StellaLyra · 12-inch f/4 M-LRN Newtonian
Build a large-aperture imaging system with purpose.
The StellaLyra 12-inch f/4 combines a 305mm parabolic mirror with a 1220mm focal length and a 3-inch dual-speed linear Crayford focuser. It is a substantial optical tube for a carefully planned deep-sky rig.
Choose it when your imaging goals, mount and observing space are ready for a larger Newtonian, and you want to select the camera and correction system yourself.
Mount, tripod or pier, camera and coma corrector are purchased separately. The published tube-package weight is 23kg with rings, rail and finder, before adding imaging equipment.
Make the mounting plan first.
At 1170mm long and 356mm in diameter, this tube needs more than a check against a mount’s headline payload. Consider the complete load, tube length, balance range, wind exposure and clearance throughout the mount’s movement.
Allow for the camera, corrector, filters, guiding equipment and cabling. Check the saddle connection and counterweight requirements with the mount supplier. Plan how the tube will be supported while it is fitted or removed, and arrange assistance where needed.
Think beyond the space occupied by the telescope.
Measure the route from storage to the mount, including doorways, steps and turning space. Leave room to work around the mounted tube, reach adjustment points and manage cables without disturbing the balance.
If you dismantle everything after every session, consider that whole routine before committing to this size. A fixed observing position can make a larger system more practical, but it still needs suitable storage and protection between uses.
Check how 1220mm frames your targets.
With a given camera sensor, a longer focal length places a smaller area of sky in the frame. This can suit targets that look too small in a shorter setup, while larger subjects may require a mosaic.
Use a field-of-view planner with your actual camera and several intended subjects. Check both the object and the surrounding sky you want to capture. Choose the system because that framing serves your projects, rather than expecting a larger mirror alone to deliver a better finished image.
Fine manual focus, with the camera system chosen separately.
The fitted 3-inch linear Crayford focuser provides coarse and fine adjustment. Use short exposures and a repeatable focus measurement to refine focus, then revisit it as conditions change.
Support the camera while securing it and keep cables from pulling on the assembly. Focuser diameter alone does not establish a payload rating or corrected sensor coverage. Confirm the complete camera, corrector and adapter arrangement before buying, including motor compatibility if you plan autofocus.
A coma corrector belongs in the initial budget.
A compatible corrector is required for optimum photographic results. Select it for the intended camera sensor and mechanical connections, then follow its specified corrector-to-sensor spacing.
Include filter equipment in the spacing calculation and check that the assembled system reaches focus. These are separate requirements: moving the focuser does not replace correct spacing. Keep a record of the adapter sequence so it can be rebuilt accurately after removing the camera.
Allow time for cooling and alignment.
An integrated fan assists mirror cooling, and the mirrors have collimation adjustment. Set up early enough for the tube to approach outdoor conditions and check alignment with an appropriate tool after transport.
Before starting a long sequence, inspect a short star-field exposure at the centre and corners. Work through focus, alignment, spacing, tilt and tracking one factor at a time if the result is uneven. Establishing a repeatable baseline makes later sessions easier to diagnose and more productive.
Included equipment and separate purchases
| Supplied | Required separately for imaging |
|---|---|
| Optical tube, fitted focuser and cooling fan | Suitable tracking mount and tripod or pier |
| Tube rings and Vixen-style mounting rail | Camera and compatible coma corrector |
| 8×50 straight-through finder | Adapters, filters and any guiding equipment |
| 35mm 2-inch extension and 1.25-inch adapter | Power, control equipment and collimation tool |
Specifications
| Design / aperture | Parabolic Newtonian / 305mm |
|---|---|
| Focal length / ratio | 1220mm / f/4 |
| Focuser | 3-inch dual-speed linear Crayford |
| Finder | 8×50 straight-through |
| Tube length / outside diameter | 1170mm / 356mm |
| Weight with rings, rail and finder | 23kg |
Before choosing the 12-inch
Will my existing mount carry it?
Assess the complete imaging load and the mount’s suitability for a long tube. Send us the exact mount model, camera and accessories so the combination can be reviewed. The optical tube’s weight alone is not enough to establish suitability.
Is it suitable for visual observing?
It can be used with appropriate eyepieces and a suitable mount, purchased separately. If visual observing is your main priority, compare the handling and mounting arrangement of the Dobsonian range before deciding.
Does the finder provide autoguiding?
No. It is an optical pointing aid. Guiding requires a guide camera and suitable connections or another guiding arrangement matched to the rig.
Availability reflects supplier stock and can change. Contact Dark Clear Skies to confirm dispatch timing if you need the telescope for a particular date.