dabek Posted March 21, 2011 Share Posted March 21, 2011 Hello I hope someone out there may be able to help me on this. I perform a hand shadow routine (here is a link to give you and idea of what I mean http://www.youtube.com/watch?v=ybVW3rlv9IM ) and even though have peen performing it for over 5 years I have yet to find a light source that I am happy with. In the past I have used a birdie with a 1cm filter on it and at present am using a simple industrial floodlight with reflector taken out and a 1cm filter, it works but just isn't as bright at I would like and also leaves alot of spill. Basically I need compact, lightweight, bright light source that will enable me to cast crisp shadows onto a screen also it needs to be able to plug into mains power at the side of stage.I usually mount the lamp onto a mic stand with boom to enable me to adjust the height etc. Depending on the venue, the depth (and therefore size of my shadows) vary. In smaller venues I use a projection screen ( as in the video above) where as in larger ones I may use the Cyc. Many lamps give a double or blurred shadow and some of them just aren't powerful enough for bigger venues. I have noticed that the light from a multimedia projector is both bright and crisp, is there anyway I can replicate this? I hope some of you can help me with this difficult spec, as you can no doubt tell I am no technical expert so any help for tis layman would be gratefully received! ThanksPaul Dabek Link to comment Share on other sites More sharing options...
ladyjayne Posted March 21, 2011 Share Posted March 21, 2011 First thing I thought of was either a blondie or a redhead, but not knowing how much space there is between you and the fixture they'll probably kick out way to much heat. Even an Arri might still be to powerfull. An other option might be a profile spot and use the shutter blades so the light doesnt spill over the edges of your screen. Link to comment Share on other sites More sharing options...
grandMA_the_2nd Posted March 21, 2011 Share Posted March 21, 2011 I have worked with Pilobolus who are masters of this.. either use a lcd projector on white which has crisp even field or a fresnel with the lens taken out.... Link to comment Share on other sites More sharing options...
dabek Posted March 21, 2011 Author Share Posted March 21, 2011 Hi Thanks for your thoughts on this.I think a profile may be a little too big and bulky, I fly abroad alot with my work so size and weight are really important. Can anyone identify this lamp, I think it may be more to do with film or photography. Hans Davis 2 210.jpg Cheers Pilobolus are using more of a wash effect I think as they cast shadows from behind a cyc rather than in front like my act, I'm looking for more of a tight spot effect than a wash.Thanks Link to comment Share on other sites More sharing options...
adam2 Posted March 21, 2011 Share Posted March 21, 2011 To achieve the desired effect requires a light source that is not only bright but also compact.The addition of a lens or relector increases the light in the beam, but also increases the effective size of the light source and therefore reduces the sharpness of the shadows.The traditional light source would be a carbon arc, but these are not much used these days.An LCD projector on white would work, but is bulky and expensive. As it is stated that MR16s have been tried with partial success, I would look to develope on this. Common wattages for MR16s are 20, 35, and 50, but 75 watt lamps are available, these would cast better shadows as they are brighter but no bigger.Remember that MR16s are primarily intended as a low cost, fairly long lasting light source for retail and d0m3stic lighting. The light output can be substantialy increased by running the lamp on a higher voltage.I would try 13.8 volts on a 12 volt lamp. Remember to use thick cable between the transformer and the lamp. Link to comment Share on other sites More sharing options...
themadhippy Posted March 21, 2011 Share Posted March 21, 2011 Alot of shadow shows ive seen use a fresnel without the lens,bright and with barn doors controllable size and shape Link to comment Share on other sites More sharing options...
dabek Posted March 21, 2011 Author Share Posted March 21, 2011 Thanks Adam.... food for thought! Will start experimenting. Cheers Link to comment Share on other sites More sharing options...
Brian Posted March 21, 2011 Share Posted March 21, 2011 Common wattages for MR16s are 20, 35, and 50, but 75 watt lamps are available, these would cast better shadows as they are brighter but no bigger.Or even something like an ELC at 250W and cheap as chips 'cos they are used in lots of cheapo fixtures. Link to comment Share on other sites More sharing options...
grandMA_the_2nd Posted March 21, 2011 Share Posted March 21, 2011 Hi Thanks for your thoughts on this.I think a profile may be a little too big and bulky, I fly abroad alot with my work so size and weight are really important. Can anyone identify this lamp, I think it may be more to do with film or photography. Hans Davis 2 210.jpg Cheers Pilobolus are using more of a wash effect I think as they cast shadows from behind a cyc rather than in front like my act, I'm looking for more of a tight spot effect than a wash.Thanks Its irrelevant wether u are doing front or rear projection... if you want a crisp clear image then a small desktop LCD projector would be perfect or a fresnel with the lens removed... If its size that is important then you can find some fab palmtop LCD projectors now... Link to comment Share on other sites More sharing options...
Jivemaster Posted March 21, 2011 Share Posted March 21, 2011 The ELC is a nice idea but it needs under running or a good fan to cool it. The lamp from a Kodak carousel projector is a 24v 250w a bare capsule tight filament lamp which needs a fan and a housing and a 24VAC supply Link to comment Share on other sites More sharing options...
dbuckley Posted March 21, 2011 Share Posted March 21, 2011 Howzabout a slide projector? The beam from these is perfectly focussed and thus should be "sharp". Link to comment Share on other sites More sharing options...
adam2 Posted March 21, 2011 Share Posted March 21, 2011 The ELC is a nice idea but it needs under running or a good fan to cool it. The lamp from a Kodak carousel projector is a 24v 250w a bare capsule tight filament lamp which needs a fan and a housing and a 24VAC supply True, the need for a fan adds cost and complexity, but perhaps not that much. I would first try a 12 volt 75 watt narrow beam MR16, over run a bit at 13.8 volts. If that does not suffice, then consider a 24 volt 250 watt lamp with a cooling fan. Not certain what the beam angle of the 250 watt lamp is ? might be too wide to be ideal, these lamps are intended to be used with an external optical system, not for the direct illumination of articles, and may therefore have a very wide beam.Any unwanted light can of course be masked or blocked, but it represents wasted or lost light. Link to comment Share on other sites More sharing options...
ladyjayne Posted March 22, 2011 Share Posted March 22, 2011 The elc idea got me thinking and remembered Showtec do THESE. with 2 50W or 75W bulbs it might just work. But maybe there would be 2 shadows? Link to comment Share on other sites More sharing options...
timsabre Posted March 22, 2011 Share Posted March 22, 2011 The elc idea got me thinking and remembered Showtec do THESE. with 2 50W or 75W bulbs it might just work. But maybe there would be 2 shadows? 2 lamps bad!! You would get 2 shadows. As someone has already said, you need the smallest single source - a "point source". Having worked with ELC lamps and similar in dodgy disco products, it's not just a fan, you need to design a whole cooling system around the lamp, or the lamp life will be measured in minutes. Link to comment Share on other sites More sharing options...
sguy42 Posted March 22, 2011 Share Posted March 22, 2011 The traditional way to do this was a Linnebach projector, essentially a lamp in a box. Strand produced one in the '60s a Patt 223L but they are very rare. We have had some success in reproducing these by removing the lens and the reflector from Patt 223 / Patt 743 fresnels. There are a number of saftey issues with this (access to unprotected lamp & electrical termoninals etc), feel free to pm me if you want to go down this route. Shane Link to comment Share on other sites More sharing options...
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