Ikelite housing - TTL converter options - non-Ike strobes

I am picking up a Ikelite housing for my 20D, in part due to the price and also due to the limited support from housing mfgrs for this body (and Subal is just too $$) I would love to upgrade to a 40D, but its just not feasible at this point...and no housing support doesn't help that.

I don't think I like the Ikelite strobes, they are just so bulky...and I can get 2 YS-110s for barely more than a single DS-125. My LDS also heavily pushes towards the Sea&Sea. I also like the option of being able to carry standard spare batteries, call me paranoid...but cold water and batteries don't mix for long life, so having the ability to swap them quickly in a surface interval is key. I already have a variety of AAs for dive lights and surface flash gear, so no reason to invest in yet another family of batteries and chargers.

With that said, I wanted to check the options for using non-Ike TTL strobes. The 20D housing has integrated TTL and I see that Ikelite has sync cords for the system to connect to S&S but it is "manual only". Is is that they don't "support" TTL with other strobes, or that it really doesn't work? If the later is the case, how tough is it to put someone else's TTL converter on there. The dive shop called the company they send UW photo gear to for servicing, they said that a S&S TTL converter could be put on the Ike 20D housing. Even with buying a TTL converter, it likely comes out cheaper than DS-125s.

I will be primarily shooting macro, as my waters don't favor wide angle. I will either being using a 60mm or 100mm macro lens. Should I just not worry about TTL and deal with manually adjusting the 2 strobes?

I feel like a fool all over again. I grew up with SLRs above the shimmer, but the gear for dunking is all different and proprietary. Thankfully the SLR isn't, I can mix flash brands, lens brands, and filter brands. Imagine the uproar if you had to buy only Canon lens, flash, filters, and compact flash just because you had a Canon body. Too bad the UW housing companies don't work on a standard. I would think there would be more money to be made by simplified production and quantity than closed systems with lower sales #s, and just chasing higher/protected margins.

Thanks in advance!

I hadn't ever looked at Inon strobes before, but it seems like there are a lot of Inon fans on here. I just checked out their web site and it seems they have an interesting offering. I am guessing that their "external auto" uses a built in light meter to accomplish what TTL would, it determines how much light is hitting the subject and controlling light output accordingly?

How well does their "external auto" work? It appears the Ikelite sync cord is the same for Sea&Sea and Inon. So is the "external auto" a valid replacement for TTL?

From what I understand and have read and been told, you can not use TTL with an Ike housing connected to Sea&Sea strobes. I have been wondering that myself lately as well. I just purchased the Ike housing for my 20D with dual YS-250's. I was looking at the 110's but I tend to like spendming money. It would be nice if Sea&Sea had a housing for the 20D but unfortunatly they dont. If you here anything about it being possile to use a TTL converter for an Ike huosing and Sea&Sea strobes shoot me over an email. I would be interested in knowing more about it as well. Mahalo

I think I am just going to go with the Ike strobes. Someone on here was using the Ikelite strobe as a master and then using optical-sync with the YS-110, that may be another option. The YS-110 is supposed to support TTL via optical, so essentially you'd be using an Ike strobe as a TTL converter for the Sea&Sea. If this worked well, you could just use a Ikelite DS51 and black out the front with a dark diffuser, than just use Sea&Sea's dual optical sync cord to 2 YS110.

Hard to say if it would work without trying, I'm going to see if I can test it in the LDS' pool. If the YS110 is as bright as the DS125 then it would be a "bargain" route to more light, cheaper than any other TTL converter options for sure. Or, if I can get my LDS to bargain with me I may just go ahead and get 2x DS125.

It seems the largest weakness of the YS110 is the recharge lag, so while you gain the ability to take shots quickly with a DSLR the YS110 becomes the bottle neck, slower than most P&S cameras it seems.