FITS image viewer

Zooming

To zoom the loaded FITS image, scroll vertically with command held down.

Pixel Scaling

Once a FITS file is opened, the FITS tab will appear.

The sliders here can be adjusted to scale the image pixels.

Gamma	Gamma value
Gain	The higher the gain the smaller the transition width around the center value; contrast
X-Bias	x-coordinate of the bias point
Y-Bias	y-coordinate of the bias point
Lower Cutoff	Cutoff value for which pixel’s below that will be scaled to the FITS’s minimum pixel value
Upper Cutoff	Cutoff value for which pixel’s above that will be scaled to the FITS’s maximum pixel value