Saturday, 14 July 2012

Stop That Train...

... I wanna get on

When you don't have a clue how something works you have a few options. You can get someone to tell you about it. You can read the manual. But probably the most fun is just to get out there and start pressing a few buttons and twiddling a few dials.

Here I found myself waiting for my train so I thought I'd try mixing flash with natural - well, ambient - light to see what happened. The results are below.

I also couldn't help myself and played around with the amount of flash as well as front and rear curtain triggering, oh yeah!

The first picture below is with -1 stop of flash, the second with -3 stops and the third with no reduction.

But what I really wanted was a couple of shots demonstrating the  difference between front and rear curtain firing. What that means is that with a slow shutter speed like I'm using here (1/6th second) you can choose whether the flash, which is far faster and briefer than 1/6th of a second, fires at the beginning of the time the shutter is open or at the end.

All that might sound like gobbledegook, or at the very least pretty useless, but it can produce interesting results, especially with moving subjects.

In the first picture it's front curtain firing. In other words the flash fires right at the start of the exposure. What this does is freeze an image of the on-coming train at the start of the time period. But the shutter stays open longer than the flash and the ambient light - the lights of the platform here - continue to register a blurry image as the train comes towards you. This slightly obscures the once sharp flash image recorded at the start of the exposure.

In the third image I've done the opposite, with the flash firing at the end. So the last thing that happens is that the blurry ambient image is 'capped' with the sharper flash image. You can see this in the clearer letters on the front of the train, and the direction of the trailing lights.

Personally, I think the third image is the stronger.

Nikon D800  F/9  1/6s  ISO-1600  PrSH  EV 0  24mm

Nikon D800  F/11  1/6s  ISO-1600  PrSH  EV 0  24mm

Nikon D800  F/8  1/6s  ISO-1600  PrSH  EV 0  52mm
In the end though I've played around with another shot I took with a stationary train and a couple of guys hurrying for it.


The effect's pretty curious, with the guys looking semi-transparent. This is because they were moving fast and  the flash froze them but only registered them where they were wearing something light, like the guy's white shirt and his skin.

Can you guess if the flash was front or rear curtain firing? The light trails on the guys leading up to the crisp image should tell you that it was rear curtain synched, right? More later!






And why not...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


* Sab Will runs Photo and Curios Tours in Paris, and also manages a variety of Paris and photography-themed sites and blogs. He writes an illustrated Paris Chronicle every day, runs a Meetup group for Paris lovers, interviews Paris personalities and reviews Paris books (on this blog), and even contributes to the city's street art (shh), so feel free to browse some of the links below and in the right-hand column to find out more about what he gets up to out there...

                        
_________________________________________________________________________________
© 2012 Sab Will / Paris Set Me Free - Contact me directly for photo tours, interviews, exhibitions, etc.

No comments:

Post a Comment