Posts by Category: strobist

Puddle-Jumping Domo

Posted by Caz on Saturday, 26th November 2011

I thought I would get Domo to help me with today’s picture. This was the setup:

Domo Splash Setup

Domo Splash Setup

I was using the microphone sensor to detect the noise of Domo jumping into the puddle. The camera was set off automatically on bulb (f/18) and 70-90ms later the flashes went off. This is the first time I’ve used my 5-flash setup. More details on flash setup and power in this video:

The hardest part was training Domo to jump in the puddle and stay upright. He managed it a few times. The best was the one I chose for Day #1426. But there were some amusing outtakes too:

Slippy

Slippy

Slidey

Slidey

Faceplant

Faceplant

Bumslide

Bumslide

No Smoke Without Fire

Posted by Caz on Wednesday, 9th November 2011

I have photographed smoke trails and shapes before, but thought I would see what I could get today by using the microphone sensor and Camera Axe to time the shots.

Here is my setup diagram:

Mic Sensor and Matches Setup

Mic Sensor and Matches Setup

And the actual mini studio in the kitchen:

Studio setup

Studio setup

CameraAxe setup menu

CameraAxe setup menu

Back to the General Sensor setup menu for this shoot. Sensor 1 (the microphone) was set as the trigger for both camera (device1) and flash (device2). I set the delay on the camera to 0ms – I wanted the shutter open right away.

Experimenting with the flash delay gave a value of 350ms which showed some interesting smoke patterns once the “huff” of blowing out the match had triggered the mic sensor. The threshold value was set quite low for this – 040/20 (ambient noise) which meant it was very sensitive to any noises, including blowing out the flame.

Spent matches

Spent matches

The camera was set at ISO100, bulb and f/14. The CAS5 was holding the camera shutter open for a 1s exposure – but of course the only light available during that time was the high speed flash set to 1/32 power.

I burned through quite a lot of matches! But thankfully no fingers or cables, so that was a small price to pay.

Then, as with many of these things, it was just a case of playing about and repeating the process over and over until I got some interesting shapes.

Here is a small selection:

Whisps

Whisps

Match Blister

Match Blister

The Dancer

The Dancer

My favourite of the day turned out to be The Smoke Dragon – which I think Dai had something to do with organising! I also found a good image for today’s MoNovember shot.

Water Drop Collisions

Posted by Caz on Monday, 7th November 2011

After my recent success with the CameraAxe5 and the Microphone Sensor, I thought I would have a go at some shots using the Valve sensor today.

Here is the Camera Axe setup:

Valve Sensor Setup

Valve Sensor Setup

The valve sensor is plugged into Sensor Port 1 of the Camera Axe. It has the droplet size and delay controlled from the Valve Sensor Menu. The camera is plugged into Device Output 1 – using Bulb mode at f/11 and manual focus. The first flash is plugged into Device Output 2 and is set to go off after a short delay once the first or second drop has left the valve nozzle. The second flash is fired from the first via visual slave mode. Here are some setup shots:

General setup

General setup

Kitchen studio

Kitchen studio

Valve Sensor Details

Valve Sensor Details

Getting Started

First things first – you need to know rough timings for events with just ONE drop coming out of the valve sensor. For my first set of shots, I set Drop1 Size at 40(ms), Drop2 Size at 0 (ie no second drop) and varied the flash delay in 10ms increments between 200ms and 400ms to observe where the drops were during each time frame (dropping from a height of 330mm). The stop-motion animation on the right is composited from one frame taken at each flash time delay value.

This is an important step, otherwise you could be spending ages trying to catch the right moment via trial and error. If we use a bit of maths, however, we can get much nearer the predicted event straight away. There is more of an explanation at the excellent Camera Axe Valve Sensor tutorial page.

Valve Sensor Setup Menu

Valve Sensor Setup Menu

From the frames already taken, I decided that I wanted to have the 2-drop collision take place once the first drop was “on the rebound” and at the top of its “spout”. This gave me a delay value around 32oms. Looking at the motion to see where the second drop should be to collide with it, that gave a value around 230ms. The sums give us:

Pos1 (320ms) – Pos2 (23oms) – Drop1 size (40ms) = Drop2 Delay (50ms)

and

Pos1 (320ms) – Drop2 Delay (50ms) – Drop2 size (40ms) = Flash Delay (230ms)

So, plugging these values into the Valve Sensor Menu (see above) should get us in the right ballpark for a collision. I was desperate to try this out, but just as I’d got the vital numbers worked out, the rechargeable batteries in one of my flashes went flat! Since there was already a set on charge and no spares, I had to nip out to buy some disposables before I could give it a whirl. After taking one shot, I did a little bit of tweaking , as I noticed the flashes were going off a bit too soon for the interesting action. So I upped the flash delay to 245ms. And here we are – my first collision shot!

Valve Setup Menu: D1 (40), D2D (50), D2 (40), FD(245) ms

Valve Setup Menu: D1 (40), D2D (50), D2 (40), FD(245) ms

Getting Creative

Then it was time to play! Vary the delay and see what happens…

Oval Splash

Oval Splash

The Anti-Gravity Hat

The Anti-Gravity Hat

Mushroom And Raindrops

Mushroom And Raindrops

Tilted Sombrero

Tilted Sombrero

So that’s it for the moment. My favourite for the day was Frilly Skirt. I want to concentrate on some better lighting behind the splashes next time, but I need to wait for my new cable to arrive so I can run both flashes via the wireless TX unit. Then I can place them a lot further away from the CameraAxe electronics. But I’m pretty pleased with my first efforts at water splash collisions. Now that I’ve done a few shots, I should be able to get set up and running a lot quicker next time around.

Soap Opera

Posted by Caz on Monday, 11th July 2011

I’m easily distracted from household chores, especially where the washing up is involved. So it was no surprise that I got sidetracked into photographing soap bubbles this evening. It’s a very simple setup:

Soap Bubbles setup - one softbox from the side

Soap Bubbles setup - one softbox from the side

I started off with a small glass full of water, and added plenty of washing up liquid. Bubbles were blown in this with a straw, producing a rather nice head.

Once again, I’m using 1/200s shutter speed, ISO 200 and an aperture of f/20. Without flash, this gave a black frame. The bubbles were lit from one side, very close, by my DIY sotftbox @ 1/32. I had my macro lens on manual focus and shot in hand rather than on a tripod – I was able to react much more quickly to the rapidly changing (and popping!) bubble structures. The low flash power meant the exposure was very short, (of the order of 1/20,000s) so I didn’t have any worries about hand-holding the camera.

Here is a small selection of the best images:

Soap Spheres

Soap Spheres

Underground, Overground

Underground, Overground

Bubble Study

Bubble Study

Soap Film Abstract

Soap Film Abstract

Compared to my recent water splash images, these are pretty easy to take technically, you just have to watch the bubbles carefully and see what’s interesting. My favourite made it for Day #1288.