If you are demoing a decent amp or pedal or guitar, and use a damn mic! You can't make even the nicest of amps will not sound good with a shitty phone recording or a shitty point and shoot camera with the mic on there. Period.
Mic'ing an amp is not hard to do, nor is it necessarily expensive.
"So Trashed why use a mic?"
Here are just a couple of reasons. Hearing the noise from you banging your strings blended with the noise from the amp is flat nauseating. Also, you pick up room noises from some (the real idiots) that have a TV on in the background or their mom yelling out of them telling them to get out of their basement (an unforgivable sin in my opinion). Do you have no pride in your craft? Also if you are recording, the STANDARD is the mic'd tone, that is what you hear on most recordings (especially small time), so don't you want to sound 'professional'?
Why record your amp without a proper mic? There are VERY few decent reasons. NONE of which I can think of at the moment.
Also, it is NOT nearly EXPENSIVE as people think. Even an outdated computer can reasonably hold it's own to a few tracks. $80 on an SM-57, a $100 interface, free DAW (Audacity), at a minimum headphones, and let it rip. The quality is immensely better than whatever you are using.
Video is a different animal, not nearly expensive as it seems as well, especially with how good some cell phones can record video (my cell will record in HD and do well).
The biggest factor is lighting. You may need to spend a few buck on that. The cheap-ass way? take some umbrellas, spray the inside with a metallic paint, and shine a desk light in and arrange them to light the room.
So don't be an idiot, don't be lazy, do it right.
Here is what I use (and I am fairly new to it to be honest). I use SM57 for a mic for the most part, I use a Focusirte Scarlet 2i4 for an interface, Reaper for a DAW, and some higher end Sennheiser headphones and some KRK rockitt 6" monitors (they are my weak point at the moment, but i got them cheap). For Video I use a Nikon DSLR (1080p) and a Rode Video Mic for speaking parts. I use Adobe Premier Elements and go from there. It works great, I will be posting more videos in the near future when i have some more time to make them and get more familiar with the rig.
So if you do it, DO IT RIGHT.
That is it for now bitches.