Why is it that the picture in the capture panel sometimes shows and sometimes doesn't? I have captured film from a VHS-recorder/player through firewire for many years now. I don't recall there was any problem initially and I can't recall when the problem arose. I have recently started capture 8mm film from a scanner also by the aid of firewire and both machines are connected to the same card in my computer with separate cables and with separate entrances to the card. I have tried different sequences when starting up like PP first and tape player or scanner thereafter or reversed. The problem arises at start-up, that is, if I get a picture from the tape player or the scanner it stays as long as the system is running. Once when I couldn't get a picture from the scanner I put a tape in the VHS-player and tie picture showed up. Then I changed to the scanner input and got a picture from that as well but that may have been just an coincidence becaus I have not been able to reproduce that workflow. Although the picture doesn't show up the capture function works all right and the clip turns up in the project panel. I can see what I capture by watching a monitor beside my computer screen but is not an ideal way for me to work.
I haven't changed any basic setups and drivers are updated.
Haven't done a great deal of capturing in premiere, but have done a few large jobs in the last few months and doing one now. Never seen this behavior. Please tell us your system specs: OS version, Premiere version, amount of RAM, Hardware specs including graphics card and whatever card you're referring to.