Do I need to buy a separate field flattener for the Askar SQA70?
No. The Askar SQA70 uses a 5-element Quintuplet Petzval optical design, which is "self-flattening." It supports full-frame imaging with no additional flattener and no back focus calculation.
Can the Askar SQA70 be used with a full-frame camera?
Yes. The SQA70 is specifically designed to produce a 44mm image circle, which is large enough to cover a full-frame (36x24mm) sensor.
What kind of deep-sky objects are a good match for the Askar SQA70's 336mm focal length?
On a full-frame sensor the 336mm focal length covers about 6.1 x 4.1 degrees. That suits large targets such as the Andromeda Galaxy (M31), the North America Nebula (NGC 7000) and the Heart and Soul Nebulae (IC 1805 and IC 1848).
How do I attach an electronic focuser to the Askar SQA70?
The manual's steps: remove the thumb screw, remove the coarse adjustment knob with a 2mm wrench, fit the motor bracket with standard M4 screws without locking them, choose a 5 to 6mm flexible coupling, insert the EAF into the coupling, then lock the EAF mounting screws and finally the M4 fixing screws.
What is the purpose of the 360° rotator on the SQA70's focuser?
The 360° rotator allows you to change the orientation of your camera to frame your target without loosening the camera from the imaging train. Its precision scale lets you record the angle and return to it, which helps with mosaics and later sessions.
How do I use the different back focus distances between 37mm and 68mm?
With any connection distance between 37mm and 68mm you can shoot directly once the OTA is in focus; 55mm is recommended. Add or remove spacers between the rear adapter and the sensor to land in that range.
What are the included M42, M48, and M54 adapters used for?
The M42, M48 and M54 adapters can be used to mount various accessories. The M48 adapter comes fitted to the OTA and has an M48×0.75 filter thread; all three are toothed and ribbed so they turn by hand without slipping.
Can I attach filters to the Askar SQA70?
Yes. The included M48 adapter has an M48×0.75 filter thread for a 2-inch filter. Alternatively, you can place a filter drawer or filter wheel in your imaging train, provided the total light path remains within the 37mm to 68mm back focus range.
Will the Askar SQA70 work for imaging the Orion Nebula (M42) from my backyard?
Yes. At 336mm a full-frame sensor covers about 6.1 x 4.1 degrees, enough for M42 and much of the surrounding sword region. From a light-polluted backyard, using a dual-band or multi-band narrowband filter will help isolate the nebula's emission lines from the skyglow, and the fast f/4.8 optics will help capture the data quickly.
What does the "2x ED Elements" in the Askar SQA70's design do?
The two ED (Extra-low Dispersion) glass elements are specialized lenses that control chromatic aberration, or "color fringing." They help bring different wavelengths of light to a common focus, which reduces colored halos around bright stars.
