Hello,
I am just getting back into photography after a 12 year absence. I just purchased a used D850 and a used SB-900 flash. I'm hoping to find out what all options are available to me to remotely trigger the speedlight. I know I can buy an SU-800 speedlight commander. I've also read that you can trigger a speedlight with another speedlight. Does it have to be the same model? I feel like I had a pocket wizard before, but I just can't recall. Are pocket wizards still a possibility?
Thanks in advance
Least expensive way to optically trigger the SB900 off-camera is to use its "SU-4" built in dumb optical trigger mode. In this mode the SB900 will fire when it sees the light from some other flash. Since the D850 does not have a built-in pop up flash you will need to put a stand alone flash in its hot-shoe. This can be an inexpensive thrift store manual flash or something you already may have but you should be aware of
this trigger voltage issue and cameras with electronic flash sync circuits.
The very expensive Nikon SU800 controller is IMO a unwise option because Nikon has abandoned their CLS AWL smart optical wireless system and gone to RF (Radio Frequency) triggering. You can get the superior radio triggering from 3rd party vendors for way less money.
Least expensive way to use radio triggering would be a pair of basic manual radio transceivers like my YongNuo RF-603II units for about $40 US. These are usually sold in pairs with an included remote shutter cord.
You want the "N1" package with the Nikon 10 pin connector . The SB900 will be in manual power mode and you will need to set the power level on the back of the flash.
Pocket Wizard are still around but the lower end of the market is now dominated by the highly affordable Chinese Godox brand radio triggers and their compatible speedlights and studio strobes. I surprised the Godox option hasn't been mentioned yet.
Godox's X1R-N is a receiver you can put under your SB900 giving it remote TTL auto exposure and remote manual power control from one of their receivers like the X2T or XProII for Nikon cameras. However if you are planning on more serious off-camera flash work in the future consider reserving your SB900 for on-camera use and instead of the X1R go with one of the Godox flash units. That's what I have done with my two SB600s. There's lots of options in the Godox universe and the holiday deals on Adorama's Flashpoint rebranded Godox gear was too good to pass up this year.