Once an astrophotographer has selected their equipment, the next question is: what software should I use? There are a lot of options depending on the type of imaging one desires to do and the utility one needs, ranging in price from free to hundreds of dollars. But one piece of software rises above the rest both in its low price and its high utility: SharpCap.
SharpCap comes in two price tiers: free, and the £12/year (nearly $17 USD at time of writing) pro version. The free version has several useful tools, but the pro version provides more valuable utilities. New tools arrive continually as development progresses on the software.
SharpCap has an ever-increasing set of useful tools for astrophotographers. First, it provides a quick and easy way to view the input from your camera. You can set the exposure time and gain, and the live feed is displayed with a screen-stretchable histogram. This capability is great for framing, focusing, and aligning your telescope, as well as capturing planetary videos or a series of deep sky target images.
Images and videos can be saved in standard formats (AVI, JPG, TIF, etc) as well as astronomy formats (SER, FITS), and a separate text file saves the capture settings. SharpCap supports a vast array of cameras, including those using ASCOM, DirectShow, native drivers, and frame grabbers. Notably, it does not work with SBIG cameras or DSLRs (although ASCOM drivers for DSLRs are in development), but a folder-monitoring tool works as a catch-all for cameras that do not work directly with SharpCap.
Second, SharpCap can control devices besides the camera. Using ASCOM, it can communicate with your mount, focuser, and filter wheel all in one place. The pro version comes with built-in Python scripting so you can add your own functionality.
Third, it’s a one-stop shop for all your setup steps. The pro version has a polar alignment routine that can be used on any mount, whether the mount is motorized or not. It uses either your imaging or guiding camera to plate-solve, determining the scope’s pointing position near the north or south celestial poles from the stars in the image. It then tells you how far, and in which direction, to move the mount while continuously updating until you are within mere arcseconds of perfect polar-alignment.
The free version of SharpCap has a bevy of focusing aids based on FWHM (star size), Bahtinov mask spikes, and more. Also available in the free version is a live stacking/EAA (electronic-assisted astronomy) tool that aligns and stacks long-exposure images as they come in. That’s great for getting the best views for personal observing or public outreach events, essentially post-processing multiple images in real time. It also includes a plate-solving utility using AstroTortilla, ASTAP, astrometry.net’s ANSVR, or All-Sky Plate Solver (ASPS) to center your ASCOM-connected mount.
SharpCap shines as a planetary imaging platform. It’s simple to crop the camera feed to increase frame rate, and it takes full advantage of the high-speed transfer capabilities of USB 3.0. The Pro version has a seeing-triggered capture utility that monitors the seeing and only records frames above a user-set quality value, capturing those fleeting moments of good seeing faster than human reaction time. The Pro version also includes feature-tracking, which can slew the mount to keep your target centered. Meanwhile, the free version includes an ADC (atmospheric dispersion corrector) alignment tool. In both versions, users can save capture profiles for fast switching between filters and targets using custom-named files, including WinJUPOS-compatible filenames.
SharpCap’s seeing monitor tool, here keeping watch on the Moon, insures you record only the best frames. Credit: AstronoMolly
The latest version of SharpCap Pro, version 4.0, includes sequencing tools that were absent in the previous version. It can now do target selection and framing, control PHD2 or Lacerta MGEN3 for guiding and dithering, automatic focusing, and filter changing. The sequencer interface is a little cluttered and unrefined, but the online documentation is helpful.
SharpCap Pro’s sequence editor. Credit: SharpCap
SharpCap is a robust and intuitive astrophotography tool that continues to improve. From setup to planetary imaging to live stacking and deep sky imaging, its array of utilities and functionality is unmatched for the price.
MSRP: Free version or £12/year SharpCap Pro version