cloudy day

[stevet1]

Let's say I have a cloudy day
In order to let more light into the camera, would I want to set my aperture to around 4 and adjust my shutter speed low to around 1/100th of a second.
Conversely, on a bright, sunny day, would I set my aperture up to around 11 or 16, and increase my shutter speed to around 250 or 500?
I'm using a 70-200 mm lens, and I think 4 is the lowest it will go.

Steve Thomas

 

[stevet1]

So, I've been trying to use the aperture to control the amount of light coming in and then adjusting the shutter speed accordingly.
Should I just use the aperture to control the depth of field and concentrate on using the shutter speed to control the blur and amount of light coming in?

Steve Thomas

 

[weepete]

Let's say I have a cloudy day
In order to let more light into the camera, would I want to set my aperture to around 4 and adjust my shutter speed low to around 1/100th of a second.
Conversely, on a bright, sunny day, would I set my aperture up to around 11 or 16, and increase my shutter speed to around 250 or 500?
I'm using a 70-200 mm lens, and I think 4 is the lowest it will go.

Steve Thomas

Hi Steve,

This totally depends on what your subject is. So in order to determine shutter speed and aperture there was a concept I was introduced to called the limiting factor, which I think may be useful to you.

So in any photo we take there are two main factors that limit our ability to select either shutter speed or aperture. As we decrease shutter speed we can introduce blur if anything in the shot is moving and as we open the aperture (smaller f number) we make our depth of field thinner which can limit what is in acceptable focus.

In any shot we take we can be limited by one, or both.

For example: if we are photograhing a landscape on a tripod on a still day our limiting factor is aperture, as there is little movement in the scene but we want everything from the foreground to the dustance to be in sharp focus. So we'd want to use an aperture value of f8-f11 to maximise our depth of field. So the limiting factor here would be aperture.

If we are shooting say a football game and we want a shot of the quarterback running to catch the ball. Depth of field matters less and as long as they are in focus. So we need the shutter speed to be fast enough to render the quarterback sharp, we may need 1/500th sec - 1/800th sec. The limiting factor here is shutter speed.

If we are shooting say a portait shot of family members on a beach with boats in the background and we want everything sharp, the people are moving, the boats are moving and we want a deep depth of field we might need a shutter speed of 1/100th sec - 1/250th sec and a small aperture of f8-f11 to get everything from foreground to background sharp. The limiting factor here is both shutter speed and aperture.

Things get a little more complicated at the telephoto end (long focal lengths) as depth of field is also limited by distance, so the camera to subject to background distance. If you are close to your subject and there is a large distance between them and the background you may find that at a long focal length you will be unable to get both in focus even at very small apertures, conversely if there is a large distance between you and the subject you may not get much blur on the background even at small apertures. You will find that with extremely long focal lengths like 400-600mm depth of field can be very shallow indeed. It's worth noting that after the aperture hits f16 diffraction starts to kick in which has a slight blurring effect across the whole frame, so normally you don't want to go any smaller than that unless you are shooting macro.

 

[stevet1]

Weepete,

Thanks for your help. I think I understand a little better.
My pictures have tended to be a little overexposed. I think I need to up my shutter speed and shrink my aperture a little more.

Steve Thomas

 

[RVT1K]

So, I've been trying to use the aperture to control the amount of light coming in and then adjusting the shutter speed accordingly.
Should I just use the aperture to control the depth of field and concentrate on using the shutter speed to control the blur and amount of light coming in?

Steve Thomas

This is how I often, but not always shoot.

I'll set the aperture depending on what I want the shot to look like. If I just want the subject and background sharp, I set the aperture smaller (higher number). But if I want the background blurry then I open the aperture up (smaller number).

But if I need to capture something fast moving like hummingbirds, I'll do what ever it takes to get the high shutter speed. That usually means opening the aperture.

But you've not mentioned the third part of the exposure equation and that is the ISO your camera is set to. The higher the ISO the more sensitive it is and the less light it needs to get the same exposure.

So in the case of the hummingbirds, it is often open the aperture and raise the ISO so a fast shutter will allow a proper exposure.

If your camera has an "auto" feature where you mostly point, focus, and shoot, you can experiment a little. Take some shots the way you normally would then set the camera to auto and see what it does. Are the shots better? If so, what did the camera do different than you did?

 

[stevet1]

If your camera has an "auto" feature where you mostly point, focus, and shoot, you can experiment a little. Take some shots the way you normally would then set the camera to auto and see what it does. Are the shots better? If so, what did the camera do different than you did?

RVT1K,

Thank you.
I will take your advice.

Steve Thomas

 

[dennybeall]

One thought that helped a friend of mine was this. You use the light meter on the camera to determine the correct exposure, that's the base setting for thinking.(The Auto Mode would use these settings.) If that won't capture movement then you raise the shutter speed up, BUT if speed goes up then shutter (f-stop) comes down. Direct relationship 1 up then the other down.
Want more depth of field then change aperture and change speed the opposite.
If you run out of settings then change the ISO but remember the higher the ISO the more noise.

 

[Derrel]

You can use The size of the lens opening, the speed of the shutter, or the ISO setting in use to help you to regulate the exposure to get the creative effect that you want. If you wish to have deep, expensive depth of field the small lens openings such as f/11and f/16 offered that. If you wish to have less depth of field, the wide lens openings such as F4 and F/5.6 offer that.

It is often a good idea to use an ISO level that is appropriate to the light level. With a relatively modern digital camera decent pictures are possible at ISO levels that are very low so she is 100 as well as at intermediate levels of roughly up to 800 .

When using a modern camera with A current lens you have a decent built-in light meter. In your situation I assume you are using a legacy lens that the camera does not "see "and so you are having difficulty with what would otherwise be an automated,easy situation.

 

[stevet1]

When using a modern camera with A current lens you have a decent built-in light meter. In your situation I assume you are using a legacy lens that the camera does not "see "and so you are having difficulty with what would otherwise be an automated,easy situation.

That's correct (I think).
I'm using FD lenses on an EF mount, so I have to manually adjust the aperture, and there is no auto focus.
I know when I use the movie setting, the first thing I get is an error message that tells me to attach a lens.
*grin*
It does take you back to the basics, that's for sure.
I'm not sure I even have a light meter, so I'm going to have to read up on that.

Steve Thomas

 

[weepete]

Some old lenses can make your light meter go a bit funky, taking a test shot and learning to read the histogram can help. I trust the histogram now more than my own eyes.

How to Read and Use Histograms

 

[Derrel]

If you have a camera that uses an
EF mount, then you do have some type of light meter. I'm not that familiar with canon but I believe you could use some type of aperture priority metering where the camera will compute the shutter speed for the lens opening in use. Perhaps a more Canon knowledgeable user can reply here. It has been quite a few years since I regularly shot a Canon camera.

Back when I was shooting Canon regularly, I experimented for about a year or so with using off brand lenses on adapters on my 20D and my 5D.

 

[stevet1]

Some old lenses can make your light meter go a bit funky, taking a test shot and learning to read the histogram can help. I trust the histogram now more than my own eyes.

How to Read and Use Histograms

Weepete,

From the article you referenced:
"To do this with a Canon press “Display” or “Info” button (depends on your model), until they show up on the screen when previewing images. You also may need to turn on this feature in the menu settings. Check your camera’s manual if you aren’t sure where to find it."

I'm assuming this means I can look at the histogram prior to taking the shot?
That would be a nice ability to have.

Steve Thomas

 

[weepete]

Some old lenses can make your light meter go a bit funky, taking a test shot and learning to read the histogram can help. I trust the histogram now more than my own eyes.

How to Read and Use Histograms

Weepete,

From the article you referenced:
"To do this with a Canon press “Display” or “Info” button (depends on your model), until they show up on the screen when previewing images. You also may need to turn on this feature in the menu settings. Check your camera’s manual if you aren’t sure where to find it."

I'm assuming this means I can look at the histogram prior to taking the shot?
That would be a nice ability to have.

Steve Thomas

I can on mine so I'm assuming yours will be similar, if you put your camera into live view and press info three times, but you can also just snap a quick shot and press the review image button then info twice for similar settings