First attempt using an astro-specific stacking app

[rcreamer]

Here are the first astro images I've stacked with a non-Photoshop stacking program: Astro Pixel Processor (on MacOS).

I'm having to grapple with steep learning curves: 1) the stacking app itself, and 2) best exposure settings.

Both images were taken with an A7R5 and the 70-200mm ii Sony tele on a Sky Watcher GTi star tracker. A Bahtinov mask was used for focusing.

[Update: I'm including a photo showing what it looks like when focusing using the Bahtinov mask. When you point the camera with the mask over the lens at a bright star, you see a diffraction pattern with two criss-crossing lines along with a 3rd line which moves roughly up and down when you adjust the focus ring. When the moving line exactly bisects the two criss-crossing lines, the lens is theoretically in focus. This tool can also be used for regular low-light landscape work with distant lights, btw. Some Bahtinov masks are too coarse to work with wide angle lenses, fyi. The one I got has lines that are fine enough to work with my 14mm Sony prime. I got mine at Johannes Scientific for $35.]

I still have a lot to learn and also need more hours of integration time

At least I'm starting to see star colors vs my earlier attempts.

Here are the exposure details for the two attached images. (I'm not taking any calibration frames yet.)

_____

M31 - The Galaxy in Andromeda

(40) 120-second exposures at ISO 800, 200mm lens, f2.8

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The Pleiades Star Cluster

(70) 120-second exposures at ISO 800, 200mm lens, f2.8

• ILCE-7RM5
• FE 70-200mm F2.8 GM OSS II
• 200.0 mm
• ƒ/2.8
• 2.5 sec
• ISO 8000

• notAvailable
• 8399 sec

• notAvailable
• 4680 sec

 

[THXGEEK]

Those are really good!

Are you near any major sources of light pollution (i.e. airports, big cities, etc)? I am in suburban Northern Virginia (near Dulles airport) and the sky glow here is awful (Bortle 7.5). I'd have to drive for an hour just to find decent dark skies....

 

[THXGEEK]

Light Pollution Map.

 

[rcreamer]

Those are really good!

Are you near any major sources of light pollution (i.e. airports, big cities, etc)? I am in suburban Northern Virginia (near Dulles airport) and the sky glow here is awful (Bortle 7.5). I'd have to drive for an hour just to find decent dark skies....

Thanks. I live in a Bortle 4.5-5.0 area (California foothills). These were taken from my living room deck There's actually a lot of sky glow in the north and northeast but these targets were south of this a bit. I can get rid of a lot of that in LR by lowering the Blacks, but you have to try to keep it real. Since I can only experiment/practice a few days each moon cycle, it's going to take me months to get better and try new techniques. I can drive to Yosemite in 2 hours where the skies are pretty dark and hope to give that a try soon. I got a Jackery Explorer 300 v2 power station to power my star tracker and a7r5.

 

[Richard A]

Great stuff! Well done.

 

[rcreamer]

Light Pollution Map.

Thanks, I didn't notice this before. This is pretty cool and fairly accurate. Thanks for sharing!

 

[DavidN]

Hi Richard, Very good first attempts. I know all about the steep learning curve. Try stacking and processing in StackingWizard and AstroWizard. Both are free and really easy to use + you can use Sony RAW files straight into StackingWizard. Luke has some good tutorials on YouTube. You'll find you are a bit limited for targets with a 200mm lens - M31 is a nice exception. If you feel you want to progress, have a look around for a small refractor telescope as this would also give you the option to use narrowband filters which are essential for nebula but as with all hobbies, it starts to get expensive!

 

[rcreamer]

Hi Richard, Very good first attempts. I know all about the steep learning curve. Try stacking and processing in StackingWizard and AstroWizard. Both are free and really easy to use + you can use Sony RAW files straight into StackingWizard. Luke has some good tutorials on YouTube. You'll find you are a bit limited for targets with a 200mm lens - M31 is a nice exception. If you feel you want to progress, have a look around for a small refractor telescope as this would also give you the option to use narrowband filters which are essential for nebula but as with all hobbies, it starts to get expensive!

Thank you, David I will certainly try your suggested stacking software (I bookmarked them when you mentioned them in your earlier post). I already had a trial license for Astro Pixel Processor, so will finish evaluating it before I move on to your suggestions and others perhaps. It turns out that APP is pretty easy to use for lights-only Sony raw images. Just: 1) Load, 2) Integrate, 3) Save to TIFF (reduce the Background slider before exporting so result isn't too over-stretched). I also have dozens of refractors bookmarked and added yours to the list last week. I'm going to be moving to a more light-polluted area soon and don't want to invest in any hw until I eval the new locale's Bortle rating and the driving distance to darker areas. Your Pleiades shot was 100x better than mine but at an increased cost and an additional hw burden. I'll be progressing down the astrophotography path at a fairly slow rate for a while. Thanks again for sharing your great photos.

 

[rcreamer]

Hi Richard, Very good first attempts. I know all about the steep learning curve. Try stacking and processing in StackingWizard and AstroWizard. Both are free and really easy to use + you can use Sony RAW files straight into StackingWizard. Luke has some good tutorials on YouTube. You'll find you are a bit limited for targets with a 200mm lens - M31 is a nice exception. If you feel you want to progress, have a look around for a small refractor telescope as this would also give you the option to use narrowband filters which are essential for nebula but as with all hobbies, it starts to get expensive!

In case you weren't aware of this astrophotographer, he usually limits himself to 200mm and has some impressive shots. Here is his deep sky astrophoto page: https://www.stevenrobinsonpictures.com/deep-sky-astrophotography. Some of these are not 200mm but he has other tutoring pages showing some nice 200mm (or less) targets.