Trying to remember the photography classes I took years ago, the most familiar term it comes to my mind is &#039;halo,&#039; which corresponds to the second meaning of halation in the Online Merriam-Webster Dictionary (<b><a href="http://www.merriam-webster.com/dictionary/halation)" rel="nofollow noopener" target="_blank">http://www.merriam-webster.com/dictionary/halation).</a></b> <br /><br />ha•la•tion n. <br />1. A blurring or spreading of light around bright areas on a photographic image.<br />2. A glow around a bright object on a television screen.<br /><br />In some cases, instead of &#039;halo,&#039; it is possible to use &#039;auréola,&#039; both terms relating to rounded light/ optical effects. The Portuguese definition of &#039;halo&#039; can be found at Priberam&#039;s Dicionário da Língua Portuguesa (<b><a href="http://www.priberam.pt/DLPO/default.aspx?pal=halo):" rel="nofollow noopener" target="_blank">http://www.priberam.pt/DLPO/default.aspx?pal=halo):</a></b><br /><br />halo <br />(latim halos, -o, do grego latim hálos, -o, eira, grão na eira, disco do Sol ou da Lua) <br />s. m.<br />1. Círculo luminoso que às vezes se nota em volta do Sol e de alguns planetas devido a certo estado da atmosfera.<br />2. Círculo que rodeia o mamilo.<br />3. Fig. Auréola.<br />4. Brilho<br />5. Prestígio, glória.<br /><br />I came across a few options to translate halation as a technical photography term:<br /><br />1) First, it is possible to keep the original term in English, although most of the occurrences I found of this use actually refer to &#039;anti-halation&#039; (backing or coating) and not to the word &#039;halation&#039; alone<br />2) The Dicionário Editora de Português-Inglês (Porto Editora, 2009) translates halation as &#039;halação,&#039; but gives no examples and no further explanation (<b><a href="http://www.infopedia.pt/portugues-ingles/hala%C3%A7%C3%A3o" rel="nofollow noopener" target="_blank">http://www.infopedia.pt/portugues-ingles/halação</a></b> )<br />3) Professor Enio Leite Alves, from Sao Paulo University (Usp), mentions &#039;halo,&#039; &#039;ofuscamento,&#039; and &#039;efeito de neblina luminosa&#039; on his &#039;Glossário Fotográfico&#039; (<b><a href="http://stoa.usp.br/escolafocus/weblog/49774.html)" rel="nofollow noopener" target="_blank">http://stoa.usp.br/escolafocus/weblog/49774.html)</a></b><br />4) Finally, the most common Portuguese terms used in reference to halation seem to be &#039;halo&#039; (again) and &#039;efeito de halo.&#039; The latter is also used in psychological studies, I believe, as well as in graphic arts (referring to the printing process) but it appears quite frequently in photography.