Still confused by aperture

[aaneiros]

Hi. I've been reading this forum a lot and I think I'm starting to understand how my camera works. However, there's still something that puzzles me: aperture.

I think I know the basics (thanks partly to the tutorials I found on this forum): I know that you can use a small aperture number to blur backgrounds and that the bigger aperture number you use, the more stuff will appear on focus in the photo; also I know a smaller aperture number means you are letting more light in.

I've been thinking of three case scenarios where I wouldn't know which aperture to use so I thought I would make them into a question to you, dear readers .

In all three cases lighting conditions are ideal, meaning you get plenty of good light so no need to use smaller aperture numbers to let more light in.

Case 1:

You are on Staten Island ferry and want to take a picture of New York's skyline (you're quite far from the shore)

Case 2:

This time you want to take a child's portrait. He/she is sitting on the ground and some of his/her toys are scattered around (not too far away; say a couple of feet from the model on each side) . You want to take the child and the toys.

Case 3:

You are walking in a wild area and discover some small bird on the branch of a distant tree. You use your mega-zoom lens to take a picture of the bird (a tight crop, just the bird)

So, what aperture number would you use in each case?

Thanks.

Antonio.

 

[table1349]

Perhaps this will help:
Online Depth of Field Calculator
Understanding Depth of Field in Photography
HowTo: Use The Depth-Of-Field Preview On Your Camera | Sublime Light

 

[Compaq]

Case 1:

You are on Staten Island ferry and want to take a picture of New York's skyline (you're quite far from the shore)

Case 2:

This time you want to take a child's portrait. He/she is sitting on the ground and some of his/her toys are scattered around (not too far away; say a couple of feet from the model on each side) . You want to take the child and the toys.

Case 3:

You are walking in a wild area and discover some small bird on the branch of a distant tree. You use your mega-zoom lens to take a picture of the bird (a tight crop, just the bird) .

The first things that come to my mind are these things. (but I'm no expert!)

1.
I don't understand the situation I'm sorry!

2.
I'm assuming you want both the kid and the toys in focus for the shot. What I would do, is to simply use a small enough aperture to get everything in focus. Perhaps you need to take a couple of shots at different apertures. With experience, these things fall more natural, I think.

3. One more thing you must know is that when using a tele lens, your depth of field (DOP) gets shallower. That formulation might not be physically accurate, but what what happens. Also, if you use the longest focal length of your "mega-zoom lens" (hehe), camera shake is just around the corner. Use a small enough aperture so that you get a hand-holdable shutter speed. Usually when taking bird shots, it looks good with the background blurry - sorts of brings the bird out a bit, if you get my point.

Just remember the basic exposure triangle: Aperture - Shutter Speed - ISO

 

[Light Artisan]

Depends, I'd be concerned about shutter speed...

I'd probably try for:
f/11
f/2.8 - f/4
f/2.8

 

[clanthar]

Case 1:

You are on Staten Island ferry and want to take a picture of New York's skyline (you're quite far from the shore)

Case 2:

This time you want to take a child's portrait. He/she is sitting on the ground and some of his/her toys are scattered around (not too far away; say a couple of feet from the model on each side) . You want to take the child and the toys.

Case 3:

You are walking in a wild area and discover some small bird on the branch of a distant tree. You use your mega-zoom lens to take a picture of the bird (a tight crop, just the bird)

So, what aperture number would you use in each case?

I would use a mid aperture value in each case that would maximize the performance of my lens.

Case 1: DOF will be a function primarily of magnification -- f/stop will have little effect so use the f/stop that gives you the best image quality.

Case 2: The toys are on each side of the child and so you don't need lots of DOF -- assuming you're using a small format camera you'll still have plenty of DOF for the child.

Case 3: It's only important to have the bird in focus -- in fact it may be better to only have the bird in focus and so in this case I'd consider opening the aperture maybe a stop, but since you've increased magnification to the point of filling the frame with a bird you're going to get shallow DOF no matter what f/stop you use.

Joe

 

[KmH]

I know that you can use a small aperture number to blur backgrounds and that the bigger aperture number you use, the more stuff will appear on focus in the photo; also I know a smaller aperture number means you are letting more light in.

You also have to take into account

• the lens focal length
• the subject to image sensor distance
• and the subject to background distance.

In #1 the subject is not close to the lens, unless you have part of the ferry in the shot. You should be focusing on the skyline, so you could use a small aperture that still gives sharp focus with the lens you're using.

In #2 as long as the toys are in the same plane that is parallel to the image sensor as the childs eyes are, how far to the sides the toys are is not relevent. What is relevent is that you get the camera down to the childs level and again only use as small an aperture that still gives sharp focus with the lens you use.

In #3 the long telephoto lenses that can open to wide apertures are pretty expensive. Dedicated bird photograpers know spending $10,000 for a 600 mm f/4 lens is just part of the game. If you don't have that kind of money, #3 won't be happening.

 

[djacobox372]

Here's a simple way to think of it: always start the "aperture deduction" process at f8, and then go up and down from there as the shot requires.

This is an extremely simplistic way to think of things, but it helps beginners.

There's an old saying by news photographers on how to get the perfect shot: "F8 and be there," This is based on the fact that almost all lenses perform amazingly at F8, and the dof at f8 is wide enough to encompass most subjects without being too wide.

 

[mrpink]

Hi. I've been reading this forum a lot and I think I'm starting to understand how my camera works. However, there's still something that puzzles me: aperture.

I think I know the basics (thanks partly to the tutorials I found on this forum): I know that you can use a small aperture number to blur backgrounds and that the bigger aperture number you use, the more stuff will appear on focus in the photo; also I know a smaller aperture number means you are letting more light in.

I've been thinking of three case scenarios where I wouldn't know which aperture to use so I thought I would make them into a question to you, dear readers .

In all three cases lighting conditions are ideal, meaning you get plenty of good light so no need to use smaller aperture numbers to let more light in.

Case 1:

You are on Staten Island ferry and want to take a picture of New York's skyline (you're quite far from the shore)

Case 2:

This time you want to take a child's portrait. He/she is sitting on the ground and some of his/her toys are scattered around (not too far away; say a couple of feet from the model on each side) . You want to take the child and the toys.

Case 3:

You are walking in a wild area and discover some small bird on the branch of a distant tree. You use your mega-zoom lens to take a picture of the bird (a tight crop, just the bird)

So, what aperture number would you use in each case?

Thanks.

Antonio.

Wide open, all three.










p!nK

 

[BuS_RiDeR]

Disclaimer: I am not a pro... But this is how I understand it.

Smaller Aperture (bigger F#) = more in focus in front and behind the object in focus...

A big or wide aperture like f1.8 will have very little in focus (case 3).

An aperture set at f8(ish) will allow for more "in focus" around the subject that is in focus... (case 2).

A narrow aperture like f22 will allow for most if not all of your scene to be in focus (case 1).

It'll be a bit different for different lenses.. But this will give you an idea where to start. and you can adjust from there as needed.

 

[Light Artisan]

There's no way I'd want f/22 for number 3.

 

[white]

I've been thinking of three case scenarios where I wouldn't know which aperture to use so I thought I would make them into a question to you, dear readers .

...

So, what aperture number would you use in each case?

I would shoot #1 at f/8 or f/11 because that tends to give the best image quality.

Might shoot #2 at f/2.8, but it depends on the focal length.

Regarding #3, a larger focal length compresses the image, so depth of field could be quite narrow if you're not careful. I'd probably shoot it at f/8.

 

[Compaq]

Disclaimer: I am not a pro...

Your post count beg to differ Congrats on that, cool milestone

 

[JClishe]

Don't get too wrapped up in feeling like you have to know the optimal settings for any given exposure prior to taking the exposure. If you KNOW that you want to blur the background than start wide open. If you KNOW that you want great DoF than start at f/22. If you don't know what you want than start somewhere in the middle (f/8 - f/11). In any case, rip off some pics, view them in the LCD, and adjust settings as necessary.

No one can tell you what the optimal settings for your 3 scenarios are, we can only provide general guidelines. But at the end of the day, it's YOUR exposure and only YOU can determine which combination of settings produces your desired results.

 

[KmH]

Just a quick note;

f/2 is a much bigger number than f/22 is, because they are fractions. :er:

 

[pbelarge]

aaneiros

Try this link, there is some very straight forward, easy to read info here that I believe will help you with this issue.

How Do I Use My Digital SLR?