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25

Not quite like in the photo above, which shows more than what the naked eye can see, but yes, absolutely! Our galaxy (well, the chunk of it visible from these parts) is a naked-eye object. The fact that your question even exists shows how much time is now spent by people under light-polluted skies. It will not be visible from the city, however. You need to ...


14

Part of why you don't see colors in astronomical objects through a telescope is that your eye isn't sensitive to colors when what you are looking at is faint. Your eyes have two types of photoreceptors: rods and cones. Cones detect color, but rods are more sensitive. So, when seeing something faint, you mostly use your rods, and you don't get much color. Try ...


9

If you prefer to make visual observation only, while some procedures are almost the same, the criteria for a telescope gets easier and the price is lower than with astrophotography. The light gathering of the telescope becomes one of the most important criteria and a dobsonian telescope could be a good choice for that, specially one with at least 6 inches of ...


6

There are a couple of main sources of intrinsic error (that is, not associated with counting photons from your source) which CCD's have. The first is as you have already mentioned called read noise. Here is a reasonable definition of read noise (taken from Romanishin's free pdf on Photometry): After an integration (exposure), the CCD must be read out to ...


5

The reason is that the exposure on the camera is set so that the main subject of the image is properly exposed, ie not too dim and not too bright. Because the typical objects being photographed are quite bright, the image detector (camera) will not get enough light from the stars for them to show up.


5

Dithering is as much an art as a science and depends on many factors including, but not limited to: The type of object being observed (point source, small extended object, large extended object) Telescope parameters (The field of view of the telescope relative to the size of the object, optical quality, size and type of abberations, etc) The quality of the ...


4

TLDR: Cheap optics - the image gets worse with each new element added, pretty quickly. High end optics - the image may get better, may stay pretty much the same, or may get worse; if it does get worse, it's by such a small amount that you can usually ignore it. This assumes a scope that is in good shape, otherwise all bets are off. Now the long version: A ...


4

Since you say you're a programmer, I see where criterion #1 comes from. But telescopes are not computers, you can't upgrade the CPU today, the RAM tomorrow, and so on. A scope is defined largely by its aperture (the diameter of the objective lens or mirror). That puts a major cap on pretty much everything else, performance-wise. Aperture is like an old ...


3

It's because of the short Dynamic range of the camera. The human eye has a very large dynamic range which allows it to see at the same time, lights of low exposure and lights of high exposure. The same problem exists when you try to capture a photo against the sun light. Either the sky is completely white and the object is correclty lightened, or the sky is ...


3

A scale of distance would not make sense as a photograph often shows objects at vastly different distances from the observer and thus the distance of two objects on the photograph does not translate directly into a distance in real space. Or in other words: a map of an area on earth is mostly a projection of a 2D area onto a 2D map while a astronomical ...


3

For solar physics, the false colors were used to quickly identify the filter that was used, and possibly even the instrument itself. So, for instance, SOHO/EIT, there are three filters, each one typically shown with a color that are ordered by spectrum (eg, the 'green' false color image has a spectral sensitivity between the 'yellow' and 'blue' images. ...


2

Fundamentally yes, practically yes as well. All physical optical surfaces will add some scatter, 'there is no such thing as a perfect optical surface'. Even flat mirrors are not really flat. In practical terms it also depends on what you are doing, but yes generally adding additional surfaces into the optical path will lead to degradation of any 'image'. ...


1

IRAF (Image Reduction Analysis Facility) is a free program that can help you with aligning your images of stars and many more astronomy related tasks for image analysis. You can download IRAF here. In order to analyze your images in IRAF they will need to be in the .fits (File Transfer Image System) image format. Most CCD astronomy cameras will output ...


1

If all you need to do is to stack the images, then you could use some dedicated astrophotography software to achieve this. You will want to search for "image stacking astrophotography" or something similar. Here are a few which I have used which do the trick ... DeepSkyStacker This tool is suited to deep sky objects like galaxies and nebula. It would be ...


1

Certainly, low light and taking and good "heaven", you can see much of the Milky Way. the only thing you need to know is to know where to look. However, some parts of it are brighter than others. The center of the galaxy is the most spectacular and is in the same direction as the constellation Sagittarius. This area of ​​the sky can be seen every year in ...


1

If you really want to do astrophoto, then you must use a driven mount, period. Goto is fine, but it's not a requirement, all you need is a tracking mount (a mount that spins around one axis, doing 360 deg in 24 hours, and spins steadily, that's all) - this is something many beginners are confused about. Many people will tell you to not start with AP ...



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