Mounting Your Phone

AstroHelm needs the rear camera to have a clear, unobstructed view of the sky in the same direction as your telescope. The mount must be rigid — any flex or play between the phone and the scope will shift your alignment every time you slew.

Caution

Do not rely on friction or tape. If the phone can shift even a fraction of a degree, plate solving will succeed but your pointing will be off.

MagSafe Mount

MagSafe phone mounts attach magnetically to the back of iPhone 12 and later. Many manufacturers sell MagSafe-compatible cold shoe adapters that also screw into a standard ¼-20 tripod thread. This makes them easy to attach to a telescope dovetail or camera body. If you would like to attach to the finder bracket, you can purchase a finder dovetail.

Note: if you have a case, it has to be compatible with MagSafe as well. Look for a ring of magnets.

Sample products:

• MagSafe Mount
  • Amazon (US): Neewer | Smallrig | Ulanzi
  • B&H: Leofoto | Smallrig
• Finder Dovetail
  • Amazon (US): Astromania | Generic | SVBONY

Clamp Mount

A universal phone clamp with a ¼-20 stud is a versatile option. The clamp grips the sides of the phone, and can be screwed directly into a dovetail plate.

Sample products:

• Clamp Mount with Cold Shoe and ¼-20 tripod thread
  • Amazon (US): Neewer | Ulanzi
  • B&H: Smallrig
• Clamp Mount with ¼-20 tripod thread
  • Amazon (US): Ulanzi

Dedicated Telescope Phone Mount

Several astronomy accessory makers sell mounts designed specifically to attach a phone to a telescope, typically to the finder bracket. Though common in China, these are hard to find in the western markets.

Mirrors and Diagonals

If you prefer to mount the phone parallel to your telescope or camera for easier viewing, you can place a mirror or diagonal in front of the rear camera. This redirects the camera’s field of view so it still points in the same direction as your main telescope.

When using a mirror or diagonal, the image seen by the camera may appear flipped horizontally or vertically. You will need to correct for this in AstroHelm so that plate solving works correctly. To check whether the image is flipped, point the camera at a sign with text — if the text appears mirrored, you need to enable the flip setting.

To invert the image, go to Finder → Camera → Flip Image.

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Smartphone Eyepiece Adapter

Eyepiece adapters hold the phone’s camera over the eyepiece so you can photograph through the telescope. AstroHelm does not support this configuration. The field of view is typically too small for plate solving to work.