- #1
randa177
- 91
- 1
Does anyone have any idea how to get the photometry of SDSS data?
From http://cas.sdss.org/dr6/en/" .randa177 said:Does anyone have any idea how to get the photometry of SDSS data?
Do you have the ObjID of the objects?randa177 said:Actually I would like to find the spectra and photometry for a set of objects,
I can find the spectra here:
http://www.sdss.org/dr6/tutorials/colorconstraints.html
I am wondering if I can find the photometry in a similar way?
Photometry is the measurement of the brightness of an object in an image. In SDSS data analysis, it allows us to determine the brightness and color of celestial objects, which can provide valuable information about their characteristics and properties.
SDSS data is collected using a specialized telescope and camera, and is processed through a series of algorithms to correct for various factors such as atmospheric effects and instrument noise. These processes can impact the accuracy of photometry results, so it is important to understand how they work and how they may affect the data.
Aperture photometry measures the total amount of light within a fixed area around an object, while PSF (point spread function) photometry measures the amount of light within the shape of the object's point spread function. PSF photometry is more accurate for crowded fields, while aperture photometry may be more suitable for isolated objects.
Some common challenges in photometry analysis include background subtraction, object deblending, and dealing with variable atmospheric conditions. These can be addressed by using specialized software and techniques, such as fitting a model to the background and utilizing image stacking to improve signal-to-noise ratio.
Photometric data from SDSS can be used in a variety of scientific research, such as studying the properties and evolution of galaxies, searching for new astronomical objects, and analyzing the composition and dynamics of stellar systems. It can also be combined with data from other surveys and telescopes for more comprehensive analyses.