Puppeteer captures fuzzy visualization chart while other page elements remain clear

Other Questions Puppeteer
1

I’m using Puppeteer to take screenshots of a data visualization webpage, but I’m experiencing an odd problem. The main chart element appears blurry in my screenshots, while everything else on the page looks crystal clear.

Here is a sample of my code:

const puppeteer = require('puppeteer');
const fs = require('fs');

async function captureChart() {
    const browser = await puppeteer.launch({ headless: true });
    const tab = await browser.newPage();
    
    // High resolution settings
    await tab.setViewport({ 
        width: 1600, 
        height: 900, 
        deviceScaleFactor: 2 
    });
    
    await tab.goto('https://example-chart-site.com/chart', { 
        waitUntil: 'domcontentloaded' 
    });
    
    // Wait for chart to load
    await tab.waitForTimeout(3000);
    
    const imagePath = './chart-capture.png';
    await tab.screenshot({
        path: imagePath,
        type: 'png',
        fullPage: false
    });
    
    await browser.close();
    console.log('Screenshot saved!');
}

captureChart();

The strange thing is that text, buttons, and other UI elements are clear, but the chart visualization looks low resolution. I’ve increased the device scale factor, yet it doesn’t seem to resolve the issue.

I’m curious if this might be tied to how the chart is rendered, perhaps within a canvas or iframe, or if there are specific configurations I need for capturing dynamic visualizations. Has anyone else faced similar issues when taking screenshots of charts or animations using Puppeteer?

2

Had this exact same problem with D3.js charts last year. The blur happens because Puppeteer captures while the chart’s still animating or before GPU rendering finishes. Here’s what fixed it for me: Set your viewport first with await page.setViewport({ width: 1600, height: 900, deviceScaleFactor: 2 }) before navigating. Then disable hardware acceleration by adding args: ['--disable-web-security', '--disable-features=VizDisplayCompositor'] to your launch options. Also switch to networkidle2 instead of domcontentloaded for your wait condition - charts usually load data async after the DOM’s ready.

3

canvas elemnts can be a pain with puppeteer, huh? throw in await page.waitForSelector('canvas') and extend your wait time a bit. if your charting library has render events, wait for those to trigger too. it might help!