So I am already using sonar live as a soft synth host on a laptop.  Looking to add projection backdrop with projector.  Anyone using sonar somehow to sync backing or midi to intro videos or other special effect videos? found a few inexpensive video apps that might work. just wondering what anyone was using. gonna project behind the drummers

Google a group called Kicksville. They use Sonar for backing tracks, and all their MIDI control of lighting and onstage effects.

You will need a projector but Sonar will do just fine for video playback 

John
You will need a projector but Sonar will do just fine for video playback 

Not for this purpose I don't think. If OP just wanted to stream a single vid from the Video View then perhaps but that would require a manual action anyway and there are much better video players that could be used for that type of action.
 
What I think OP wants is MIDI triggering of specific vids (and lights) at specific points. That can of course be done FROM Sonar PRV or any of the other MIDI options but would require another program for the vids that can accept MIDI signals to activate specific vid playback. Same goes for lighting rigs that accept MIDI.
 
Essentially the vid program and lighting program act as "virtual instruments" except instead of triggering sounds/samples they trigger videos and lights... and I guess in the case of video and hardware units designed specifically for this type of thing it would be more like having MIDI playback in Sonar controlling an external hardware synth.
 
So... yeah, since Sonar can of course be used to program and playback MIDI you just have to get those live signals out to whatever vid/lighting hardware you intend to use.
 
I have seen quite a few vids on this topic using Ableton (which seems much better suited/designed for these things) but the principle is the same.
 
Check out youtube for "Ableton Live Light Show Gear Control" and any other buzzwords on the topic and you'll find those vids.
 
Then you can translate that knowledge to what Sonar MIDI can do. It's the same stuff really just maybe not as  "Baked In" or well documented as the Ableton methods.
 
Lighting gear these days will generally have some kind of MIDI control options. I think it's the video aspect that might take some doing.
 
That is of course if you actually want music based vid triggering and/or interactive vid triggering by band members on stage.
 
Just gitting play and having something play in the background from a projector ain't no thing. You just hook up the projector... press play on the vid software (could be WMP or anything really) and that's that. Sounds like you want something more interactive though.
 
Cheers.

OK Sonar can load events from triggers within a MIDI track. 
 
See below
MCIcmd events
Media Control Interface (MCI) commands are special events that let you control other multimedia hardware and
software (e.g., CD-ROM drives, laserdiscs, sound cards, animations, video) during playback. MCI commands are
part of the multimedia extensions in Windows. MCIcmd events have one parameter—the command line text of the
MCI command. Here are some examples:

Look on page 916 of the manual for more information. 

John
OK Sonar can load events from triggers within a MIDI track. 
 
See below
MCIcmd events
Media Control Interface (MCI) commands are special events that let you control other multimedia hardware and
software (e.g., CD-ROM drives, laserdiscs, sound cards, animations, video) during playback. MCI commands are
part of the multimedia extensions in Windows. MCIcmd events have one parameter—the command line text of the
MCI command. Here are some examples:

Look on page 916 of the manual for more information. 

Totally and I of course don't fully understand all that stuff but just wanted to point out Sonar can't be the video player for complex video sequences/triggering. It just doesn't allow multiple vids to be loaded in a single project which of course would not be desirable in this scenario.
 
I've also noticed a bit of glitching in the Video View thingie too that wouldn't be great being projected live.
 
Sonar is of course not a video program and not designed as such so that's not a problem or complaint... just reality.
 
For MIDI though it's full featured so would/should totally integrate with other hardware/programs designed to accept the signals.
 
Cheers (and sorry for being a pedant).
 
;-)

On a VJ forum, I read about VJamm (www.vjamm.com) and Arkaos (www.arkaos.net).  I don't have first-hand experience doing this, so let us know how it works out.

All great thoughts and directions in this thread thanks a lot.  If something in sonar like midi triggering VLC  or some other other video player even with MCI or something that might be helpful to start.  You know I have used Light Factory and backing tracks and send midi out to control the lights according to the sequence and that does midi triggered video.  That would still work using sonar, I just have to go back to spending all that time sequencing and programming,  is the CLICK track in the in ear monitors still the best way to keep the live synced up with the "prerecorded/preprogrammed" show these days?  I sure love the dynamic jam energy of allowing the band to set there own tempo live but who does that with bigger shows these days I suppose? Looks like a third party video app that takes the midi from the soft synth sonar installation and runs lights and video might be the way to go.   If it was one video, it probably could be done with sonar but I dont think I will head that route.
Thanks.

Did you look up kicksville and get in touch with them? They have been using Sinar to run the backend of their huge live shows for years.

They would surely be able to answer your questions.

They are also on the forum. Look them up and send them a pm.