sorry for being late to the party with a long post, but since I was tagged I figured I should weigh in.
If you are planning to dive to the Andrea Doria, or the SS Tahoe, you may want to train with a manifolded twinset. You will need more gas, of different types than a SM rig will allow.
You can use multiple bottles quite readily in sidemount. 4 bottles is not uncommon at all to kick around in sidemount in the Florida days. It's done every day down there.
This is 6 bottles, not 4 and done for bragging rights more than anything. No one should ever actually dive like that. 4 bottles is not bad at all.
this is collecting empty deco bottles and even in backmount, if you have more than 2 bottles you have to butt mount at least one of them. Completely normal to have a bouquet behind you. This is likely a "look at me" marketing type picture, as there is no way in OW he would be using all of those bottles. If that is an OW dive and all of those bottles are being used, then they would the entire teams say 70ft deco bottle that once depleted would go to a single divers leash. When handed to a support diver, all the 70ft bottles would be empty and together for them to get to the surface. Only other exception would be cleaning up a big cave dive where those stages would be empty *which you should do that dive on a CCR so you don't have to do that*
With the way backmount deco bottles are hung, you are generally more streamlined with 4 bottles in sidemount than you would be with the necks hanging down in backmount. You usually load one on each side though vs. backmount where they all go on the left.
It should be done like this. This applies to sidemount as well for the butt mounted bottles. You should never have more than 2 bottles on one side at a time IMO. As you go deeper, the bottles act more empty than they are since we assume He doesn't weigh anything, so a 30/30 AL80 will act like an EAN32 filled AL80 at 2000psi which means it floats. Air/Nitrox bottles are annoying to butt mount in sidemount when full. If on a scooter, the bottles lay down in the slipstream so it's not bad at all, but again, even in backmount you do the same thing so you don't get any benefit by being in backmount.
to answer the tag from
@Diving Dubai the prereq's for getting a sidemount cert depend on what you're trying to do with it. Are you actually trying to squeeze through restrictions? If so it depends on what depth you are trying to squeeze through for OW, and in a cave it gets a little dicey. Often a cert won't be issued unless you need it for a dive site/boat. If I teach a generic course in sidemount, you don't get a "sidemount cert" because I think it's a waste of money. If you are trying to learn to actually sidemount dive to get through a restriction though, then that usually is a "sidemount cave" card or something because there are real skills there to keep you from offing yourself.
The hardest part of finding a course
@markmud is that many agencies, including PADI allow you to essentially self-certify so there is no guarantee that your course will make you look good.
This is a sidemount instructor....
4 dives is NOT excessive for learning to sidemount dive. There is a lot of gear tweaking that takes time to get right. If you are doing it for the gear configuration, there is no benefit to doing it in OW and doing it in a pool is actually the best way to do it because you have easy access to the shallow water section to stand up and make some fine tuning adjustments. Doing that course off of a boat is downright idiotic. Remember, those sidemount courses are to get you used to a new gear configuration *like the drysuit course*, they are NOT to teach you how to dive sidemount in a place that requires sidemount. People knock the supermanning bottles skill, and while the skill itself is completely useless in most situations, the skill itself is to get you used to clipping and unclipping bottles which is immensely useful when diving off of a boat where you need to be comfortable unclipping them before coming up.
Some of the really good instructors can get you sorted out in just about any gear configuration. Most will not. You will have to travel to find those instructors, that is all but guaranteed.
I think that covers everything...
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