Hello....new to this site and hoping someone can help. I had a Nikon D3100 that I used for a lot of interior portrait photography. I had it setup with a Cactus V4 remote flash trigger, mounted on the hot shoe, and remote flash receivers on 2 external flashes. This worked great. The camera would trigger the remote flashes and I wouldn't have to use the onboard flash. Well I couldn't resist the massive increase in megapixels of the D5300 so I "upgraded" to one recently. Now I'm wondering if that was a mistake. I tried setting this camera up the same way I had the other one setup with the Cactus trigger/receivers. With the Cactus trigger mounted on the hot shoe, it wouldn't trigger the external flashes with the onboard flash turned off. I turned the onboard flash on, and when the flash pops up it would hit the Cactus trigger unit that was mounted on the hot shoe. I took the trigger off the hot shoe, and the camera would still trigger the remote flashes as long as the onboard flash was on and being used. Problem is, the onboard flash really screwed up the pictures when it was used along with the remote flashes. Terrible shadows no matter where I moved the remote flashes. Even tried to reduce the intensity of the flash and it didn't help much.
So, what I need help with is how do I use remote lights without using the onboard flash? Is there a way to turn off the onboard flash, and still trigger the remote flash lights? I'm really confused how this would work on the inferior D3100, and why it won't on a camera that is considered to be an upgrade. Please help! Very frustrated!
Thank you!