Originally posted by Lord Lucan No doubt he had reasons, but did not really offer them.
I am no longer a pro, and you're right, his 4 ovens analogy didn't make sense. But the main reasons why a pro may need that level vs. a non-pro include:
a) Weather-sealing. As a pro, I'd have to be out in horrible weather from 12-18 hours a day. Yes, I prefer weather sealing even as a non-pro, but as a pro, my livelihood depending on getting the shots without a camera locking up or condensation in the lens.
b) Shutter actuation life expectancy. Back in the film day as a pro, I'd work for agencies that would not accept me not turning in less than 10 rolls of 36-exposure film each day, regardless if there was 360 good shots to take or not. Today, if you shot 'only' 360 digital shots, the client or agency would think you were negligent. Most pros (depending on the subject) can easily shoot 1000 shots per day. So on an entry level camera rated for 100,000 shots, a pro could kill the shutter in 6 months. It's not only a hassle to have a camera go down at work, it's a hassle for tax planning, replacing the down camera, etc.
With entry level cameras, rated at 100,000 shutter life expectancy, you will typically see them fail at less than 100,000. With pro cameras rated at 400,000, you will typically see them exceed that count before failure.
c) Not just FPS, but the buffer for longer continuous bursts. Of course we'd all like to shoot wildlife or sports with longer bursts before the frames per second slows down, but if I'm competing for sales, I'm more likely to succeed and this affects your income.
d) Number, availability, and types of accessories to buy or rent. Also Canon and Nikon pros will get loaners from Canon and Nikon, with the expectation it's compatible with a pro-level camera.
e) This seems totally cosmetic, but there is a perception that a pro must shoot with pro level gear. This expectation comes from models, agents, clients, etc, that are delusioned that because they've always seen a Canon 5D Mark IV or Nikon D5, that you can't possibly be serious showing up with a Pentax K-1 or a 645Z instead of a Hasselblad. When I was a film pro, I struggled with this attitude with my pro-level Minoltas that when they were stolen, I threw in the towel and replaced it with all Nikon gear. The Nikon didn't make me a better photographer, but in everyone's eyes it did. If anyone bothered to compare my Minolta images vs. my Nikon images, they would have seen little or no difference.
I'm sure there are more reasons, but a better comparison would have been a chef outfitting the kitchen with a consumer grade oven you'd find at Sears or Home Depot vs. a pro grade oven intended to be used 7 days a week, 12 hours a day, that if it fails or breaks, shuts down the restaurant affecting many people, not just one family.