

You probably don't have enough light. The camera uses contrast detection to autofocus. You need to aim at something well-light or throw light on the subject (say with a flash light), and choose a high-contrast target (ideally where black meets white with a sharp edge) to help out the camera. Again, the max. aperture of the lens will also affect how much light is getting in for the camera to see by.

A camera is nowhere near as sensitive as your eyes in low light. What may seem like "enough" light to you, may still be far from enough light for a camera.

... I once heard a tip from a landscape photography text that one should focus the third lower part of your image.

Um... Not really. The rule of thumb is focusing 1/3 of the way into the scene. But this assumes that what you want in focus is everything, and that you're going to want infinity (or the horizon) in focus as well, and that your real subject isn't particularly close to you. It's a rule for landscape shooting.

...My problem is that what does it mean "to focus on a part".

Presently, focus for me means adjusting my focus ring till the image is as clear as it can be. How do i focus on a part exactly.

You don't. You focus on a point. In this case, the point that's 1/3 of the way into the screen. Not the whole bottom 1/3 of the frame.

[cyracles]

I am amazed at the quality of responses am getting here as well as the promptness. Thank you so much all, it's already improving over here and am moving in a positive direction.


@gptwins, the book, Understanding Exposure, where can I get it? I'm Nigerian and such books dont really abound in our bookshops. Are there free copies that can be downloaded, i dont mind ebooks.

Thanks again, when I'm hooked be sure i'll come back for help from the pros.

[SwissJon]

I wouldn't call most of us Pro's, we're jus dumb shmucks who happened to start down this road before you.

because what we do is easily copied and easily redistributed, as you can imagine, most of us are sensitive to piracy, and as such won't promote "free" copies of any paid books, unless they're redistributed by the author or publisher.

The book referred to is this one:

http://www.amazon.co.uk/Understandin...2549375&sr=8-1

I'm sure with those details you can find some way of obtaining it.

Personally I prefer this one:

http://www.amazon.co.uk/Perfect-Expo...ref=pd_sim_b_3

[cyracles]

@SwissJon, I am piracy sensitive too, just did not know if the book was a free online resource or not. Thanks for the clarification and your suggestion about Perfect Exposure.

I am purchasing them as soon as I can, thanks again.