Secondary images — the five jobs, the order, the gallery.

The main image earns the click on the search results page; the secondary images keep the shopper on the detail page and convert the visit into an add-to-cart. Amazon gives you six image slots in most categories — seven in some, nine in Brand-Registered listings with a video slot enabled. Treat the slots as a deliberate five-frame story-board, not as a dumping ground for "more product shots from different angles". A listing with six well-chosen secondaries consistently outperforms one with six redundant studio shots by 2–5% on conversion in our audits, and the gap widens on mobile where the gallery is the dominant scroll surface.

The five jobs every gallery has to cover

1. Lifestyle. The product in the situation it's actually used in — kitchen, bathroom, garden, gym, office. Sells the desired outcome and the aspiration, not the SKU. The lifestyle shot answers the silent shopper question "is this for someone like me?".
2. Infographic / feature callout. The 3–5 hard features overlaid on a clean product shot: dimensions, material, capacity, certifications, key technology. Carries the rational reassurance after the emotional lifestyle hook.
3. Scale. The product next to a hand, a body part, a coin, a piece of furniture, or any recognisable reference object. Shoppers chronically misjudge size from a hero shot on a white background, and a missing scale shot is the single biggest driver of size-related returns and one-star reviews complaining the item is "smaller than expected".
4. Comparison. Your variant matrix, your size chart, your "what's in the box" layout, or your product-vs-competitor positioning. Pre-empts the comparison the shopper would otherwise do by leaving the page.
5. In-use detail. The macro close-up that proves quality — stitching, finish, mechanism, texture, weave, material grain. Answers the "is this cheap or premium?" question shoppers ask but never type into a question box.

Every category needs all five jobs covered, even if the relative emphasis shifts. Apparel leans hard on lifestyle and scale; electronics lean on infographic and in-use detail; consumables lean on comparison and ingredient detail. Run your gallery against the five-job checklist and any missing job is a known conversion leak.

The order that converts

The mobile gallery shows images one at a time, swipe by swipe. Roughly 80% of mobile shoppers view the first three secondaries; under 30% reach image five. Desktop is more forgiving — the thumbnail strip lets the shopper jump — but the same front-loaded bias holds. Recommended order:

1. Hero lifestyle — the aspirational shot in the use environment.
2. Feature infographic — the rational reassurance immediately after the emotional hook.
3. Scale shot — answers the size question before the shopper leaves to measure.
4. Comparison or "what's in the box" — pre-empts the cross-shop.
5. Detail close-up — proves the quality for the shopper who scrolls.
6. Optional second lifestyle in a different context — broadens the addressable use-case.
7. Optional video slot (slot 7, Brand-Registered only) — covered in Episode 05.

Resolution, format, and the zoom threshold

• Minimum resolution: 1000 × 1000 px to be accepted, but upload at 1600 × 1600 px or larger to enable Amazon's hover-to-zoom feature on desktop. Zoom is one of the highest-engagement interactions on the PDP and the lift is meaningful.
• Aspect ratio: 1:1 square is the safe default. Other ratios get letterboxed and you lose pixels and visual weight.
• File format: JPG for photography (smaller files, faster mobile load), PNG when you need transparency or sharp text overlay on an infographic.
• Colour profile: sRGB, 72 DPI minimum. CMYK uploads render with shifted colour and look amateur.
• Background freedom: unlike the main image, secondaries can have any background — coloured, lifestyle, infographic, dark. Use that freedom; six white-background shots is a wasted gallery.

Infographic text — the size mistake that kills mobile

The most common infographic failure is text that's readable in the Photoshop preview at desktop scale and completely illegible on mobile. The mobile gallery renders secondaries at roughly 380px wide on a typical 6-inch phone. Text that's smaller than the equivalent of 24pt at full 1600×1600 output becomes a grey blur on mobile. Rule of thumb: if you can't read the infographic callout while holding the phone at arm's length, the callout doesn't exist for the majority of your traffic. Pull infographic copy ruthlessly — three callouts at 32pt beat seven callouts at 18pt.

Mobile-gallery quirks worth designing around

• The mobile gallery autoplays the first image as a hero card; image 2 onward requires a swipe. The transition from main to secondary 1 is the highest-attrition step in the entire gallery — make secondary 1 visually distinct from the main image so the swipe feels rewarded.
• Pinch-to-zoom on mobile works on individual images but resets the gallery position on exit. Shoppers who zoom an early image often don't make it back to image 5.
• The video tile (when present) renders inline at slot 7 on desktop but is promoted to a separate "Videos" carousel on mobile, often below the bullets — meaning a missing in-gallery video is less penalising on mobile than on desktop.

Seller vs Vendor — same gallery, different upload paths

Sellers upload secondaries directly through Seller Central or via the SP-API productImages feed, with changes typically live within minutes. Vendors upload through Vendor Central's image manager or by attaching assets to the NIS (New Item Setup) form, with longer moderation cycles (24–72 hours typical) and the catalogue team able to override your gallery without notice — especially during major catalogue overhauls. Brand-Registered sellers can lock down image contributors in Brand Registry → Manage Contributors, which is the only reliable defence against an unrelated catalogue contributor pushing a low-quality image into your gallery.

Failure modes that recur

• Six versions of the main image at slightly different angles. Looks thorough, adds zero new information, leaves all five jobs uncovered.
• No scale shot. Returns rate spikes, reviews complain about size, and the listing eats the cost of every return-shipping label.
• Infographic text under 24pt-equivalent. Unreadable on mobile, where 60%+ of traffic sits.
• Comparison shot that points to a competitor. Sends shoppers off your PDP to validate the comparison. Compare against your own variants, not against competitor SKUs.
• Lifestyle shot in the wrong demographic. A premium kitchen tool photographed in a student dorm reads as cheap; a budget tool photographed in a designer kitchen reads as overpriced. Match the lifestyle to the price point.
• White-background shots in slots 4–6. The gallery should escalate visual variety as it progresses; white backgrounds late in the sequence read as filler.

What to take into the next episode

Secondary images carry the visual story. The next episode covers the video slot — when a product video clears its production cost, the format Amazon's gallery actually surfaces, and the categories where a missing video is now a competitive disadvantage.