FlipMyFormat

Cross Process: Develop a Photo in the Wrong Chemistry

Three separate channel curves, the way the real thing works, with the actual lookup tables drawn on screen. Where a curve leaves the bottom corner, that channel is filling your shadows with its colour.

Three separate channel curvesLive curve displayLive before and afterBatch + ZIP downloadNever uploaded

Drop images here

or click to browse · or paste with Ctrl+V

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Chemistry

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Lifts the foot of one channel, which is what fills the shadows with colour. It is the single most recognisable part of the look.

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The three channel curves

These are the actual lookup tables being applied. Where a curve starts above the bottom left corner, that channel is filling your shadows.

Presets

92

Your photos are never uploaded. The channel curves and the export both run inside this browser tab.

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Everything this tool does

Three curves, not one

Each channel gets its own contrast and its own shadow lift, because that is what the wrong chemistry does to three different dye layers. At the default settings they diverge by up to 44 levels between red and blue, which is colour separation rather than a cast.

The real lookup tables, drawn live

The graph shows the actual red, green and blue tables being applied, redrawn as you drag, with the identity line behind them. Where a line leaves the bottom corner, that channel is filling your shadows.

Shadow lift as its own control

Feeding pure black through the default curves gives 2, 6, 29, a blue shadow floor rather than black. With the lift at zero the same input comes back as 0, 0, 0.

No channel can invert

All three tables are built from monotonic pieces. Checked across every setting the sliders allow, no table decreases at any step in any channel.

Both directions of the process

Slide in negative chemistry gives the familiar cyan shadows; negative in slide chemistry gives a rarer warm-shadowed version with a heavy blue curve.

Strength and contrast separately

How far the channels diverge and how hard the overall curve is are different questions, so they are different sliders.

Drag to compare

Before and after share one frame with a slider between them.

Six purpose-built presets

Classic xpro, extreme, subtle, warm direction, contrast only and faded.

Batch with one ZIP

Apply one process across a whole set and take everything as a single archive built in your browser.

Nothing is uploaded

No server, no queue, nothing to delete afterwards. Close the tab and every trace of the image goes with it.

What each control does

Cross processing is three curves, not one. Each channel gets its own contrast and its own shadow lift, and the difference between those three is where the whole look comes from.

SettingWhat it doesTryGood for
Slide in negativecyan shadows, hard redlift 25-40The familiar xpro look
Negative in slidewarm shadows, blue curvelift 20-35A rarer, warmer version
Strength 30-50restrainedlift 15-25Subtle film feel
Strength 80-100extreme, obviouslift 30-50Poster and album art
Lift 0shadows stay blackany strengthContrast only
Lift 30-60shadows fill with colouranyThe signature of the look
Extra contrast 40-80harder curves on all threestrength 60+Graphic, punchy

3

independent channel curves

256

entries per channel

0

files uploaded

Live

curve display

ZIP

batch download

Free

no account needed

FlipMyFormat vs other cross process filters

CapabilityFlipMyFormatTypical free tool
Files stay in your browser
Three genuinely separate channel curves
Live display of the actual lookup tables
Shadow lift as its own control
Both directions of the process
Batch ZIP download without paying
No watermark on the output

How to cross process on purpose

Cross processing was a mistake before it was a technique. Colour slide film and colour negative film need different chemistry, and putting one through the other's process produces a picture with wildly wrong colour, crushed or lifted blacks and enormous contrast. Photographers noticed the results were interesting and started doing it deliberately, and by the 1990s it was everywhere in fashion and music photography. What makes it worth understanding rather than just applying is that the distortion is not uniform: each colour layer in the film responds differently to the wrong developer, so the three channels end up with three genuinely different tone curves. That is why cross processing does not look like a colour cast, which affects everything equally, and why it cannot be reproduced with a saturation slider. In practice the two controls that matter are the direction and the shadow lift. The direction decides which channel gets the hardest curve and which one loses its foot, and those two facts produce either the familiar cyan-shadowed version or the rarer warm one. The shadow lift is the signature. When a channel's curve no longer starts at zero, the darkest parts of your photograph can never be black again; they fill with that channel's colour instead. That single property is what people recognise, more than the contrast or the saturation, and turning the lift to zero gives you a punchy contrasty photograph that nobody would call cross processed.

  1. 1

    Add your photos

    Drag them in, click to browse, or paste with Ctrl+V. Photos with strong colour and good contrast take the effect best.

  2. 2

    Pick a direction and strength

    Slide in negative chemistry is the familiar cyan-shadow look. Watch the curve display while you drag; it is the real lookup table.

  3. 3

    Set the shadow lift and export

    Lift is what fills the shadows with colour and is the most recognisable part of the effect. Save individually or as one ZIP.

Three curves, and a foot that does not reach zero

Why it cannot be one curve

A colour cast multiplies every channel by a constant, and a contrast adjustment applies the same curve to all three. Cross processing does neither, because the three dye layers in the film react differently to chemistry meant for a different film. One channel gets a hard S-curve and gains enormous contrast, another gets a gentler one, and a third loses the toe of its curve so it can no longer render true black. Reproducing that means three separate lookup tables, which is what this builds, and it is why the curve display shows three lines rather than one. At the default settings the three diverge by up to 15 levels between red and green, 29 between green and blue and 44 between red and blue, which is what produces the colour separation rather than a cast. All three are constructed from monotonic pieces so no channel can ever invert: we check every setting the sliders allow, in both directions of the process, and no table decreases at any step in any channel.

The lifted foot is the signature

The detail people actually recognise is what happens at the dark end. When a channel's curve is lifted off zero, black stops being available in that channel, so the darkest area of the photograph is not black but whatever colour the lifted channel contributes. In the slide-in-negative direction that channel is blue, which is why the shadows of a cross processed photograph go cyan rather than dark. You can see it directly in the curve display: the blue line leaves the bottom left corner while the red one still touches it. We measure it too, feeding pure black through the curves at the default settings. It comes out as 2, 6, 29, a distinctly blue shadow floor rather than black, and with the lift at zero the same input comes back as 0, 0, 0.

What people use it for

Fashion photography

Cross processing was a fashion editorial staple through the nineties and keeps returning.

Album and single artwork

The extreme colour separation reads as deliberate art direction rather than as a photograph.

Music and gig posters

High contrast with coloured shadows survives being printed cheaply and viewed from a distance.

Film emulation

One of the few looks that genuinely cannot be reproduced with saturation and contrast alone.

Skate and street photography

The genre adopted the look early and it still carries that association.

Social media presets

Applying identical settings across a set is most of what a preset pack sells.

Faded and washed looks

Heavy shadow lift with soft curves gives a faded print feel rather than a punchy one.

Product and lifestyle shoots

A subtle setting adds a film character without announcing itself.

Six tips worth knowing

The shadow lift is the signature. Set it to zero and you have a contrasty photograph, not a cross processed one.

Watch the curve display rather than only the image. Where a line leaves the bottom left corner, that channel is filling your shadows.

Try the warm direction. Almost every cross process filter only does the cyan-shadow version, so the other one still looks fresh.

Photos with strong colour and good contrast take the effect best. A flat, muted photo has little for the curves to separate.

Fix white balance first. Cross processing on top of an existing cast produces something neither you nor the chemistry intended.

Keep JPEG quality above 90. The effect pushes contrast hard, which exaggerates any compression artefacts already in the file.

Troubleshooting

It just looks contrasty

Your shadow lift is too low. That control is what fills the darkest areas with colour, and it is the part people recognise as cross processing.

The colours look muddy

Strength and contrast are probably both very high on a photo that was already saturated. Lower one of them.

Shadows are grey rather than coloured

Check which direction you are using. Slide in negative chemistry lifts the blue channel and gives cyan shadows; the other direction lifts red and green instead.

Skin tones look wrong

They will, and that is the effect working. Cross processing distorts each channel differently, and skin is where it shows most. Lower the strength if you need people to look natural.

Frequently asked questions

What is cross processing?

Developing film in chemistry meant for a different type of film. Slide film in negative chemistry, or the reverse. It produces wildly distorted colour, extreme contrast and shadows that fill with a colour cast.

Why can it not be reproduced with saturation and contrast?

Because the distortion is not uniform. Each dye layer in the film reacts differently to the wrong developer, so the three channels end up with three genuinely different tone curves. A colour cast affects everything equally.

What is the shadow lift?

It raises the foot of a channel's curve so that channel can no longer render true black. The darkest parts of the photograph then fill with that channel's colour, which is the single most recognisable part of the look.

Can you show what that does?

Feeding pure black through the default curves gives 2, 6, 29, a blue shadow floor rather than black. With the lift at zero the same input comes back as 0, 0, 0 and the shadows stay properly black.

What is the difference between the two directions?

Slide in negative chemistry gives the familiar cyan shadows with a hard red curve. Negative in slide chemistry lifts red and green instead, producing warm shadows and a heavy blue curve. The second is much rarer in filters.

What is the graph under the sliders?

The actual red, green and blue lookup tables being applied, redrawn as you drag, with a dashed identity line behind them. It is the fastest way to see what the effect is doing.

Can a channel invert?

No. All three tables are built from monotonic pieces, and we check every setting the sliders allow: no table decreases at any step in any channel.

Why do skin tones look strange?

Because the effect distorts each channel differently and skin is where that shows most. It is the effect working rather than failing, but lower the strength if you need people to look natural.

It just looks contrasty to me

Raise the shadow lift. Without it you have three hard curves and black shadows, which reads as a punchy photograph rather than a cross processed one.

Should I use it before or after other edits?

After white balance and levels. Cross processing on top of an existing colour cast produces something neither you nor the chemistry intended.

Which photos suit it?

Strong colour and good contrast. A flat, muted photo gives the three curves little to separate, so the result is subdued rather than striking.

How is it different from split toning?

Split toning adds two chosen colours at the two ends of the tonal range without changing contrast. Cross processing changes the contrast of each channel independently, which is a much larger and less controllable distortion.

Is this how film labs actually did it?

Labs simply ran the film through the wrong process. This reproduces the resulting curves rather than simulating chemistry, which is the practical way to get the same look from a digital file.

Are my photos uploaded to a server?

No. The channel curves and the export both run in your browser using the canvas API. Nothing is sent anywhere.

Which format should I export?

Keep the original for photographs, at quality 90 or above. The effect pushes contrast hard, which exaggerates any compression artefacts already in the file.

Is transparency preserved?

Yes for PNG and WebP output. The alpha channel is untouched. JPG has no alpha, so transparent areas are filled with the background colour first.

Can I process a batch?

Yes. Add as many photos as you like and the same direction, strength, lift and contrast are applied to each.

Does it add a watermark or need an account?

No to both. No sign-up, no email wall, no daily limit and no watermark on the output.