If you missed the opportunity on June 8th 2004, this Wednesday morning at sunrise is your last chance to engage in a little astronomy and get your own picture of Venus transiting the Sun.

Last chance that is, assuming you are not going to be alive in December 2117 when it is visible from Earth again.

Getting an image is surprisingly easy as long as there is no cloud cover which is about the only thing that will make it difficult this Wednesday. To get a decent picture, you need a pair of binoculars (which you are not going to look through), a sheet of white card, a tripod or other device to hold the binoculars, a camera and a dark room or space from which the Sun will be visible at sunrise on the 6th.

To set up your equipment (which I would suggest is done tomorrow (Tuesday) to avoid buggering anything up), arrange the binoculars on the tripod facing the sun and adjust the angle until the sun projects through one eyepiece onto your piece of card – DO NOT look through them or you won’t be looking at anything again with that eye! The easiest way is to hold the card near the eyepiece and move the binoculars around until you get an image of the sun. Lock the tripod adjustments in place and then move the car away from the eyepiece until you have a suitable sized image of the sun on the card which you can take photographs of.

A darkened room or space with a hole for just one binocular lens works best so get to work with some black plastic sheet and tape to create your darkroom (you see why I suggest setting up in advance now). I blacked out the windows on my Landrover last time after parking in a suitable place and had the binocular poking out the passenger window through a hole in the plastic although 8 years later this would probably get you arrested for something!

When the time comes (in the UK this will be at sunrise onwards but check the link above for times in other places) start taking photographs of the Sun’s projection – I would suggest taking as many shots as you can with varying exposures. As the Sun’s image will appear very bright in your darkened space it is best to use a camera which will allow manual adjustment of the exposure so you don’t get a washed out image. If possible, check a few images while it is still happening to check you are getting usable images.

When it’s all over and you have dismantled your apparatus, get your photos into an image editing program and adjust the brightness and contrast to give the best results.

I will be having a go at this on Wednesday morning but the weather forecast isn’t looking too promising at the moment. Having said that, I may leave it all set up and try and get some photos of sun spots which can be obtained in exactly the same way.

Two of my own images from the last occasion are below – one from 07:45 am and one from 11:50 am, both on June 8th 2004 showing just after the start of transit and just before the end.

Have fun and don’t burn out a retina by looking through the binoculars!