2015 Perseid Meteor Shower

On the Night between August 12-13 2013 me and my father ventured out to Mt. Horeb, ON near Omemee to witness this year's stellar Perseid meteor shower. The night started out with a few clouds, but at around 2:30am the clouds all dissipated as the shower's radiant near zenith and the showered peaked. WOW, what a sight, from faint little shooting stars to several fireballs, This years' shower did not disappoint. At one point we were seeing about one shooting star every 20 or so seconds. According to the International Meteor Organization, the rate was about 85 meteors per hour during the shower's peak.

Milky Way over Rochester, NY

Milky Way over Rochester, NY across Lake Ontario, From AJax, ON, taken on August 6ᵗʰ 2015 Settings: D3200, 18mm, f3.5, ISO3200, 15x 15sec 3min45sec total stacked with DeepSkyStacker,  processed with RawTherapee and Gimp

Milky Way over Lake Ontario

Last night I decided to go for a walk before going to bed. Naturally I brought my camera along to take some pictures of the night sky over the lake. Even with the heavy haze and light pollution from both The Golden Horseshoe and Rochester,NY, I got some pleasing results.

Settings and Processing: 18mm f3.5 3min45sec total stacked from 15x 15sec at 1600ISO and 2 dark frames, stacked with DeepSkyStacker 3.3.2, processed in RawTherapee 4.2.238 and Gimp 2.8.

Deneb

Last night the clouds broke and the sky cleared. This 6 minute exposure shows the star Deneb prominently on the left side of the image as well as some nice red coloured nebulosity and the rest of Cygnus to the right. Taken with my Nikon D3200 60x 6sec ISO6400 exposures at 55mm stacked in DeepSkyStacker and processed in Rawtherapee.

A quick comparison...

Below are a quick comparsion between the method used in my last post (first photo) and developing a single exposure (sencond photo).

As you can see the results are somewhat comparable, with one major difference. The first photo technique (using the stacking method) reduces the amount of noise in the image considerably.

Here is another example:

Amateur DSLR Astrophotography

I've decided to put up a quick tutorial on taking some nice pictures of the night sky in less than perfect light polluted conditions. The results won't be anything like some of those amazing shots obtained from dark sky sites but they will still provide some nice shots. Like this one:

Tools you will need:

• A camera on a sturdy surface (a DSLR on a tripod works best) that can shoot in RAW format (jpegs won't look as nice and are usually to noisy) and shutter speed can be set manually.
• A way to take a sequence of photos in a row (an Intervalometer of some sort)
• Deepskystacker
• Rawtherapee
• Gimp

Steps:

1. Locate your target. In this case I aimed my camera at the the Milky Way around the constellation Cygnus.
2. Take a couple of test exposures using the rule of 600 and the highest ISO that you can without getting too much noise (a small amount of noise is OK since the stacking will take care of it). Tip: focus on a faraway street lamp with the camera's auto-focus and turn it off, this will get you a focus onto infinity.
3. In my case setting the focal length to 27mm and the f-stop to 5.6, ISO 1600 and 10s shutter and daytime white balance, yielded the following result:Not bad some of brightest stars can be seen and they are in focus!
4. Set the camera to take a large numbers of exposures in a row (These are your Light Frames). Use an Intervalometer, or in my case I connect the camera via USB to my laptop (using digiCamControl) or my android phone (using qDSLRDashboard). In this case I set the camera for 30x 10sec exposures giving a total exposure of 5 minutes.
5. Once the camera is done taking the photos take a few dark frames, by taking 3 shots with the SAME SETTINGS but put the cap back on.
6. Finally take a bias shot by keeping the cap on and increasing the shutter speed to the highest your camera is capable of (usually 1/4000 or 1/8000)
7. Both the Dark and Bias frames MUST be done at the time your Light Frames are taken
8. Now upload the photos to a folder and launch DeepSkyStacker
9. Click on Open Picture Files… and load your light frames
10. Click on Dark Files… and load the dark frames
11. Click on offset/bias files.. and load the bias frame
12. Go to RAW/FITS DDP Settings and Check Auto White balance and OK
13. Click on Check all
14. Click on Register Checked pictures…
15. The default setting are OK, you can later play with them or look at some other tutorials on how to tweak them.
16. Hit the OK button, sit back and relax. Depending on your number on Pictures and hardware this could take quite a while, my case took around 35-40 minutes on a not to fast laptop. Your mileage will vary!
17. When DeepSkyStacker finishes it will create this:Umm not much to see…
18. Open the Autosave.tif in Rawtherapee
19. Play with the sliders until you get something like this (a future tutorial will deal more with this in detail):
20. Hurray, you are almost there. Save it as an 8 bit tiff.
21. You probably notice the colour is not quite right and the edges are fuzzy. To fix this develop and save 3 of your best exposures from the set and load them on Gimp.
22. Using the G'MIC plugin, blend the 3 photos as layers using the median option to get rid of the stars.
23. load the saved 8bit tiff from above as a layer over this one and create a grey scale layer mask. (You may need to do some tweaking to the layer mask's contrast to get better results.
24. That's it! You should get something close to this: