Tim Trentadue volunteers at two different dark sky sites for public outreach, and with two events each month from May through October, he has “plenty of opportunity to discuss everything astronomy.” 

And this he uses to help with outreach — the Trifid Nebula, Messier 20 — garnered him Photo of the Week.

“Using my pictures really helps when explaining the different types of nebulas. This image has the three most common types—emission, reflection and absorption—so it is an ideal teaching aid,” he wrote in an email. “The beauty of this nebula definitely helps in piquing people’s interest in astronomy.”

Trentadue said he captured the image June 4, 2019, at the North Frontenac Dark Sky Preserve in Ontario. He has shot this object before with a DSLR, but now has a dedicated astro camera—the ASI 1600 mm Pro. 

“I was anxious to see what this new addition was going to produce for this object,” he said. “I was really surprised at how well everything came out. This object never gets very high for us here in Canada, so I took a chance one night and changed my primary target to shoot M20 instead.”

The night was exceptionally calm and the southern sky was looking very clear when he decided to shoot. “Tracking is not always good when shooting low in the south, so this presents its own challenges,” he added. “When all is said and done, this is my best image of M20 to date, and I am very happy with it.”

Trentadue said the image was a combination of LRGB and Ha data. He said he shot: 10 x 120 seconds R, 10 x 120 seconds G, 10 x 120 seconds B, and 12 x 300 seconds Ha. 

He also used a TS 130 APO f/7, SW EQ6 Pro, ZWO 1600 mm Pro @ -20 Unity Gain, ZWO EFW 7pos LRGB Ha Oiii Sii, Orion Mini 50mm Guide Scope with an Orion SS Autoguider, and a Pegasus Astro Electronic Focuser. 

His capture and processing software included Sequence Generator Pro, PHD 2, PixInsight, Photoshop and Deep Sky Stacker.