BVRIJHK Photometry: What Do the Letters Stand For?

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The letters in BVRIHK photometry refer to specific wavebands in the Johnson photometric system, ordered by increasing wavelength, with the first four being optical and the last three infrared. Users are seeking clear explanations of the technique rather than just results, as existing online resources often lack detailed descriptions. The discussion highlights that the brightness measurements through different filters indicate relative reflectance, with the highest value typically set at 1.00. Clarification on the application of filters and their significance in measuring brightness is also sought. Overall, the thread emphasizes the need for better resources on the photometric process.
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What do the letters stand for? Blue, Violet, Red, Indego?

Does anyone have a link explaining the process? Google only seems to give articles describing results from using the technique without explaining what the technique is.
 
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tony873004 said:
What do the letters stand for? Blue, Violet, Red, Indego?

The quick and dirty answer is that those letters refer to specific wavebands in Johnson photometric systems. They run in order of increasing wavelength. The first four are optical wavebands and the last three are infrared ones. More information here:

http://www.starlink.rl.ac.uk/star/docs/sc6.htx/node10.html"


Does anyone have a link explaining the process? Google only seems to give articles describing results from using the technique without explaining what the technique is.

What process are you referring to exactly? The process of applying filters?
 
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Thanks, ST.

The quick and dirty answer and that link was all I needed :smile: . I was reading the journal on the discovery of 2003UB313. ( http://arxiv.org/abs/astro-ph/0508633 ) Based on the context I had a good idea what this was, but I had never heard of it and didn't know what bands the letters represented.

It states that the brightness is highest through the R and I filters, each with a relative reflectance of 1.00. Am I correct to assume that whatever filter gives the highest value will be considered to be 1.00?
 
tony873004 said:
Am I correct to assume that whatever filter gives the highest value will be considered to be 1.00?

That's what it looks like, though I've never seen the term explicitly defined. I think that table is just telling you how reflective the object is in the different bands (relatively speaking).
 
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