Create Wiki · Redstone
Smart Observer
The Smart Observer is Create's take on the vanilla observer. Instead of reacting to any block change, it looks at what is in front of it and emits a redstone signal when it sees the item in its filter: in a chest, on a belt, inside a chute, in a pipe, or even as a placed block. It is the ideal sensor for counting, sorting or starting a machine at the right moment.
Quick facts
- Category
- Redstone
- What it sees
- Placed block, items on belts or depots, inventory contents, fluid in a pipe or tank, packages on a Chain Conveyor
- Filter
- An item or a filter; empty, it reacts to anything
- Signal
- On while it sees the item, then 6 ticks (0.3 s) after the last one
- Recipe
- 1 Electron Tube + 1 Brass Casing + 1 Observer
- Version
- Create 6.0.8 · Minecraft 1.21.1
Crafting table recipe
→ 1 Smart Observer
An observer that looks at contents
Place the Smart Observer facing a block and it reads its contents. In front of a chest, a barrel or an Item Vault, it turns on as soon as the inventory holds the item in its filter, and stays on as long as there is some. With an empty filter it reacts to any item: a "chest is not empty" detector.
Setting the filter
The filter sits on the side of the observer. Right-click it with an item to set it, or with a Create filter to target a list of items or an attribute. A single observer can then watch a whole family, for instance every raw ore, without any extra wiring.
Recognising a placed block
If there is no inventory in front of it, the observer compares the block itself with its filter. Set to amethyst, it turns on when an amethyst block appears in front of it. Perfect for a farm that must react when a crop has grown or when a stone generator has produced the right block.
Belts, chutes and pipes
Facing a Mechanical Belt or a Depot, it reacts to items passing through the centre of the watched segment. In front of a Chute it sees what goes through; in front of a pipe, the fluid flowing in it. Each passage gives a short pulse, enough to count items with a redstone counter.
With a funnel
A classic setup: a Funnel takes items out of a chest onto a belt, the observer watches further down the line and stops a machine or lights a lamp when the right item comes by. Because it has a filter, it only reacts to what matters and ignores the rest of the flow.
A signal that lasts just long enough
After the last item it saw, the signal stays on for 6 ticks, that is 0.3 seconds, then turns off. For an inventory it stays on continuously while the item is present. For a signal based on quantity rather than a simple yes or no, use the Threshold Switch.
Three useful setups
Stock alarm: an observer with no filter against a factory's output chest lights a lamp as soon as something is waiting to be collected. Emergency sorting: set to an unwanted item, it opens a trapdoor or switches a tunnel when that item passes on the main line. Production counter: facing the last segment of a belt and wired to a redstone counter, it gives the number of stacks produced. In each case the filter does the work that would otherwise take several comparators.
And packages
In the Create 6 package network, a Smart Observer facing a Chain Conveyor reacts to the packages looping around it when they match its filter; with a Package Filter, the address is what counts. It is used to signal a delivery or trigger unpacking.
Related pages
Sources for the numbers (Create 6.0.8 code)
- Detection: SmartObserverBlockEntity.tick (filtered block, TransportedItemStackHandlerBehaviour at the centre 0.45, FluidTransportBehaviour, ChainConveyorBlockEntity.getLoopingPackages, inventory, tank)
- Signal length: SmartObserverBlockEntity.DEFAULT_DELAY = 6 ticks
- Recipe: crafting/logistics/content_observer.json
- Scene: DetectorScenes.smartObserver; belt items simulated
Original texts and animations by Create France, rendered from the mod's Ponder scenes. Create is a mod by the Create Team, not affiliated with Create France.