I am interested in gettingg a Heinrichs Weikamp iTTL converter for my Aquatica D70 housing setup with a couple of SB-105's. The site says these strobes can only be run in Manual TTL. Can somebody explain Manual TTL to me , and how it is different from stricly manual operation? Of course this may be irrelevent because I don't have access to the exposeure compensation button on the Aquatica housing. Thanks.
The Aquatica housing for the Nikon D-70(s) does allow control of Exposure Compensation. M-TTL mode is activated by putting the camera in rear curtain sync mode. The strobe is left in the TTL setting. You control the output of the strobe using your exposure compensation button on the camera, as follows:
0.0 = Full Power
. . .
-0.3 = 5/6 Power
-0.5 = 3/4 Power
-0.7 = 2/3 Power
. . .
-1.0 = 1/2 Power
. . .
-2.0 = 1/4 Power
. . .
-4.0 = 1/16 Power
This can be used in conjunction with the Flash Exposure Compensation button if your housing can access this button. The affect of the two exposure compensation settings is additive. In normal use the Exposure Compensation gives a wide enough range of power.
On most housings you'll need to set the Rear Curtain Sync mode before you install the camera into the housing.
Dave Marsh
Thanks Dave,
This makes alot more sense now. So really this just gives me a way to get more settings out of my 105 strobes. I think the smart money would be to use my YS-90's instead, as that would allow me to get true TTL function.
Yes! With the YS-90's (on the D-70) you'll have both an ITTL and the MTTL features available to you. I'm not personally a fan of TTL mode but if you are then I'd recommend ITTL for macro and MTTL for wide angle. You just have to remember to set Rear Curtain sync mode before you put the camera into the housing when you want to use MTTL mode.