3ds max camera has two circles.

The three safety boxes in max correspond to each other.

External operational safety zone

Medium-sized title safety zone

Li- user safety zone

Active area (the largest yellow area)-This area will be rendered regardless of the aspect ratio or size of the viewport.

Action Safe Area (blue)-It is safe to include rendering actions in this area. The Lock check box locks the aspect ratio of the action box. When Lock is on, use the Both spinner to set the percentage of the active area that is trimmed in the Safe box. When Lock is off, you can set these parameters separately using the horizontal and vertical spinners. The default setting is 10%.

Title Safe Area (yellow)-It is safe to include titles or other information in this area. When used correctly, this area is smaller than the action box. The Lock check box locks the aspect ratio of the title box. When Lock is on, use the Both spinner to set the percentage size of the title box related to the action box. When Lock is off, you can set these parameters separately using the horizontal and vertical spinners. The default setting for the active area is 20%.

User Security Zone (purple)-Displays additional security boxes that can be used for any custom requirements. The Lock check box locks the aspect ratio of the user frame. When Lock is on, use the Both spinner to set the percentage size of the user box related to the action box. When Lock is off, you can set these parameters separately using the horizontal and vertical spinners. The default setting for the active area is 20%.

Hope useful to you