Roll Control Modes — Complete Guide¶
Flair offers five roll control modes that determine how the roll axis behaves during Cartesian (carts) moves. Choosing the right mode for your shot is one of the most important decisions you make before programming — the wrong mode can make a smooth roll move nearly impossible, or cause the rig to trip. This guide covers every mode, its pros and cons, and which situation each is designed for.
How to change the roll mode¶
There are two ways to switch roll mode:
- Right-click on the roll axis in the axis list and select a mode from the context menu.
- Use the drop-down menu in the Control side menu on the right of the Flair interface.
Change the roll mode before programming — changing it mid-job can produce unexpected behaviour.
Mode 1 — Roll Moves / Roll Independent¶
Also called: "Roll Moves" in the drop-down; "Roll Independent" in the axis selection context menu. They are the same mode.
In Roll Independent, the roll axis is treated as a fully independent axis. You can see the exact encoder value. There is no automatic horizon compensation.
Important warnings:
- If you try to use Carts control (e.g. Carts View) with a non-End-Mounted camera, Flair will warn you that carts control does not work well in this configuration.
- If the rig trips and roll changes to independent, or after a Goto Home, you will not be able to run a move in any form of Target Tracking.
- If the camera is set to End Mount, the warning will not appear but the roll still will not compensate to keep the camera level during a carts move.
Pros:
- Allows the roll axis to be programmed as fully independent — useful when the camera is optically centred on the roll axis (zero Y and Z Lens Nodal Offsets).
- Can produce interesting uncontrolled roll "sways" during a move if that is a creative intention.
Cons:
- Cannot use carts control properly.
- Programming a move is very difficult or impossible unless the camera is set to End Mount.
When to use Roll Independent:
Use on rigs where the head is always mechanically level — such as the Talos or Modula. These rigs do not need roll to compensate for a non-level head. It also works on a Milo if you select "Head Level" mode.
Mode 2 — Roll Level¶
Roll Level keeps the camera horizon level at all times. You cannot add deliberate roll motion while in this mode.
Critical limitation — the ±90° tilt singularity:
Roll Level cannot pass through straight up or straight down (±90° tilt). At this point Flair no longer knows where the horizon is and will attempt to flip the camera to find it — causing the rig to trip. Avoid this position entirely. It is also not possible to pass through this point while running a move.
Note: the ±90° tilt singularity here is distinct from the "Tilt −90° Rig Singularity" — they are completely different phenomena.
Pros:
- Camera is always in level.
Cons:
- Camera is always in level — you cannot add deliberate roll motion.
- Cannot correct a horizon that does not look straight.
- Cannot pass through ±90° tilt.
When to use Roll Level:
- When you need the camera to stay completely level throughout the entire move with no roll.
- As a recovery tool: if the rig trips and you lose level, or if you accidentally press roll in another mode, switch to Roll Level, perform a Goto, then switch back to your desired roll mode.
Mode 3 — Roll Relative¶
Roll Relative combines Roll Moves and Roll Level: the camera keeps level automatically as long as you do not intentionally move roll. The displayed roll value is relative to the camera's current level position — so a value of 180 means the camera is flipped upside down.
This is the default mode for most operators and most shots.
Pros:
- Camera stays level when you are not deliberately rolling.
- You can still roll the camera as much as you like.
- Very easy to create smooth roll motion.
- You can add specific key frames for the roll axis independently of other axes.
Cons:
- Cannot pass through ±90° tilt (same singularity as Roll Level).
When to use Roll Relative:
Use this as your default mode. In the words of the original guide: "In my eyes in >95% of the moves, Roll Relative is the best option." Always discuss with the director and DOP whether the move needs to pass through ±90° tilt. If it does, this mode will not work.
Important note on 180°/360° roll and hidden independent values (from Simon Wakley):
Be aware that +181° and −179° are the same physical position, and 360° is the same position as 0°. If you programme a move from 0 to 181 and run it, it will work. But if you then turn on Cart Control, Flair may think the camera is at −179°. When you store the point it may try to go the other way. Similarly at 360°, when you get to the end and turn Cart Control back on, Roll Relative may read 0. Watch for this and enter the correct value by hand when necessary.
When adding roll values in the numerics (especially for a 360° roll), it is possible that the rig wants to perform unintended gotos even if the framing looks correct. This is because of the "hidden" independent roll value. Check example videos on the forum topic for how to resolve this.
Tip — 180° roll trick (from Ben M):
The 180° roll trick also works with back-running. To programme a move where the camera starts flipped upside down and rolls 180° during a push-in: plot the two points using X camera in carts, then type 180 in roll on point 1. Back-run the move and store the position.
Mode 4 — Roll Up¶
Roll Up resolves the ±90° tilt singularity that affects Roll Level and Roll Relative. It defines roll orientation using a "Roll Up Node" — an additional path curve that always tells the roll axis where "up" is.
When you select Roll Up, three additional curve displays appear in the Graphical Carts view: X Up, Y Up, and Z Up. The Up Node is a path curve like the camera path or target path. Because of this extra reference, the rig can pass through straight up or straight down without tripping.
Pros:
- Can pass through ±90° tilt.
Cons:
- The camera does not automatically stay level — you must manage the Up Node manually.
- Making smooth roll motion is significantly more complex than in Roll Relative.
- On longer moves with many key frames, keeping the camera level requires substantial extra work.
When to use Roll Up:
Only use Roll Up when you must pass through ±90° tilt — for example, a top shot or a vertical circle around an object.
360° vs 180° roll in Roll Up — why it is more complex:
For a simple 360° roll push-in, Roll Relative needs only two key frames. In Roll Up you must add intermediate key frames because the Up Node stays on one side — just adding 360+ in the roll value will not produce visible roll motion unless the Up Node path is also animated correctly. The same issue applies to a 180° roll: in Roll Up a naive attempt will produce an instant flip at the midpoint where the Up Node crosses through the camera path. You must add additional intermediate key frames to guide the Up Node around the correct arc.
Mode 5 — Roll Adaptive¶
Flair Classic only
Roll Adaptive is currently only available in Flair Classic. It is not yet available in the Flair 7 GUI.
Roll Adaptive combines Roll Relative and Roll Up. You can switch between the two modes at any point within a single move, by setting values on a dedicated "roll mode" dummy axis configured in Kinematics Setup. A value of 0 = Roll Relative; a value of 1 = Roll Up. Between key frames, changing from 0 to 1 switches the roll mode mid-move.
Pros:
- All the advantages of Roll Relative and Roll Up, combined.
Cons:
- Advanced feature — difficult to use properly.
- Requires significant practice before use on set.
- Requires prior understanding of both Roll Relative and Roll Up.
Never test Roll Adaptive for the first time on set
This is a new and relatively untested feature. Always practise in a safe environment first. You must fully understand Roll Up and Roll Relative before attempting this mode.
When to use Roll Adaptive:
Extremely rare. Roll Relative or Roll Up will be a better solution in almost every case. Use Roll Adaptive only when you have a long, complex move with many key frames that must pass through ±90° tilt but where managing Roll Up across the entire move would be impractical. It requires a dummy axis configured in Kinematics Setup.
Decision Guide — Which mode should I use?¶
| Situation | Recommended mode |
|---|---|
| Standard rig (Milo, Talos, Modula with level head) | Roll Independent |
| Need level horizon, no deliberate roll | Roll Level |
| Most shots — level default, option to roll | Roll Relative (default) |
| Must pass through straight up or down | Roll Up |
| Complex move, mixed roll requirements (advanced) | Roll Adaptive (Classic only) |
The 95% rule: Roll Relative is the correct choice for the vast majority of shots. Only switch to another mode when there is a specific reason — singularity avoidance, level head rig, or creative effect.
Always ask the DOP and director before locking in a mode: if the move needs to go through ±90° tilt (straight up/down), you cannot use Roll Relative or Roll Level.
Related Issues¶
- Roll Past 180° / 360° — Robot Arm Unwinding
- Camera Orbital Roll-Up — Incompatible Move
- Roll Orbital and Flip Both — Combined Mode
- 360° Orbit / Roll-Up in Carts Mode
Source: How to use Roll Control Modes — Introduction · Roll Independent/Moves · Roll Level · Roll Relative · Roll Up · Roll Adaptive · Examples — talk.mrmoco.com