Searching \ for 'trigger a film camera' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/index.htm?key=trigger+film+camera
Search entire site for: 'trigger a film camera'.

Truncated match.
PICList Thread
'trigger a film camera'
1998\11\18@192840 by Ralph Landry

flavicon
face
I'd like to trigger a film camera from a pic.  Also it would be nice
to use a cheap auto wind type but I haven't been able to find any
that have an external switch for this.  I've thought about breaking
into the camera to get at the switch but it's not elegant.  A solenoid
plunger would work if positioned over the button but any I've seen
are really power hogs.  Does anyone have any ideas or tips they'd
like to share on being able to do this?

-Ralph
spam_OUTrlandryTakeThisOuTspamhaywood.main.nc.us
"If they call it Tourist Season why can't we shoot 'em?"
ICQ# 19545315

1998\11\19@115530 by John Payson

flavicon
face
|I'd like to trigger a film camera from a pic.  Also it would be nice
|to use a cheap auto wind type but I haven't been able to find any
|that have an external switch for this.  I've thought about breaking
|into the camera to get at the switch but it's not elegant.  A solenoid
|plunger would work if positioned over the button but any I've seen
|are really power hogs.  Does anyone have any ideas or tips they'd
|like to share on being able to do this?

You probably will need to use an auto-wind camera since
even cameras with electronic exposure control frequently
use a 90% manual mechanism:

There are two sliding shutters; one of them is closed in
the cocked position and the other is open.  The cocking
mechanism is arranged so that the first shutter is closed
before the second shutter is opened (to avoid exposing the
film).  The shutter button holds both shutters in the cocked
position.  When the shutter is tripped, the first shutter is
opened and the second shutter is closed soon behind it; note
that if the second shutter follows very closely after the
first, there may not be any time when both shutters are all
the way open; for this reason, it's usually necessary to use
a shutter speed of at least 1/250-1/60 when using a flash.

On many electronic cameras, there is a small electromagnet
which holds the second shutter open for a certain length of
time after the button is pushed.  Since the magnet doesn't
have to "grab" anything, but merely hold it in place, it
uses much less current than a solenoid.  Further, since the
shutter button will hold the second shutter open until it's
pushed, it's only necessary to energize the magnet for what-
ever length of time the shutter has to stay open.

Note that this mechanism, as used in most cameras, is very
economical in its use of power, but it's not very adaptable to
external tripping (other than by using a solenoid).  Many of
the better 35mm cameras do have, though, a connector for a
mechanical shutter cable, so mounting a solenoid or similar
tripping device may not be too bad.  While solenoids do need a
fair dose of current, a solenoid in this usage would only need
it very briefly so the total energy requirement should be quite
reasonable.

1998\11\19@120336 by Dave VanHorn

flavicon
face
John Payson wrote:
>
> |I'd like to trigger a film camera from a pic.  Also it would be nice
> |to use a cheap auto wind type but I haven't been able to find any
> |that have an external switch for this.  I've thought about breaking
> |into the camera to get at the switch but it's not elegant.  A solenoid
> |plunger would work if positioned over the button but any I've seen
> |are really power hogs.  Does anyone have any ideas or tips they'd
> |like to share on being able to do this?
>

An RC servo would work here, they have a lot of torque, and you could
even power it down when not using it at the risk of an extra picture
during the powerup "twitch".

1998\11\19@165907 by Tony Nixon

flavicon
picon face
Have a look at my web site. There is a complete PIC controlled motor
driven camera project there.

http://www.picnpoke.com/projects/photo.html

--
Best regards

Tony

Multimedia 16F84 Beginners PIC Tools.

http://www.picnpoke.com
Email .....picnpokeKILLspamspam@spam@cdi.com.au

1998\11\20@064045 by Peter L. Peres

picon face
On Thu, 19 Nov 1998, Dave VanHorn wrote:

> John Payson wrote:
> >
> > |I'd like to trigger a film camera from a pic.  Also it would be nice
> > |to use a cheap auto wind type but I haven't been able to find any
> > |that have an external switch for this.  I've thought about breaking
> > |into the camera to get at the switch but it's not elegant.  A solenoid
> > |plunger would work if positioned over the button but any I've seen
> > |are really power hogs.  Does anyone have any ideas or tips they'd
> > |like to share on being able to do this?
> >
>
> An RC servo would work here, they have a lot of torque, and you could
> even power it down when not using it at the risk of an extra picture
> during the powerup "twitch".

For some pics and good descriptions of RC servo triggered cameras look up
'kite aerial photography' on the web.

0.02 Agorot

Peter

1998\11\21@225939 by Mark Willis

flavicon
face
Peter L. Peres wrote:
{Quote hidden}

 Another thought, something like a sear mechanism could trigger a
more-powerful spring-wound mechanism (i.e. a small movement of a catch
releases a powerful plunger for one stroke, just spring wind the
clockwork each time you replace the film.)  Something like the way
mechanical clocks work.  You can have a lot of leverage with a sear
(50:1 is quite a possible control ratio - i.e. 1 Lb pull releases a 50#
spring etc.)  Look at the way a rifle "Set Trigger" works, for one
example;  Also just a regular rifle sear etc.

 Mark, mwillisspamKILLspamnwlink.com

More... (looser matching)
- Last day of these posts
- In 1998 , 1999 only
- Today
- New search...