Snap a drip

[granddad]

A friend who is well into his photography ( a BA no less ) was chatting about shooting water drips. Problem is, it requires a timer / trigger . He had seen an Arduino setup and was considering going down that road, “ What did I think” (Mmm Not for a total mcu newbie with no ‘Electro’ background ) So being a PIC nut, I offered to build a timer for him , more or less from parts I had to hand. Well although it looks like a crazy machine, it turned out better than either of us expected ! Still not 100% but as my mate said “Getting there”
The prototype PIC18F14k22, 2x16 LCD, rotary encoder, switches and two opto couplers ( Think I needed to keep the 12volts well away from his thousand pound Canon camera) the timer gave millisecond accuracy ( 1 to < 3000ms ) for the valve and the camera trigger.
{ if you would like my very "amateur" C code , PM me }

 

[atferrari]

What triggers the timer?

 

[JimB]

A great practical application, thanks for the show and tell.

I love the prototype assembly, something which just grew and grew.

JimB

 

[granddad]

What triggers the timer?

After the set-up of the D1 ( valve timer first drip ~20ms ) [next] D2 ( second drip , same valve) .[Next] D12 time between drips , [next] C is delay( D1 to Camera trigger) {[Next] RUN , enables the run button .. stays in RUN untill [next] cycle repeats..
His Canon camera has a 3 pin 2.5mm jack cable for a remote trigger,

 

[Nigel Goodwin]

Going back a VERY, VERY long time Practical Electronics did a flash trigger using audio detection and a variable monostable to delay the flash after the sound was detected - they showed some amazing pictures in the article. Your picture is great as well.

 

[Visitor]

Hmmm. My Pentax SLR has an IR shutter remote. It might be too slow, and perhaps not repeatable enough, to allow doing something like this.

 

[granddad]

As far as I'm aware my photo man has an open shutter at the 'splash' time also a high aperture f22 for depth of field, also some mega expensive lens ! theres also a Apple laptop connected somewhere , I've not seen the 'Drip action ' due to covid rules . The whole setup, valve, water,camera etc within a 'dark ' enclosure, He then fires a one or two high speed flash units.. ( Be prepared for lots of time spent adjusting things )..

 

[Visitor]

Ahhh. Nice way to do it.

At least it's far simpler now with digital cameras than with film cameras! Can you imagine shooting 24 shots then waiting a week to see if any of then turned out?

 

[Nigel Goodwin]

Hmmm. My Pentax SLR has an IR shutter remote. It might be too slow, and perhaps not repeatable enough, to allow doing something like this.

I've got a book somewhere, my wife bought it me for a present, all about high speed stills photography with LOT'S of great example pictures.

The main issue was shutter speed, and as I recall he overcame this by using small explosive charges to move the shutter fast enough.

 

[Visitor]

Now that you mention it, I recall that the mechanism granddad described has been used for the same reason. The flash can be far faster than a shutter.

 

[Dan Soze]

You should take a look at this book:

Stopping Time: The Photographs of Harold Edgerton

Edgerton invented the electronic xenon strobe light, and a lot of other stuff.