Shutter speed / Aperture

[bigmark100]

Hi guys. Excellent forum. Looking foward to participating and learning.

I'm rather new to photography, and am lucky enough to have got myself some nice equipment. ie A Canon 40D, 50mm 1.4 , 24-70mm 2.8L .
Ive been shooting with this for about 6 months.
I'm getting on nicely - I mostly shoot in AV mode. Ive learnt how to use the aperture to control DOF , and have got some good results with this.
But this is the only mode I use.

I have no idea of when to use Shutter Priority (Tv), and why I would use this over Av. Okay - occasionally I use Tv when its night time , and I want to take a night shot in low light, but to be honest - I dont understand using the shutter....

I do understand the use of Aperture/Shutter and ISO in order to improve my shots according to light..... but normally I just use trial an error...
ie - keep pumping up one of these until I get a satisifactory result.

how can I learn more about and understnad more about Av/Tv and when its best to use one over another....?


any tips or links to help me would greatly be appreciated.

thanks
Mark

[PaulG]

Hi Bigmark

I think the best idea would be for you to visit your local library and initially read up on lens functionality. In trying to give advice there would be the need to know what type of photography you are interested in and what preferences you have. Basically a small aperture will give you more depth of field (DOF) ie more of the image will be in focus from the foreground to the background. A larger aperture will restrict the DOF. A fast shutter speed will enable you to freeze an action shot usually without blurring. The balance within the camera will be if you use a large aperture then a faster shutter speed will be selected and visa versa. Initially I wouldn't use a speed of less than 1/60 so that you will avoid camera shake.

Paul

[george.monaghan]

Hi,

You would need to control shutter speed when you want to "freeze" the action or allow it to "flow" and blur.

A fast shutter speed normally gets rid of camera shake that slower speeds show when your pictures are enlarged. Many OOF pictures are in fact "camera shake".

So, when speed is of the essence let the DOF look after itself. In P mode the camera will change these settings depending on which dial you use to alter the exposure. Experiment and you will see the difference. Faster shutter speeds usually mean sharper pictures when hand holding. Presuming the focus is OK though.

[canonman]

Hi guys. Excellent forum. Looking foward to participating and learning.

I'm rather new to photography, and am lucky enough to have got myself some nice equipment. ie A Canon 40D, 50mm 1.4 , 24-70mm 2.8L .
Ive been shooting with this for about 6 months.
I'm getting on nicely - I mostly shoot in AV mode. Ive learnt how to use the aperture to control DOF , and have got some good results with this.
But this is the only mode I use.

I have no idea of when to use Shutter Priority (Tv), and why I would use this over Av. Okay - occasionally I use Tv when its night time , and I want to take a night shot in low light, but to be honest - I dont understand using the shutter....

I do understand the use of Aperture/Shutter and ISO in order to improve my shots according to light..... but normally I just use trial an error...
ie - keep pumping up one of these until I get a satisifactory result.

how can I learn more about and understnad more about Av/Tv and when its best to use one over another....?


any tips or links to help me would greatly be appreciated.

thanks
Mark

Hi Mark,

I posted this a while back, and hopefully it should help straighten out a few things for you!? Where I refer to shutter speed priority, that is the TV setting, aperture priority is the AV setting.

If like many you are fairly new to the world of digital SLR photography, or you have a "bridge" type camera with dials and settings you don't understand, then perhaps this may help a little ?

The very fact that you have invested in a camera with controls, would suggest that you are looking to achieve more with your picture taking. To get the best from it, you now need to invest in time and research to begin to really understand the basics of image capture. I am also assuming a basic level of understanding with regard to light levels, and the basic function of a cameras light meter. If unsure about this, I would suggest that as your first piece of research.

My first recommendation is to switch off the fully automatic mode on your camera, and don't switch it on again unless in a panic situation where you just want to be sure of getting a shot, and you have no time to think !

The two operating modes I will talk about here are "aperture priority" and "shutter speed priority". If either of these terms leave you confused, then stop reading this and go and do some research about the basic mechanics of a camera. Those still reading I assume understand "what" the terms mean, but not necessarily "why" there are these specific modes, or "how" to decide which you need to select. I will attempt to give a quick guide to the decision making journey to embark upon prior to selecting the correct mode.

"Shutter Speed Priority"
1. If you are hand holding your camera, there is a simple guide-line to ensure that images don't end up blurred as a result of camera shake (different formula for the new-age digital specific camera/lens kits). Whatever focul length of lens you have on the camera, should be the minimum shutter speed that you capture the image with. This is assuming you have a DSLR with full-frame sensor. It is important that you find out about the "multiplication factor" of your camera sensor. If you have a sensor with a 1.6x factor then this is the formula. Multiply the focul length of your lens by 1.6, that is the minimum to be safe hand-held speed (unless you have an image stabilised lens) for your shot. The longer the lens the more important this becomes, and the faster the shutter speed required.
2. The subject matter is your next considoration. If the subject is moving, or contains movement, the speed of the shutter will effect the outcome. Fast moving objects require fast shutter speeds to "freeze" the action. A slower shutter speed will leave the same moving object blurred. This decision is dependent on how you visualise the outcome. Only experimentation will tell you what actual speeds work to give the desired effect.

"Aperture Priority"
1. The size of the aperture on a lens has a dramatic effect on the focussing capabilities of a lens. If you don't understand "exactly" what is meant by "depth of field", it is very important that you familiarise yourself with this term. The "f" number on a lens denotes the aperture size, and just to confuse you, the higher the number the smaller the aperture! A small aperture gives the greatest depth of field. Obviously a large aperture will give a small depth of field. The overall relationship between shutter speed and aperture size is this. A small aperture (bigger "f" number) allows the least amount of light into the camera and will require a longer exposure (slower shutter speed). A large aperture (small "f" number) allows a lot of light into the camera, and will require a relatively shorter exposure (faster shutter speed).
2. Be aware that large aperture sizes by nature (reduced depth of field) require far more critical focussing, but can be used to fantastic creative effect.

To summarise, the correct exposure is a balancing act between your physical limitations ( Hand held or supported ,relating to focul length, moving or static subject matter), the desired effect and of course the amount of available light. It is the assessment of these factors, knowing exactly what you are attempting to achieve and thus an understanding of what needs to be the "priority", which lets you set the appropriate "priority mode".

The above outlines the principals as simply as I am able to do so. Any able photographer knows this all off by heart. Making this become second-nature is a fairly good grounding as an introduction to more serious photography.

Enjoy !!

[bigmark100]

thanks very much..... that makes things much clearer.

[Manamarak]

Mark,


how can I learn more about and understnad more about Av/Tv and when its best to use one over another....?


any tips or links to help me would greatly be appreciated.

I hope these can be of help:

( no links sorry)

It is a small selection of articles I wrote about the basics of digital photography, and it covers everything from depth of field, shutter speed, how to shoot in auto or manual, and how to get your exposure right.

Hope that's the sort of thing you are looking for.

47561

[canonman]

Hi guys. Excellent forum. Looking foward to participating and learning.

I'm rather new to photography, and am lucky enough to have got myself some nice equipment. ie A Canon 40D, 50mm 1.4 , 24-70mm 2.8L .
Ive been shooting with this for about 6 months.
I'm getting on nicely - I mostly shoot in AV mode. Ive learnt how to use the aperture to control DOF , and have got some good results with this.
But this is the only mode I use.

I have no idea of when to use Shutter Priority (Tv), and why I would use this over Av. Okay - occasionally I use Tv when its night time , and I want to take a night shot in low light, but to be honest - I dont understand using the shutter....

I do understand the use of Aperture/Shutter and ISO in order to improve my shots according to light..... but normally I just use trial an error...
ie - keep pumping up one of these until I get a satisifactory result.

how can I learn more about and understnad more about Av/Tv and when its best to use one over another....?


any tips or links to help me would greatly be appreciated.

thanks
Mark

Mark, I've just copied and pasted this guide that I posted here a while a go, I hope it can help you a little !?

If like many you are fairly new to the world of digital SLR photography, or you have a "bridge" type camera with dials and settings you don't understand, then perhaps this may help a little ?

The very fact that you have invested in a camera with controls, would suggest that you are looking to achieve more with your picture taking. To get the best from it, you now need to invest in time and research to begin to really understand the basics of image capture. I am also assuming a basic level of understanding with regard to light levels, and the basic function of a cameras light meter. If unsure about this, I would suggest that as your first piece of research.

My first recommendation is to switch off the fully automatic mode on your camera, and don't switch it on again unless in a panic situation where you just want to be sure of getting a shot, and you have no time to think !

The two operating modes I will talk about here are "aperture priority" and "shutter speed priority". If either of these terms leave you confused, then stop reading this and go and do some research about the basic mechanics of a camera. Those still reading I assume understand "what" the terms mean, but not necessarily "why" there are these specific modes, or "how" to decide which you need to select. I will attempt to give a quick guide to the decision making journey to embark upon prior to selecting the correct mode.

"Shutter Speed Priority"
1. If you are hand holding your camera, there is a simple guide-line to ensure that images don't end up blurred as a result of camera shake (different formula for the new-age digital specific camera/lens kits). Whatever focul length of lens you have on the camera, should be the minimum shutter speed that you capture the image with. This is assuming you have a DSLR with full-frame sensor. It is important that you find out about the "multiplication factor" of your camera sensor. If you have a sensor with a 1.6x factor then this is the formula. Multiply the focul length of your lens by 1.6, that is the minimum to be safe hand-held speed (unless you have an image stabilised lens) for your shot. The longer the lens the more important this becomes, and the faster the shutter speed required.
2. The subject matter is your next considoration. If the subject is moving, or contains movement, the speed of the shutter will effect the outcome. Fast moving objects require fast shutter speeds to "freeze" the action. A slower shutter speed will leave the same moving object blurred. This decision is dependent on how you visualise the outcome. Only experimentation will tell you what actual speeds work to give the desired effect.

"Aperture Priority"
1. The size of the aperture on a lens has a dramatic effect on the focussing capabilities of a lens. If you don't understand "exactly" what is meant by "depth of field", it is very important that you familiarise yourself with this term. The "f" number on a lens denotes the aperture size, and just to confuse you, the higher the number the smaller the aperture! A small aperture gives the greatest depth of field. Obviously a large aperture will give a small depth of field. The overall relationship between shutter speed and aperture size is this. A small aperture (bigger "f" number) allows the least amount of light into the camera and will require a longer exposure (slower shutter speed). A large aperture (small "f" number) allows a lot of light into the camera, and will require a relatively shorter exposure (faster shutter speed).
2. Be aware that large aperture sizes by nature (reduced depth of field) require far more critical focussing, but can be used to fantastic creative effect.

To summarise, the correct exposure is a balancing act between your physical limitations ( Hand held or supported ,relating to focul length, moving or static subject matter), the desired effect and of course the amount of available light. It is the assessment of these factors, knowing exactly what you are attempting to achieve and thus an understanding of what needs to be the "priority", which lets you set the appropriate "priority mode".

The above outlines the principals as simply as I am able to do so. Any able photographer knows this all off by heart. Making this become second-nature is a fairly good grounding as an introduction to more serious photography.

Enjoy !:)