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Light-Pollution

Deep Sky Astrophotography in Light Pollution

|Nebulae|5 Comments

If you’ve been following AstroBackyard on YouTube, you’ll know that I regularly shoot DSLR astrophotography images under the heavily light polluted skies at home. My night sky is classified as Bortle Class 8 in terms of sky quality, a white zone on the light pollution map. This certainly makes things more difficult in terms of collecting data and image processing, but I welcome the challenge.

It’s true, there is no substitute for dark skies. But being able to set up a portable astrophotography kit in the backyard on a weeknight is pretty cool. I don’t have to pack up heavy gear into the car and worry about mobile battery power or internet access. I can open up the garage door and start capturing images through my telescope before it gets dark after work.

light pollution map

I live in the center of town, a red zone on the light pollution map

Don’t get me wrong, I adore traveling to dark sky locations, it just doesn’t happen as often as I’d like it to. For me, a typical night of deep sky imaging happens during the week in between work, family time and lots of dog walking. A clear sky in the backyard is my idea of the perfect night, no matter which target I’m shooting.

I’ve been successfully capturing deep sky images from this light polluted backyard for 3 years now. The best part about it is that I get to show others that live in the city that deep sky astrophotography is not only possible, but you can capture some truly incredible images. In this post, I’ll share my latest results from the backyard using a Canon EOS Rebel T3i DSLR camera and a small refractor telescope.

deep sky astrophotography

The Soul Nebula captured with a Canon DSLR and the equipment shown below

Light pollution is a major side-effect  of urbanization, and is said to compromise your health and can disrupt ecosystems. To discover the amount of light pollution where you live, simply locate your house on this interactive light pollution map. The Bortle scale is a way of measuring the brightness of the night sky.

Photographing a Nebula from the City

After much deliberation, I have decided to dedicate an increasingly rare and precious clear night to the Soul Nebula in Cassiopeia. I’ve photographed IC 1848 before, so I’ll be combining the new images I take with the previous data to create my best image of this emission nebula yet. All of the data I’ve ever collected on this nebula was shot here in the backyard with a DSLR.

My secret weapon is to collect absolutely as much exposure time on my target as possible. Stacking several images together can increase the amount of signal collected while reducing noise by canceling out its random output. For more information about the concept of signal-to-noise ratio, Craig Stark explains it better than I ever could.

astrophotography telescope

My telescope with the Canon EOS Rebel T3i attached

Overcoming light polluted skies

I’ve got lots of experience here, as the majority of my deep sky astrophotography is done from home. In theory, a light pollution filter will let you shoot longer exposure times before being blown out on the histogram, but this comes at a price. The signal (light) is often weak, and the natural color emitted from the stars has been altered. For both of these trade-offs, capturing more integrated exposure time can be a huge help.

A popular and effective method of overcoming the light polluted skies of an urban backyard is to use a monochrome camera equipped with narrowband filters. This has the power to aggressively ignore artificial light and isolate the light associated with specific gases in objects in space. But what about those shooting with a DSLR camera?

A color camera like a DSLR uses an internal Bayer matrix to create full-color images in a single shot. This convenience comes at the expense of a much weaker signal when compared to a monochrome CCD or CMOS camera. To offset this challenge, I like to use camera filters that help me isolate the light I want to collect.

camera filter

I use a clip-in light pollution with my Canon DSLR (Skytech CLS-CCD)

Shoot During New Moon

Although narrowband filters have allowed me to take photos during all moon phases, the new moon phase is a special time for amateur astrophotographers. The days surrounding the new moon phase mean that I can finally capture true color images of my subject with more natural colors.

Believe it or not, the bright glow of Earth’s natural satellite produces enough skyglow to really reduce contrast in your deep sky images. Even a narrowband filter won’t help if your target is sitting too close to a bright full moon.

Light pollution filters such as the Astronomik CLS and IDAS LPS D-1 help to reduce moonglow, but for the absolute best data on a deep sky target, the new moon phase is best. If you’re planning on shooting unfiltered, this is definitely when you want to try it.

Shooting Without a Light Pollution Filter

It’s also worth noting, that for certain targets, an incredible image can be captured without using a filter at all. Don’t believe me? Have a look at this photo of the Andromeda Galaxy posted by Jon Rista on Astrobin. The image was created by stacking 174 x 150-second subs at a modest ISO 400 under light polluted skies. Inspired? I was too.

I plan to capture the Pleiades from my backyard again soon using only the required UV/IR (luminance) filter with my modified DSLR. This target does not emit light that a narrowband filter can isolate, as it is a reflection nebula. Another target that would be a great test subject for this technique is M31, as seen in Jon’s image above.

Update:

I captured the Pleiades star cluster using a new light pollution filter, the Optolong L-Pro. This is a multi-bandpass filter the does a great job of preserving the natural star colors in my images from the city. Have a look at sample image comparing an unfiltered image and one using the Optolong L-Pro:

filter comparison

My full review of this broadband astrophotography filter includes an image of the Pleiades star cluster captured with a stock Canon 5D Mk II camera.

Optolong L-Pro Filter Review – An Urban Broadband Astrophotography Filter

Selecting a Target

I no longer go into my astrophotography projects blind. In the early days, I would set up my telescope and astrophotography gear and think to myself “what will I shoot tonight?”. As carefree and exciting as those nights were, they also included a lot of wasted clear sky time looking at a computer screen while the night passed me by.

These days, I prefer to take a much more organized approach to deep sky astrophotography as my time is limited, and clear nights are rare. I find it best to double down on deep sky targets that not only compliment my equipment but maximize exposure time and increase the chances of “completing” a final image.

astrophotography book

I often refer to my “The 100 Best Astrophotography Targets” book for inspiration (On Amazon)

My decision-making process involves answering the following questions:

  • Have I photographed this target before?
  • Is the target in the early, mid or late position for the season?
  • Is it a good fit for the focal length of my telescope?
  • Does this object require narrowband data to properly showcase?
  • Will it turn out well in color using a DSLR camera?

As an example of a target’s position relating to the season – you wouldn’t want to start a new astrophotography project on a DSO that is on its way out and fading deeper and deeper into the Western twilight each night. Right now, Orion (winter target) is in the early season stages, while objects like the Crescent Nebula (Summer target) are on their way out.

It’s beneficial to select a deep sky target that will get as high from the horizon as possible. This will, of course, vary by your location but aim to collect light on subjects that are in their optimal position for the time of year. Your backyard window of the sky and potential obstructions in your yard will also factor into your selection.

deep sky imaging setup

My deep sky imaging setup in the backyard

Despite having several previous iterations of IC 1848 on my hard drive, The Soul Nebula checked off the most boxes and won the battle for option selection. It currently sits in an opportunistic area of the night sky to collect a serious amount of exposure time this month.

This will be a great opportunity to improve my broadband color data collected on the Soul Nebula to improve upon my image from last year.

Why I’m using a DSLR

With a number of dedicated astronomy cameras and cooled CMOS cameras in my possession, why would I opt for using an old DSLR camera instead of impressive astronomy camera like the QHY128C? (I’m working on it)

For starters, I wanted to produce another example image using the Zenithstar 73 APO with a DSLR. In my last video I shared images of the heart Nebula and Butterfly Nebula in narrowband Ha – but this time I’ll collect images in good old full color. My results on the Soul Nebula should give you a good idea of what to expect with a crop sensor DSLR camera like my Canon T3i or similar models.

A telescope like the Zenithstar 73 is a logical telescope choice for deep sky beginners just entering the hobby, and many of those people will be using a DSLR. It’s easy to get carried away in my posts and videos and skip over the basic information beginners are looking for, so I’ll try my best to scale back when the situation calls for it.

connecting a DSLR to a telescope

My DSLR attached to the Flat 73 Field Flattener and Zenithstar 73 Telescope

Camera Settings for a Washed Out Sky

From my bright sky here in the city, I’ll use 3-minute exposures at ISO 800 to capture the Soul Nebula. This is a rather conservative approach, which may have you wondering why I’m not shooting longer subs. A typical DSLR light frame under moderately light polluted skies would normally be 5 minutes at ISO 1600, but it’s a hot a humid night, and those settings would absolutely cook my sensor.

In these conditions, there is little value in collecting images longer than 3-minutes. As the noise increases significantly, the signal sees very little improvement. You are much better off capturing several shorter images over time. (My camera sensor hit 32°!) Even at 180-seconds, I am capturing A LOT of skyglow that will have to be dealt with in post-processing.

Camera Settings in the City

  • Mode: Manual
  • Format: RAW
  • ISO: 800
  • White Balance: Auto
  • Exposure: 180-seconds (3 minutes)

*Note without using a light pollution filter, this exposure time would be cut in half.

light frames

Previewing my 3-minute light frames in Adobe Bridge before stacking

Focal Ratio is Important

The Zenithstar 73 APO is fast. It’s fixed f-ratio of F/5.9 can collect light faster than most of the refractor telescopes I’ve used in the past (Including my Explore Scientific 102). This gives my images a much-needed boost in signal for each short 180-second sub. A lower focal ratio allows more photons to hit your camera sensor in a single exposure, which makes a big difference in terms on SNR.

Naturally, the aggressiveness of the filter (in this case a SkyTech CLS CCD) in front of the camera sensor changes how much signal I can record in a single exposure.

White Balance

I’ll leave the cameras white balance set to auto, as I see no benefits in adjusting this setting at this stage. Because I am shooting the images in RAW format, I can manually adjust the white balance to whichever temperature I want in post-processing. With that being said, there have been some interesting discussions on the topic of the benefits of using a custom white-balance for astrophotography in heavy light pollution.

Capture Software

The images are being captured using APT (Astro Photography Tool) on my new laptop computer. Autoguiding through PHD2 guiding and the Altair GPCAM + 50mm guide scope mean that each image contains sharp stars each and every time. If you’re looking for an affordable autoguiding package to upgrade your kit, have a look at the Starfield autoguiding package offered from Ontario Telescope.

The images are dithered between each frame to further reduce noise – which can easily be switched on within the gear tab of APT. To learn more about the process of data acquisition including the use of support files (dark frames, flat frames), please visit the get started page.

Light Pollution Filter for Canon DSLR’s

For broadband spectrum targets like galaxies (and many reflection nebulae), a light pollution filter is less effective. However, for an emission nebula like the Soul Nebula, isolating the light emitted in the H-Alpha and OIII wavelengths can make a big difference.

Longtime followers of the blog will remember the SkyTech CLS-CCD filter I reviewed last year. Time and time again, this filter has impressed me with its ability to produce impressive color images using my DSLR camera in heavy light pollution.

Light pollution filter for Canon

The SkyTech CLS-CCD clip-in light pollution filter for modified DSLR cameras

This filter has been my go-to choice when it comes to capturing true-color broadband images from home. It does a great job of creating contrast between my target and a washed out city sky. The only downside is that it also alters the color balance of my image and paints the surrounding stars with a red cast.

Later this month, I’ll be testing out an Optolong L-Pro filter with my DSLR camera, which is said to be “a true 5 bandpass filter”. This multi-bandpass filter is less aggressive than the CLS-CCD and should help with my color balance issues. My hope is that this filter is a much needed middle ground between shooting with the CLS-CCD filter and unfiltered. I expect my exposures to be shorter using this filter here in the city.

Optolong L Pro FIlter

The Optolong L Pro Filter is 5 Bandpass Light Pollution Suppression Filter

For Stock Canon DSLR cameras

Owners of stock (non-modified) DSLRs will want to get a standard CLS (city light suppression) filter such as the Astronomik CLS clip-in filter without the unnecessary UV/IR cut filter. If you’re unfamiliar with what it means to modify a DSLR for astrophotography, have a look at this page where I cover this aspect of astrophotography cameras and more.

The Soul Nebula in Cassiopeia

With an apparent size of 150′ × 75′, the Soul Nebula is a fantastic deep sky astrophotography target for a DSLR camera and compact wide field refractor telescope. It also rises above the roof of my house just as nightfall sets in, which is perfect timing in terms of maximizing my imaging time.

It’s a beautiful emission nebula with several embedded open star clusters. It emits a strong amount of light in the hydrogen-alpha wavelength, which makes adding images captured through an Ha filter beneficial.

star map of the Soul Nebula

Where to find the Soul Nebula

If you’ve been following my backyard activity via the email newsletter, you’ll know that I’ve been using another exquisite compact refractor. This time, it’s the William Optics Zenithstar 73 APO, and my resulting image should give you a good idea of what you can expect from this affordable doublet from an urban sky.

My Telescope

The William Optics Zenithstar 73 APO is a compact F/5.9 doublet apochromatic refractor with an impressive entourage of accessories to get you up and running. The Flat 73 1:1 field flattener is an essential upgrade if you plan on imaging with a full frame camera.

This telescope has a focal length of 430mm, which creates an extremely wide field of view. This means that it is well suited for large nebula targets like the Soul Nebula or Heart Nebula in Cassiopeia, but less effective on smaller targets such as galaxies.

The package I have includes a guide scope rings and a matching 50mm guide scope with gold accents. Using the M48 Canon adapter, I thread my Canon T3i to the Flat 73 for incredible wide field exposures of my target of choice. Owners of DSLR cameras looking for an easy entry point into deep sky astrophotography should look no further than the Zenithstar 73 APO.

DSLR camera and telescope

The William Optics Zenithstar 73 APO is available at Ontario Telescope

It’s incredibly compact and manageable to use. If you’ve ever fought with balancing a large reflector telescope on a mount, you’ll really appreciate a compact telescope like the Z73. There is less stress on the mount, meaning can effortlessly track your target, even if the overall payload balance isn’t perfect.

One of my favorite features is a simple yet ingenious design touch. They’ve built a Bahtinov focus mask into the lens cap.

Focusing the image with the Z73

The diffraction spikes focus mask is a convenient feature you’ll find in all new William Optics refractors. To focus with my DSLR, I simply find a bright star in the live view screen with the focus mask attached. Because the material is made from optical acrylic rather than metal, this mask provides 92% light transmission.

DSLR camera sensors are not as sensitive as most dedicated astronomy cameras. So the added light transmission from this mask really comes in handy when focusing your star using the rather dim 10X live view mode.  You’re presented with nice long diffraction spikes to really nail down your optimal focus position.

focus bahtinov mask

The built-in Star Diffraction Spikes Bahtinov Mask on the Z73

You’ll need a telescope mount that’s capable of handling a refractor telescope, but its small size means that beginner level astrophotography mounts such as the Orion Sirius EQ-G, Celestron AVX or Sky-Watcher HEQ5 will perform well with it.

My Telescope Mount

The Sky-Watcher HEQ5 SynScan pro has been called in for duty to capture sub guided 3-minute subs on the soul. It’s more than capable of accurately tracking this gorgeous nebula with the 5.5-lb Zenithstar 73 APO attached. I purchased this mount from a Canadian astronomy classified website several years ago, and it’s been working flawlessly ever since.

It allows me to set up quickly and easily Polar Align the mount within minutes. I still use the SynScan hand controller to star align the mount and slew to my target, although most prefer to advance to using the EQMOD software to control this mount from their PC.

tracking telescope mount

My Sky-Watcher HEQ5 SynScan Pro Telescope Mount

Speaking of Sky-Watcher, I am not done with the Esprit 100 ED just yet, not even close. With the departure of the iOptron CEM60 mount a few weeks ago, I had to find a solution to carry my heavier telescopes.

I am excited to announce the arrival of a brand new Sky-Watcher EQ6-R GoTo Mount as of this week. The built-in illuminated finder scope, SynScan hand controller and snow-white finish will all feel very familiar – except there’s no rust on the counterweight!

I’ll have much more information to share about this soon.

Conclusion and Results

Mother nature doesn’t care what the calendar says, because Tuesday night’s imaging session was a nearly record-setting 31 degrees in Southern Ontario. Unfortunately, this increased the amount of noise in my images of the Soul Nebula (Sensor at 32°), but luckily my total integration time helped to improve the SNR.

Shooting with an uncooled DSLR is not ideal on hot nights like this – but nights like this are numbered, and soon I’ll be complaining about numb fingers, not camera noise.

The following image combines my latest data with images of the same target collected last year. All of the images were captured using a modified Canon EOS Rebel T3i camera and SkyTech CLS-CCD filter from the backyard.  The only difference in acquisition details between 2017 and 2018 was the use of a Meade 70mm Quadruplet Astrograph in 2017.

Narrowband Hydrogen-alpha data was added as a luminance layer to this image using the HaRGB method in Adobe Photoshop. This is a powerful way to boost signal in an emission nebula captured under heavily light polluted skies. For these images, an Astronomik 12nm ha clip-in ha filter was placed inside of the camera.

The Soul Nebula

IC 1348 – The Soul Nebula captured from Bortle Class 8 Skies with a DSLR Camera

The images captured this week on the Soul Nebula using the Z73 totaled 3 hours and 15 minutes (65 frames). As expected, the final still contained a fair amount of noise, even with the aid of dark frames and over 3 hours of exposure time. Doubling my integration time would certainly help.

The images were registered and stacked in DeepSkyStacker, with the final image processing done in Adobe Photoshop. The Astronomy Tools Action set contains many useful one-click actions that I regularly use on images like this taken from the backyard. (You can find a list of the software I use to process my images on the resources page)

Darker skies have a clear advantage when it comes to capturing deep sky astrophotography images. But with enough exposure time and the right image processing strategy, you can capture breathtaking images from your own backyard – no matter how light-polluted it may be.

Equipment Mentioned in this Post

Sky-Watcher HEQ SynScan Pro GoTo Mount (Now the AZ-EQ5)

William Optics Zenithstar 73 Refractor Telescope

William Optics Flat 73 Field Flattener

Canon EOS Rebel T3i (full spectrum modification)

SkyTech CLS-CCD Clip-in filter for Canon EOS

Astronomik 12nm Ha Clip-in filter for Canon EOS

AmazonBasics USB 2.0 A-Male to Mini-B (6 feet)

Replacement AC Adapter (Battery Replacement) for Canon T3i

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Astrophotography in the City

|Backyard|1 Comment

Saturday Night Under the Stars

Astrophotography in the City

Last weekend I posted a new video to the my YouTube channel titled DSLR Astrophotography – A Night in the Backyard with my Camera. It is now Early-April, and we are in what amateur astrophotographers call “Galaxy Season”, as we transition from the Winter Constellations like Orion and Taurus, to the Summer Milky Way objects.  In between, there are some fantastic deep-sky objects to observe in the Spring Constellations Leo, Coma Berenices and Bootes.

The forecast called for clear skies on that crisp, cold Saturday night in Southern Ontario, and I was ready to image some deep-sky objects with my camera and telescope.  After a late dinner, it was a race against the clock to photograph my first subject of the evening, the Waxing Crescent Moon. If you want to jump straight to the video, you can find it at the bottom of this post.

Live-View DSLR Through a Telescope

Using the Canon 70D’s live view screen for telescope observing

Crescent Moon Astrophotography

 

I barely had time to get the beautiful Waxing Crescent moon into my telescope’s eyepiece before it became obscured by the surrounding trees in my neighborhood!  I shot a live-view video of the moon (with Earthshine visible) with my Canon EOS 70D DSLR through the telescope.  This may be of interest to anyone wondering what the view is like through an 80mm refractor telescope.  You need an adapter to attach the camera to the telescope, which you can buy online here.

After I focused the Moon and experimented with different ISO settings and exposure lengths, I snapped a couple of shots before moving on with the rest of my night.  You can have a look at the equipment I use for astrophotography here.

 

Earthshine Moon

The sky from my backyard

Next, I wanted to provide some examples of the dark-sky quality from my backyard.  Living in the central part of town has its advantages, but dark skies are not one of them!  I experience heavy light pollution from all directions.  This makes using a light-pollution filter on my camera necessary for long exposures.  Currently, I use the IDAS LPS clip-in filter on my Canon Rebel Xsi DSLR.  This allows to me to capture exposures of up to 5 minutes from my backyard.

 

Astrophotography in the City

The night sky from my backyard on April 9, 2016

 

The Big Dipper Asterism

Looking towards the Big Dipper in Ursa Major

Deep-Sky Target: Edge-On Spiral Galaxy in Coma Berenices

NGC 4565 – The Needle Galaxy

Once the moon had set, I promptly prepared my deep-sky astrophotography rig for a night’s worth of photons on my photography subject.  I settled on NGC 4565 – The Needle Galaxy because of it’s size, magnitude, and current location in our night sky.  The Needle Galaxy is an edge-on spiral galaxy that resides about 30-50 million lights years from Earth.  This handsome galaxy is the current photo in my 2016 RASC Observer’s Calendar hanging in my office at work, perhaps that is what gave me the idea!

Astrophotography in the City - Needle Galaxy from my backyard

NGC 4565 – The Needle Galaxy

Photographed on: April 9/10, 2016

Total Exposure Time: 54 Minutes (18 x 3 Min. Subs @ ISO 1600)
Mount: Sky-Watcher HEQ-5 Pro
Camera: Canon 450D (modified)
Telescope: Explore Scientific ED80 Triplet Apo

Guided with PHD Guiding
Stacked in Deep Sky Stacker
Processed in Adobe Photoshop CC

This interesting NGC object shows up rather small in my 80mm telescope, as many galaxies do.  A larger telescope with a focal length of 1000mm or more would be a better choice for this DSO.  I also had a bit of a challenge evening out the background colour of this image.  Flat frames would have made this issue much easier to deal with in post-processing.  With just under an hour of exposure time, it is safe to say that I will need to add more time to this image to bring out the colour and detail.


AstroBackyard on Youtube

I am completely blown away with the response to my YouTube Channel has received.  Thank you to everyone who has subscribed, I look forward to many new astrophotography videos in the future!

Beginner Advice:

What’s the best telescope for astrophotography?

Which camera do you recommend for beginners?

Astrophotography Settings and Tips

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M33 Galaxy – The Triangulum Galaxy

|Galaxies|0 Comments
M33 Galaxy

M33 – The Triangulum Galaxy

The Triangulum Galaxy

The M33 Galaxy is the third-largest galaxy in the local-group of galaxies, behind the Milky Way and Andromeda.  It’s large size from our vantage point makes my wide-field astrophotography 80mm telescope a great choice for imaging this target. Despite it’s size, the Triangulum Galaxy appears much dimmer than M31 – The Andromeda galaxy.  If you are new to astrophotography, chances are that the Triangulum Galaxy is one of the first few galaxy names you have learned.

M33 Galaxy Photo Details:

Telescope: Explore Scientific ED80 with WO Flat III 0.8x FR/FF
Mount: Skywatcher HEQ5 Pro Synscan
Guiding: Meade DSI Pro II and PHD Guiding
Guide Scope: Orion Mini 50mm
Camera: Canon EOS 450D (Modified)
ISO: 800
Total Exposure: 7 Hours (84 x 300 seconds)
Processing Software: Deep Sky Stacker, Photoshop CC
Support Files: 20 darks, 20 flats, 20 bias

Target Acquired – Messier 33

I have managed to image the M33 Galaxy from my backyard for multiple nights over the course of nearly a week. I can’t remember the last time we have had such a long stretch of clear night skies in the Niagara region. Mind you, these clear nights occurred during weekdays, and I have to be up early for work (and to walk the dog) early each morning. Needless to say, I haven’t been getting much sleep lately.  Luckily my astrophotography equipment can be set up and ready for imaging in about 30 minutes. This includes polar alignment, calibration, focus and guiding.  

M33 Galaxy - Astrophotography

My Telescope pointed at the M33 Galaxy

But first, the Elephant’s Trunk

My first imaging session was on the night of September 16th. Smack-dab in the middle of the work week. I didn’t originally intend to shoot the M33 galaxy that night, I started with IC 1396. The Elephant’s Trunk nebula is a concentration of interstellar gas and dust within IC 1396, located in the constellation Cepheus. You can view the results of this project below.

This area of the night sky is in a perfect spot for imaging at this time of year from my location, almost directly overhead. I captured 38 frames on this DSO on Wednesday night. The subs were 4 minutes each using ISO 800 on my aging modified Canon Xsi.

IC 1396 – Elephant’s Trunk Nebula

Elephant's Trunk Nebula

IC 1396 – Elephant’s Trunk Nebula – A tad noisy!

IC 1396 – Astrophotography Image Details

Telescope: Explore Scientific ED80 with WO Flat III 0.8x FR/FF
Mount: Skywatcher HEQ5 Pro Synscan
Guiding: Meade DSI Pro II and PHD Guiding
Guide Scope: Orion Mini 50mm
Camera: Canon EOS 450D (Modified)
ISO: 800
Total Exposure: 2 Hours, 24 Minutes (36 x 240 seconds)
Processing Software: Deep Sky Stacker, Photoshop CC
Support Files: 15 dark frames

The Elephant’s Trunk nebula can be seen in the top center-right of the photo above. It is a dark patch with a bright, sinuous rim. The rim is the surface of a dense cloud that is being illuminated and ionized by a very bright, massive star. Faint objects like this are difficult to image from light-polluted skies in the city. I found myself battling with horrible gradients and noise when processing this image. I will likely add more time to the Elephant’s Trunk Nebula during the weeks that surround the new moon in October. Another 4 hours should help me pull out more detail with less noise.

Canon 450D attached to my telescope

Canon Xsi 450D for astrophotography – attached to my telescope with the William Optics 0.8 FF

On to the M33 Galaxy…

After achieving a steady graph in PHD guiding, and a tight-focus on my reference star (Alderamin) I set BackyardEOS to take 50 frames, and I headed to bed.  I set my alarm for 2:00am, and managed to stumble back out to the patio to check on my results.  The Elephant’s trunk nebula was too far west, and my telescope would soon by aiming directly at my garage!  Because the sky was still crisp and clear, I figured I would add some time a second object for the night.  I imaged the M33 Galaxy back in 2012, but that was before I self-modded my 450D for astrophotography.  The Triangulum Galaxy contains some beautiful pink nebulosity within it that I knew I could now capture.

The following 2 nights of the week were also clear, and I took full advantage. This time, I shelved my plans for the Elephant’s trunk, and focused all of my efforts on Messier 33. I captured an impressive 49 subs the following night at 5 minutes each, and then I added another 17 light frames the night after that!

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M33 Galaxy

M33 – The Triangulum Galaxy

My total number of frames on this object was now over 100! That’s a lot of imaging in one week. All that was left now was to stack and process all of the data acquired. I set Deep sky stacker to use “the best 90% of frames” to register and stack, which resulted in a final stack of 84 images total, or exactly 7 hours. I even had success with my creation of flat and bias frames. I shot the bias frames through the telescope with the lens cap on, at the fastest shutter speed my camera allows (1/4000 of a second). The flat frames were created by shooting through the telescope, pointed at the early morning blue sky. These were shot with the camera in Av mode. I shot separate bias and flat frames for each night, except the first. Only dark frames were used for that imaging session.

Processing a photo with 7 hours worth of data is quite enjoyable.  There is less noise, and more detail than I am used to.  As with all of my astrophotography images, I am sure I will re-process my photo of Messier 33 several times until I feel like I have done the galaxy justice. Everyone has their own taste, and at the end of the day, you have to be happy with it.

BackyardEOS 3.1

I finally purchased a copy of BackyardEOS 3.1 Classic Edition. My trial period has ended, and I am very happy with the software. The focus and framing tab, dithering control, and file organization features are my favourite, and make me wish I had upgraded to this software a lot sooner. I always had a hard time getting accurate focus using the live-view function of my DSLR. The focusing function built-in to BackyardEOS allow you to view a digital readout of the star size in real-time as you focus your telescope. The lower number you see on-screen, the better your focus! The filename for each sub lists the ISO, object name, exposure time, date and even the temperature! This is extremely handy when stacking a large number of frames from multiple nights.

BackyardEOS

Screenshot of the BackyardEOS 3.1 Software

I would love to hear what you think of my results for this galaxy image.  You can also follow me on twitter to see more of the “behind-the-scenes” stuff from the backyard. As always, if you have any questions about the equipment I used, or my processing techniques, please leave a comment below.  Thank you so much for visiting my website.

Backyard Astrophotography

Another night under the stars in the backyard

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