Is the math really necessary

[Spinners]

Ok, this may seem like a stupid question, but being a newbie, and really wanting to get good shots.. I am wondering if all this math i keep seeing about DOF, COF, and focal planes, and such is actually going to help me take better pictures.. Do you professionals make all these calculations every day? or is this just photo geek theory..

I am a computer programmer/network administrator, and they told me i needed to be good at math to program, and be good at computers.. well they were wrong. So i ask.. Is this really going to help me.

Because im really getting confused.!!!


if it's in focus .. who cares.. ??

[CyberDyneSystems]

I don't know a thing about math and cameras :D

My Camera tells me when the exposure is correct,. and someties I push it over or under,. for a desired effect,.. but i don't know the math.

In fact, I lent my camera (10D) to a "Photographer" who knew all of the above once,. simply because I had a lens that worked better in lower light,.. She had her pro meter out and spent all this time working out stuff,.. set the camera to full manual (the first time that particular camera had ever been set to "M" )

Well,. every one of her pictures was COMPLETELY blown out/over exposed.

Seems all the math she did was for ISO 100,.. the camera was still set at ISO 800... :(

If she had used the autoexposure or a priority setting (or just been more familiar with the camera I admit) the pics would have been fine.

Knowing the basics will help you get better pictures in the long run I'm sure,. but isn't great that Canon will do the math for us?

[soumya63]

Dear CyberDyne,

Can not help but say if life was that simple

I have done some math to capture images like this

http://www.mitraphoto.com/photographs/landscapethm11.jpg

I do not think you may get any close to this image exposure or Depth of Field wise in the P mode.

Soumya Mitra
www.mitraphoto.com

[CyberDyneSystems]

:)

You read me wrong!

...... no,. I was unclear! :(

I did say "... Knowing the basics will help you get better pictures in the long run ..."

I really believe that,.. personally I'm not there yet,.. But I am learning....

.... My 10D has now been set to "M" many times since then,.. and I still forget about the ISO settings myself!!!! :(

I SHOULD have said "... in the meantime..." before that part about Canon doing the math!!!!!

But in my own defence ,.. you can use trial and error with the settings when auto is no good.... since we aren't buying film,.. :D :D

[Yance]

For average pictures it shouldn't matter, the camera is smart enough to figure them out. Also you can always preview your pictures to find out if you are getting the effect you want. That's the great thing about digital. Eventually you will either learn the rules by trial and error or you'll tae a class or read some books to pick it up.

[perfectpixel]

soumya63 wrote:

I have done some math to capture images like this


what math did you use to get that particular exposure? and where would P have gone wrong (usually)?

[Roger_Cavanagh]

You don't need to know the math, but if you understand the principles you will be more in control of your camera. Stuff like: you're taking a portrait, what should you do to isolate the subject from the background; you're taking landscapes, what's the best way to ensure that the greatest amount of the picture will be in focus; you're shooting a subject that is heavily backlit, what should you do.

The DSLR is like any tool, the more the understand what you are doing and how to use it, the less will be your dependence on luck to get good results.

The great thing about a DSLR is you can practice to your heart's content and it doesn't cost you a penny.

Regards,

[robertwgross]

I agree. You don't need to do a lot of math calculations on a daily basis, but you do need to think about the principles of what you are doing. It is good to go through the calculations just a bit when you are in the learning stage, so that you understand why things inside the camera have to be the way that they are. Then, with a rather nice camera, you can let the camera do its thing for normal shots. As you beging to get more creative, you have to think a little more. As you get into a really difficult shot, you may have to think a lot more. If you understand the basics, then the thinking is easy and will produce the right result.

I think an understanding of light physics and electronics is somewhat more helpful than a trunkful of math calculations.

Geez, with digital you can just keep trying something else until you get the necessary result.

---Bob Gross---

[CyberDyneSystems]

Roger_Cavanagh wrote:

...The DSLR is like any tool, the more the understand what you are doing and how to use it, the less will be your dependence on luck to get good results....


Regards,

This makes sense,..


....most people know how to use a table saw to rip a 1X8 peice of pine into two 1X4s... but as a former Cabinet maker,. I know how to use it to make rabit,. lap, box, and finger joints,.. dados, mitres,. and tenons, or cut a perfect circle,. etc. The more you use and learn the more tricks you can try.

When I first got my 10D,. I used "P" mode almost exclusively,.. just like ripping a 1X8... :)

The more I know about that Camera,. the more I find situations where it is better to set something myself than it is to let the Camera do it automatically.

[daveh]

Strange question. I've never thought of DOF as a math question. Sure you can calculate DOF but with a DSLR you can just push the stop down button and look too. Calculations can be handy with non-SLRs so you have an idea of what you're going to get. It's also interesting to understand for example how a Minox gets most of the world in its DOF with just an f3.5 aperture.

A few days ago someone asked how those tiny P&S cameras can have such tiny lenses and still be fast. The answer can be shown precisely with mathematics or you can just say something like tiny imagers need tiny optics. Both the rule of thumb and the math have their place.

By the way I own several slide rules dedicated to photography. They date from the bad old days before meters, flash meters and camera automation. These days you can let a machine do all that stuff. Still, understanding what's going on can be helpful and/or interesting.

As for needing to know math to program, it depends on what you're doing and how good you need to be. Most of the top speech recognition designers know a heck of a lot about math. In other fields much less to no math is needed although I do notice that programmers who know a lot of math seem to make better architects.

[Spinners]

Its not that i hate math.. just wanted to see how many of you really use that stuff i read about on a daily basis..

thanks for your input guys!

[RichardtheSane]

I only really have to do any calculations when trying to work out hyperfocal distance on a given lens.
:)

[Morden]

The only serious math I have to contend with is the advanced calculus required to deduce how I can afford another 'L' lens. :)

[hmhm]

Mathematics in photography and software development are similar in this respect. The math that you use on a daily basis quickly becomes second nature, and ceases to "feel" like math any more.

You're not performing complex calculations 100 times a day, but you certainly need to know what a "stop" means, and the relationship between aperture, shutter speed, and ISO.

You don't need to memorize the formula for depth of field and perform calculations every day, but you do need to understand what parameters increase depth of field and what decrease it, and at what rate (linearly or exponentially). You need to know what knobs to twist to get your intended effect, how focal length, aperture, subject distance, "format", and enlargement impact depth of field.

Your understanding of these effects can come from "wisdom" you pick up somewhere (i.e. "some guy in camera shop once said that..." ), which is usually based in truth, but almost always oversimplification, or you can go to "the source" and work through the math yourself to understand _when_ that rule of thumb is right, and when it isn't.

You can use in-camera metering, but you need to understand how that works and what its limitations are, so you can work around them. The camera will be wrong sometimes, and it won't catch its own mistakes or correct them (or prevent them). You have to know how in-camera metering works, so you'll know when to expect it to be wrong, and you have to know what to do when that happens.

A camera may suggest exposure, but it isn't going to suggest that you change lenses, or that you use a different camera. You have to understand what effect selection of a focal length, aperture, ISO, and format will have on your results.

You have to understand what dynamic range is, how it differs between media, and what to do about it.

[Jorge]

Morden wrote:
The only serious math I have to contend with is the advanced calculus required to deduce how I can afford another 'L' lens. :)

I agree. This is the harder equation to solve.

I don't think math is much needed, but you need knowledge to use it - you need to know the features of your equipment and the basic optical rules to take advanges of them. My way is simply to practice, try a setting and see where it takes you - digital is just great for this method!

[rdenney]

Math is a tool. It helps you to quantify an effect that you are trying to achieve, no more and no less. You can also achieve that effect through trial and error, but in the pre-digital (and even pre-minilab!) days when the math-based methods were developed, that was expensive and inconvenient.

Thus, old photographers learned the math to the point where it became second nature to them, to be applied only to the extent needed to solve the problem at hand. Ansel Adams determined the exposure of Moonrise over Hernandez because he remembered the luminance of the Moon, and could calculate the exposure based on that tidbit. He had seconds to make the image and the meter was misplaced--only his knowledge of the math saved him.

I'm as comfortable using the zone system and a hand-held spotmeter in large-format work as using P on my EOS. Both are tools to achieve an end, and it's the end that's important. As someone else said, if you need selective focus to isolate a subject, you need a wide aperture. If you need a fast shutter speed to freeze action, then you won't worry that getting it will cost you in terms of depth of field. If your landscape image needs a sharp foreground and background, then you need to know how to calculate depth of field, because you won't be able to tell if it's in focus on the 10D viewfinder while stopped down. Even in P, I will often turn the control wheel so that I get a combination of aperture and shutter speed that will get the desired effect, and I'm still completely depending on the electronics of the camera to meter the image and set the exposure.

Thus, I would say that there's no need to learn the math until you find yourself unable to achieve the effect you want. The more you understand, the less you'll be at the mercy of Canon's software programmer, but fortunately, Canon has very good software programmers, and there's time. They'll take care of you as learn for most images. But while you are learning, pay attention to those numbers at the bottom of the viewfinder, and try to justify why they are what they are. You'll learn quicker.

Rick "an engineer who uses math only when needed" Denney

[PaulB]

Is photography an art or a science?

[soumya63]

unstuck wrote:

what math did you use to get that particular exposure? and where would P have gone wrong (usually)?

The Depth of field of a 35mm format is not applicable in 10D. So any DOF marking on your L lens barrel will not help you to find hyper focal distance. You need math to compute it.

Canon's Evaluative meter can not determine the proper exposure of a scene like this. Try to capture setting sun in P mode and see what you get in the shadow area like the surf crashing on the boulders. You need to spend some time in spot metering and noting down various reading and then using your judgment and experience to get the correct exposure.

But you may say what the heck, I will bracket 20 shots with 1/3 increment as i am not buying the film. Well that’s the difference between a trial and error and an informed approach. By the way, setting sun will not wait for any trial and error photographer to snap 20 shots at 1/3 bracket interval. The intensity of the sunlight changes every second at sunrise and sunset.


Soumya Mitra

www.mitraphoto.com

P.S. Actually you guys are correct. For amateurish effort, all one need is a digital camera and a big CF. Nothing else perhaps matters.

[soumya63]

PaulB wrote:
Is photography an art or a science?

A combination of both. Without that high tech toy, how could you possibly create your art?

To get a flavour of science part, I would suggest read some articles on color management. Even as an enduser, you will see how much technical hassel you have to bear just to print your art on a piece of paper.

Soumya Mitra

www.mitraphoto.com

[rdenney]

PaulB wrote:
Is photography an art or a science?

Yes.

Rick "who can't violate science and still serve art" Denney

[Jorge]

PaulB wrote:
Is photography an art or a science?

Is science an art? Is art scientific? :D

[Morden]

Is science an art? Is art scientific? :D
Is art artistic? Is science scientific?

This could get way too deep / silly. :)