If you drive stepping motors with a pair of 90 degrees out of phase sine waves (sine plus cosine) you will often find the motion to be much smoother (I assume you would have 2 phase motors). I suggest selecting motors with finer steps, 200 per revolution or more. I have seen 400 to 500 step, two phase motors in applications like plotters but you will need some luck or patience to find these; however, 200 ought to be good enough.
Bob At 11:57 24.09.02 +0200, you wrote: >David, >I want to make a round shot camera on 120 films. >I got a 28mm lens 42mm mount that should be ok to start with. >I already know how to make the film slide synchronised but I'm still >stuck on the choice of the motor. ( yes I want to use a motor ! ) >First I wanted to use a step motor + gears but I'm afraid about the >lines it could make on the film. >The second choice is a geared DC motor but how will I have an >accurate positioning ? I thought about coupling a 360° pot or using a >perforated disk with sensors kinda like in a mouse. >I'll drive the motor with a microprocessor, PIC or basic stamp. >I prefer the step motor because it's easier for me to drive it. >For now I'm just at the draft drawing point, trying to put all my >ideas on paper but I hope I'll soon have a prototype. >I already made a few draws. The first ones where what I wanted to >have but now I'm drawing something that looks like what I want but >easier to build with the tools I have and the materials I can afford. >I try to make it compact, easy to build, easy to use and not very >expensive. That a tricky exercise ! >I'll also try to include the possibility to switch from 28 mm to 50 >mm if I have time to look for a solution of easy switching gears. > > Regards, >Cedric. > >On Mon, 23 Sep 2002 19:39:21 -0700 (PDT), david hajjab wrote: > >Cedric, > >What type of panoramic camera do you want to make? > >David > > > >__________________________________________________ > >Do you Yahoo!? > >New DSL Internet Access from SBC & Yahoo! > >http://sbc.yahoo.com > >_______________________________________________ > >Cameramakers mailing list > >[EMAIL PROTECTED] > >http://rmp.opusis.com/mailman/listinfo/cameramakers > > >-- >Cedric Malitte, [EMAIL PROTECTED] on 24/09/2002 > > > > >_______________________________________________ >Cameramakers mailing list >[EMAIL PROTECTED] >http://rmp.opusis.com/mailman/listinfo/cameramakers _______________________________________________ Cameramakers mailing list [EMAIL PROTECTED] http://rmp.opusis.com/mailman/listinfo/cameramakers
