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Old School RuneScape

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Complete the Old School RuneScape Observatory quest. Fix the Professor's telescope by gathering planks, bronze, and molten glass.

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Complete the Old School RuneScape Observatory quest. Fix the Professor's telescope by gathering planks, bronze, and molten glass.

Walkthrough
  1. 1
    Go to the observatory and talk to the Professor. Agree to help fix his telescope.
  2. 2
    Gather 3 planks from the Barbarian outpost, east of Ardougne, near the building.
  3. 3
    Obtain a bronze bar. Travel to Port Khazard (south of Ardougne) to mine tin and copper, then take them to Ardougne to use the furnace.
  4. 4
    Go to the Port of Sarim with a bucket.
  5. 5
    Take the ship to Entrana, head east, and cross the bridge. Find seaweed west of the bridge and pick one up.
  6. 6
    Use the seaweed in the range north of the ship on Entrana to get soda ash.
  7. 7
    Use your bucket on the sand north of the ship to get a bucket of sand.
  8. 8
    Use the sand or soda ash with the furnace north of the ship to create molten glass.
  9. 9
    Return to the mainland. Go to the nearest bank, withdraw weapons, armor, and one cure poison potion. Travel back to the observatory.
  10. 10
    Talk to the Professor again. He needs the Lens Mould. Head down the ladder in the building.
  11. 11
    Navigate the dungeon maze. Avoid aggressive level 19 goblins. Most chests contain poison spiders. The chest directly southeast of the ladder contains one cure poison potion.
  12. 12
    Travel east, then south, then as far west as possible to find a chest containing the prison key. Do not open any other chests.
  13. 13
    Return east and north, then a little west and south to find the room with the lens.
  14. 14
    A level 48 guard will attack when you try to open the door. Kill the guard and use the prison key on the gate.
  15. 15
    Search the sacks to find the lens. Exit the room and head west to find the ladder to leave the dungeon.
  16. 16
    Talk to the Professor. Use the lens with the molten glass to craft the lens.
  17. 17
    Talk to the Professor again and meet him at the telescope on top of the hill next to the observatory building.
  18. 18
    Go back down the ladder and into the dungeon. Travel east, then south, then west to find a second ladder. Climb up.
  19. 19
    Talk to the Professor. Use the telescope. A window with a constellation will appear. Close the window.
  20. 20
    Talk to the Professor again to complete the quest. To return to the observatory building, travel back through the dungeon.
Tips
  • It is much easier to have all required items (planks, bronze bar, molten glass) before starting the quest.
  • Bring your own cure poison potion as the one in the dungeon may not be found immediately.
  • Deposit all armor and weapons before going to Port of Sarim for molten glass.
  • Withdraw necessary weapons and armor before returning to the observatory after getting molten glass.
  • The chest with the prison key is the only one you should open in the dungeon.

Guaranteed award plus a unique reward based on the constellation seen:

  • Aries: Attack experience
  • Capricorn: Strength experience
  • Virgo: Defense experience
  • Cancer: Emerald Amulet of Protection
  • Taurus: Super Strength Potion
  • Leo: Hits experience
  • Sagittarius: Maple Longbow
  • Pisces: 3 Cooked Tunas
  • Gemini: Black 2-Handed Sword
  • Scorpio: Weapon Poison
  • Aquarius: 25 Water Runes
  • Libra: 3 Law Runes

After the quest, click on the Observatory Assistant for a one-time wine reward. Locate the Spirit of Scorpius north of the reception area to get the mold for creating Unholy Symbols.

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