Stacking Venus

Since I took my pictures of the transit of Venus I have wanted to combine the images so that you can see Venus’s progress across in the Sun in one photo. Being the incorrigible do-it-myselfer, I of course started browsing the Internet for suggestions and ideas instead of talking to some of my co-workers who would probably have pointed me in the right direction much faster.

I was eventually referred to a free image-stacking program called Lynkeos. It was very easy to use. All I had to do was load my photos, select a region on one that the other images should line up to and press go. Unfortunately the end result was a very fuzzy off centre rendition of the transit.

Stacked images of Transit of Venus 2012 Ottawa Ontario

Stacking my images using Lynkeos


I confess that the problem was likely my photos that were taken without being mounted to my telescope that in turn didn’t have any form of automated or smooth manual tracking for keeping the Sun centred. I’m holding on to Lynkeos to test it out in the future as I think it will work quite well as my photography skills improve.

Realizing that I needed to do a lot more manual manipulation of the photos, I looked for a photo editing software and found several sites promoting GIMP, a free photo editing software. I started playing around with it, reading and watching some tutorials online.  I was soon rotating and aligning images, cropping and adjusting. I eventually managed to combine my photos into something close to what I wanted, more by fluke than by know how, but I am still pleased with the end result

Transit of Venus 2012 Ottawa Ontario 30 min time lapse image

My combined photos of the transit of Venus.

Transit of Venus Photos

I managed to catch the transit of Venus while in Ottawa for my girlfriend’s graduation. We set up outside the Museum of Nature and we saw a good half hour of the transit. Unfortunately I didn’t get that many good photographs, but here are a few of them.

Venus at the start of ingress.

Getting closer.

Venus just after ingress.

About 30 min into the transit.

I also tried my hand at timing the transit, which was a fun challenge. Here are the times I got compared to the predicted times.

My Times (EDT)

Predicted Times for Ottawa (EDT)

Contact I



Contact II



I have to confess I was looking in the wrong corner of the sun through my telescope to properly catch the start of ingress and was fooled by the infamous black drop effect for a proper timing of the end of ingress, but it was still fun to time the ingress. Although I think you need to have times for the whole transit (not just ingress), I hope this might be enough to use parallax to calculate the distance to Venus providing my friends in Winnipeg managed to write down their times as well. It would be kind of exciting to follow in mathematical footsteps of previous transit watchers and try and figure out the size of our solar system.

Come See Venus With the RASC

The Winnipeg Centre of the RASC will be at Assiniboine Park at site #15 (near the baseball diamonds) for the transit of Venus. As with the partial solar eclipse of May 20th, they will have a few telescopes with proper solar filters on hand for the public to look through.

The transit starts at 17:00 (5 pm) and ends after sunset.

Transit Timeline For Winnipeg

Contact I(Ingress Begins) 17:04:36 (5:04:36 pm)
Contact II(Ingress Ends) 17:22:12 (5:22:12 pm)
Sunset 21:32 (9:32 pm)

SAFETY WARNING: You should never look at the Sun with unprotected eyes! The ONLY safe way to observe the sun directly is by using a special solar filter. Sunglasses, CDs, solar blankets, and other materials are NOT safe, because they do not filter out the invisible radiation from the sun. Solar filters which are SAFE to use: #14 welder’s glass (no other number is safe), and eclipse glasses made especially for solar viewing.