Working for/with an experienced pro shooter is a really good way to learn. Finding one that will 'take you on' can be hard to do. There are plenty of other people in your position.
There are many people out there, thats a fact... but it is easy to set yourself apart and almost assure yourself a spot.
To the OP here is what I believe it takes:
1. Have a STRONG understanding of the basics of photography. A wedding photograoher is not there to teach you about metering modes. If you cannot talk about aperture, ISO, shutter speeds, the Zone System and have not mastered your own camera at the advanced levels... don't think to waste the time of the professional. They are there to show you wedding photography... not where the ON switch on your camera is. There are some things that I know more about than my mentor... but HE is the teacher and I am the student... in all things.
2. Have a STRONG understanding of the basics of lighting. That means off
and on camera lighting.
3. No emailing, fax or phone calling BS... if you want to mentor with someone, you go see them FACE TO FACE.
4. Be ready to show a strong portfolio of your work. It doesn't have to be hundreds of shots... I used my top 25 in different areas, and knew how to tie each one of them in with wedding photography concepts.
5. Be ready to be THE MOST enthusiastic and passionate person from the crowd.
6. Be a sponge, not a leech! That means to be ready to show that pro what YOU can do for THEM. If that means you lugging around bags of heavy equipment and running around with a light stand for days on end... thats the price. No complaining allowed, and always in a humble spirit of learning.
7. Be ready to work hard... for free. if they see how hard you can work for them, they will be ready to compensate you, if they are sincere and honest.
8. Be ready to sacrifice... that means some may one day ask you to take shots, but anything you shoot belongs to them... thats fine and I see that as part of the price for the free education.
9. Personality. If you don't have it, no one will take you. Be friendly, receptive, customer friendly and know that it takes WAY MORE to being a good wedding photographer than being able to press the shutter. If you are an asset to them, you climb the ladder MUCH faster than if all you can do is hold a light stand really well.
So... does this work? Well it worked for me, not once... but twice! First time I did 4 weddings and 2nd time I did many more (likely 10-20 events this summer alone!), and now, this second time has evolved into me moving from a baggage carrier, to a voice operated light stand, to a part time 2nd shooter to a full time 2nd shooter and by next summer to a full time photographer shooting weddings on my own, and I am not yet done... my plans, if things work out, is to help them take their business to the next level. If he benefits, so do I!
It is easy to write about this, but there is a HUGE commitment to doing things once and doing them right. never take short cuts, and using this outline, you learn the most in the least amount of time.
Which brings me to the final part... do not just choose ANY photographer... do your home work! I looked for some of the most AWESOME wedding photographers in my area, and these are the ones that I approached. Nothing BUT the best for me, right?
If the pro is a weak photographer... YOU will be a weak photographer!
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Shooting a wedding as a newbie... all I will say is this:
There is NO MORE DEMANDING form of photography than a wedding. In no other venue are you challenged to take shots indoors, outdoors, in bright places, in dark places, is slow moving and running fast dymanic places in ONE DAY. The equipment demands are extreme, the skills demanded are extreme.
If you do not know how, don't do it. Do a search, there are a couple of nice threads here on it and one thread in particular about how a couple of youngsters completely BOTCHED a wedding day. If you screw up... the bride and groom lose the chance to preserve a moment in their lives that is NEVER going to happen again... no second chances here!!
Then there are the two situations that I am keeping tabs on... where the brides are suing the photographers. One is totally unwarranted (the man is a consumate pro of many years and has INCREDIBLE pictures), and the second one is a newbie story gone bad.
Last update, the newbie has spent $9,000 so far in lawyer fees, and its not looking good for him. I figure he will be out a good 50-60 Gs before the bride and his own lawyer are done with him.