What kind of camera sensor is the Askar FRA500's 55mm image circle for?
The 55mm image circle is designed to fully illuminate and correct for sensors larger than standard full-frame (44mm diagonal). This makes the Askar FRA500 an excellent match for full-frame DSLR/mirrorless cameras and dedicated astronomy cameras with large sensors like the ZWO ASI6200 or QHY600, ensuring pinpoint stars and no vignetting at the corners.
Do I need a separate field flattener for the Askar FRA500?
No. The Askar FRA500 features an integrated quintuplet (5-element) Petzval optical design. This design inherently corrects for field curvature, providing a flat field across the entire 55mm image circle without the need for any additional flattener or reducer lenses.
How will the Askar FRA500 frame large targets like the Andromeda Galaxy (M31)?
With its 500mm focal length, the Askar FRA500 provides an ideal image scale for large deep-sky objects. When paired with a full-frame sensor, it can comfortably frame the entirety of the Andromeda Galaxy (M31), the North American Nebula (NGC 7000), or the Veil Nebula complex in a single shot.
What kind of mount is required for the Askar FRA500's 5.2kg weight?
The total imaging weight is 5.2kg for the telescope, rings, and plate. Once you add a guide scope, camera, and other accessories, your total payload will likely be around 7-9kg. A mid-range equatorial mount with a payload capacity of 13kg (30 lbs) or more, such as a Sky-Watcher HEQ5 or iOptron CEM26/GEM28, would be a stable platform for imaging with the FRA500.
What are the 85mm and 158mm back focus distances on the FRA500 for?
These are the two primary connection options for your imaging train. The 158mm distance is measured from the M86x1 thread on the rotator, giving you maximum space for complex setups. The 85mm distance is measured from the M48x0.75 thread on the included conical adapter, which is a more common connection for DSLRs or cameras with integrated filter wheels.
Can I use the Askar FRA500 for imaging the Orion Nebula (M42) from a portable setup?
Absolutely. The Orion Nebula (M42) is a perfect target for this telescope. Its f/5.6 focal ratio is fast enough to capture faint nebulosity quickly, and its 500mm focal length will resolve fine details in the Trapezium region. Given its total weight of 5.2kg, the FRA500 is an excellent choice for a high-performance portable imaging rig.
