Timelapse settings

Shooting timelapse is really quite popular among photographers interested in showing the passing of time in movies. For many others though, its something they try and then run into problems when putting the images together into a sequence.

While there are several potential stumbling blocks the biggest issue is usually trying to avoid flicker in the final sequence.

Flicker is caused by differences in exposure between each frame of the sequence. While they may look mostly the same, slight differences are magnified when you play images back at 25 frames per second.

However, all is not lost – there are ways of minimising exposure differences in your images. The first, and most obvious, is to set the camera manually. This means setting ISO, aperture and shutter speed so they can’t change. It also means thinking of anything else that might change on a shot-by-shot basis and locking that down as much as possible too – notably White Balance. Auto White Balance, while pretty stable, could easily adjust during the shooting and that would leave you with a colour shift (see the video for an example of this). For complete control, you should also set your Picture Style to something like neutral (as if you were shooting HD movies), but this is less of an issue and less likely to cause flicker problems.

If you want full control of your images after shooting, then don’t shoot in JPEG – you don’t need the full resolution of RAW files, but many EOS models feature an sRAW function. This is typically 25 or 50% of the full resolution but still provides all the benefits of RAW files, namely the ability to accurately adjust exposure and white balance. The down side is that they are larger than sJPEG files and you will fit fewer images onto a memory card.

Back to flicker – the main cause is actually the aperture. EOS cameras feature an aperture that is accurate to within 1/10 stop but even these tiny changes can show in the images when played back. Locking the aperture down in manual is a good start, but there is an even better way – set the aperture to maximum i.e. f/2.8 for a lens with a max aperture of f/2.8. If you’re shooting sky at night images this should not be a problem and the advantage is that the aperture doesn’t have to close down and you will therefore avoid the slight aperture variations. If you’re going to do this, then make sure you understand depth of field and hyperfocal focusing to ensure you get adequate depth of field for what you want in focus. With stars, you don’t actually need depth of field as you will be focusing at infinity giving you quite a lot of depth of field anyway.

For daytime shooting, clearly shooting with an open aperture is going to require some fast shutter speeds, even at low ISO settings. This is where a Vari-ND filter, as used by those shooting HD movies on DSLRs, will come in handy. Simply dial in more ND until you have the shutter speed you want, even with the aperture wide open.

The other solution, and far be it from me to suggest you look elsewhere…. is to buy an old manual lens with a manual aperture ring. It doesn’t even have to be a Canon lens. Simply get a conversion ring to adapt it to the EOS fit and lo, you’ll find no aperture change and therefore much reduced flicker in timelapse sequences.

The sequence below was shot using the ‘open aperture’ technique, though the white balance setting was left on auto hence the white balance bounce half way through.

TimeLapse example in Costa Rica from EOS Network on Vimeo.