Focus & Colouring

Right so your all ready to go.. you point your camera at the water and.. what DO you focus on?

The drops come too quickly to see clearly and one bit of water looks pretty much like another.

What I do is set the drops going and then lie a bread knife across where the drops hit the water. (Why a bread knife?.. it has a nice serrated edge thats easy to focus on). If your doing single drops then have the edge that your focusing on JUST in front of where the drops are landing. If you are doing impact splashes that you want to go out then move it so that you are focusing between 0.5cm and 1cm in front of where the drops land.

SET TO MANUAL FOCUS!! (I always focus up, then hit the button and it tries to autofocus and I have to go back to focusing again! :)

This is where having live-view and an option to magnify the screen comes in REALLY handy!


Other stuff I have used.. Piece of string across where I want to focus, pipe cleaner (really fuzzy works very well!) you can use pretty much anything.

Now you have to see what you want to do to make the stuff stand out.. I'll go into this in more detail at a later date but here's some ideas.

Plain water does not look like much, no contrast between it and the background and it does not reflect light it refracts whatever is behind it.

Backgrounds
Put a background behind the drop, colourful, stripy pictures, a nice flower, anything can be a background, all give different effects.



Flash Gel's
Put some clear gel plastic infront of your flash and it will turn everything that colour. I've used a red plastic beaker before with some nice effects. 2 flashes with different colours can give some amazing looks. (I only have one flash at the moment, have experimented with covering half with different colours.. kinda worked)



Dyes
These can work really well.. Different colours in the bowl of water and in the droplets can make some great effects. Can be messy!!

Also once the two colours start to mix you can either end up with non-photogenic sludge or something quite unusual.. never sure what you will get.



Experiment.. try.. see what different colours you can get..

Chris

Light, Motion and Depth of Field

Here's how I understand this... (I'm not an expert in this....)

Higher (smaller) aperature = wider depth of field
Higher aperature = more light needed to take a picture
More light (bigger flash) = slower (longer) flash = more motion in your drops
AND... Distance to target (size of final image)

So you have to trade off Aperature (DOF) vs Light vs Distance to target to come up with a reasonable middle area that gives you acceptable depth of field that's well lit.

If you are photographing simple droplet's like :



Then it's moderately simple.. the DOF is not very wide (depending on the angle you are photographing from) so you can use a moderate aperature. The DOF needed on this picture is probabily no more than 4-6mm.

However if you are trying to take a picture like :



You can see that the required area to be in focus is MUCH wider. If you look in large then you can see that the drops to the side/back are actually out of focus. But as the ones at the front are in focus then it does not look too bad.

How do you do it?

http://eosdoc.com/jlcalc/

This is a great calculator for figuring out your depth of field using almost any equipment. Put in how far you are from the target, focal length etc and it will tell you how wide your DOF is.. I try to aim for a minimum of 12mm

However with only 1 flash (Vivitar 285) set to minimum power with water I get really dark pictures without dropping down ISO to around 400 and aperature to F13/F14. Milk is a lot easier as it is opaque and reflects the light so even at F16, ISO100 I can get nice brightly lit pictures.


Tips :
Have a look at the calculator and see what DOF you can get at what distances etc
Take some test shots and see how they come out and work out what you want to sacrifice.

My standard settings (for milk drops)

Canon 100mm Macro :
Distance 34cm (ish) works out to be around 1:3 magnification
F16, ISO 100

55mm M42 lens + 12mm extension tube :
Distance 29cm (ish) works out to be around 1:4.2 magnification
F16, ISO 100

For water drops probabily go to F14 & ISO 200 at the same distances.

You *can* increase the power of the flash you are using.. so you can use higher aperature.. HOWEVER this will mean the flash will be slower and so you risk introducing movement into the final shot.

Try. Experiment, see what works, fiddle around a bit.. and take lots of pics!

Last Night's Drops - Cream Crowns

I made these...



and..



After seeing

I had not realised how HARD it would be to get a single crown like this..

There's a few challenges.

1). You need to drop a single drop of milk ACCURATELY into the centre of a small drop of milk/cream on the surface below.

2). You need to trigger the flash just as the crown forms.

3). If you muck it or the crown does not form.. You have to completely reset from scratch and do it all again.

This is really hard and mind numbingly repetitive.. I guess a photogate trigger would make this easier as you would be more likely to trigger on the crown forming and have to do it fewer times.. I dont have one, In the end I setup and shot around 120 times.

What's needed

4 eye-droppers, milk, cream, coloured dye, shiny reflective surface, 2 flashes

1. Setup one dropper in a fixed position above the shiny reflective surface (I used the handle of a cheese grater that had a small hole in it (for hanging) with a weight on the other end)
2. Mark the position that drops fall from the dropper
3. Focus camera on the position that you marked so DOF is all around that area.
4. Use one dropper to make a small (0.5cm) drop of milk exactly where the drops form.
5. Use the other two droppers to dye alternate sides of the drop with different colour food dyes.
6. REALLY quickly before the dyes mix, trigger your camera, drop a drop from the first eye-dropper and trigger your flash when you think it's hit. (Requires 3-4 hands!.. not easy if you do this on your own ;) )
7. Check picture on your camera.. If it's no good then clean up the target area (carefully so it's still shiny) go back to 4 and start again.

If your lucky you might get something that's half decent.

Not recommended for the impatient!