The Vixen VC200L is relatively little known and of unusual design. But it can produce images with small round stars and a
flat field to the corners of a large chip camera.
The VC200L is about the size of an 8 inch SCT or small Takahashi Mewlon. Unlike an SCT it has no front corrector lens.
As a result it is lighter than an SCT,
has a faster cool down time and seems able to avoid dew formation.
The light path is from the fixed primary mirror, at the rear, up to the secondary mirror, then down the baffle tube. The baffle tube contains a corrector lens. The
large secondary and the corrector produce a very flat field with small spot size far off axis. The on axis performance is less than my Mewlon, but the off axis
performance much better.
You focus “like a refractor” moving the draw tube and corrector lens in and out with the focuser. The primary mirror doesn’t move so there is no mirror flop.
The focuser is one speed. You can focus manually, but if you image you will likely want a motorized add-on. Most use Robofocus. However since the focuser
locks (a huge plus with a heavy camera) you may prefer to focus first with the native focuser, lock the focus draw tube, then fine focus with an added PDF,
Optec, or Moonlite focuser.
You collimate at three places: the primary mirror, the secondary mirror and the draw tube/corrector. It is involved (more places to collimate) but each step is no
harder than collimating an SCT. Once collimated, the OTA holds collimation very well and I do not need to recollimate for each session.
Triplet in Leo
If you want an OTA optimized for imaging with large chip cameras, light weight, fast cool down, a sturdy focuser that can hold a heavy camera and a very
reasonable price the VC200L may well be the scope you want.