StellaLyra · 8-inch f/12 M-LRS Classical Cassegrain
Settle in for a closer study of the night sky.
The StellaLyra 8-inch Classical Cassegrain combines a published 200mm aperture with a 2436mm focal length and nominal f/12 focal ratio. It suits observers who enjoy concentrating on lunar features, planets and double stars, with the option to build a camera setup for smaller targets.
This is an optical tube assembly. Choose the mount, diagonal, eyepieces or camera around the observing you want to do, and assess the complete working kit before deciding where it will live.
Long focal length, purposeful framing.
With a given eyepiece, a longer focal length produces higher magnification and a narrower view. That can be useful for exploring a small region of the Moon or studying a planet, but locating a target and keeping it centred become more demanding.
Think about an observing session rather than a maximum magnification figure. Start with an overview, centre the subject, then increase power while the view remains sharp. On an unsteady night, backing off the magnification can make the observation more rewarding.
If sweeping wide star fields is your main interest, compare the field of view of other telescope designs before choosing. The complete eyepiece and telescope combination determines the framing.
Check the mounting interface first.
The lower mounting plate is Losmandy-style; the upper accessory rail is Vixen-style. Confirm your mount’s saddle accepts the lower plate before planning the rest of the setup.
The published tube weight is 8.2kg. Add the diagonal, eyepiece or camera, finder and any other attached equipment when assessing the load. A mount that remains steady during focusing is especially valuable at the magnifications this telescope can provide.
Balance the equipment you will actually use.
A diagonal and heavy eyepiece change the balance differently from a camera and its adapters. Fit the intended accessory train before balancing, supporting the telescope while adjusting its position.
Check that the assembly can balance within the available rail travel. Allow space behind the tube for the focuser, extensions and accessories, and check clearance around the mount throughout the intended pointing range. Include safe fitting and removal in your plan if the telescope will be transported regularly.
Fine focusing with a stationary primary.
A rotatable 2-inch dual-speed Crayford focuser provides coarse and fine control while the primary mirror remains fixed.
Approach focus slowly, let vibration settle and make the final adjustment on the target you are observing. Secure the diagonal or camera without relying on cable tension to hold anything in place. For motorised focusing, check the motor bracket and coupling against the supplied focuser before ordering additional equipment.
What your eyepieces will deliver.
Magnification is the telescope focal length divided by the eyepiece focal length. These examples help you plan a useful range:
| Eyepiece focal length | Approximate magnification |
|---|---|
| 25mm | 97× |
| 15mm | 162× |
| 10mm | 244× |
Eyepieces are separate purchases. These figures are calculations, not a promise that a particular night will support the higher power. Atmospheric steadiness, target altitude, cooling and alignment all influence the useful magnification.
Configure the rear optical path for your accessories.
Two 25mm extension rings and one 50mm ring are supplied. They allow the focuser position to be configured for different observing or camera arrangements.
Work out the diagonal or camera connection first, then use the extension combination that brings focus within the focuser’s travel with some adjustment remaining. Fitting every ring is not a universal setup. Keep a record of the arrangement that works for each accessory combination.
Prepare for detail before increasing power.
Allow the telescope to approach outdoor conditions before assessing its best image. Centre a suitable star when checking focus and alignment, and use a collimation procedure appropriate to a Classical Cassegrain if adjustment is needed.
Investigate one cause at a time when the view is soft. Unsteady air, incomplete cooling, imperfect focus and misalignment call for different responses. Avoid changing collimation simply because a low-altitude target is shimmering.
Adding a lunar or planetary camera.
A small sensor can make target acquisition surprisingly demanding. Align a separately purchased finder and practise centring the subject at the native focal length before adding amplification. Tracking makes it easier to keep the target in view while refining focus and exposure.
Choose any Barlow around the camera’s pixel size and the seeing. Capture short test sequences before committing to a longer run. For deep-sky imaging, consider the f/12 focal ratio, narrow framing, exposure time and guiding requirements together; those needs differ from short lunar or planetary video captures.
Included and purchased separately
| Supplied with the OTA | Choose separately |
|---|---|
| Classical Cassegrain optical tube and focuser | Compatible mount and tripod or pier |
| Lower mounting plate, upper rail and finder base | Finder or pointing aid |
| 2-inch to 1.25-inch adapter | Diagonal and eyepieces for visual use |
| Two 25mm and one 50mm extension rings | Camera and its required adapters |
Specifications at a glance
| Optical design / published aperture | Classical Cassegrain / 200mm |
|---|---|
| Focal length / nominal ratio | 2436mm / f/12 |
| Mirror material | Quartz primary and secondary |
| Secondary obstruction, housing included | 73.5mm, current supplier specification |
| Published tube length / outside diameter | 536mm / 231mm |
| Published tube weight | 8.2kg |
Before ordering
Will it fit a Vixen-only mount saddle?
The supplied lower plate is Losmandy-style, so do not assume it fits a Vixen-only saddle. Confirm a suitable mounting arrangement before buying. The Vixen-style rail on top is the accessory rail.
Is a finder, diagonal or eyepiece included?
No. The finder base and eyepiece adapter are provided, but the finder, diagonal and eyepieces are separate choices. Include them in the complete setup budget.
Should I compare it with the 6-inch model?
Yes. Compare the full mounting load, storage space and intended targets. The 6-inch Classical Cassegrain offers a smaller option with different mounting requirements. Choose the complete system that fits your observing routine.
Availability reflects supplier stock and may change. Contact Dark Clear Skies to confirm dispatch timing if you need the telescope for a particular date.