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Forgotten Light Frames

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While digging though some old folders on Adobe Bridge, I stumbled across some unprocessed, 300 second light frames of the Flaming Star Nebula from November 2013!  When you are desperate to get out and image a new target, this is like hitting gold.  

I was originally looking for my raw files of the Pacman Nebula, which I feel is in desperate need a new process. (Those stars look pretty rough)  I found a folder labelled “Flaming Star – 5 Min Lights”.  I never processed this image!  The Flaming Star Nebula is a colorful collection of glowing gas and dust lit up by the bright star AE Aurigae. 

The tough part about this process will be the limited exposure time.  1 hour of data is really not ideal for a quality astrophotography image.  I find that out the hard way below:

IC 405 – The Flaming Star Nebula

IC 405 - Flaming Star Nebula

Photo Details

Photographed on: November 29, 2013

Telescope: Explore Scientific ED80 with WO Flat III 0.8x FR/FF
Guiding: Meade DSI Pro II and PHD Guiding
Guide Scope: Orion Mini 50mm
Camera: Canon EOS 450D (Stock)
ISO: 1600
Exposure: 1 hour (12 x 300s)
Processing Software: Deep Sky Stacker, Photoshop CC
Support Files: 15 darks

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

This image was acquired using Canon EOS Utilities, and not BackyardEOS as I use now.  This was photo was also shot before I modified my Canon 450D for astrophotography.

Now you might be thinking “how could you spend hours imaging a nebula and forget to process it?”  It’s simple – life is busy!  I likely had a busy week following the the imaging session, and began I new session before I even looked at the precious data collected on that cold November night.  I don’t see any dark frames to support the image.  

This may have been another reason I held off.  I bet that I wanted to take 5-minute darks of the same temperature before stacking, but never got around to it.  This could be a problem.

But first, let’s get this cleared up

This is budget Astrophotography.  Most of my gear was purchased used from online forums and astronomy classifieds.  The total value of the equipment used to photograph this nebula was purchased for under $3,000.  It’s not top-of-the line gear by any stretch of the imagination.  My astrophotography image processing skills were self-taught.  I am no scientist, that’s for sure. Just like you, I have a strong desire to capture beautiful images of the night sky.  I always appreciate constructive criticism, and enjoy helping others learn through my mistakes.

Stacking without Dark Frames?

First of all, I’ll have to use dark frames from a different night to stack with the Flaming Star light frames.  This means that it is very important to match the temperature of my light frames from that night of imaging.

I have done a poor job of creating a master dark library, so finding matching dark’s may be tough.  I usually try to record the temperature of my dark frames in the file folder, for this very situation.  There are external software applications available that can help create a dark frame library, such as Dark Library.  

I remember using this years ago, but their website appears to be down right now.  I will use the 5 minute dark frames from my Pacman Nebula image taken earlier that month, labelled 4 degrees.

Another option is to just stack the light frames without any dark’s.  I’ll try both and compare the two.

Here is the version stacked with no dark frames:

Deep Sky Stacker with No Darks

Here is the version using dark frames from a previous night:

Deep Sky Stacker with Darks

As you can see, stacking with the dark frames produced a better result.  Even though the temperature of dark frames did not match perfectly, the dark frames removed some of the dead pixels and noise from the image.  Notice the red streak of dead pixels on the “no-darks” version.  All of these imperfections would become intensified after processing!  

I performed a few basic edits to the examples above to have a better look at the differences. (Levels, Gradient Xterminator, and Curves)  Now that we have registered and stacked our 1 hour’s worth of data, let’s start stretching the data in Photoshop.

How to take proper Dark Frames for Deep Sky Stacker

The answer to this and more in the FAQ section

Processing the Image in Photoshop

If you have followed any of my astrophotography tutorials on my website, or video tutorials on YouTube, you already know the basics of my processing workflow.  This process has evolved over the years as I learn new tricks.  However, processing the Flaming Star Nebula was particularly tough because of the limited exposure time on the subject.  

Add in the fact that this nebula is quite faint, with many bright stars surrounding it, and you’ve got an astrophotography challenge for even the most experienced astrophotographer.

 

Quick Astrophotography Tip

Try to frame your deep-sky object in an interesting way.  Include nearby star clusters, nebulae or galaxies.  For inspiration, search for your target on APOD, and see how the professionals have framed the object.  This may spark your creativity to photograph an existing target in a different way.

HLVG – Green Noise Remover

The entire image had a noticeable green cast over it, perhaps because of the extreme amount of noise, or the miss-matched dark frames.  I ran Deep Sky Colors HLVG on medium, which helped a lot.  HLVG was created by Rogelio Bernal Andreo of RBA Premium Astrophotography. 

It is a chromatic noise reduction tool that attempts to remove green noise and the green casts this noise may cause in your astrophotography image.  It is based on PixInsight’s SCNR Average Neutral algorithm.  If you don’t already have this useful filter for Photoshop, I highly recommend it, it’s free!  You can download the plugin here:

Hasta La Vista, Green!

HLVG Filter for astrophotography

Results and Thoughts

I must admit, this post became a bit of a nightmare.  I began to document my processing steps one by one, taking screenshots of progress along the way.  I wanted to provide a detailed tutorial of how I turned this forgotten data into a masterpiece, despite having no associated dark frames, and only an hour’s worth of exposure time.  As I experimented using different methods of noise reduction, and various orders of operations, I became very discouraged with my final image results.  

I spent hours taking different roads with all of my trusted astrophotography tools at my disposal, and the results continued to be unimpressive.  By adjusting the curves enough to show any substantial detail on the nebula, I introduced a frightening amount of noise into the background space.  No amount of noise reduction could remove it, without turning the entire image into a blurry mess.

I just couldn’t bring myself to post a tutorial with the end result turning out like it did.  So I scrapped the idea, and settled for a forgettable image of the Flaming Star Nebula.  Surely this gorgeous nebula that spans 5 light years across deserves more than that.

Astrophotography Processing Tutorial

My unused processing tutorial screenshots

At the end of the day:

No amount of processing can make up for lack of exposure time!

I guess you could say I was doomed from the start.  I am not going to spend any more time on this image until I am able to capture at least another 2 hours of data on it.  I hope you can learn from my experiences in astrophotography, in both victories and failures.  But I guess that’s why you’re here ūüôā  Please follow AstroBackyard on Facebook for the latest updates.

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Astrophotography Video Tutorial

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Astrophotography Video Tutorial

Astrophotography Video Tutorial

In my first ever astrophotography video tutorial, I take a crack at the Rosette Nebula using data collected in February 2014. I have plans of shooting a video about light frame acquisition in the future, but this one is about what happens after you have already captured your data.  This astrophotography video tutorial may be useful to anyone who has questions about the stacking process, and processing the created .TIF file in Adobe Photoshop.

I must admit, I learned a lot about how I could improve upon these videos in future during the process.  Putting together an online tutorial video using a particular piece of software is harder than it looks!  Nevertheless, I believe new astro-imagers will find some useful information in my video.

My astrophotography processing techniques

In the video, I discuss the importance of organizing and inspecting your raw image files before you dive-in to Deep Sky Stacker. The application I find most useful for this stage is Adobe Bridge.  I subscribe to the Adobe Creative Suite that includes all of the Adobe applications, so using Bridge as my default image viewer was a no-brainer.  I know that Adobe Lightroom is another popular choice for this purpose as well. Alternative methods for viewing RAW image files on your PC are Faststone Image Viewer, Canon EOS Utilities and installing the proper codec on your particular version of Windows to preview the files.  I have used Faststone Image Viewer and Canon EOS Utilities, but I have not tried the Windows Codec option.


Video Summary

Using Deep Sky Stacker, I register and stack over 2 hours worth of 3.5 minute light frames I captured of the Rosette Nebula with my Canon Xsi and ED80 Telescope. As always, dark frames are subtracted from the final image to produce a final image with a higher signal-to-noise ratio.  I then locate and open the 32 bit Autosave.tif file into Adobe Photoshop CC for further processing using helpful astrophotography plugins including Gradient Xterminator and the Astronomy Tools Action Set. The order of the actions I make when processing an astrophoto from the RAW image files to the final result are as follows:

  1.  Stack and register light and dark frames in DSS
  2.  Open Autosave.tif file in Adobe Photoshop
  3.  Slight Image Crop to remove stacking artifacts
  4.  Removal of gradient and vignetting via Gradient Xterminator
  5.  Levels Adjustment
  6.  Convert to 16-bit/channel image
  7.  Curves Adjustment
  8.  Astronomy Tools Action > Local Contrast Enhancement
  9.  Astronomy Tools Action > Enhance DSO and Reduce Stars
  10.  Astronomy Tools Action > Increase Star Colour
  11.  Astronomy Tools Action > Make Stars Smaller
  12.  Balance neutral background sky colour
  13.  Increase Saturation
  14.  Final Curves Tweaks

The Learning Curve

Up until this point, I’ve been the student, not the teacher. ¬†I want to show beginners how I process my astrophotography images,¬†but my presentation skills leave much to be desired. I have always been an artist at heart, so my methods may seem unorganized and random to the general public. ¬†I am more likely to “trust my eyes” rather than a set of¬†numbers and graphs, although I recognize their value. ¬†I feel that through the process of teaching¬†others how to capture and edit photographs of the night sky, I will gain a deeper appreciation and knowledge of the hobby for myself. ¬†Thank you to everyone who has subscribed to my YouTube channel so far. ¬†I am just getting started.

 

AstroBackyard on YouTube

 

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M33 Galaxy – The Triangulum Galaxy

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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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