Here is Part 2 of Basic Digital SLR, where I look at choice of brand and body.

• Part 1 -- Style: Compact digicam vs DSLR
• Brand and body choices
• Lens options, and why I picked what I own
  • Canon EF 35mm f/2.0
  • Canon EF-S 17-85mm f/4-5.6 IS USM
  • Tamron 75-300mm  f/4-5.6 LD
  • others I'm interested in
• Shooting pics
• Development workflow
• High Dynamic Range imaging, or what to do when it's very bright and dark in one image.

Brand:  The big players for the pro-sumer DSLR market are really Canon and Nikon. Other choices are Pentax, Olympus, Sony and Fujifilm. This choice was easy. I've got 5 co-workers with Canon DSLR's, various models.  They like 'em. They can help me with the ins and outs of Canon, and we can sometimes share lenses and accessories (thanks Kevin!). If you don't have a brand loyalty, go for whichever brand offers a model with the features you want.

Body/Model: In a DSLR, you usually purchase the body and then lenses to go with it.  You can also get a "kit" lens, or a body and lens together as a package.  Usually the kit lenses aren't that great.  Once exception is the EF-S 17-85mm f/4-5.6 IS USM.  More on that later.

Canon offers a wide line of DSLR's in their EOS line, from the entry level EOS 300D, through the 30D, 5D, and up to the awesome pro 1Ds mk II.  What are the differences?  Too many to list here.  I settled on the EOS 400D, also called the Rebel XTi.  Why?  Better features than the 250D and 300D, for very nearly the same price.  The next step up to a 20D or 30D was too expensive, and I didn't really need the features of those models.

What do I like about the EOS 400D/Rebel XTi?

• Size -- It's a bit smaller and the lightest EOS model.  Makes it not so bad when carrying around.
• Continuous shooting -- it can take 3 shots/sec for 27 JPEG or 10 RAW images.
• Dust-removal system and anti-dust materials in the body.
• LCD displays camera settings, and turns off automatically when you hold it up to take a pic
• 10 megapixel image. That had better be enough pixels.
• Histogram display on the LCD after shooting helps you adjust your exposure.

What don't I like about it?

• Size -- (heh).  The grip size is a bit small for my hands, so my hand cramps when holding the camera for extended periods.  Being a lighter body, larger lenses tend to overbalance it.
• Auto white-balance under incandescent light is poor.  I'm always adjusting indoor shots by hand. See workflow discussion, later.
• The optical viewfinder seems a bit small. I like the one on Kevin's (30D?) better.

Would I get it again?  Sure...it makes shots like this worth it:

Next article: Lenses!

This is part I of a multi-part article on digital SLR photography.  There are many resources out there on the web...but here are my thoughts.  I'll be looking at:

• Style: Compact digicam vs DSLR
• Brand and body choices
• Lens options, and why I picked what I own
  • Canon EF 35mm f/2.0
  • Canon EF-S 17-85mm f/4-5.6 IS USM
  • Tamron 75-300mm  f/4-5.6 LD
  • others I'm interested in
• Shooting pics
• Development workflow
• High Dynamic Range imaging, or what to do when it's very bright and dark in one image.

So first, there's the choice of compact digicam vs a DSLR.  I've got a compact camera, it's great. My little SD400 fits in a pocket and takes great shots.  If that's all you want out of a camera, stop now. Find a small digital camera like the SD400 and buy it. Our went to London with us, and I would take it again.  I don't want to lug a large DSLR around the UK...we had enough with lugging our bags through the underground.

Uh, so what's a DSLR?  A digital single lens reflex is like your dad's 35 mm film camera, with an image sensor instead of film.  You can put any different lenses on the front.  The camera body itself just has the sensor, electronics, viewfinder, and battery.  When you look through the viewfinder, you're seeing the scene exactly through the lens, as the imaging sensor is going to see it.

So why a DSLR? Easy--two things: Image quality and control.

A compact camera has a small lens, which means less light gets to the sensor.  So pics in darker settings will be blurry, or require a flash.  With a DSLR you can use a lens with a small f-stop (lets in more light).

This is at the core of a compact digital camera (1/2" across):

Telephoto , originally uploaded by jurvetson .

The zoom range of a compact camera is also limited.  And if you want to zoom in (or out) more than the built-in lens allows, you are out of luck.  Sure, sometimes you can screw on those add-on lenses, but they aren't usually worth it.

Control--that means you can set nearly all aspects of image acquisition.

You can set shutter speed from seconds (minutes, even) to 1/4000 of a second.  Faster shutter speeds help to freeze action.

You can set the aperture--that's how much light the lens lets in. Large apertures allow for quicker shutter speeds.  They also tend to have a very shallow depth of field. Smaller apertures let more be in focus, but require more light.

ISO is another thing you can adjust. Just like old fasioned film has different sensitivities, so can a DSL sensor.  High ISO film (like 400 and 800 on up) have larger grains.  They can image with less light, but at the cost of a grainier image.  Lower ISO film, such as 100 and 200, work better in bright light.  They give you a nice clean image.  DSLR ISO is very similar.  The natural grain of film is replaced by the not-quite-as-nice look of multi-color noise.  Different cameras handle this differently, but it can still look ok.

The balance of those three options, shutter speed, aperture, and film ISO are in tension with each other.  Move one, and you have to adjust the other.  That's why many DSLRs offer priority modes.  So if you are shooting in aperture priority mode the camera will adjust shutter speed to get the shot at the aperture you set.  The converse is true for shutter priority.  Of course you can put it on full auto and shoot away, but then you're missing most of the fun and creativity of a DSLR.

Of course those three options are also going to interact with our choice of lens, but we'll get to that in part 3.

Stay tuned for Part 2 -- Choice of brand and body.

Canon Rebel XTi photo by