Buying guides
Which one, for the sky you actually have
A hub weighs a whole family against itself. A guide takes one question instead — a figure to spend, a first telescope for someone who has never found anything but the Moon, what fits in the boot of a small car — and answers it with a short ordered list and the reasoning that produced the order.
- Getting started
A first telescope, and the three figures that decide it
Aperture, mount and eyepiece fitting decide whether a first telescope is used or shelved. Five instruments read against those three.
- Getting started
The child’s telescope that survives the second night
Most children’s telescopes are abandoned after one evening. What separates the ones that are not: setup, steadiness and a first target that works.
- Choosing
Aperture against the weight of carrying it
A large telescope that stays indoors shows nothing. Five instruments read on aperture against what has to be carried outside.
- Choosing
What goes in the luggage and still works
Packed length, total carried weight and setup time — the three figures that decide whether a telescope travels, read across five instruments.
- Eyepieces
Three eyepieces, and why not five
A low power, a medium and a high, spaced so none duplicates another — with the arithmetic that decides the spacing.
- Imaging
A camera, a tripod and something that turns
The sky moves, and that is the whole problem. What a tracker, a filter and a lens do about it, without a telescope in the path.
- Mounts
Why the mount is bought first
Tubes are replaced; mounts are not. Payload, drive and polar alignment provision, read across five mounts and trackers.
- Observing
What still works under a bright sky
Light pollution takes the faint objects and leaves the bright ones. What to point at, and what a filter can and cannot recover.
- Solar
Reading an eclipse listing
Standard cited, notified body, laboratory named, authentication code — what each of these is, and what this site does not say.
- Care
Why the session ends at midnight, and what stops it
Dew forms when the optics fall below the dew point. A shield delays it, a heater prevents it — and the figure that matters is length.
- Care
The adjustment that makes a reflector sharp
A Newtonian out of collimation cannot show a point. What each collimator type does, and which one answers which question.
- Getting started
What binoculars teach before a telescope is bought
Exit pupil, true field and steadiness are learned faster with binoculars — and they decide which telescope is worth buying afterwards.
- Choosing
The numbers that mean something, and the ones that do not
Maximum magnification, "professional" and "HD" say nothing. Aperture, focal length and eyepiece diameter say everything.
- Filters
Filters remove light. That is the whole trick.
Narrowband, broadband, colour and neutral — what each removes, and why no filter makes anything brighter.
- Accessories
Five things that come out every night
A red light, a chart, a seat, something to keep dew off and a way to aim — the accessories that outlast every telescope.
- Choosing
What the first one taught you to buy
The second telescope is bought for what the first could not do. Five instruments read against the five commonest limits.
- Observing
The one object that is never disappointing
The terminator, the phase, and why full Moon is the worst night to look. With the filters and eyepieces that suit it.
- Observing
Star-hopping, and the tools that shorten it
A finder, a chart and a low-power eyepiece find more in an evening than any pointing system finds without them.
- Imaging
Two threads, one distance, and what goes between
T2, M42, M48 and the back focus that decides whether anything reaches focus at all. The parts, in the order they go on.
- Observing
The list that gets packed, and the one that gets forgotten
A dark site rewards preparation and punishes a missing part. What goes in the bag, and what is remembered too late.
- Care
Where it lives between sessions
Damp, dust and knocks. What a case, a cover and a dry cupboard each prevent — and what breathability has to do with it.
- Care
Four causes, in the order to check them
Seeing, cool-down, collimation and focus. Three of the four are free to fix, and the fourth is a screwdriver.
- Mounts
The mount is the camera’s tripod, and it has to turn
Payload with margin, polar alignment, and the periodic error nobody publishes. What to read on an imaging mount.
- Observing
Small, bright, and worth the magnification
Planets are unaffected by light pollution and limited by the air. What aperture, focal ratio and patience each contribute.