Technology & formats
A heavy deck isn’t detailed. It’s just uncompressed.
The instinct that a big file means a high-quality presentation is exactly backwards. Deck weight is almost entirely images — and images are where the easy, invisible savings live.
5 min read
Jun 2026
Every claim sourced · 2 references
A 40 MB deck sounds impressive until you look at what's inside it: a couple of full-resolution phone photos, three screenshots pasted at their native size, and a "hero image" that's ten times larger than the slide it sits on. The text and layout weigh almost nothing. The bloat is all pixels you can't even see.
✕ The myth
"A big file means a rich, high-quality deck."
Heavier must mean more detailed, sharper, more professional.
✓ The reality
Weight is uncompressed images, not quality.
Right-size and compress the pictures and a deck routinely shrinks by an order of magnitude with no visible difference on screen.
Two moves do most of the work. First, right-size: export images at the resolution the screen actually shows (a Full-HD slide needs a Full-HD image, not a 48-megapixel original). Second, compress smartly: modern formats like WebP cut photo weight 25–34% versus JPEG at the same quality, by Google's own measurements.1 Do both and the "huge" deck becomes a light one that opens fast and flips instantly.
Why a light deck presents better
Lighter files open faster, transition without lurching, and travel more reliably over whatever network you're on. On the projector, none of the removed weight was ever visible — you deleted megapixels the screen couldn't display anyway. And keeping line-art, charts and logos as vectors (rather than giant PNGs) keeps them razor-sharp for almost no bytes at all.
Images
Almost all of a deck's weight — text and layout are negligible by comparison.
0%
Lighter: lossy WebP vs equivalent-quality JPEG (Google's measurement).
1
Right-size
Export images at the display's resolution, not the camera's.
⚖ The honest bit — don't over-compress
The goal is right-sized, not tiny.
Compression has a floor. A detailed chart you'll zoom into, a photograph that fills the wall, a medical or technical image where fine detail is the point — these legitimately need enough resolution, and crushing them produces visible artefacts that undercut your credibility. "Optimise" means matching the pixels to the screen, not racing to the smallest possible number. Vector for line-art, sensible raster for photos, and stop when it looks perfect on the target display.
Where SyncBy!App fits
SyncBy renders your slides to efficient images in the browser before sending them, so a right-sized PDF flies to the screen and flips instantly even on modest Wi-Fi. It rewards a well-optimised deck — but it isn't a licence to be sloppy: the sharper and better-sized your source, the better it looks on the wall. Garbage in is still garbage on a two-metre screen.
TL;DR
- Deck weight is almost entirely images, not "quality."
- Right-size to the display's resolution and compress (WebP is 25–34% lighter than JPEG).1
- Keep line-art as vectors — sharp for almost no bytes.
- Honest caveat: don't over-compress detail that matters; aim right-sized, not tiny.