The batch image processing form allows to process one or more images, creating a new
image instead of overwriting the original.
Action |
Description |
Uses Image |
|
|
Dark
(or
Bias) |
Merge
Flat |
Median
combines the Flat frame with one or more images. |
Flat |
Merge
Dark and Flat |
Subtracts
the Dark frame and then median combines the Flat frame with one or more images. |
Dark
& Flat |
Average |
Averages
the pixel values at each X/Y position in all the selected images to create a single value
placed in the new image. No registration is performed.
Good for
making master darks and/or flats. |
None |
Median |
Median
combines the pixel values at each X/Y position in all the selected images to create a
single value placed in the new image. No registration is performed.
Good for
making master darks and flats. |
None |
Median
Normalized |
Finds
average value of center region of first image to create a scaling factor. All images are
multiplied by this factor so that the centers of all the images have approximately the
same average. This accounts for fading/brightening sky when getting sky flats.
After
scaling is done, then median combine as described above is performed. No registration is
performed.
Good for
making master darks and flats. Particularly good when making sky flats that have stars. |
None |
Add
Operator |
Adds the
pixel value at X/Y in the operator image to the one at the same X/Y in each selected
image. No registration is performed. |
Operator |
Subtract
Operator |
Subtracts
the pixel value at X/Y in the operator image from the one at the same X/Y in each selected
image. No registration is performed. |
Operator |
Multiply
by Operator |
Multiplies
the pixel values at X/Y in the operator and selected image to create a new pixel value. No
registration is performed. |
Operator |
Divide
by Operator |
Divides
the pixel value at X/Y in the selected image by the value at the same X/Y in the operator
image. No registration is performed. |
Operator |
Merge
with Operator |
Adds the
pixel value at X/Y in the operator to that of the value in the selected image at the same
X/Y. The value for each can be scaled, giving more weight to one image or the other. In
video terms, a partially dissolved image is created. No registration is
performed. |
Operator |
Stack
(Average) |
The same
as Average except that all images are registered. Greatly increases SNR while cutting down
noise. The Operator image is the reference image.
Canopus
must be able to AutoMatch the images. |
Operator |
Stack
(Average, Multi) |
Stacks
multiple images using average value as one group or in groups of a certain number, e.g.,
you can stack 100 images in sets of three.
Canopus
must be able to AutoMatch the images. |
None |
Stack
(Sum) |
The same
as Add except that all images are registered. Greatly increases SNR. Noise reduction is
not as great and may actually increase. The Operator image is the reference image.
Canopus
must be able to AutoMatch the images. Result images are converted to 32-bit integer to
avoid reaching saturation. |
Operator |
Stack
(Sum, Multi) |
Stacks
multiple images using summed value as one group or in groups of a certain number, e.g.,
you can stack 100 images in sets of three.
Canopus
must be able to AutoMatch the images. Result images are converted to 32-bit integer to
avoid reaching saturation. |
None |
Noise
Reduction |
Reduces
noise in the image by performing a median comparison of pixels in a 3x3 region around each
pixel. If the pixel value varies from the median by more than a user-set amount, the
median value of the 9 pixels is assigned to the pixel being examined. |
None |
Fix
Column |
Same as
Noise Reduction except that the operation is limited to a single column. |
None |
Resample |
Resamples
one or more selected images to 8x, 4x, 2x, 1/2x, 1/4x, or 1/8x original size (uses
Factor setting). |
None |
Pixel
Math (Add) |
Adds a
fixed value to each pixel in one or more selected images. Over and underflow checking is
performed. |
None |
Pixel
Math (Subtract) |
Subtracts
a fixed value from each pixel in one or more selected images. Over and underflow checking
is performed. |
None |
Pixel
Math (Multiply) |
Multiplies
each pixel value in one or more selected images by a fixed amount. Over and underflow
checking is performed. |
None |
Pixel
Math (Divide) |
Divides
each pixel value in one or more selected images by a fixed amount. Over and underflow
checking is performed as well as divide by zero. |
None |
Convert
to 16-bit |
Converts
one or more 8/32-bit integer or 32/64-bit floating point images to 16-bit integer. This is
useful when working with other programs that cannot handle all of the FITS image formats. |
None |
Convert
to 32-bit
integer |
Converts
one or more images to 32-bit integer format. |
None |
Convert
to 32-bit
float |
Converts
one or more images to 32-bit floating point format. |
None |
Pad
FITS to 2880 |
Pads the
FITS header to a multiple of 2880 bytes filling with spaces (ASCII 32) and pads file to
multiple of 2880 bytes, filling data beyond the image with ASCII 0. |
None |
Flop
(left-right) |
Reverses
pixel positions left-right (rotate 180° about
Y-axis). |
None |
Flip
(top-bottom) |
Reversed
pixel positions top-bottom (rotate 180° about X-axis). |
None |
AutoMatch
(WCS) |
AutoMatches
one or more images and inserts WCS information into FITS header. |
None |
Crop |
Crops
images to reduce the number of rows and/or columns. |
None |