Any relationship between, Apr. Speed, etc


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John E

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Hi

I am a newbie with a new SLR camera.

I wonder there is any calculation or rule of thumb to getting setting right.

Eg, if I shoot in ISO 100, how they relate to shutter speed, aperture, etc. I shot many times, I just rotate the knob just to hope everything is correct. How do I know e.g if I set Apreture in AV mode, what speed or Iso should I do to get a good shot.

Can a good light meter work all this out for me?

Thanks,

Blur/:dunno::dunno::dunno:
 

google is your friend.
 

I'm not sure what camera you are using but if you notice in your viewfinder that is a gauge that moves left and right depending on the exposure. Best would be to get the needle/line in the center if not left or right depending on what you really want. Play around with apperture mode and you will see the relation between Apperture and Speed. Once you get the hang of it, you can start playing with Manual Mode. =D Enjoy!
 

try to have a shutter speed of at least 1/(focal length)

i.e. @ 50mm, shutter speed is 1/50 :D
 

Thanks. Now I see shutter equal to focal length. How about Aperture and Speed and ISO?

Will Google, but anyone got quick tip, greatly appreciated.

Thanks

:dunno::dunno::dunno:
 

Thanks. Now I see shutter equal to focal length. How about Aperture and Speed and ISO?

Will Google, but anyone got quick tip, greatly appreciated.

Thanks

:dunno::dunno::dunno:

No, you still have it wrong. I suggest you start by reading your manual.

and if you have no idea about the relationship between those factors, why even get a DSLR? Or just shoot in auto mode till you've learned.
 

Nope, there's no maggie-mee solution to understanding the basics of light and the basics of how cameras work. Sorry.

If you want a quick tip, just shoot in Program all the time.

Sorry for being truthful.
 

Hi John E

Shutter speed, ISO, and Aperture forms a triangle, with the light meter at the heart.
The light meter gives u a guide that you based on to adjust the various parameters to achieve your exposure that you want.

Your SLR should have an inbuilt light meter that you can start using and is pretty good for most if not all situations for our typical uses.

Do go through the basic functionalities from the manual to find out more about this meter, the modes, and how to adjust the parameters. Once you are comfortable with basic handling, there are several good online resources for reading up on exposure/aperture/shutter speed/ISO.

Ryan
 

Tweaking speed, apr, temperature, iso etc will produce diff outcome in photos. Some people choose to stick to it once a desired style is achieved, while the creative ones keep evolving.

Unless it's a studio, there's no ideal fixed settings due to change of weather, etc. Once you're there, it'll become clear to you.

For a start, read up more on calculations, settings etc and experiment for yourself.
 

Hi John E,

I'm not entirely sure if its right for me to share this with you, nor if you will fully appreciate it. But here is a mathematical relationship that I charted of Aperture, ISO and shutter speed. As you may know, in my other thread, there has been a heated argument going on about using math for photography. Hope it doesn't start here!

Plug the formula into an excel sheet and start calculating away! Although you will have a much more fruitful experience discovering these for yourself. (Spoiler alert!)

You need to understand the variables I guess, especially step change.

formula.jpg


I shall leave you to figure first. If you find that you don't understand it, but really want to do it the math way, I can further explain a little.
 

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If you had used a film camera before, then one factor - ISO- is taken care of. ISO is the sensitivity of the film - higher more sensitive but more noise. That means if the aperture/shutter speed remains the same, you photo will look brighter in ISO setting of 400 compared to ISO or 100; put another way, ISO 400 allows you to produce a photo of same brightness in dimmer light as one with ISO 100 with brighter light.

Aperture and shutter speed are inversely related. Bigger aperture (smaller f-number) can accomodate faster shutter shutter speed (bigger 1/number) and vice versa. This is because bigger shutter speed allows more light thru for the same amt of time it is open.

If want more bokeh (blurred background) - play with the aperture because it change the depth of field (focus plane) Remember pin-hole camera - if you look thru a pin-hole, you can see things more clearly than a big-hole (pin-hole=bigger depth of field). But bigger aperture will mean more light reaching the sensor at any given time; so in order not to overexpose, you need to restrict light by making the shutter close faster (incr shutter speed).

If you want to freeze an action (eg high jump in mid air) then you should make the shutter speed faster so "time and action is frozen". But having fast shutter speed, means less light can reach the sensor for the short time it is open and hence to allow more light to reach the sensor the aperture must be bigger so that more light passes thru for the duration the aperture is opened.

If you had max the shutter speed and aperture to get that perfect photo but still find the photo is underexposed, then you will have to incr the ISO setting. Higher ISO will make the photo brighter for same amount of light that reached the sensor. However higher ISO tends to produce more noise (unwanted pixel) because it is sensitive to any extraneous light. Remember: if a person is more sensitive (higher ISO), he/she finds more offending collegues! :sweatsm:


Hope this helps. You really need to understand the relationship of these 3 factors before you can get photos of the right exposure and effect. I suggest you fix 2 factors and then play with the third factor to see for yourself the effect. Actually this is the easy part, the more difficult part of photography is the composition... sigh:sweat:
 

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Hi John E,

I'm not entirely sure if its right for me to share this with you, nor if you will fully appreciate it. But here is a mathematical relationship that I charted of Aperture, ISO and shutter speed. As you may know, in my other thread, there has been a heated argument going on about using math for photography. Hope it doesn't start here!

Plug the formula into an excel sheet and start calculating away! Although you will have a much more fruitful experience discovering these for yourself. (Spoiler alert!)

You need to understand the variables I guess, especially step change.

formula.jpg


I shall leave you to figure first. If you find that you don't understand it, but really want to do it the math way, I can further explain a little.

Wah...if i were to take a paper on this, sure fail the exam....kenna kickout...:bigeyes:
 

I'm not entirely sure if its right for me to share this with you, nor if you will fully appreciate it. But here is a mathematical relationship that I charted of Aperture, ISO and shutter speed. As you may know, in my other thread, there has been a heated argument going on about using math for photography. Hope it doesn't start here!

You dare to bring up your darn mathematics and formulas up here ... again?! ;)
 

Thanks for all the comments. Really apprecaite it. At least I have a clearer picture.

Thanks a million!!
 

You dare to bring up your darn mathematics and formulas up here ... again?! ;)

Hahaha! Helped me through my newbie phase, so maybe it will help someone else!


To snowspeeder: This is only sec 3 or 4 maths! Logarithms!
 

Thanks I think with Excel, woulf be easy.

Curiously, is this how the camera calculate in Auto mode? I am sure they have some fixed/safe formula. Also for the Programme setting e.g. Landscape, Potrait etc, surely got some formula..
 

who cares bout the correct formula... when you're there, your eyes becomes a built in lightmeter :bsmilie:
 

Thanks I think with Excel, woulf be easy.

Curiously, is this how the camera calculate in Auto mode? I am sure they have some fixed/safe formula. Also for the Programme setting e.g. Landscape, Potrait etc, surely got some formula..

The camera utilizes a light meter. Basically the 0 step point is a balance of 18% grey. (correct me if I'm wrong!)

The formula I presented you is just the relationship of the 3 factors, a ratio, it doesn't calculate the actual amount of light.

In anycase, if you don't need to be pin precise, you can just use the estimates, it goes something like this:

1 step is worth (either one of):
2x shutter
2x ISO
sqrt (2) = 1.41x F stops

2 steps is worth
4x shutter
4x ISO
2x F stops

Once you get a hang of it, the calculation should be instinctive. Good luck and happy shooting!
 

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