Omegon N 305/1500 Dobson

The Omegon N 304/1500 (12" F/5) will show you noticeably more than a 10"-class scope, delivering roughly 0.4 magnitudes greater depth and gathering 45% more light. Where a 10" delivers satisfying views of major Messier objects, galaxies like M51 appear 'significantly beefier' and dust lanes in M31 become visible at the 12". Lunar and planetary work is very capable, though the F/5 design produces coma that benefits from a corrector (adding £200+) for the sharpest planetary views—this is not a critical issue for deep-sky work. The scope's real strength lies in its ability to sustain long observing sessions on faint objects; one user successfully logged 107 of 110 Messier objects in a single night, primarily using just a 21mm eyepiece for wide-field sweeping.

However, the 12" F/5 solid tube presents logistical trade-offs that genuinely affect real-world use. The 53 lb OTA and 72 lb total weight, combined with its 1.5-meter length, makes it a committed piece of furniture—it will not fit lengthwise in most cars without reconfiguration, and moving it becomes a two-person job or requires a hand truck. Thermal stabilization takes ~60 minutes (versus 40 for a 10"), meaning you cannot take it outside for a quick 30-minute session. Multiple experienced users report that after the initial excitement, the 12" solid tube began seeing less use than a 10", and some actively regretted the purchase because the bulk itself became a friction point discouraging observing. For a stationary backyard setup with a hand truck and sheltered storage, this is far less of an issue; for future dark-sky trips with family in a car, you may find yourself wishing you had the portability of a 10" or the modularity of a 12" truss design.

For observing program completion and detecting subtle detail, the 12" is genuinely the better instrument. But the consensus from users who own both sizes is stark: 'The best telescope is the one you use.' If the 12"'s bulk discourages regular observing, a 10" that gets used weekly will show you more in the end than a 12" that sits idle. Consider whether your observing will be truly backyard-focused and sheltered, or whether regular transport and quick-setup sessions matter to your long-term engagement with the hobby.