Many people construct special “light boxes” for this. For example, with small scopes you can use a tablet screen showing white otherwise a bright LED shining on white t-shirt stretched over the aperture. Flat Frames: Shots taken with a uniform neutral-color light source in front of telescope.Aim for 20+, especially if you don’t “dither” (dithering involves moving the aim of the scope by a few pixels between each frame captured, in order to eliminate pattern noise).

You are basically taking a photo of the thermal noise. Dark Frames: Same ISO, exposure time and (sensor) temperature as Lights, but with cap on.under a minute, several dozen light frames are usually taken (or hundreds for very short exposures of a few seconds). There is no limit to how many you can take (more = better due to less noise). Taking several, all at the same ISO and exposure time will reduce noise and bring out more detail after they are stacked together by a program like Deep Sky Stacker. Light Frames: The actual images of your subject.In essence, we need 4 kinds of images for a full set that can be pre-processed with DSS: When we talk about “calibration” of an image, we refer to a process that involves the subtraction of noise and optical defects from our images. So, before jumping into a StarTools example workflow, a few tips about getting good data with your DSLR, as well as calibration/stacking with Deep Sky Stacker (DSS – the best free tool for this process). “combined) exposures of the object of interest. You can always tweak some more of course, but the example process I am going to demonstrate on this post will get you to the following result in just a few minutes:Īpart from very powerful and quite easy, StarTools is also inexpensive, at just 60 AUD, it is available on Windows, Mac OS X and Linux and even has a full-featured evaluation version which you can download freely – only saving is disabled (you can still take a screenshot of your result) – but you have all the time to make sure it’s for you as it doesn’t expire.įor StarTools to work its magic it requires “good data” which means properly calibrated and stacked (i.e. StarTools has made my life much easier as it does many things that require many manual steps in other software almost automatically, allowing me to get decent results from an image in just 10-15 minutes. Noisy data gives you a hard time when processing, so it would initially take me quite some time and effort to get to pleasing results, even with dedicated software. Using a DSLR camera for astrophotography has you dealing with quite noisy data, and the issue is compounded if you are shooting from the city under light-polluted skies.

X particles 3.5 demo noise patch