Trying to light the rocks

Picture the scene.  It’s early on a Sunday morning.  You’re on the rocks near Sandycove in bad light.  You’ve just done some HDR stuff to try to get a decent shot from that bad light, but you want to try something a little more conventional by creating a shot in the camera instead of in post processing.  You have a few Nikon Speedlight flashes in your bag that can be triggered remotely.  It’s time to light the landscape yourself.

That was the line of thinking I followed as I turned 180 degrees on the rock on which I was standing when I took yesterday’s shot so that I could frame a shot of the rocks behind me.   Now the sunrise is behind me, and an ambient-only exposure of this scene is just going to show up the really poor light that I am shooting in.  Much as I did a few months ago when an evening outing to the War Memorial Gardens failed to coincide with spectacular twilight conditions, I decided to see if I could light the scene myself using artificial means – namely those three Nikon flashes that I had in my camera bag.

In hindsight I went about this completely the wrong way around – I’ll explain why in a moment, but first the process I used to set up the shot.

Firstly, I took an ambient exposure of the scene (which you see on the right below as it is straight from the camera via the RAW converter).  You can see what I mean about that flat light (and in particular, a washed out sky).  If I am going to craft some definition in this scene using flash I need to take the ambient light down a few notches to give me a base upon which I can add light.  If I just fired flash at this scene as it is, you’d hardly notice because they would be overpowered by the day light.

So step 1 is to underexpose the scene by about a stop and a half.  I decide to keep depth of field, and so I adjust my shutter speed to achieve the underexposure.  I’m still shooting at ISO 100 after the previous shot, but have opened up my aperture to f/16, primarily to just avoid the extreme end of the aperture where the lens is likely not to be at its best.

I spend the next five minutes positioning and repositioning lights around the scene.  Unfortunately, for reasons I’ll explain shortly, I never got a setup shot so can’t show you where they were, but I ended up with three – one to my right pointing at the biggest rock at frame right, one behind me to my left, low down and throwing some light on the rocks at bottom left of frame, and one off to my left, slightly in front of the camera, and throwing a wide beam of light onto the rocks closest to the centre of the frame.

There’s a balance with this type of photography between having the image scream that it is artificially lit, and failing to have your flashes make any impact on the scene.  I scored probably 2 from 3 on this front.  The flash to my right is certainly adding a nice highlight to those rocks on the right, and, as it turns out, probably saves the frame.  The other two are less effective.

As I’m pondering why this is I encounter a problem.  A big problem in fact.  Noticing that my foot has just been splashed a little, I look around to see that the ledge on which I am standing, and on which my camera bag is sitting, is very close to becoming submerged.  More than that, water has been pouring in to the scene in front of me via a little channel just to my right, and the rocks on which my flash that does a good job of lighting the scene is sitting are quickly becoming islands.  My flash is about to be cut off from the mainland.

I very quickly hoist my bag up to higher ground further in land, go grab my flash from the soon-to-be island, and just get back to retrieve my other two flashes before the water really starts pouring in.  When I look back at the test frames I’ve shot before the image above I can clearly see the rising water – look at the difference between the ambient shot and the final shot above for instance.   So abruptly, and before I could really solve the problem of two of my three flashes not adding a lot of light to the scene, my shoot is over.

So what did I do wrong?  Well firstly what did I do right?  Underexposing the scene was the way to go – it brings detail back into the sky, and had I been able to have time to get the two flashes to my left throwing adequate light on the scene, I would have been able to craft more pleasing highlights on the rocks and more areas of interest for the viewer.  And hopefully you can see from the rocks to the right of the final image that the idea was working.

Here’s the thing though – those flashes were all at full power. The one on the right was my SB-800 so it had more power than the other two (and, obviously, enough to overcome the underexposed ambient).  The other two were still struggling even at full power.

Take a look at my exposure settings again and all becomes clear: f/16 @ 1/5s, ISO 100.  While underexposing the scene was the right thing to do, it is how I underexposed it was the problem.  Firstly, the ISO here is way too low – it affects both the ambient exposure and how much light from the flash hits the sensor, so by having this low, I’m already squelching the effect of my flash.  Same goes for the aperture – it is way too small.  Ok I wanted depth of field, but had I gone from f/16 to f/11 I’d have effectively doubled the impact of each flash.  Combine this with an increase in ISO from 100 to 400 and I’d have got the same light from my SB-800 at 1/8 power as I was in this shot at full power.  And presumably the other two speedlights would have been able to throw much more light onto the final image too.

But had I shot this at f/11, ISO 400 then how would I have underexposed the ambient?  Simple – instead of 1/5s, I could have gone to 1/40s.   Those settings give me the exact same ambient exposure as f/16 @ 1/5s, ISO 100, but the flash element of the exposure is boosted by 8.  Meaning that I have a LOT more room to play with in terms of flash power and sculpting the light on the rocks.

Sadly, all this dawned on me far too late and the tide meant I couldn’t go back and do things properly.  I’ll know next time though.  At least the right hand side of the frame proved the theory, even if the left hand side of the frame is a case of what might have been. And at least I didn’t lose an SB-800.