VJForums  

Go Back   VJForums > Technique > Hardware

Notices

Reply
 
Thread Tools Display Modes
  #1  
Old 20th February 2012, 12:13 PM
madsmeskalin's Avatar
madsmeskalin madsmeskalin is offline
Torkonfoslak
 
Join Date: Dec 2009
Location: Oslo
Posts: 667
Send a message via Skype™ to madsmeskalin
Default 2 x 6500 vs 15000 ansi lumen

Im doing a gig in an indoor location, and the promoter asked me what would be best. 2 x 6500 ansi lumen projectors, or 1 x 15000 ansi lumen projector. I was thinking maybe to go with two, as we need to cover at least a 12 wide screen. There will be a lot of lights. What do you guys think?
__________________
www.madsmeskalin.com
Reply With Quote
  #2  
Old 20th February 2012, 02:19 PM
many2's Avatar
many2 many2 is offline
Senior Member
 
Join Date: Apr 2002
Location: CANADA
Posts: 2,697
Default

It really depends...

What is the exact size of your screen ? If the ratio is around 4:3 and your width is 12 m, that gives you over 1000 sq feet of projection area. 15000 lumens will give you around 15 footlambert, which is OK for a very dark environment (similar to cinema film projectors). 2x6500 in convergence will give you less in that situation.

If your ratio is more like 8:3 (very widescreen), then you'll have better results with 2x6500 each covering half of the overall image.

The other thing to consider is backup : if you have 2 projectors, well it means that if one fails then you can still have a show. A dimmer show, but still a show. For some projects this is essential. If a show has 2000 paying audience members, and each pays 100$, then you can quickly establish that a missed show is already worth more than the price of a live backup unit. On some projects, video is more like an add-on and a video system failure would not force a cancellation - in those cases, a backup is not as essential.

Also consider other factors : projector positioning, lenses and other optics issues, shadows, power requirements, install complexity, transport - so many things to consider beside brightness.

Finally, there is one thing that is very important for me but that is often overlooked : black levels. No standard video projector can output black : the best they can do is dark grey. Let's say that this grey is worth "10" (this is just a value for the sake of example, it's not an actual measure). If you use two projectors in convergence, then you add those two dark greys together, and your darkest possible black now has a value of "20" - twice as bright as the one you'd get from a single projector.
Reply With Quote
  #3  
Old 20th February 2012, 02:20 PM
many2's Avatar
many2 many2 is offline
Senior Member
 
Join Date: Apr 2002
Location: CANADA
Posts: 2,697
Default

It really depends...

What is the exact size of your screen ? If the ratio is around 4:3 and your width is 12 m, that gives you over 1000 sq feet of projection area. 15000 lumens will give you around 15 footlambert, which is OK for a very dark environment (similar to cinema film projectors). 2x6500 in convergence will give you less in that situation.

If your ratio is more like 8:3 (very widescreen), then you'll have better results with 2x6500 each covering half of the overall image.

The other thing to consider is backup : if you have 2 projectors, well it means that if one fails then you can still have a show. A dimmer show, but still a show. For some projects this is essential. If a show has 2000 paying audience members, and each pays 100$, then you can quickly establish that a missed show is already worth more than the price of a live backup unit. On some projects, video is more like an add-on and a video system failure would not force a cancellation - in those cases, a backup is not as essential.

Also consider other factors : projector positioning, lenses and other optics issues, shadows, power requirements, install complexity, transport - so many things to consider beside brightness.

Finally, there is one thing that is very important for me but that is often overlooked : black levels. No standard video projector can output black : the best they can do is dark grey. Let's say that this grey is worth "10" (this is just a value for the sake of example, it's not an actual measure). If you use two projectors in convergence, then you add those two dark greys together, and your darkest possible black now has a value of "20" - twice as bright as the one you'd get from a single projector.
Reply With Quote
  #4  
Old 21st February 2012, 09:59 AM
madsmeskalin's Avatar
madsmeskalin madsmeskalin is offline
Torkonfoslak
 
Join Date: Dec 2009
Location: Oslo
Posts: 667
Send a message via Skype™ to madsmeskalin
Default

It will depend on the native aspect ratio of the projector, but probably (2 x 16:10, or 2 x 4x3) connected with a dual head.

If we use one 15000 ansi lumen instead we will have to put it further back in the venue to cover the same area as 2 x 6500 ansi lumens. So what do you think would give best effect?

The promoter is mostly worried about light output, as there will be quite a light show. However, he will will try to setup the lights as not to interfere with the projections.

Oh, I see you already answered that one. Thanks alot, Many2! It´s great to have a forum where I can ask so many stupid questions at once :-P
__________________
www.madsmeskalin.com
Reply With Quote
  #5  
Old 21st February 2012, 11:17 AM
deepvisual's Avatar
deepvisual deepvisual is offline
visually challenged
 
Join Date: Sep 2002
Location: UNITED KINGDOM
Posts: 6,711
Default

Quote:
Originally Posted by madsmeskalin View Post
It´s great to have a forum where I can ask so many stupid questions at once :-P
yeah, I'm waiting for you to ask which way you should part your hair
__________________
www.deepvisual.com

Life is around you and in you
Let the sunshine in...
Reply With Quote
  #6  
Old 23rd February 2012, 08:12 AM
psyOptik psyOptik is offline
Junior Member
 
Join Date: Apr 2003
Location: in da clöb
Posts: 23
Send a message via MSN to psyOptik
Default Light show

What's the geometry, and how do you place your beamers? Is there enough distance for one 15k projector, will it have wide angle (which steals light at the edges) or std. lens?

The promotor wants cool projection and "quite a lightshow". Good luck with that

--> deepvisual: I think there's a forum where Mr. Meskalin can ask about grooming of hair, so I beg you, - do not solicit even more stupid questions..
Reply With Quote
  #7  
Old 23rd February 2012, 07:41 PM
madsmeskalin's Avatar
madsmeskalin madsmeskalin is offline
Torkonfoslak
 
Join Date: Dec 2009
Location: Oslo
Posts: 667
Send a message via Skype™ to madsmeskalin
Default

If somebody feels Im asking irrelevant questions, feel free to tell me. Snide remarks is not telling someone.

We gonna place the beamers in the light rig roughly 5 meters above the dancefloor. Its not a wide angle lens, but that's basically what I know about it. The lights are a big part of the night, so the promoter was a little concerned tht 6500 ansi lumrns might not cut it. What do you guys think?
__________________
www.madsmeskalin.com
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 01:30 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2013, Jelsoft Enterprises Ltd.
Ad Management plugin by RedTyger