🧼 Western Blot Image Cleaner — Invert, Contrast, Background

Western blot cleanup — what, why, and how

Cleaning a blot image is about improving readability without changing the scientific meaning. The controls below target common presentation issues (uneven background, low contrast, inverted capture). Everything runs locally in your browser.

What each control does

• Auto inversion — Detects whether the source has dark bands on light or light bands on dark and flips if needed so signal stands out against a uniform background.
• Contrast — Spreads pixel intensities around mid-tones to separate bands from background. Use moderate values; extreme contrast can crush faint bands or blow out bright ones.
• Background threshold — Pushes pixels on the background side of a chosen brightness to pure black (dark background) or pure white (light background), reducing blotchy haze while keeping bands intact.
• Brightness — Shifts all pixels up/down together. Useful for small global nudges; rely on contrast/threshold for separation.

A quick, ethical workflow

1. Start from the original export (lossless PNG/TIFF if possible). Avoid repeatedly saving JPEGs (adds artifacts).
2. Auto-invert (the tool does this) and then set background just high enough to flatten empty regions without nibbling into bands.
3. Add a small contrast boost to clarify band edges. If weak bands disappear, you’ve gone too far.
4. Minimal brightness adjustment to bring the dynamic range into a comfortable viewing window.
5. Sanity check: zoom to 100% and scan each lane; make sure faint, real bands remain visible and there are no hard halos or clipped plateaus.

Good practices for figures

• Consistency: Apply the same adjustments across lanes/conditions from the same blot.
• Transparency: Note global operations (e.g., “global brightness/contrast, background threshold”). Avoid selective edits on specific bands.
• No content editing: Do not erase, move, duplicate, or splice bands. If lanes are cropped/reordered for layout, clearly delineate with divider lines and describe in the legend.
• Scale & labels: Include molecular weight markers, lane labels, and exposure details if required by your venue.
• Export well: Prefer PNG/TIFF at the journal’s DPI (often 300–600). Keep the image grayscale (8-bit) unless color information is meaningful.

Common issues & how to fix

• Hazy background: Raise the background threshold slowly until the inter-lane area becomes uniform; then back off slightly to protect faint bands.
• Bands look “posterized” (blocky): Reduce contrast; big jumps can collapse gradients and create halos.
• Faint bands vanish: Lower the threshold or contrast a notch; consider showing the original exposure in the supplement.
• Inverted look (white bands): Leave inverted if it increases legibility, but be consistent across panels and note it in the caption.

Limitations & integrity

This tool performs global presentation edits (invert/contrast/threshold). It is not for quantitative densitometry. For measurements, analyze the raw acquisition with proper software and document the pipeline.

Tip: keep a copy of the unedited original and record your slider values for reproducibility.

All processing is client-side via HTML Canvas — fast and private.

Good practices

This tool is intended for readability. Avoid manipulations that could misrepresent results and always follow your lab and journal figure guidelines.

FAQs

Is processing private and offline?

Yes. Everything runs in your browser; images aren’t uploaded.

Does this alter data or just presentation?

It provides presentation-oriented cleanup (inversion, contrast, threshold). Use responsibly and avoid changing scientific interpretation.

What formats are supported?

Common raster formats like PNG and JPG supported by your browser.

Will this make my figure publication-ready by itself?

It can improve clarity, but requirements vary. Check your target journal’s policies.