Nez242 Posted April 24, 2012 Share Posted April 24, 2012 I'm sure I've seen a thread about this before but can't find it so here goes.... I acquired a Strand Harmony 12 some time ago. It has a T11 lamp. When focussing I get a beautifully sharp inverted image of the lamp which renders the whole thing useless. I enquired of our local hire company and they suggested that a fixed condenser lens maybe missing, but admitted that they didn't have a Harmony to check and had never taken one apart. I can't find a diagram on the interweb to check this theory out. Having dissected the lantern I cannot see where the fixed lens would be. Another theory is that it is the incorrect lamp. The original was listed as an RSE/19 or RSE/70 both of which are presumably discontinued or called something else. Any other theories, advice, suggestions, etc gratefully received. Link to comment Share on other sites More sharing options...
Junior8 Posted April 24, 2012 Share Posted April 24, 2012 There is a section on the Harmony range in the Strand Archive where I found this - there are no instructions for the 12 though. If the base is a GX9.5 then the T11 would be the right lamp I would think. (Edit - I'ver just checked and it is.) It is years since I handled a Harmony so I can't recall whether it had a fine adjustment screw under the lamp base. Link to comment Share on other sites More sharing options...
gyro_gearloose Posted April 24, 2012 Share Posted April 24, 2012 The lenses may be facing the wrong way. This is quite likely if the unit has been apart to be cleaned at some point in its life. Which way round are the lenses? Is the curved surface facing towards or away from the lamp? Do you have another unit you could compare it to? If not there are a couple of Harmonies on ebay right now, although there's only a Harmony 22 and a Harmony 15/28. Link to comment Share on other sites More sharing options...
Nez242 Posted April 24, 2012 Author Share Posted April 24, 2012 Thanks for suggestions so far. I have tried turning the lens around as that was my first thought. Strangely it made absolutely no difference. Link to comment Share on other sites More sharing options...
Junior8 Posted April 24, 2012 Share Posted April 24, 2012 Just a thought but what range, length of throw as we used to call it, are you testing it at? Link to comment Share on other sites More sharing options...
Nez242 Posted April 25, 2012 Author Share Posted April 25, 2012 Just a thought but what range, length of throw as we used to call it, are you testing it at? I've tried it anywhere between 1 and 10 metres. Link to comment Share on other sites More sharing options...
Stu Posted April 25, 2012 Share Posted April 25, 2012 I would try and google to see if there is another venue somewhere that has some Harmony 12's in stock, they are rare but not that rare that someone in the UK won't have some. They might be able to tip you off about lens orientation etc. I have to admit it doesn't strike me as the sort of lantern that would have had a condenser lens (but could be wrong!) so maybe the lens/es it does have are the wrong ones. Good luck! Link to comment Share on other sites More sharing options...
Brian Posted April 25, 2012 Share Posted April 25, 2012 ...RSE/19...Which is a T19 (RSE = Rank Strand Electrics). Link to comment Share on other sites More sharing options...
Supertrouper6 Posted April 25, 2012 Share Posted April 25, 2012 I would try and google to see if there is another venue somewhere that has some Harmony 12's in stock, they are rare but not that rare that someone in the UK won't have some. They might be able to tip you off about lens orientation etc. I have to admit it doesn't strike me as the sort of lantern that would have had a condenser lens (but could be wrong!) so maybe the lens/es it does have are the wrong ones. Good luck! If the lens is focusing on the lamp rather than the gate then I think that its focal length is too long indicating that either you have the wrong lens or possibly there should be two lenses in the lantern after the gate. Regretably I dont know what lens should be in a Harmony 12. Genearally a fatter lens will have a shorter focal length tan a thinner one of the same diameter. Hope this helps a bit Link to comment Share on other sites More sharing options...
Brian Posted April 25, 2012 Share Posted April 25, 2012 When I first read this I thought "there must be a lens missing" but now I'm not so sure. Looking through the Cadenza 8 info on the Strand Archive it makes specific reference in a couple of places to just one lens and I now have no reason to believe the Harmony 12 would be any difference. Which as the post above suggests means either a) it's the wrong lens or b) somehow it's in the wrong place. When the sun emerges it's easy to find out what the focal length is. Link to comment Share on other sites More sharing options...
rich_lambe Posted April 25, 2012 Share Posted April 25, 2012 Have the parts list here, Harmony 12 definitely has one lens only. Link to comment Share on other sites More sharing options...
Brian Posted April 25, 2012 Share Posted April 25, 2012 Have the parts list here, Harmony 12 definitely has one lens only. Interesting and very helpful. Sounds like the OP needs to remove the lens from its mount and move it backwards and forwards to see what the effect is on the field. Link to comment Share on other sites More sharing options...
vinntec Posted April 25, 2012 Share Posted April 25, 2012 I would try and google to see if there is another venue somewhere that has some Harmony 12's in stock, they are rare but not that rare that someone in the UK won't have some. They might be able to tip you off about lens orientation etc. I have to admit it doesn't strike me as the sort of lantern that would have had a condenser lens (but could be wrong!) so maybe the lens/es it does have are the wrong ones. Good luck!A quick Google reveals that the Medina Theatre http://www.medinatheatre.co.uk/techinfo.shtml have a pair on their technical info list? Peter Link to comment Share on other sites More sharing options...
AndyJones Posted April 25, 2012 Share Posted April 25, 2012 Blue Room member Medina is on the forum... Link to comment Share on other sites More sharing options...
kaareolai Posted April 26, 2012 Share Posted April 26, 2012 Thanks for suggestions so far. I have tried turning the lens around as that was my first thought. Strangely it made absolutely no difference. Maybe I just mention obvious tried things, but...Is Harmony 12 like an ordinary lamp with parabolic mirror reflector behind the lamp-bulb? Is it still with good reflection surface? Have you tried to adjust the lamp-bulb probably closer or (less likely) longer away from the reflector? There should be a knob or a screw to do such adjustments/fine-tuning of lamp position. Regards Kåre Link to comment Share on other sites More sharing options...
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