Tv, Av modes - DPChallenge Forums

04/28/2005 05:44:35 PM · #1

Av mode lets you change the aperturte priority right?
An Tv mode just lets you adjust the exposure?
Are these things correct?

04/28/2005 05:45:11 PM · #2

Originally posted by Discraft:

Av mode lets you change the aperturte priority right?
An Tv mode just lets you adjust the exposure?
Are these things correct?

Both change the exposure.

Av = aperture priority
Tv = shutterspeed priority

Message edited by author 2005-04-28 17:45:37.

04/28/2005 05:46:30 PM · #3

learn Manuel mode (M), you will be much happier.

04/28/2005 05:47:26 PM · #4

Originally posted by swinging_johnson_v1:

learn Manuel mode (M), you will be much happier.

There's a purpose for all modes.

04/28/2005 05:47:37 PM · #5

yes i always use manual mode but i am just wondering... so what i said is correct right?

04/28/2005 05:48:22 PM · #6

Originally posted by Discraft:

yes i always use manual mode but i am just wondering... so what i said is correct right?

Not exactly. Read my first post.

04/28/2005 05:48:45 PM · #7

Originally posted by cpanaioti:

Originally posted by swinging_johnson_v1:
learn Manuel mode (M), you will be much happier.

There's a purpose for all modes.

yes, but manuel mode does not take thing into consideration. Manuel mode is strictly up to the user, not visa versa.

theSaj

Canon EF 70-200mm f/2.8L IS USM

04/28/2005 05:48:55 PM · #8

Tv mode....????

You mean that's NOT for the TV output....???

j/k

But I am curious, how the Tv & Av terminology came about. Av I can at least see "aperture" (not sure where the v comes from) and Tv (maybe time???)

Curious....anyone know?

04/28/2005 05:51:55 PM · #9

aperature value and time value.

Canon RF 24-70mm f/2.8 L IS

04/28/2005 05:52:42 PM · #10

Originally posted by swinging_johnson_v1:

Originally posted by cpanaioti:

Originally posted by swinging_johnson_v1:
learn Manuel mode (M), you will be much happier.

There's a purpose for all modes.

yes, but manuel mode does not take thing into consideration. Manuel mode is strictly up to the user, not visa versa.

Yes that i know... i only use that... but i just wanted to make sure..
Thanks a lot.

kirbic

Canon EOS R5

04/28/2005 06:57:42 PM · #11

According to the 10D manual...

Av = "Aperture Value"
Tv = "Time Value"

In Av mode, you select the aperture you want, and the camera will not change it. The camera changes the shutter speed to get the correct exposure.

In Tv mode, you select the shutter speed that you want, and the camera leaves it alone, but selects the proper aperture ot get the correct exposure.

zeuszen

Canon EOS-1Ds Mark II

Canon EF 24-105mm f/4.0L IS

04/28/2005 07:57:15 PM · #12

In aperture priority (Av), the shutter speed fluctuates. which makes it difficult to freeze motion but easy to determine depth of field.

In shutter priority (Tv), the aperture fluctuates, which makes it easy to freeze motion and difficult to determine depth of field.

When the light is good and I have no time to consider finesse but need to get the shot, I set my camera to Tv at 1/1000 sec and shoot everything in sight at this setting.

04/28/2005 08:03:34 PM · #13

Thanks for the explanaition... I had an ideia of this but i wanted to be certain of this since i never gave very much uso to these modes... I will have a try at them especially Tv mode so i can freeze the action especially on bird shots... or should i not do this?

04/28/2005 08:05:11 PM · #14

Originally posted by swinging_johnson_v1:

learn Manuel mode (M), you will be much happier.

Erm - but surely I will want a fast or slow shutter, and open or closed aperture, but almost always balanced within the constraints of my lens and film speed. Manual is useful when doing something out of the ordinary, but Av and Tv, along with the exposure dial, get you taking photos faster. Unless your point is to take them more slowly and thoughtfully?

Canon RF 24-70mm f/2.8 L IS

04/28/2005 08:08:28 PM · #15

What makes a photo sharper the aperture or the shutter?
I know shutter helps to stop the movement when things are moving fast but does the aperture really help to make the shot sharper?

kirbic

Canon EOS R5

04/28/2005 08:17:24 PM · #16

Originally posted by Discraft:

What makes a photo sharper the aperture or the shutter?
I know shutter helps to stop the movement when things are moving fast but does the aperture really help to make the shot sharper?

At their widest aperture, most lenses are not as sharp as when "stopped down". The "sweet spot" where the lens is sharpest does vary, but f/5.6 to f/11 are good bets. With apertures smaller than f/16, things can start to get softer again, for different reasons (diffraction).

The required shutter speed to get a sharp shot varies with the amount of subject motion and the amount of camera shake (affected by the focal length. To minimize the effect of camera shake, shoot at a shutter speed equal or faster than 1/focal length (example: 1/200 or faster for a 200mm lens).
For static people shots, subject motion is not a big problem with shutter speeds of 1/50s or faster, but for action shots of people, you might need 1/500s to get a sharp shot. You just need some experience to know.

04/28/2005 08:20:08 PM · #17

As I understand it, aperture affects Depth of Field. Shutter speed affects degree of motion blur on moving subjects. Lack of sharpness can be caused by either. Plus quality of the optics.

As photographer, you must balance available Av and Tv within their boundaries: Maximum Av stop on your lens, fastest shutter speed on your body, and ISO rating of your sensor.

Fast shutter speed is essential for stopping the action, but to get proper exposure at fast speeds, you will need to open up your lens (giving you shallower DoF), or use a higher/faster ISO. When those are maxed out, any shutter speed that is too fast will result in under exposure.

For maximum DoF (focus from front to back of your image) you will have to keep your Av number high - a smaller aperture - and keep the shutter open for longer to compensate (or make the sensor more sensitive by using a higher/faster ISO).

Higher ISO is often useful for these reasons - but the compromise is more grain (also leading to loss of sharp detail) at higher ISO levels.

All a balancing act. In "M" mode, you can do all the balancing. In Av or Tv, you specify one of the values and the camera will try and balance the others for you (as far as possible) to achieve a correct exposure by the camera's measurements.

edit - typo

Message edited by author 2005-04-28 20:22:19.

04/28/2005 08:21:49 PM · #18

Originally posted by legalbeagle:

Originally posted by swinging_johnson_v1:
learn Manuel mode (M), you will be much happier.

Erm - but surely I will want a fast or slow shutter, and open or closed aperture, but almost always balanced within the constraints of my lens and film speed. Manual is useful when doing something out of the ordinary, but Av and Tv, along with the exposure dial, get you taking photos faster. Unless your point is to take them more slowly and thoughtfully?

My point is that Manuel mode lets you be more precise.

Like zeuszen said, if you know what the shot is, time is significant, and you are comfortable with the camera dertermineing your dof, then go for it.

I like to determine my image quality beforehand, and don't let my camera make decisions for me generally.

04/28/2005 08:24:28 PM · #19

Originally posted by swinging_johnson_v1:

and you are comfortable with the camera dertermineing your dof, then go for it.

Surely though on Av mode you are substantially in control of the DoF. Only issue would be if you wanted a faster shutter action and did not mind/wanted the under exposure? In which case, you can dial in under exposure or use M mode.

04/28/2005 09:20:19 PM · #20

Originally posted by legalbeagle:

Originally posted by swinging_johnson_v1:
and you are comfortable with the camera dertermineing your dof, then go for it.

Surely though on Av mode you are substantially in control of the DoF. Only issue would be if you wanted a faster shutter action and did not mind/wanted the under exposure? In which case, you can dial in under exposure or use M mode.

Exactly.

Message edited by author 2005-04-28 21:20:53.

04/28/2005 09:21:47 PM · #21

again, manuel mode lets you be more precise.

Legalbeagle, You seem to have a handle on your camera (nice pix), so why the questions.

Message edited by author 2005-04-28 21:22:41.

04/29/2005 12:51:14 PM · #22

Originally posted by swinging_johnson_v1:

again, manuel mode lets you be more precise.

Legalbeagle, You seem to have a handle on your camera (nice pix), so why the questions.

Just don't understand why you would use manual mode in most situations. [Think I saw you refer to using manual focus in another thread. Just strikes me as crazy - you don't have the viewfinder matting necessary to get the focus as good as the autofocus on a modern SLR.] I think that Manual mode is really only beneficial in very limited situations. Such as setting Tv for bulb and choosing your Av.

See you have the background in filmic business, but I don't think that recommending M mode to someone who does not understand the basics is necessarily useful. Learning is best (I think) on Av mode as you cannot substantially under or (on a fast-ish body) over expose your images by mistake. You can experiment with different Av settings to see the difference. See the effect on Tv. See the effect of changing ISO. And only when you are used to certain light levels, and Av and Tv modes, try guessing your own in Manual (or see if you prefer using out of body lightmeter). Just my thoughts.

Message edited by author 2005-04-29 12:54:08.

04/29/2005 12:58:33 PM · #23

the peramiters of AF, and AV, and TV are preprogrammed within the camera.

You have a nice camera, do you use your histogram, or do you bracket?

If you don't are you saying that these are not important tools?

AGAIN, Manuel mode (M) gives you precision, and overrides any preprogrammed considerations that the manufacture thinks is what you should be doing with your pix.

It puzzles me why anyone would buy a $1500 camera, and let the camera make the decisions for you. You could of done the same thing with a point and shoot for much less money.

That is all I am saying.

04/29/2005 01:05:46 PM · #24

Originally posted by swinging_johnson_v1:

It puzzles me why anyone would buy a $1500 camera, and let the camera make the decisions for you. You could of done the same thing with a point and shoot for much less money.

But surely, I have bought a $1500 camera with multiple exposure modes, fast AF with multiple microchip control for the automatic modes, rather than a P&S because I want something more than a $200 P&S, which has evaluative metering and no choice on Av and Tv beyond certain preset patterns.

As for compromise - Av gives you the full range of stops available for your camera, and sets the Tv for you at the correct speed, taking into account the metering method used, flash lock, ISO speed, flash focal length. Tv gives you the full range of shutter speeds, and sets the Av for you accordingly with the same considerations. So there is no "compromise" with Av and Tv. Are you thinking of the "portrait" mode, and "landscape" mode etc?

ganders