Estimating and quoting on work becomes easier with experience. You say the work may only take an hour — really?
Do you have to capture / encode the video, export to a specific format, deliver on any specific media?
In addition to competitive rates and your skill level, these are all costs and times that need to be considered when estimating a job.
Your time on the computer is only one element of the job process. Will there be client approval meetings? Will you upload the files to a server? All these take time — yours. That an your skill is what you are selling.
I tend to quote by the job and avoid quoting an hourly rate.