SDSS DR16 Finding Chart Tool

Finding Chart (ra, dec, scale, height, width, opt, query)

returns a JPEG image centered on (ra,dec), of size (height x width) where the image is scaled to an arbitrary scale (scale). In SDSS the default scale is 0.396127 arcsec/pix. Various drawing options can be specified (opt). Use mark query to select objects of special interest. If you're new to the Finding Chart, please see the Visual Tools main page and Getting Started with Finding Chart.

ra	center point right ascension in J2000 decimal degrees, hh mm ss.s, or hh:mm:ss.s
dec	center point declination in J2000 decimal degrees, dd mm ss.s, or dd:mm:ss.s
scale	arcsec/pixel (the natural scale of SDSS is 0.396127)
height	image height in pixels, limited to [64..2048]
width	image width in pixels, limited to [64..2048]
opt	options string, a set of upper-case characters, like 'GPST'.

This option will draw a triangle on top of objects selected by a marking string.
Objects must be inside the field of view of the image to be displayed.
The format of the string can be from the following choices:


1. List of objects. A header with RA and DEC columns must be included.
   Columns must be separated by tabs, spaces, commas or semicolons.
   The list may contain as many columns as wished.

   ObjId	RA	DEC	RMag
   1237666338116206715	18.877321	-0.859906	21.57310
   1237666338116206712	18.876854	-0.860976	12.82945

   
   
2. SQL SELECT query. RA and DEC columns must be included.

   SELECT TOP 10 p.objID, p.ra, p.dec, p.r
   FROM fGetObjFromRectEq(<ra1>,<dec1>,<ra2>,<dec2>) n, PhotoPrimary p
   WHERE n.objID=p.objID
   
   

3. String following the pattern: ObjType Band (low_mag, high_mag)

   ObjType:	S | G | P
   	marks Stars, Galaxies or PhotoPrimary objects.
   Band:	U | G | R | I | Z | A
   	restricts marks to objects with Band BETWEEN low_mag AND high_mag Band 'A' will mark all objects within the specified magnitude range in any band (ORs composition).
   Examples:	S
   	S R (0.0, 23.5)
   	G A (20, 30)

The characters present will select the corresponding option
from the list below. Characters not in the list are ignored.

G	Grid	Draw a N-S E-W grid through the center
L	Label	Draw the name, scale, ra, and dec on image
P	PhotoObj	Draw a small cicle around each primary photoObj
S	SpecObj	Draw a small square around each specObj
O	Outline	Draw the outline of each photoObj
B	Bounding Box	Draw the bounding box of each photoObj
F	Fields	Draw the outline of each field
M	Masks	Draw the outline of each mask considered to be important
Q	Plates	Draw the outline of each plate
I	Invert	Invert the image (B on W)

This application is based on an underlying web service, ImgCutout.asmx which can be called in many different ways, using the SOAP protocol, or just using the standard HTTP GET and PUT interfaces. The formal description is contained in the WSDL, Web Service Description Language document.

The getjpeg service can be directly called from any web page through the HTTP GET protocol. In order to build a dynamic cutout into your own web page, insert the following example. Naturally, replace the parameter values with your own. <IMG SRC="http://test.preprod.skyserver.sdss.org/dr16/SkyServerWS/ImgCutout   /getjpeg?ra=179.689293428354&dec=-0.454379056007667&scale=0.79224   &width=400&height=400&opt=GST&query=SR(10,20)">