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XMM-Newton Science Analysis System

ommosaic (ommosaic-2.11) [xmmsas_20211130_0941-20.0.0]


This section documents the parameters recognized by this task (if any).

The following parameters are for use in the image-alignment algorithm- the default values have been set by trial and error- changing any of them may significantly increase the cpu time without improving anything.
ParameterMand Type Default Constraints
List of input image datasets to be mosaiced
Name of output mosaiced image dataset
Name of output correlation file dataset
binaxisnoreal 0 : 2
Image binning factor. 0 means take the largest binning factor of all the input images and compute the output image using this value. 1 means that the output image will be a high-resolution image, 2 a low-resoloution one.
mincorrnoreal -1 to +1
Minimum acceptable correlation successful image alignment If 0 then no alignment attempted. If < 0 then images stacked even if the correlation is less than abs(mincorr)
nsigmanoreal20.5 :
Image pixel used in cross-correlation if the pixel value is at least background + max(1.0, nsigma * sqrt(background) ), where background is the computed background level at the pixel
minfractionnoreal0.50.05 : 1
Minimum acceptable area overlap of 2 images before alignment is attempted
maxdxnoint51 : 50
Maximum x and y offsets (in image pixels) between 2 images refereence pixels to be used in cross-correlation
numintervalsnoint21 : 100
The number of intervals to split an x or y offset value into. Ie the total number of x or y offsets to be used to compute the initial correlation coefficients will be (2xdx+1)*numintervals and (2xdy+1)*numintervals,respectively.
dinoint105 to 100
The correlation image will be 2*di+1 pixels square.
minnumpixelsnoint100 20 :
The minimum number of image pixels that lie above the background than can be used in the cross-correlation.
ParameterMand Type Default Constraints

XMM-Newton SOC -- 2021-11-30