What is the Opt-Out cap?

The Opt-Out Cap is a tool for facial recognition obfuscation, taking the form of a baseball cap with concealed panels that can be deployed to block the wearer from being identified via massed facial recognition systems.

When used, the printed panels block the face of the wearer while displaying an alternative face, allowing for the user to disengage with the collection system without being automatically flagged as blocking their face.

The following instruction will cover how to assemble the Opt-Out Cap.

To assemble the Opt-Out Cap, you’ll need the following materials:

Where to Source – Big-Box Stores, Online, Thrift Stores

Alternatives – Any hat with a brim, beanies.

Notes - Any hat with a brim will work best for the cap, as it will also serve to partially block the view of overhead cameras. Caps with recognizable logos or flashy colors should be avoided, as these will serve as points of reference for further identification. The exception to that is a hat that is exceedingly common in the intended area of use, such as a cap with the logo for a local sports team or for the city.

Link - Ebay

PowerMesh — 2 - Power Mesh

9” x 12” (About 230mm x 305mm)
$12 / Yard

Where to Source – Fabric / Craft Stores, Online

Alternatives – Mosquito netting.

Notes – After testing various sorts of available readily available meshes, Power Mesh was found to work the best for The Opt-Out Cap. Its stretch and relative transparency work well with the transfer sheets. Mosquito netting can work, but is very transparent and may react badly to overheating during the application of the transfer sheet. 1 yard of power mesh at 60” cloth width is enough material to make 12 caps, so buy a quarter yard if possible.

Product Links - Seattle Fabrics, Joann

More info on power mesh - Hunker

Where to Source – Fabric / Craft Stores, Online

Alternatives – Non-Stretch Transfer Sheets, Textile Printing Service.

Notes – Transfer sheets are commonly used for applying graphics to T-Shirts and other textiles, and come in a variety of different types. The main 2 distinctions are whether they’re printed on an inkjet or laser printer, and whether the transfer will be applied to a material that is light or dark. When tested, the stretchable transfer sheets worked best on the Power Mesh, and retained the most detail of all the options tested while not warping the mesh. An alternative to printing yourself is to purchase the prints from a textile printing service. Typically these services use specialized techniques (Such as dye sublimation) to print directly onto textiles.

Product Links - Ebay, Avery

Video Tutorial - YouTube

You’ll also need the following tools for assembly:

1 - Color Printer Inkjet or Laser

Image by Jphill19 [CC BY-SA 4.0 ]

Notes – Select your transfer sheet type based off of the type of printer most available to you. Color printing drastically improves the quality of the finished digital print, so use it if possible. Assumed in this tool is a computer available that can output to

ClothingIron — 2 - Household Clothing Iron

Able to reach 380°F

Alternatives – Textiles Heated Press.

Notes – Most transfer sheets require an iron to be heated to around 380°F (about 194°C) to transfer well onto textiles. Most irons will be able to reach this temperature readily, but a good metric is an iron that consumes 1400 watts of power or more.

Alternatives – Textiles Roller-Cutter, A Sharp Knife

Notes – As power mesh is relatively difficult to cut cleanly textiles scissors will provide the best results, second only to a textiles roller cutter.

Alternatives – Sewing Machine, Paper Stapler.

Notes – Thread color isn’t important, and due to the low stress on the panels themselves, any standard thread will work. If available, a sewing machine could work for this purpose, but there’s relatively little sewing involved in the construction. If sewing isn’t an option, a common office paper stapler can be used to affix the printed panels to the cap in a pinch.

The following tools are optional, but makes the process much easier and cleaner:

Clean Construction Paper or card-stock slightly larger than the section of mesh to print onto. Used as an interlayer between your work surface and the power mesh when ironing.

PTFE / Teflon Paper, used to set the print transfer after the the transfer is applied.

Upon assembling the required tools and materials, follow these steps to make the Opt-Out Cap.

1. Print the Face Graphic onto the Heat Transfer Paper.

Load the transfer paper into the printer.

Make sure to load the transfer paper oriented correctly for the direction the printer prints in.

Print the face graphic.

Print at 100% scale for US Letter Paper (8.5” x 11”)
Print in color at the highest resolution (DPI) available.
It is suggested that you do a test print on normal paper prior to using the transfer paper.

Face Graphics and Templates are available here - Link (ZIP, 13.8 MB) - as well as at the bottom of this page.

When in doubt, follow the instructions on the Heat Transfer Paper for best results.

2. Pre-Heat the Iron and lay out the Transfer Paper onto the Mesh.

Power on the iron and set the temperature.

Set the iron to the temperature recommended by the transfer paper selected.
If the iron has no temperature readout set to the Cotton setting.

Lay out the mesh onto a flat and hard work surface.

DO NOT USE AN IRONING BOARD, they are cushioned and uneven which can cause warping of the graphic transfer.
(Optional) Put a piece of construction paper or card stock between your work surface and the mesh. When the graphic is pressed onto the mesh, it can sometimes reach through the meshes holes and leave residue on the work surface.
Make sure to lay out the mesh flat and un-stretched, otherwise the graphics to the mesh will be distorted after transfer.
Not all work surfaces can handle the temperatures of the iron.

Center the transfer sheet on the mesh face down.

Make sure the transfer sheet is flat against the mesh.

3. Use the heated Iron to transfer the Graphic to the Mesh.

Apply the iron to the center of the back of the transfer paper

Do not hold it in any one spot for too long

Working out from the center, move the iron around to every spot on the back of the transfer paper.

Follow the instructions for the transfer paper for the length of time to do so. When in doubt, 3 minutes is a good amount.

Allow the transfer to slightly cool, then peel the backer of the transfer paper off the mesh to expose the applied graphic.

The transfer of the graphic to the mesh may have filled in some of the holes in the mesh. To fix, stretch the mesh in every direction to open the holes up again.

The face graphic may be slightly warped at this point after stretching, but will even out over time or after an optional setting press.

4. Cut out the Graphics Panels from the Leftover Mesh.

Using scissors, cut along the dotted line along the outside of the printed area, removing any white area left over.

Cut along the 2 dotted lines between the 3 panels to separate the panels.

At this point in the process, you should have 3 panels labeled Left, Right, and Center, each showing a different area of a face.

5. (Optional) Set the Print and flatten the Panels.

When the mesh is cut into the panels, some of the internal stresses applied by the transfer paper transfer will cause the mesh to warp and curl slightly.

To fix, iron the flattened panels printed face up and using a heat-resistant anti-stick paper (Such as PTFE / Teflon paper) as a layer between the iron and the printed mesh.

Follow the same guides as used in step 2 for setting up this step.

6. Attach the Printed Panels to the inside of the Hat.

Position the CENTER panel to be aligned with the center of the sweat band in the interior of the baseball cap.

Make sure that the print is facing out, towards the bill of the cap.

Using a needle and thread, use small stiches to sew along the top of the panel to attach to the sweat band of the baseball cap. Sew along the full width of where the printed panel contacts the sweat band.

Alternatively, use an office stapler in place of the needle and thread. This has the advantage of not relying on any pre-existing sewing skills, but the metal staples be uncomfortable against forehead if the hat is too tight.

Do the same for the LEFT and RIGHT panels, aligning the long sides of each to the outside edges of the CENTER panel.

Done.

How to make your own Face Graphic.

Although this guide includes 2 distinct face graphics - Link (ZIP, 13.8 MB) - they may not suit your use case or preferences to display. If this is the case, follow these instructions on how to make your own. Note: These steps require a computer and some mid-level knowledge on how to produce digital graphics. Please use only the visages of public figures or individuals that have consented to this process.

Import the OptOutCap_PrintTemplate_Blank.pdf into your photo editor of choice.
Select 2 photos of the face of the person that will be represented on the printed panels on the cap.
- These photos should be relatively high resolution (at least 1000px x 1000px) and have similar lighting in both shots.
- One photo (used for the center) should be a straight on portrait of the person showing their full face, the second photo should be of the same person at a 3/4 view (Turned about 45 degrees from facing the camera).
Align the front facing portrait photo to the layer underneath the CENTER panel outline.
- Position the center line of eyes 1/3rd of the way down panel, and scale the photo so that the face fills the frame.
  Final positioning should place the eyes at the line distinguishing the top 1/3rd from the center, with the pupils of the eyes just inside the visible edge of the center template. The mouth should land somewhere in the bottom 1/3rd, with the nose in the middle.
  Crop or mask the portrait image to only appear within the center panel area.
Align the 3/4 view portrait to the layer underneath either the LEFT or RIGHT Panel.
- Scale and position the 3/4 photo as needed to align with photo within the center panel.
- Some color correction may be needed to account for the differences in lighting and contrast.
- Crop or mask the 3/4 portrait image to only appear within the center panel area.
Duplicate Mirror the image used in step 4 and place it in the yet unused panel.
1. Follow the steps in Step 4

If in doubt, use one of the premade face templates as reference.

Files -

Assembly guide without photos can be downloaded here - Link (PDF, 679 KB).

Assembly guide without photos as images (no PDF reader needed) - Link (ZIP, 2.1 MB).

High resolution Face Template + 2 Premade Face Graphics - Link (ZIP, 13.8 MB).

Revisions -

2019-11-05 - Published

If you enjoyed this post, please consider supporting my work via donation. It helps me keep everything open source…

Blog

The Opt-Out Cap, detailed assembly with photos.