A phone camera is a perfectly good substitute for a scanner here, as long as you handle the two things that go wrong: the paper photographs grey rather than white, and thin ink disappears when the image is scaled down.
Sign it properly first
Before the camera comes into it:
- Plain white unruled paper. Not a ruled page, not a form.
- Black ink, or blue if your notification allows it. A gel or ballpoint pen, not a fine liner — thin strokes vanish at 140 x 60 pixels.
- Running handwriting. Capitals are rejected. See signature rules.
- Natural size, around 4 to 5 cm wide.
- Sign it several times on the same sheet and pick the best.
Photographing it
Flat surface, good light. A table near a window. Indirect daylight is ideal.
Phone directly above, parallel to the paper. Looking down at an angle makes the signature a trapezoid rather than a rectangle, and correcting that later costs sharpness. Line the paper edges up with the edges of your screen.
Watch your own shadow. Standing over a page puts your shadow on it. Position yourself so the light comes past you, not through you. If the page has a visible gradient from bright to dark, move.
No flash. It produces a hot spot in the middle, a hard shadow at the pen strokes, and glossy reflections off wet-looking ink.
Fill the frame. The signature and a small margin, nothing else. Every pixel spent on the table around it is a pixel not spent on the ink.
Tap to focus on the signature before shooting. Phones often focus on the paper texture or the background instead.
The grey paper problem
Your photo will look grey, not white. This is not a mistake you made — the camera meters for the average brightness of the scene, and a page that is mostly white gets pulled down toward mid-grey.
This is what the background clean-up slider in our resizer fixes. It maps everything above a brightness threshold to pure white and deepens what is left, using a soft ramp so the edges of the strokes keep their anti-aliasing instead of turning jagged.
Turn it on for any signature — it is on by default when you select a signature upload — and adjust:
- Too low and grey paper survives as a dirty background
- Too high and thin parts of the strokes are erased, breaking the signature into fragments
Move it up until the background is clean, then back off slightly. Watch the strokes, not the background.
Cropping
Use Trim blank space to snap the frame to the ink automatically. It finds the bounding box of everything that is not white and fits it to your target dimensions with a small margin.
Then check the edges. A signature touching the frame edge may be cut off at the portal, and our pre-flight check warns about this. Zoom out slightly if it does.
The file will be too small
Expect it. A signature is mostly one flat colour and compresses down to 2 or 3 KB, well under the 4, 10 or 20 KB floor most portals set.
Our tool lifts it over the floor by appending blank comment data that decoders ignore — the image is not altered at all. It tells you how much it added. Why portals reject files that are too small explains why this matters and why some tools handle it badly.
If you genuinely cannot photograph one
There is a signature pad on the signature tab of every exam page — draw with a finger or a stylus.
Use it only as a fallback. Boards compare your uploaded signature against the one you write on exam day, and a finger-drawn signature usually looks different enough from your pen signature to raise a question. Paper and a camera is the better route whenever it is available.