1 Your Task

Assume you are explaining a video of a scientific experiment to a grad student with visual impairment who cannot see the scene, but needs to know the critical steps. You should describe everything in a way that allows the student to reconstruct the experiment.

Your explanation should be complete, structured, and sequential, as if you are narrating what is happening in real time.

2 What to Include in Each Step

Walk the student through the procedure the same way you'd walk them through it in person. For every step, try to convey:

• What is being used: the instruments, containers, reagents, and samples involved. The first time something appears, briefly say what it is so the student can picture it (e.g., "a P200 micropipette," "a 1.5 mL microcentrifuge tube with a clear colorless liquid inside").
• What is being done: the action itself. Please use specific action verbs like pipettes, aspirates, dispenses, vortexes, inverts, decants, centrifuges, weighs, dissolves, transfers, incubates, rather than vague ones like uses, puts, or does. The student is relying on the verb to understand the motion, so "she vortexes the tube for 5 seconds" tells them much more than "she mixes it."
• Measurable values: any volumes, masses, concentrations, temperatures, durations, or speeds that are visible on screen, shown on a display, written on a label, or said out loud.
• Visible changes: color shifts, precipitation, bubbling, phase separation, dissolution, anything observable that signals something is happening.
• How things come together: how the tools and materials interact, e.g., "the tube is loaded into the centrifuge rotor and the lid is closed."

3 When You're Not Sure

Only describe what you can actually see in the video. Please don't fill things in from your own knowledge of how the protocol "should" go, even if you're confident. We want the annotation to reflect the video, not the textbook.

A few cases come up often:

• A parameter would normally be specified, but it is not visible in the video. Mark it as [Not Visible Parameter] where that value would appear in the sentence.

• Something is happening but you can't quite tell what. Mark [Not visible] in the step and describe what you can see.

• You can't confidently identify a reagent or instrument. Describe its observable properties instead of guessing the name.

4 Output Format

Each video is divided into segments (from the spreadsheet next to the file when available; otherwise fixed-length chunks). For every segment you complete the four panels on the right. In the downloaded or submitted JSON, that becomes one object per segment with (among other metadata) these fields:

• equipment: apparatus and instruments you see.
• materials: consumables, reagents, tubes, samples.
• steps: ordered strings, one per step box. In each step, give the time range within that segment and the moment (mm:ss) when the action occurs, then describe it (use clear verbs).
• visualized_results: observable outcomes (color, bands, precipitate, phases).

Optional Extra_Notes: Click the pink Extra Note button next to Replay at the exact moment you care about. A popup opens (same purple header as the Instructions window); the tool records the video time at that click and pauses playback. Type your remark and choose Save note. Entries belong to the current segment only. In JSON they appear under Extra_Notes: each key is a time string in m:ss form (for example "1:05"), and each key maps to a list of note strings. You can save multiple notes at the same timestamp or at many different times. Remove notes from the list inside the popup if needed.

Special labels (type them exactly so automated checks can find them):

• [Not visible]: this field might apply but you cannot clearly see the relevant detail, or (in Steps) the action is ambiguous. Say what you can see; in a step you may write [Not visible: adds a white powder from a spatula].
• N/A: this field does not apply to this segment.
• [Not Visible Parameter]: use in Steps when a number or unit belongs in the sentence but is not visible in the video (duration, rpm, temperature, volume, and similar). Put the tag exactly where that value would appear, as in section 3.

5 How This Tool Works

1. Each video uses a matching spreadsheet next to the MP4 (videos/<name>.xlsx or .csv) with start and end times in seconds per step; if neither file is present, the app uses fixed 30-second segments.
2. Watch a segment using the Play button.
3. Fill in Equipment, Materials, Steps (with times inside the segment when each part happens), and Visualized results.
4. Optional: the Extra Note button (pink, next to Replay) saves time-stamped text into Extra_Notes for the current segment (see Output Format).
5. Click Save (or simply move to the next segment, it auto-saves).
6. Repeat for every segment. Use the Video dropdown to switch between videos.
7. When finished: use Export JSON to download a copy of your work. To submit to the project, click Done. Submit Annotations under the sidebar (confirm in the dialog). It uploads your JSON and notifies the lead; follow whichever method your coordinator asked for.