To obtain phage morphometrics, use ImageJ online, or download to a PC. After you open your phage image, you’ll need to set the scale for measuring features.
- Analyze tab > Set Scale
- Distance in pixels = 1
- Unit of length = nm
- Input the appropriate pixel size into Known distance
- You can this value in the associated .txt meta data file.
- Or look for image magnification at the bottom left of the image (circled in red) and use corresponding pixel values listed here:
x50.0k Pixel Size=0.2380
x60.0k Pixel Size=0.1983
x80.0k Pixel Size=0.1488
Measuring features
- To measure capsid width, select the Straight Line tool. Click once to specify the beginning point of your line and then drag the mouse to the end point, and release.
- Choose Analyze tab and select Measure.
- The Results window will open and scroll to find the Length value.
- Use the Segmented Line tool to measure curved tails more accurately.
