Moravian instruments, Inc., source: https://www.gxccd.com/art?id=564&lang=409, printed: 17.8.2019 12:53:12
|SIPS undergoes continued development and new features are regularly added with every minor version release. This release brought the full support for the new Cx CMOS-based astronomical cameras, but numerous other features and enhancements were also added — for instance SIPS now understands two new types of star catalogs.|
With the introduction of C1 series of planetary and autoguider cameras and C2 cooled cameras, support for these new models were gradually added into subsequent SIPS releases. C1 cameras were fully supported in v3.11 and this version 3.14 fully supports soon to be released C2 cooled CMOS cameras.
Introduction of CMOS cameras required adding of the possibility to set camera gain. So, the SIPS main camera control window had to be slightly redesigned to free-up some space for gain control. The NIR preflash is set only sparsely. So, the preflash controls were moved into new dialog box, opened by single button, which label also shows whether the preflash is enabled or disabled. If the preflash settings has to be changed, click on the button opens dialog box.
If the connected camera does not support NIR Preflash, the button remains disabled. On the other hand, cameras allowing to set gain cause enabling of the newly introduced Gain count box.
SIPS camera drivers and also Imager window offer gain setting in the camera-specific units. This allows the best possible gain control — gain is set by the steps allowed by hardware. The problem is every camera allows different number of gain steps. The Gain count box upper limit is always set to the maximum possible gain, allowed by actually connected camera. If the user is not aware of the maximum possible gain, it is possible just to enter some really big number and the Gain count box cuts it to the maximum allowed number.
SIPS supported USNO-A2.0 and UCAC4 catalogs for astrometric plate solving. Two more catalogs were added: UCAC5 and especially USBO-B1.0.
While USNO-A2.0 is always distributed with big-endian byte sequence in integer numbers, USNO-B1.0 is available in both big-endian and little-endian variants. As Intel and AMD x86 computers are little-endian machines and at the same time PCs equipped with x86 are used by absolute majority researchers and scientists, little-endian variant of USNO-B1.0 is more common and also SIPS expects little-endian variant.
The UCAC5 catalog contains even less stars than UCAC4 and only offers better coordinates precision, so, its usage for photometry applications is not much beneficial. On the other side, USNO-B1.0 contains uncomparatively more stars than both USNO-A2.0 or UCAC4/5.
Using of USNO-B1.0 leaves almost no star in the field of view without cross-identification, which is especially useful when stars should be published etc. But USNO-B1.0 contains only very little information about every star. For example only red and blue magnitudes are given and these magnitudes do not fit any standard photometric system. On the other side UCAC4 catalog contains many standard magnitudes.
So, it is much better to use UCAC4 providing the star of interest is contained in it. If the star is missing from UCAC4, it is useful to use USNO-B1.0 at last to have a valid cross-identification and rough estimates of standard magnitudes calculated from red and blue values. Which catalog is then better to use? SIPS offers solution of this problem by offering a possibility to define secondary catalog in addition to the primary one.
If the particular image (plate) cannot be matched with primary catalog, SIPS tries the secondary one. But this is only a rare possibility, matching works either in both catalogs or in neither of them. The main purpose of the secondary catalog ot offer cross-identification of stars missing from the primary catalog. When the image is matched with primary catalog, SIPS matches all unidentified stars with a secondary catalog.
SIPS is a freeware and can be downloaded from the Download section of this web site.
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