Photographing a document and converting it to PDF is one of the most common tasks there is: a signed form, a receipt for expenses, a passport page for a visa application. It also fails in predictable ways, with content cropped at the edge, a page that prints at the wrong size, or text too blurry to read.
Four settings decide the outcome.
Page size
Match image makes each PDF page exactly the dimensions of its image. Nothing is cropped, nothing is padded, and there is no whitespace. This is right when the PDF is for viewing on a screen: a photo album, a set of screenshots, anything nobody will print.
US Letter (612 × 792 points) is the standard in the United States and Canada. A4 (595.28 × 841.89 points) is the standard essentially everywhere else.
Choose a fixed size when the document will be printed, or submitted to a system that expects a standard page. Your image is scaled to fit within the page, preserving its aspect ratio, with the remainder as white margin.
Avoid sending an A4 PDF to a US recipient, or Letter to a European one. The two are close enough that it prints, and different enough that it either crops the edges or leaves an odd band of white. If you know where it is going, match it.
Orientation
Auto picks per image: a landscape photo gets a landscape page, and a portrait one a portrait page. For a mixed batch this is almost always what you want.
Portrait or Landscape forces every page one way, which matters when the PDF must be consistent, such as a report where every page should be the same shape or a document going into a binder.
If you force an orientation that fights the image, the image is scaled to fit and you get large white bands on two sides. That is the cost of consistency and no bug.
Margins
None runs the image to the page edge. It is correct for photo pages and for anything where the image is the page.
Normal (36 points, half an inch) is the sensible default for documents. It gives the content breathing room and, importantly, keeps it clear of the physical limits of a printer.
Wide (64 points, about 0.9 inches) leaves room for hole-punching, binding or annotation.
The practical argument for margins is that most printers cannot print to the edge. Consumer inkjets and office lasers have an unprintable border, typically a quarter of an inch. A PDF with zero margins sent to such a printer either gets scaled down slightly, changing every dimension on the page, or has its edges clipped. If a document will be printed, give it margins.
Resolution, which the settings cannot fix
This one is decided before the conversion, when you take the photograph.
PDF pages are measured in points at 72 to the inch, but the image inside the page has its own pixel count, and the ratio between them is your effective print resolution.
Rough guidance:
| Use | Effective DPI | Pixels for a Letter page |
|---|---|---|
| Screen viewing only | 72-150 | 600 × 800 |
| Ordinary document printing | 200-300 | 1700 × 2200 |
| Archival or high-quality print | 300-600 | 2550 × 3300 |
A modern phone camera at 12 megapixels produces roughly 4000 × 3000 pixels, which is comfortably more than enough for a full-page document at 300 DPI. Resolution is rarely the problem. The problems are focus, lighting and angle.
No converter can add detail that was not captured. Scaling a small blurry image onto a large page produces a large blurry image.
Photographing a document properly
Most bad document scans are bad photographs, and the fixes are simple:
- Use a flat surface and good light. A window during the day beats any indoor bulb. Avoid direct overhead light, which produces glare.
- Shoot straight down. An angled photo produces keystoning, a trapezoid instead of a rectangle, that no conversion setting corrects.
- Avoid your own shadow. Stand so the light comes past you and not through you.
- Fill the frame with the document, but leave a small border so nothing is clipped.
- Tap to focus on the text and check it before moving on.
- Use your phone’s document scan mode if it has one. Both iOS Notes and Google Drive include one, and they correct perspective and contrast automatically, which is genuinely better than a raw photograph.
File size, and what drives it
Image PDFs are large because photographs are large. A 12-megapixel photo is 3-5 MB, so twenty pages is 60-100 MB.
If a submission system has a size limit:
- Resize the images first, to around 2000 pixels on the long edge. That is ample for a printed page and cuts file size dramatically.
- Convert photos to JPEG, since PNG is lossless and enormous for photographic content.
- Use your phone’s scan mode, which typically produces far smaller files than a raw camera photo.
- Split the document into several PDFs if the limit is hard. The split tool does this without uploading anything.
Batch order
Files are converted in the order they are listed, so name them to sort correctly. Use
zero-padded numbers (page-01.jpg, page-02.jpg), because without padding page-10 sorts
before page-2 in most systems, and your twenty-page contract arrives shuffled.
If pages do come out in the wrong order, the organize tool reorders an existing PDF without re-converting.
The checklist
- Printing it? Choose Letter or A4 to match the destination. Screen only? Match image.
- Mixed shapes? Auto orientation.
- Printing it? Normal margins at minimum, because printers cannot reach the edge.
- Photograph it properly: flat, lit, straight down, in focus.
- Name files with zero-padded numbers so the batch sorts correctly.
- Check page one and the last page before sending.
Convert at JPG to PDF, PNG to PDF or WebP to PDF, all in your browser with nothing uploaded. If it is going on paper, how to get a document printed covers the rest.