• Lighting Design

  What’s the difference between these Arri lights?

  Posted by Adam Fischer on October 7, 2006 at 11:37 pm

  As this post will show, I don’t know enough about lighting to make an informed decision on a new purchase! I’ve been looking at the various kits on B&H and ran into these two. Can someone explain what is different about the lights that would make the 4 light kit cheaper than the three light kit? I guess it has something to do with one being Fresnel 1000s and the other being Arrilite 1000s(according to the description), but I don’t know what the difference is.

  Thanks for any input!

  Three light kit:

  https://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=72154&is=REG&addedTroughType=categoryNavigation

  Four light kit:

  https://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=72150&is=REG&addedTroughType=categoryNavigation

  Walter Graff replied 19 years, 6 months ago 5 Members · 5 Replies
• 5 Replies

• 

  Dennis Size

  October 8, 2006 at 5:04 am

  You’re paying extra for the brilliance (play on words intended) of the great physicist Jean Augustin Fresnel (1788-1827).
  Countless lighthouses can’t be wrong.

  Just buy the Fresnel kit. You’ll be much happier.

  DS
• 

  Bob Cole

  October 8, 2006 at 2:16 pm

  Dennis, I’d love to hear more about what makes a fresnel look so much better photographically than an open face. I can see it, but I can’t describe it.

  — Bob C
• 

  John Sharaf

  October 8, 2006 at 3:46 pm

  Bob,

  A fresnel focuses the beam into a more specular source, so that amoung other things it casts a sharper shaddow. In addition it is easier to cut with the barndoors or flag so that the shaddow is a hard straight line. With an open face, the whole oraface of the light is the source so the shaddow has a variation along the line of the cut.

  Furthermore the fresnel has a cleaner and rounder pattern and a smoother adjustment from spot to flood. You can observe this by looking at the pattern of the light on a large white card and comparing it to the open face.

  Of course there are advantages to the open face, namely that it puts out more light for a comperable wattage, because in the fresnel the glass itself absords some light. For use in a chimera, or for a bounced source this makes the open face preferable.

  JS
• 

  Adam Fischer

  October 9, 2006 at 4:13 pm

  Thanks for all the great info guys!
• 

  Walter Graff

  October 15, 2006 at 12:50 pm

  “Of course there are advantages to the open face, namely that it puts out more light for a comperable wattage, because in the fresnel the glass itself absords some light. ”

  Minor addition to this statement. The glass on a fresnel does not “absorb” light. The reason a fresnel does not cast as much overall light as an open face has to do with the reflector. Look inside a fresnel and you will see a smaller more polished reflector. The reflector in this case is designed to reflect light forward towards the lens. On an openface fixture the reflector is much larger, creates much more specular light reflection and hence makes the fixture more efficient.

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