@PaulRix, you’ve touched on the subject of color before. I feel like I am about to show some serious ignorance about light but it’s a burning curiosity so I’ll ask anyway. How “real” are the colors? And if the image is monochrome originally then what do the colors we are seeing represent? Is a green or a purple in any way representative of the visible wavelength that is striking the sensor?
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It’s a very good question Eric. With the image above, I am using a ‘narrow band filter’ which only lets certain wavelengths through to the camera sensor. In this case the filter allows wavelengths associated with Hydrogen-Alpha, which is in the red part of the spectrum, and Oxygen III which is blue/green, to pass through to the camera sensor. In the image preview above there has been no color balancing or correction done, so it is as the camera see it. The area is very rich in hydrogen, so it looks predominantly red. Remember though that the image is being shot through a filter, so the colors are still ‘off’.
Narrowband imaging has its advantages and disadvantages. The filters block out a lot of light, so you need a lot more exposure time, but the advantage is you can image under the light of a full moon, or in a light polluted city.
Certain targets simply look better when you use narrowband, the Horsehead being one example. The Hubble Space Telescope uses narrowband imaging for scientific purposes. It allows astronomers to identify what kind of gasses they are looking at.
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Thanks Paul!
I read somewhere many, many years ago that celestial “clouds” are way less dense than science fiction can acknowledge. Like imagine an individual particle of cigarette smoke. Now imagine its nearest particulate neighbor is 100 miles away. That is the sort of density we are looking at.
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Yep, space is incomprehensibly big…
I am always in awe looking at astro images. Thanks for posting these, Paul!
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Yeah it is mind blowing. The only reason we can even see those nebulae is that we are looking through light years of thickness.
IIRC the densest nebulae out there are still less dense than the best vacuum that we can make here on Earth, it is ridiculous.
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I was being an Ass with my ‘predator vision’ post but I did not know that…
I pulled another all-nighter last night 
This is NGC2359, more commonly called Thor’s Helmet. It is classified as an Emission Nebula, but it has a lot in common with a planetary nebula because it is the product of a dying star. The difference is that the star in question is large enough to go Super Nova, which will happen relatively soon (in the grand scheme of things).
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It was clear again last night, at least until about 2:30am. Here is the first capture of the night… NGC7479, also refered to as the Propeller Galaxy, which is found in the Constellation Pegasus. This galaxy is estimated to be about 105 million light years from us. That means the dinosaurs were walking the earth during the Cretaceous Period when the photons we are seeing here started their journey to end up hitting my camera sensor.
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Last one for awhile, as I will be on the road much of next week and the weather forecast doesn’t look suitable anyway.
This is the Crab Nebula (Messier 1) which is a Super Nova Remnant. M1 is an interesting object. The Super Nova itself was seen here on Earth in 1054AD. It was bright enough to be seen in broad daylight. Chinese and Japanese astronomers of the time wrote about it.
Wikipedia has a lot of information about M1 here.
The image could have done with more exposure time, but unfortuantely the clouds rolled in and put an end to the night’s imaging session.
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I had a few hours to play with last night before thin cloud rolled in. This is IC417, an emission nebula in the constellation Auriga. It needs a lot more exposure time to pull out all the details, but it was better than nothing, and really, I was just trying to get auto-focusing working with my telescope. In that regard, it was a successful night.
Auto-focusing was the last thing I needed to get working to allow a completely automated imaging run. I will need to test the process over several more nights, but eventually, I should be able to get everything up and running, and then go to bed at a fairly normal hour. 
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Yet another imaging session prematurely ended by cloud cover. I will definitely be returning to this one when I get a chance.
IC 1795 a.k.a. the Fish Head Nebula, which is just a small part of the Heart Nebula found in Cassiopeia.
This a stack of 18 x 3 minute exposures.
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The lens isn’t focused on infinity?
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You would think so, but no. I guess it comes down to the many variables involved when combining long focal length, atmospherics such as temperature and humidity plus the angle at which you are shooting, which changes as the night progresses - the lower in the sky your target is, the more atmosphere you are shooting through.
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My Seestar S50 ‘smart telescope’ came in yesterday.
I ordered this back in July and they are now getting caught up with the pre-orders. It won’t match the quality of images I am getting from my higher end setup, but it is going to be great for those nights when it is not worth the time and effort to set up the larger rig. Of course, cloud and rain is forecast for the next few nights…as is usually the way when you have new astronomy gear to play with.
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It looks like I will get a chance to play with the SeeStar this evening. It comes with a white light solar filter, so I just gave it a try on the Sun.
This is a single frame snapshot saved straight to my iPhone. Lots of sunspot activity today!
Here is the Seestar itself. It’s going to be very easy to haul around. Everything fits into a nice compact travel case that is included in the package.
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Yeah, there is some sun spot activity these days.
Mind boggling when you think about it: some of those spots are larger than Earth.
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Unfortunately the sky conditions were less than great this evening. Even so, I still wanted to try out the SeeStar under the stars.
First, this is a phone shot that illustrates the conditions I was trying to shoot in.
All things considered the little scope did quite well.
M42 - The Great Orion Nebula. I will come back to this one on a clearer night.
The Moon is easy enough to get a good image, even when the sky is thinly veiled by cloud.
The Crab Nebula is definitely there, but just a smudge with very little detail.
It is probably not fair of me to post these images because the sky conditions were so poor. The Seestar scope is capable of delivering far better images. One thing I can say is that the Seestar is very easy to set up and use. I will try again with it tonight if the conditions are a little more favorable.
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You have literally no idea how much I frigging love moon shots.
Thank you so much- can I put it in my folder for randomized windows Desktops?
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