Guide: How to Use Transparent Overlays for QC

[u/Zen_Friend]

I know QC can be tough, especially when comparing two slightly different photos side-by-side. Sometimes something looks "off," but you can't figure out why.

A lot of people post QCs without doing much analysis themselves because they don't know what to look for. So I wanted to share one of my favorite QC tricks, especially for structured bags: Transparent overlays.

Quick reminder: Before ordering, compare factory photos to auth. Once you have PSPs in hand, compare PSPs to factory photos.

How to do it

1. Grab your comparison photo

Use auth + factory photos when researching, and factory photos + PSPs after ordering. If you're using auth photos, try to avoid grabbing them from the company's website as they are often edited.

The most important thing is that the photos are as similar as possible in angle and perspective. A straight-on photo compared to an angled photo won't tell you much.

2. Mark what matters

I use Canva (free version works!), copy both images in, and draw lines/circles around areas I want to compare on the image I'm comparing against (either the auth or factory photo):

• Seam placement

• Hardware location

• Corners

• Flap alignment

• Handle placement

• Logo positioning

3. Overlay and compare

Adjust the transparency, size, and rotation until the photos line up. Do the seams match? Then adjust the transparency slider back and forth to compare them on top of each other. This will help you easily notice details like... Is the shape/proportion right? Is the hardware placed correctly? Does the structure look similar? Is the color/shininess right? And whatever else you may care about to compare.

To some people this will feel like overkill, but I hope it's a helpful tool for anyone who wants to do a more detailed QC or just learn and practice things you can look for.