equipment recommendation - How do I choose a camera bag?

What considerations should I factor in when choosing a camera bag of a given style, and how important is each one?

_{For a question on the different bag styles, see: What different styles of camera bags exist, and how are they different?.}

As an example list of bag qualities to get things started:

• 
  

  Size--both in terms of what it can hold and what it's like to carry.

  
  
  


• 
  

  Features--such as weather/rain protection, amount of padding, ease of access, places for accessories, etc.

  
  


• 
  

  Prices/brands--are some brands that much better so as to justify the sometimes large price differences?

  
  


• 
  

  Where to buy--online (direct or from a reseller) or in a brick-and-mortar store?

  
  

Answer

Once you have your style chosen, then the first thing is to find the right size for you given the circumstances in which you expect to use that bag.

Size with camera bags is kind of abstract since equal volume bags may not be able to fit the same equipment due to their shape. The only way I found of solving this is going to a photo store with ALL the biggest gear I intend to carry at once and try to fit it. Yes, sometimes it take over an hour to try all the models which look about the right size.

There is no reason to get a back without rain protection unless you plan never to be out in the rain with your gear. Otherwise, you'd need an extra bag just for rainy days? And what if the forecast is wrong? Or you happen to walk somewhere where it is customary to throw water-balloons at strangers on that day! (This did happen to some friends of mine)

Brands have different styles based on their intended audience. A corollary to the first rule is only to buy brands available in local stores. Between those your preference will dictate: Do you prefer a plain looking one or a flashy one? Do you prefer to pay more for one that is durable? Do the zippers on one brand annoy you? etc.