Things I've learned about photography

Thursday 28 June 2007

Since working at Tabblo, I've been trying to learn more about photography, and bought myself a nice camera (a Nikon D50 digital SLR) and a couple of lenses. My brother has been a big help.

I realized that my growing understanding of photography can be captured in a series of facts and guidelines:

  • Hold the camera as still as you can.
  • Take lots of photos.
  • Throw away photos you don't like.
  • Get closer to your subject.
  • The subject doesn't have to be in the center of the frame.
  • The slower the shutter, the blurrier the image will be.
  • The lower the aperture number, the wider the actual aperture (the opening in the lens that lets in the light).
  • The wider the aperture, the more light gets in, so the faster your shutter can be to get the same exposure.
  • The wider the aperture, the shallower the depth-of-field, so the background will be blurry.
  • A lens with a wider maximum aperture is called "faster" because it lets you use a faster shutter.
  • The higher the ISO number, the more sensitive the sensor, but the more noise in the image.
  • A lens will be sharpest in the middle of its aperture range.
  • Back-lit subjects are really hard, but different metering modes can help.
  • Shooting in RAW gives you more flexibility in post-processing, but gives you the largest files.
  • Filters do magical things that I don't understand yet.

I'm not sure I can encapsulate my understanding of other fields aphoristically like this. It would be interesting to try.

tagged: » 12 reactions

Comments

[gravatar]
Dave Delay 9:03 AM on 28 Jun 2007

This is a great list, Ned. I would only add one guideline somewhere near the top: "Use exposure bracketing." In other words, assuming you are using auto mode, you want to make multiple captures of the same scene at slightly different Exposure Values (EV). When you load the images to your computer, you can pick the images that look best. Exposure bracketing takes a lot of the guess work away.

[gravatar]
andrew 9:51 AM on 28 Jun 2007

Filters do indeed to magical things. I used to be quite a photobuff 20+ years ago (in the days of film yore). I saw a guy who used a very VERY dark neutral density filter to take a picture of Time Square. The filter was so dark that the exposure took several hours. That might not sound so cool, except the resulting image was cool. None of the cars were in the photo long enough to register on the film, so the resulting picture was a completely abandoned Time Square in the middle of the day. Special FX without a computer!

And let's not forget esoteric terms like "reciprocity failure" which, I believe, is still an issue in the digital age...

[gravatar]
Julien 12:07 PM on 28 Jun 2007

How about:

"The camera does not take good or bad pictures. The photographer does."

[gravatar]
Sean 12:35 PM on 28 Jun 2007

Ned,

You should check out the Nikon forums at dpreview.com and the articles on the Digital Photography School blog. I've found them to be very helpful as I've learned about photography and about my camera (Nikon D80).

I highly recommend Understanding Exposure, by Brian Peterson. It completely changed the way I take pictures.

Sean

[gravatar]
Val 3:21 PM on 28 Jun 2007

Ned,
Great to see your growth here! Here are a couple of the most useful things I know about photography, and they help especially with the problem that "Back-lit subjects are really hard...":

1) Use the exposure lock feature on your Nikon. That is, point the center of the lens at an area of the subject you want correctly exposed, such that the camera doesn't see differently-lit areas. With a backlit subject, this means pointing the camera down until its frame is dominated by the shadow part of the subject, and there's very little bright sky in the frame.

Now, adjust the exposure as you like -- manually manipulate shutter or aperture, or just let the auto mode do its thing. When you see the settings the camera wants to use to expose the shadow area, press and hold the exposure lock button with your thumb and re-frame the photo to include the bright background. Note that as you're reframing, the exposure controls are no longer changing -- they're locked to the sample you gave them. Think of it as "exposure-by-example".

Once you're OK with the composition, (still holding EL) click the shutter release. Now you get the composition you wanted, but the camera is still exposing based on a dark shadowy subject instead of a bright subject (the sky).

Hmmm, now that I read that, it sounds much more complicated than it actually is. Let us know if you get this or we should make a less-clumsy attempt to explain.

2) Unless you're going for a silhouette effect or have no other choice, try to avoid backlit subjects. Ideally, the light source is to your side or behind you. Side lighting produces interesting light and shadow on the subject. Light from behind you lights the subject well, but can flatten the image by eliminating shadows, and can cause the subject to do unpleasant things, like squint (if it has eyes).

[gravatar]
Gheorghe Milas 11:14 AM on 29 Jun 2007

- on the back-lit subjects you might also try to use flash (expose for the background and lit the foreground with flash)
- you have to test a lens to tell what aperture is sharpest but buy a good lens and use an aperture of F4 to F8 while apertures like F2.8 and F16 can be softer which does not mean a bad picture (sample)

[gravatar]
Gheorghe Milas 11:29 AM on 29 Jun 2007

About what Val said at number 1, alternatively:
- if you wish to take more then one picture or find it hard to hold the lock down then change the camera to manual program and expose on the part of the picture you want correctly exposed and then recompose for the actual picture and shoot, the setting are now good for the part you what good.
- use spot metering for example to expose for a person's face.

One tip I find myself very usefull is to change the white balance to something else then to what it would be correct, for example on a sunny day use "cloudy" or better "shade" as white balance

[gravatar]
Julien 1:10 PM on 29 Jun 2007

Gheorghe: "electric light" white balance + flash is awesome at night :)

[gravatar]
Bruce Perry 10:08 AM on 2 Jul 2007

Here's a blog post I made a while back on the subject of learning about photography.

http://petardier.livejournal.com/86772.html#cutid1

My advice was less technical, so you've given me some interesting food for thought.

[gravatar]
Doug Napoleone 9:43 PM on 4 Jul 2007

Ned,

Thanks for the pointers and links! I used the information to take some 3-10 second night exposures while camping over the past week. Hope to have the images up soon.

[gravatar]
Doug Napoleone 11:34 PM on 5 Jul 2007

Here is a tabblo of some of the more interesting shutter speed, ISO, and aperture settings.

A Quiet Night at Wells

[gravatar]
Tony E 10:51 AM on 7 Jul 2007

Here is some info I shared with a coworker about basics and taking sports pictures...

Here is all the info you need in an awesome website (see the tutorials section, but you can start with the camera-lenses section since that is what we were talking about the other day...)
http://www.cambridgeincolour.com/tutorials/camera-lenses.htm

Also these Nikon Digitutor is nice and simple:
http://www.nikondigitutor.com/index_eng.html


Easiest way to understand the basics is imagining that for any given picture you need to fill a cup of water to the brim in order to expose it correctly,

To achieve this, you have in control 4 parameters:

1) the width of the hose (F-stop number of the lense, lower number, wider opening...),
2) the amount of time the hose valve is on/off (shutter speed),
3) the width of the cup brim (ISO) so as to collect as much water as possible, but beware that the wider the cup, the more pollution it collects too (the higher the ISO, the more noise is introduced from sensor amplifier distorsion )

and a parameter that you may or may not have control of is,
4) force/pressure of the water coming out of the hose (amount of available light, day, night, flash, etc)...


For sports freeze action, you can only open/close the hose valve for say example 1/300th of a second,
so it better be a WIDE hose (F1.4, or F2.8...) to fill that cup, and the cup brim also be as wide as possible to collect all the water, but not so wide where you collect lots of pollution....

all these settings are relative to how much pressure the water comes out with of course ( day pictures (high pressure) vs night pictures (low pressure) )

As a general rule, setting the camera in aperture mode, and selecting the lowest aperture possible (widest hose opening), will automatically give you the fastest possible shutter speed given the amount of available light.
Use a monopod or tripod will make a big difference too.
If the action is still not freezing enough, just keep bumping the ISO up because you have reached the limit of the lense...

Another trick is to zoom out a little, which will allow the lense to open a litter wider (lower f-stop) plus will also have a little bit more overall light to collect (bigger image area reflects more light into the camera),
then just zoom in the picture in the computer and crop it (since we don't need 10mpixel images for screen viewing....) But this will not be good if you print the image on 8.5x11 for example....

Add a comment:

name
email
Ignore this:
not displayed and no spam.
Leave this empty:
www
not searched.
 
Name and either email or www are required.
Don't put anything here:
Leave this empty:
URLs auto-link and some tags are allowed: <a><b><i><p><br><pre>.