Contact sheets without a scanner
Six frames on a light table, one phone photo, one invert — enough to decide which negatives are worth a proper scan. Faster than warming up a flatbed for a roll you may not use.
Browser tool · 6 modes · 0 uploads
Photo Negative
A photo negative reverses tone: what was lit is dark, what was dark is clear. This page makes one from any photo, and goes the other way for film scans.
Drop an image, paste it, or click to choose
JPG · PNG · WebP · GIF · BMP — decoded on this device, never uploaded
Mode
Intensity
Output
Nothing is uploaded
The bytes stay in the tab. Clear the network panel, then invert a photo: no request appears, because the work happens in page memory.
Full resolution
No 2 MP preview cap, no server-side resize. A 48 MP frame comes back at 48 MP.
Six modes, not one
Whole image, a single channel, skin-safe, or dialled back to any strength between 0 and 100%.
About
What this conversion actually does
A photographic negative is not merely an inverted picture. On film, the silver halide that was exposed turns dark, so the strip you hold is a record of light measured backwards. Inverting the colours of a digital photo reproduces the look, but not the material: the grain, the density range and — on colour film — the orange mask all come from the emulsion.
That mask is the single most common surprise. Scan a colour negative, invert it with any tool, and the result looks teal rather than neutral, because the film base already carries an orange cast that the inversion turns into its complement. The fix is a per-channel white balance after inverting, not a different invert button.
Specification
What it accepts, and what it returns
| Input formats | JPG, PNG, WebP, GIF (first frame), BMP, AVIF where the browser decodes it |
|---|---|
| Maximum size | No fixed cap. Tested to 8000 × 6000 (48 MP) on a machine with 8 GB of RAM |
| Speed | 1920 × 1080 in well under a second; 48 MP in about four seconds |
| Transparency | Alpha is never touched. PNG output keeps it, JPG output is flattened onto white |
| Output | PNG (lossless, alpha preserved) or JPG at quality 0.92 |
| Uploads | None. The file is read with the File API and drawn to a canvas that never leaves the page |
Modes
Six modes, and when each one is the right call
| Mode | What it does | When to use it |
|---|---|---|
| Full invert | 255 − value on R, G and B | A true negative. Also the base layer for duotone and print work. |
| Red channel only | R inverted, G and B untouched | Pushes the whole image toward cyan-green. One plate of a two-colour screen print. |
| Green channel only | G inverted, R and B untouched | Magenta shift. Good for testing how a muted palette reads in print. |
| Blue channel only | B inverted, R and G untouched | Yellow shift. Useful for warm/cool split toning without a curve tool. |
| Smart invert (keeps skin) | Skips pixels inside the skin-tone range | Portraits. Faces stay recognisable while the background turns into a negative. |
| Intensity 0–100% | Blends the negative with the original | Anything that needs a hint of the effect rather than a full inversion. |
Method
Three steps
Photograph the strip, or start from a scan
For a quick look at 35 mm, put the strip on a tablet at full white brightness and shoot it square-on. For anything worth keeping, use a real scanner — the light table will tint the result and dust will read as white specks after inversion.
Invert, then judge the cast
Full invert gives the positive. If it reads cyan or teal, that is the orange mask, not a bug. Correct it afterwards with per-channel levels: raise red, lower blue, and neutral grey comes back.
Export as PNG while you work
Correcting a cast on a JPEG means re-encoding twice. Keep the inverted frame as PNG until the colour is right, then save the final delivery copy as JPG.
Use cases
What people actually use it for
Previewing a lab order
If you are sending film out, a phone-and-invert preview tells you whether the frames are exposed the way you intended before you pay for scans.
Teaching exposure
A negative makes the Zone System visible: the dense areas are the highlights. Showing students the inverted and the positive side by side explains exposure faster than any chart.
Cyanotype and contact printing
Alternative processes want a negative the size of the final print. Invert a digital file, print it on transparency film, and the density range is close enough for a first test.
The analog look, digitally
Musicians and designers ask for "film negative" covers constantly. Invert, keep a little of the cast, add grain — the cast is what reads as analog rather than broken.
Checking old scans
Twenty-year-old scans often have a colour shift that is easier to see in the negative than in the positive. Invert, look at the neutrals, then correct the original.
Under the hood
Why a film negative is not just 255 − x
A digital invert assumes the image is a linear record of light. Film is not: density follows a curve, with a toe and a shoulder, and colour negative film adds an orange mask so that the three dye layers can be printed onto paper without crossed curves. Inverting a scan therefore inverts the mask as well, which produces the cyan cast.
The practical consequence: invert first, then neutralise. Pick a spot in the frame that should be grey — a road, a wall, a shirt — and adjust red and blue until it is. Everything else follows, because the mask is constant across the frame.
Questions
Answered plainly
Can I digitise film with this tool?
For a contact sheet, yes: photograph the strip on a bright white screen and invert. For a keeper, no — a phone photo brings dust, reflections and the screen’s colour temperature with it. Use a scanner and this tool only as a preview.
Why does my inverted scan look teal or cyan?
The orange mask. Colour negative film is manufactured with an orange base so the dyes print correctly; inverting turns orange into cyan. Neutralise afterwards by raising red and lowering blue until a known grey reads grey.
Does it work for black-and-white negatives?
That is the cleanest case. There is no mask and only one channel of information, so a straight invert gives a correct positive. Expect the contrast to look flat — negative film is low-contrast by design, and a curve restores it.
What about slide film?
Slides are already positive. Inverting one produces a negative-looking image rather than "recovering" anything, which is fine as a look but is not a restoration step.
Can it open RAW files from my camera?
No browser decodes CR2, NEF or ARW. Export a 16-bit TIFF or PNG from your converter first, then invert here — the file will still be full resolution.
Do I lose detail by inverting?
Not with PNG. Inversion is a lossless per-pixel subtraction, so the histogram is reversed exactly. Only JPEG output re-encodes, and only then does anything change.
What comes next
A server-side API and a desktop batch runner are planned. The browser tool above stays free and unlimited: no account, no watermark, no file cap.
Free, permanently
Full resolution, all six modes, batch and ZIP. If a page ever asks you to register to invert an image, it is not this one.
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