a few more stellar objects part three

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we had a week straight of clear skies in seattle..very rare in the spring
this image took 22 hours of imaging time
North American Nebula

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Here is The Elephant Trunk Nebula..this was done with a 135 mm (Focal Length) lens attached to a CMOS mono cooled camera (B&W) on a portable travel mount , using special narrow band filters (halpha and sii) and color combined in Photoshop.



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This is Halpha only before cropped. I have been told by some in the AP community that they have never seen a composition like this before on this object. I checked the internet and couldnt find a match either, which is highly unusual, because this is a well known object and has been imaged extensively. It's difficult to create original compositions in AP these days (unless you have large aperture scopes), there are quite a few hobbyists

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This is my new at home system...this scope is top of the line (Takahashi) for this size 85 mm/5.3 (aperture or 430mm Focal Length). The scope and accessories cost 5 grand. All in all this entire setup costs 11 grand. It's been building for two years. (I recently also finished my portable setup, for which the top image was taken with, I will be taking that to Hawaii in two weeks..total cost of that setup was 2500 dollars). In case you dont know the expense of this hobby is related to attaining the most pinpoint of stars ...this requires high grade optics and outstanding tube design (to prevent sags in the optical train). It's not too hard with camera lenses because you can achieve coma free, distortion free optics at relatively low expense because you don't need automatic features...but as you increase the weight and size of the optical train, expense can increase exponentially
Muck like orchids , Astrophotography is an expensive hobby.
I also will be applying to the Master's Degree Professional program in Physics at UW Seattle. So I will not be moving for at least four years and can keep my orchid collection and hopefully work on building an observatory with a 12.5 aperture inch scope (total cost will be around 20 grand for all the equipment and about as far as I can go before the costs of AP goes into 6 figures). My cat will be happy too..he owns this neighborhood.


new
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These are images I have done over the past week with the new setup. I started school back up again right after Hawaii and only had some time this past week to fully try out the new system. I am attending UW Seattle Graduate program in Physics next year , so I will be able to stay here and keep my orchids for awhile (sorry Eric) but I eventually want to move to the southwest to have clearer skies (hopefully with a job in a Physics related field). All of these were done with a Hydrogen alpha very narrow band filter (meaning it filters out all but the photons from the Halpha Balmer series). I am waiting on the other filters that are much better than my previous ones, (Oiii and Sii) so that i can channel process for color.

Heart and Soul Nebula (Cassieopea) ..this is a mosaic of three panels..to get an idea of the apparent size (in the sky)..the image spans about 8 full moons along the horizontal axis

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Jellyfish Nebula (Gemini)

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Part of Spaghetti Nebula (Taurus)

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Veil Nebula (Cygnus)

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Halpha in the Balmer series (most abundant optically available material in the Universe) is optically red but you would have to be closer or have stronger eyes to see it (more cones and rods that absorb in that particular wavelength band). If you take a regular dslr and take a short exposure (ISO 1600 for 30 seconds or even 25000 ISO for five seconds) you will see red in the image (as well as other colors). Orion Nebula is a perfect example of this that anyone can manage with a regular dslr and say a 200 mm lens..no filter needed. The narrow band filters are mostly used to block out light pollution (I live in the city) and enhance contrast. One uses monochrome cameras with specific filters because the bayer filter in a DSLR distributes photons according to the bayer matrix of red, blue and green, how we see I guess. ( I am not an expert on our eyes or the bayer matrix so I am only giving the pop science explanation, I still find it a little confusing)..so in effect, you lose 66% of the information that the camera sensor receives as a function of time. In other words, you would have to image three times as long for a DSLR versus a mono CCD and you could only do this effectively in areas with much less light pollution. Mono CCD's also have the ability to cool down the sensor electronics to avoid heat buildup which causes read noise (noise in the image decreases the amount of data that is available for porcessing. There are lots of kinds of noise though due to heat, quantum efficiency, bias (light pollution), and others I forget, which can be processed out of the image ..but the cleaner the image to begin with, the better. You dont want pixels due to noise competing with pixels due to the object you are imaging. Same goes for Oiii (greenish) and Sii (blueish). When imaging galaxies or non emission nebula (plain ole dust that only reflects star light), we use LRGB filters (luminance, ,red blue and green)..which is essentially like using a DSLR, but because each filter is used one at a time, you get 100 % of the information of those photons ( as a measure of flux ) versus a DSLR's Bayer matrix (in which you get only one third for each color). Galaxies and non emission nebula are balanced in the full optical spectrum (as you are dealing with star light). (BTW, Flux is a measurement of the light that is measured from the point of reference of the observer...if you know how far the the object is , you can easily measure the actual Luminosity (and the rate of actual light transmission from the object as function of time (Power: Wattage essentially)..just like a lightbulb))
 

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