This maybe in the wrong forum, but it is realted to mainly sports photos.
I know this maybe a silly question but I have to ask. When you are shooting at night at a HS football game, does having a lens hood on your lens effect that amount of light that is getting to the sensor. Can you gain a stop or two?
I ask this becuase recently I was at a game and I saw a couple of shooters without hoods on their 70-200 and 300mm 2.8.
I would think it's more likely to cause lens flare from the lights than more light to the sensor. But as Widgic said it should be easy to try, just remember the glass is more exposed to potential damage.
You don't care about how much light is getting in through your lens (well ultimately you do but you care about the source). All that matters is how much light is hitting your subject. Taking a hood off won't affect how well lit a basketball player is 50 feet away. Light travels linearly so taking a hood off might allow light to come in from an angle but any light reflected from your subject is already coming in regardless of a hood.
For instance if there was a bright light source out of frame but within your angle of incidence when your hood was off, your metering would be fooled and you would have a bad exposure (underexposed at the subject). You gain a stop or two of light as you asked but not where you need it. Make sense?
