ZWO recently introduced the larger OAG-L for $199. The Standard ZWO OAG used on the author’s telescope.
#Best telescope for astrophotography under $200 full#
Parts and adapters included with the standard ZWO OAG. The basic version costs only $128 but I highly recommend the helical focuser version ($187) since sub-millimeter focusing precision isn’t possible without a focuser. The standard OAG made by ZWO is quite versatile, having been designed with M42 / M48 threads on both the camera and telescope sides. The QHYCCD OAG on the author’s telescope showing its very slim profile. The prism is relatively small at about 8x8mm.The OAG needs to be removed to adjust the prism stalk height.Designed to work with QHYCCD equipment use with other brands requires minor modifications (screwing threaded adapters to either side).Can be bolted directly to QHY cameras and filter wheels.Mono-block (one-piece) design with the body directly attached to the focuser, and thus less flex.Very slim 10mm body with 3mm of thread, totaling 13mm of required back focus.Adapters are provided to thread onto the telescope.
These OAGs bolt onto the camera or filter wheel with the provided screws. The QHYCCD OAGs come in three sizes, priced at $180, $230, and $280, to accommodate most sensors, from the smaller one-inch sensors up to full-frame and even larger. Here we look at four relatively simple and low-cost options ($100 to $200) from QHY, ZWO, and a less-known option from Hercules. If it does, I’d recommend an OAG over a guidescope. The primary limiting requirement is having enough back focus with your optical setup. My preference has always been the off-axis guider because it’s more accurate, especially for reflectors and longer focal length instruments. The two most common methods are: 1) a secondary guidescope on top of the main imaging telescope, and 2) a small device attached right next to the imaging camera, i.e., an off-axis guider (OAG). Credit: Rouzbeh BidhashariĮven with the best mounts and polar alignment, most imagers need to guide the mount to ensure near-perfect tracking of the sky. Be sure to pick the one that best matches your gear and needs. There are several off-axis guiders to choose from to get you started.