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Solar

What makers publish for an eclipse, and what to read

This page does not tell anyone how to observe the Sun safely. It shows what makers publish for solar filters and trackers, and where the conditions of use are set out: in the maker's instructions and the standard the listing cites.

By

The standard the listing cites

Astromania’s Deluxe 100 mm solar filter cites ISO 12312-2:2015 and names its film, Baader AstroSolar. That is the first thing to read in any solar filter listing. See ISO 12312-2 solar viewing.

The fit

A solar filter goes on the front of the telescope and covers the full aperture. Astromania publishes the tube outside diameters its cell fits, 70 to 92 mm, and three padded clamping screws. Measure the tube, or its dew shield, before ordering.

The maker’s warnings

The listing says never to use the telescope if the filter is in any disrepair. Inspect the film every time, cover the finder, and follow the instructions supplied with the filter and the telescope.

Following the Sun

Trackers and GoTo mounts that offer a solar rate keep the Sun centered during an eclipse. SLIK’s ECH-630 lists sidereal, lunar, solar and time-lapse speeds; the Star Adventurer GTi lists lunar, solar and sidereal rates.

What this site does not do

Advise on use. A comparison table cannot replace the manufacturer’s instructions, and no page here says a filter makes solar observing safe.

What suits your sky?

You want to observe an eclipse
Only the instructions of the device’s maker apply.
You own a filter
A filter sold for the night is not a solar device.
You are looking for a method
This site describes none and validates none.
You have a doubt
A doubt about a solar device means the device is not used.

Picking by what you want to see

What makers state

Some makers publish a solar specification for certain products. This site reports it without endorsing it.

What is not stated

Most products carry no solar specification, and that silence is itself information.

What this site does not do

It describes no solar observing, prescribes no configuration and validates no device.

What decides what you will see

The stated solar specification
Where present it is the maker’s declaration. This site reports it and confirms nothing.
The stated maker’s instructions
They are the only reference. No site replaces them, this one included.
The stated device condition
Makers state inspection conditions. They are part of the specification, not an option.

Which figure for which target

The productWhat is publishedWhat this site concludes
Night filterNo solar specificationNothing
EyepieceNo solar specificationNothing
TelescopeThe maker’s manualNothing
Solar deviceIts maker’s instructionsNothing

What observers get wrong

Taking a night filter for a solar device
A filter that screws onto an eyepiece is not a solar observing device.
Following a method found online
Only the instructions of the device’s own maker apply. This site describes no method.
Using a device without inspecting it
Makers state inspection conditions. They are part of the device.

By the observer you are

The curious
Will find here what makers publish, and no more.
The instrument owner
Looks in the maker’s manual, not on this site.
The one in doubt
Does not use the device. That is the only answer this site gives.

Care, storage and working life

A solar device is inspected according to the conditions its maker publishes, and nothing else. This site reports that these conditions exist and describes none of them.

  • Only the maker’s instructions apply, without exception.
  • A device showing any defect is not used.
  • A device is never modified or adapted.
  • This site validates no device and no method.

Safety

This site publishes stated specifications, describes no solar observing and validates no device. Only the maker’s instructions apply.

  • Solar filters screwed onto an eyepiece are not solar observing devices.
  • No instrument is pointed at the Sun without a device provided by its maker.
  • An instrument left pointed can concentrate sunlight with nobody at it.
  • Children are never left near an instrument during the day.

The three, and the reason for the order

  1. Solar filters

    Astromania Deluxe Solar Filter 100 mm

    Baader AstroSolar film · ISO 12312-2:2015 cited · fits tube outside diameter 70–92 mm · 75 mm clear aperture · 100 mm cell · three padded screws

    Astromania's Deluxe solar filter: Baader AstroSolar film in an anodized aluminum cell 100 mm across, with a 75 mm clear aperture, three padded clamping screws for tubes 70 to 92 mm in outside diameter, citing ISO 12312-2:2015.

    Best for: The front of a telescope whose tube outside diameter has been measured first

    ≈ $35

    Check price on Amazon Read the review: Astromania Deluxe Solar Filter 100 mm
  2. Star trackers

    SLIK ECH-630 (618-803)

    Sidereal, lunar, solar and time-lapse speeds · 20 hours on 4 AA · 22.4 oz in the bullets, 23 oz in the title · LCD menu

    SLIK's ECH-630: a compact motorized star tracker with sidereal, lunar, solar and time-lapse speeds, an LCD menu and up to 20 hours on four AA batteries, about the size of a 24-70 mm lens, with an optional SMH-250 polar head.

    Best for: Backcountry night photography where batteries must be replaceable and the speed switchable

    ≈ $440

    Check price on Amazon Read the review: SLIK ECH-630 (618-803)
  3. GoTo mounts

    Sky-Watcher Star Adventurer GTi (S20590)

    11 lb payload · full GoTo equatorial head · built-in illuminated polar scope · Wi-Fi · USB and autoguider ports

    Sky-Watcher's Star Adventurer GTi head kit: a full GoTo equatorial tracker with an 11 lb payload, built-in illuminated polar scope, Wi-Fi, USB and autoguider ports, SNAP shutter control and a dual-position counterweight.

    Best for: A camera and lens or a small astrograph under a dark sky

    ≈ $579

    Check price on Amazon Read the review: Sky-Watcher Star Adventurer GTi (S20590)

What gets asked before buying

Is any filter here certified safe?

This site does not certify safety. It reports the standard a listing cites, such as ISO 12312-2:2015, and points to the maker's instructions.

Where does a solar filter go?

Over the front of the telescope, covering the full aperture, as every maker of these products describes. The finder must be covered or removed.

Do trackers follow the Sun?

Some offer a solar rate, such as the SLIK ECH-630 and the Star Adventurer GTi. The filter still goes on the front of the optics.

Each pick, and what it was chosen for

What each band of spending shows you

Entry level

$35 – $326

3 models

Mid range

$439 – $579

4 models

Upper range

$905 – $2 299

3 models

The short sight

What this selection is drawn from

The models above are taken from the catalog of this site. Specifications are the ones the maker publishes and the ones on the Amazon page; prices are the Keepa reading for the date shown, and both change. Ranking uses declared specifications, the weight of stated strengths against stated limits, and price. Nothing here has been pointed at the sky by us, and the page makes no such claim.

Last checked on

Any figure written into the body of this page was true on the day it was written. The amount shown next to each instrument is requested from the retailer as the page loads, and it is that amount, not the text, that stands.