Mis Páginas

lunes, 20 de abril de 2009

¿Por qué salen ojos rojos en las fotos?

En algún momento, todos hemos visto este efecto. Cuando estamos tomando fotografías de noche, las personas salen con ojos color rojo intenso. Por qué sucede este efecto de "ojo rojo" en las fotografías, y cómo podemos evitar o minimizarlo?

Este efecto de ojo rojo sucede debido a lo siguiente: En un ambiente nocturno o cerrado, sin luz diurna, la luz ambiental

my cat, snowball, with a very bad case of rede...Image via Wikipedia

usualmente es poca. Esto causa que la pupila del ojo humano automáticamente se dilate, permitiendo dejar entrar más luz para poder ver mejor. Sin embargo, una cámara en estas condiciones deberá utilizar un flash intenso para poder tomar una fotografía. Entonces, en el momento en el que dispara el flash, la pupila está abierta casi por completo, acostumbrada a la poca luz ambiental, y la luz del flash se refleja en la retina del ojo. Es este reflejo lo que queda capturado en la imagen. Ahora, por qué el reflejo es rojo? La retina del ojo está llena de vasos sanguíneos, así que ese es el color rojo que vemos: el color de nuestra propia sangre.
Este efecto es mucho más marcado en personas con ojos azules o grises, ya que el iris de sus ojos tiene menos melamina, y permiten pasar más luz a la parte posterior del ojo. En la mayoría de animales también se puede observar este efecto, pero en los animales con buena visión nocturna, el ojo no sale color rojo, sino blanco, azul o verde, dependiendo de la especie. Esto se debe a que estos animales tienen una capa altamente reflectiva en la parte posterior del ojo, llamada tapetum lucidum, el cual les sirve para poder ver en poca luz. Entonces, al tomarles una foto, el reflejo no es de la retina sino de esta capa.

Ahora, cómo podemos hacer para minimizar este efecto en las fotografías? Varias cámaras traen mecanismos automáticos que minimizan el efecto, disparando un flash de "preparación" un segundo antes de tomar la foto real, para que la pupila esté más cerrada en ese momento. Un truco que puede utilizarse es aumentar la luz ambiental en el cuarto o área, ya que esto también causará que la pupila se cierre. Si su cámara es de tipo dSLR con un flash removible, puede apuntar el flash hacia el techo o a una pared, y rebotar la luz, o simplemente alejar el flash de la cámara. Cualquiera de estas opciones reducirá o eliminará el efecto del ojo rojo en la mayoría de situaciones.

Visto en: Explicame

Lea..

17 comentarios:

  1. I think that I know her. Seems like we attended the same class last year or we had to do my homework together . She seems so familiar to me.

    ResponderBorrar
  2. I am impressed by the information that you have on this blog Assignment Help Ireland. It shows how well you understand this subject. Apart, you use some effect or if you want to remove that you can use red eye remover.

    ResponderBorrar
  3. Hello,
    I am Sophia Miller
    thanks for sharing this post.

    provide you best Assignment help Australia anytime.

    ResponderBorrar
  4. Your information is very detailed and useful to me, thank you for sharing. I hope you will always be up to date. We also provide affordable MBA Assignment help in uk.

    ResponderBorrar
  5. Nice blog! I really like your writing...i keep visit your website to read such an useful information.
    assignment help

    ResponderBorrar
  6. It’s a very attractive article thank you for sharing. A Statement of Purpose (SOP) is an application document that basically tells the reader who you are, your professional interests, what has influenced your career as well as your professional goals. The SOP gives you a platform to talk directly to the admissions committee. In other words, a statement of purpose gives you an opportunity to convince the admission committee that you are the right candidate among many qualified applicants. Learn more from SOP Writing Services .

    ResponderBorrar
  7. My Assignment Help Now is the valuable source of getting experts’ help for academic papers. Connecting with the well-qualified professionals helps you to score top grades. Students who have no ideas about how to start their papers, they can search for our superior assignment help service to compose their documents.

    ResponderBorrar
  8. Thank you for sharing such an informative article looking forward for part 2. Cycling outdoor could have been easy and very much achievable during one’s youth but it certainly isn’t in the golden years. Beyond age 60 people tend to tone down to less strenuous exercises. Well, you do not have to switch to other exercises if you are still passionate about cycling. Take advantage of Recumbent Bikes for Seniors .

    ResponderBorrar
  9. Este comentario ha sido eliminado por el autor.

    ResponderBorrar
  10. Este comentario ha sido eliminado por el autor.

    ResponderBorrar
  11. I’ve enjoyed reading through your article. This is a great post. Before you know it, you’ve run out of all of the time. At that point, the project becomes some sort of an emergency. That’s when finding some DNP capstone project help starts feeling conceivable. This page presents a few tips to help you successfully manage the DNP project writing process. Read more on DNP Capstone Project Writing Help .

    ResponderBorrar
  12. Thank you so much for such a quality article. Students seeking Nursing assignment help from us can rest assured as we only deliver them with assignments made followed by intensive research-based paper. Our in-house Nursing assignment help writers never fall short to research across online, offline, and updated sources of information to support the claims made in the assignment. Now you can get Buy Nursing Assignments

    ResponderBorrar
  13. This article has brought to an end my long internet search thank you. You’re a fresh DNP candidate. At this time, it’s too early to start worrying about your DNP capstone project. Possibly, the idea of working with a quality DNP capstone project writing service hasn’t crossed your mind. You still have time, don’t you? But time keeps playing tricks on people. At the start, it may feel like you’ve got more than enough time. Time flies, though. Before you know it, you’ve run out of all of the time. Read more on DNP Project Help

    ResponderBorrar
  14. We provide the best capsim simulations assignment help. We will guide you through all capsim business rounds..

    ResponderBorrar
  15. Interesting read, I loved the content I bookmarked the website for regular read CMI Assignment Help is tailor made and pocket friendly to our client.

    ResponderBorrar

Deja su opinión sobre este post