# Aperture/Shutter speed/ISO



## lordsn (Mar 17, 2013)

How well could one explain the relation used while choosing the correct aperture, shutter speed and ISO?


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## Mt Spokane Photography (Mar 17, 2013)

Its a skill based on experience and based on the subject, the light levels, and the capability of your camera and lens.


The photographer decided on the look he wants, and tries to get it within the limitations presented to him.


There is no simple rule of thumb.


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## digital paradise (Mar 17, 2013)

First you typically want the lowest ISO for your application. Second you need the fastest shutter speed to be able to avoid camera shake and freeze you subject. Sports you want a fast shutter. 1/1000 or better. Someone sitting 1/60 will do. Rule of thumb for avoiding camera shake is shutter should be be one stop faster than the focal length. 50mm = 1/60. 300mm = 1/320. YOu can lower that a bit if your lens has IS. I usually always go much higher. Better for me.

Next is DOF which you control via the aperture. Shallow or deep. Shallow means a persons face is in focus and everything is out of focus. Deep means everything in the image is in focus. Shallow = 1.4. Deep = 16. Here is where you are creative. Not to say you can't be creative with shutter speeds. You may want motion blur.

DOF calculator. Distance to subject is very important when you are shooting shallow. 

http://www.dofmaster.com/dofjs.html

I will always sacrifice ISO and aperture if I want to freeze my subject. I can fix noise from high ISO and I can live with a blurred background if my subject is in focus if I need to open up the aperture to maintain shutter a fast speed. You can not fix a blurry, OOF image.

Everything above is a slave to exposure. You have to keep the camera's light meter in the middle - for starters. Later you need to learn how your camera meter works. How to expose for back lit subjects, how to expose for pure black or pure white subjects. Those are extremes but you need to know that. A 50% black and 50% white subject will expose properly when the meter is in the middle. 

Play with this for a while and you will start to get the hang of it. 

http://camerasim.com/camera-simulator/


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## digital paradise (Mar 17, 2013)

Forgot. Every time you make the shutter faster, close down the aperture (16 to 1.4) or both you let less light getting in to the sensor. Reversed when you slow the shutter down or open the aperture. Need to pay attention to the light meter. If you can't get it in the centre for what you want to increase or decrease the ISO.


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## RS2021 (Mar 17, 2013)

digital paradise said:


> I will always sacrifice ISO and aperture if I want to freeze my subject. I can fix noise from high ISO and I can live with a blurred background if my subject is in focus if I need to open up the aperture to maintain shutter a fast speed. You can not fix a blurry, OOF image.



Just the additional stops of ISO that the newer bodies offer, in and of itself, is a big leap...it allows you a lot of lattitude that one never had shooting events in the film era. 

The post processing software advancement also vastly improves the modern photographer's ability to fix in post what was not acheived in the original exposure...this is above and beyond what one could do during printing in the film era, particularly with traditional lab color processing. And all that in a much less cumbersome and inexpensive process now...

Magical times indeed.


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## bdunbar79 (Mar 17, 2013)

Since I mainly do sports, I'll offer what I do. 1/1000s is NOT the minimum shutter speed for sports, it's more like 1/500. Anyways, for sports I always go to freeze action FIRST, via shutter speed, at slowest 1/500 and any faster I can do, well, even better. I next consider isolating the subject and all of my sports photography is player-centric since that's what I was hired to do; get 8 x 10's of individual players in action. So I then set aperture to as wide as I can within reason, such as not to make the DOF way too thin, but also not too deep. So really, f/2.8 to f/4 is typically pretty good. Last, I ETTR by +2/3 to +1 stop via CWA metering, so ISO is last. Whatever ISO I need to do that at my chosen shutter speed and aperture is what the ISO is. And technology has allowed us to do that. For instance, in toughest shooting conditions, I was 1/500, f/2.2, ISO 5000. In very easy conditions, for outdoor soccer, I could do 1/3200, f/3.2, ISO 400.


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## digital paradise (Mar 18, 2013)

Each to his own but I think that is border lien. I was maxed out on my 7D. Night game, F4 lens and at 12,800 I could only get to 1/500. Hands and feet have motion blur. I wish I could have prevented this with a higher speed. You can create prop blur on a plane at 1/320.


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## Mt Spokane Photography (Mar 18, 2013)

As you note from the comments, each has his own need, and has to deal with equipment limitations. I'd suggest taking a online photography course, or getting a good book, there are just too many special situations to generalize.


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## DCM1024 (Mar 18, 2013)

Mt Spokane Photography said:


> As you note from the comments, each has his own need, and has to deal with equipment limitations. I'd suggest taking a online photography course, or getting a good book, there are just too many special situations to generalize.



+1

Before anyone can recommend settings, you need to decide what type of photo you are taking. Do you want a portrait with a blurred background? Choose a wide open aperture then set shutter speed and iso to get a correct exposure.

Motion? Do you want to freeze motion (fast shutter speed) or blur it (soft flowing water effect, slow shutter speed)? Set that first, then choose the aperture and iso to get a correct exposure.

It's a balance of aperture, shutter speed and iso which you must choose independently for each desired effect.


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## bdunbar79 (Mar 18, 2013)

digital paradise said:


> Each to his own but I think that is border lien. I was maxed out on my 7D. Night game, F4 lens and at 12,800 I could only get to 1/500. Hands and feet have motion blur. I wish I could have prevented this with a higher speed. You can create prop blur on a plane at 1/320.



This is where technology comes in to help. A lens that goes f/2.8 lowers your ISO automatically from 12,800 to 6400. And if you have yet a camera that handles super high ISO's, 6400 is easy and now you have a very clean photo. You could then raise shutter back up to 1/800 and shoot at ISO 10,000 and still have very acceptable files. This is an extreme example, however. Looking at your file, though, I think you did very well.


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## wickidwombat (Mar 18, 2013)

Sunny 16 rule?

probably sums up what you are looking for best


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## digital paradise (Mar 18, 2013)

bdunbar79 said:


> digital paradise said:
> 
> 
> > Each to his own but I think that is border lien. I was maxed out on my 7D. Night game, F4 lens and at 12,800 I could only get to 1/500. Hands and feet have motion blur. I wish I could have prevented this with a higher speed. You can create prop blur on a plane at 1/320.
> ...



I did not have a 2.8 lens telephoto at the time or I would have used it. Used my 300 F4 IS. The term fast lens really hit home that night. I just picked up the new 70-200 2.8


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## digital paradise (Mar 18, 2013)

Actually the suggestions about taking some courses is very good. I did that in 2005 and they were very helpful. Film was expensive so I used to just shoot in program mode. Instant results with digital and at virtually no cost really changed things. Very cool when you get over the peak of this learning curve. I don't think I could go back to being stuck with only one ISO. 

Same goes for flash. I was asked to shoot a wedding about 4 years ago so that forced me to take lighting courses which were terrific.. Nice to control your equipment instead of our equipment controlling you.


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## SwissBear (Mar 18, 2013)

Oh how I praise the digital age! All I did was understanding the concept of DOF, and after that I played around with Av/Tv and I got a feel for ISO performance (on my rebel: up to 400 is good, 800&1600 are acceptable if not printed).

What also helps is to team up with someone, I have an uncle who started photographing way back in the analogue age, so he has all the knowledge i crave for (=

From a mathematical point of view, its a single equation with three unknowns, so the solution is only a relation between the three unknowns.

If you hit the limits of your gear ISO- or shutterspeed-wise: always remember that you can easily underexpose 1-2 stops (if shot in RAW) and push it back to normal in post. On the other side (too much light) it's a bit worse, overblown highlights are more critical.


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## Sporgon (Mar 18, 2013)

lordsn said:


> How well could one explain the relation used while choosing the correct aperture, shutter speed and ISO?




Really you are asking about the fundamental building blocks of photography.

No one is going to be able to answer this fully in a web post.

Get a good book on the fundamentals of photography. I can't recommend any because the ones I remember are now really old, but I'm sure there are CR members who can point you to the best books.


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## Dylan777 (Mar 18, 2013)

Since I'm not a big fan of tripod, my priorities are:

1. Lowest ISO
2. Shutter Speed
3. Aperture

Of course there is no right or wrong here - just personal ref.


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## Rienzphotoz (Mar 18, 2013)

lordsn said:


> How well could one explain the relation used while choosing the correct aperture, shutter speed and ISO?


What you are asking has taken me years to learn (I have to admit that I am a bit slow) ... the "relation" is extremely dynamic ... it is one thing for a landscape photographer who always uses a tripod and it is completely different thing for a run and gun sports photographer who wants to freeze action. Like others have suggested take time to learn the fundamentals of photography. There are lots of free tutorials on youtube you can learn from or you can subscribe to "Lynda.com" or "Kelbytraining.com" etc alternatively you can also learn live on the internet for free with "CreativeLive.com", they have quite a few great photographers who teach online and you can ask them questions live on the show, all you need is an internet enabled device to be online for their live classes ... they have a course called "Fundamentals of Digital Photography 2013" by John Greengo which you can also purchase ... there is also one from Lynda.com called "Foundations of Photography" by Ben Long ... these are just a few I know and learned from but I'm sure there are tonnes of other great tutorials by some great instructors.


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## J.R. (Mar 18, 2013)

Dylan777 said:


> Since I'm not a big fan of tripod, my priorities are:
> 
> 1. Lowest ISO
> 2. Shutter Speed
> ...



Interesting ... My priorities are opposite - I choose shutter speed and aperture over ISO.


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## RLPhoto (Mar 18, 2013)

1. Aperture
2. Shutter-speed
3. ISO

Usually in that priority, but If working with flash

1. Shutter-speed (More specifically Sync Speed)
2. Aperture
3. ISO


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