KevinE Posted October 21, 2007 Share Posted October 21, 2007 Dont forget that your new scanners have metal halide lamps in. They require running-in for a few hours before they reach full brightness if they're brand new. If they're ex-demo of course they'll either be already run in or possibly the lamps could be on their way out as they fade gradually with age. Link to comment Share on other sites More sharing options...
richardc1983 Posted October 21, 2007 Author Share Posted October 21, 2007 Ok well in total they have been on for about 5 hours so far and I wouldnt say they are any brighter than when I first turned them on!!! So I just dont know what the problem is, THe bulbs appear really bright inside the ficture almost blinding!!!! Red is the worst colour it just hardly shows!!!! Link to comment Share on other sites More sharing options...
norty303 Posted October 21, 2007 Share Posted October 21, 2007 Have you gone to the trouble of aligning the lamps in the reflectors on the discharge units? Normally done by 3 screws on the rear of the lamp mount. It can make a very significant difference. It should explain in the manual how to do it. I bought some second hand Robe fixtures where one lamp was out of alignment. It was about 50% as bright as the others and I thought the lamp was shot. A few turns of the screws did the trick. Link to comment Share on other sites More sharing options...
niclights Posted October 21, 2007 Share Posted October 21, 2007 I agree with above. "hot spot" alignment makes a huge difference (if available of course), and can easily account for 50% brightness. Also, are the bulbs themselves new? Although discharge lamps last far longer than halogen they do tend to cloud, brown and finally blacken toward the end of their life which also makes a huge difference. Check to see if the glass is clear or not. Regarding red, I would expect that to be quite poor, especially on a 150W lamp. This is one of the classic disadvantages of metal halide based light source, being of a higher colour temperature and thus having good low frequency (UV/Blue & apparent 'pure' white), but poor high frequency (ie. red). Tungsten based have the opposite characteristics. Finally, it is always worth cleaning any lenses/reflectors, especially if it appears used. It doesn't take long before a coating of dust/oil or nicotine can reduce output. Link to comment Share on other sites More sharing options...
richardc1983 Posted October 21, 2007 Author Share Posted October 21, 2007 yes I have done all the aligning of the bulbs etc. ANd they are setup correctly as mentioned above. It appears to me that a 150w discharge lamp will not be any brighter than a 250w ELC halogen lamp only a better colour temperature? Link to comment Share on other sites More sharing options...
Don Allen Posted October 22, 2007 Share Posted October 22, 2007 My experience with scanners is that 150 discharge are much brighter than 250 watt halogen. Have another go at adjusting the lamp in the reflector as that is where you are losing the intensity. Some manuals give a default distnce setting between the lamp base and the reflector. I note in this copy of the Geni Mojo Scan 3 manual http://www.optimalight.com/files/MojoScanIIX-IIIX.pdf on page 3 they mention "5.After installing the tube, tighten up screw A & C simultaneously, next tighten up screw B. Lock up the upper cover to get jobs done." I asume that screws A and C are the two outside screws holding the lampholder in place and screw B is the lampbase depth adjust screw. Try setting the lampbase to its fully out position so you will be adjusting it through its optimim "peak" position, as you may miss this peak if you start from past it and keep adjusting beyond it. Link to comment Share on other sites More sharing options...
richardc1983 Posted October 22, 2007 Author Share Posted October 22, 2007 Ok I have done that Its at its optimum settings. I have got it set to the best that it will go onto. Im thinking the only possible fault could be the bulbs. How do you know if the bulbs have reached end of life. These bulbs were supplied to me "as new" but I think maybe they are used Seems the only possible explanation for them not being very bright, especially on red and darker colours. The bulbs when I looked tonight one side of the bulb is yellow and although open white lokos quite bright it doesnt seem bright enough. How many hours do "new" bulbs need to be on (CSS150) to reach optimum brightness... kind of like a burn in time? Link to comment Share on other sites More sharing options...
david.elsbury Posted October 22, 2007 Share Posted October 22, 2007 Discharge *lamps* are (usually) always poor at red. This is how they are- the lamps are not faultyt and not neccesarialy used. Link to comment Share on other sites More sharing options...
niclights Posted October 22, 2007 Share Posted October 22, 2007 I've never been aware of any noticeable 'burn-in' time. New bulb should be clear, possibly with small white marking on one side. Used bulbs range from cloudy through to very brown. Link to comment Share on other sites More sharing options...
daemon Posted October 22, 2007 Share Posted October 22, 2007 Regarding red, I would expect that to be quite poor, especially on a 150W lamp. This is one of the classic disadvantages of metal halide based light source, being of a higher colour temperature and thus having good low frequency (UV/Blue & apparent 'pure' white), but poor high frequency (ie. red). Tungsten based have the opposite characteristics. You've got that backwards. Blue/UV is high frequency and red is low. Link to comment Share on other sites More sharing options...
KevinE Posted October 22, 2007 Share Posted October 22, 2007 The CSS150 do tend to wear out quite quickly, (based on nightclub experience), mobile use will generally be kinder to them. If you want to improve the performance you can fit the HTI150 instead, its electrically similar but has a better spectral performance. http://www.nordiskmusik.se/Global/Produkter-bilder/HTI%20150_stor.jpg Link to comment Share on other sites More sharing options...
niclights Posted October 22, 2007 Share Posted October 22, 2007 You've got that backwards. Blue/UV is high frequency and red is low. Doh. Was thinking of wavelength. Can I blame that on age? Link to comment Share on other sites More sharing options...
richardc1983 Posted October 23, 2007 Author Share Posted October 23, 2007 I am sending back one of the discharges tmrw as both lights are giving different shades of light, this is after replacing the bulbs and swapping about, one is always giving a different colour tone. Im going to keep one of the discharge versions though. Getting all halogen tmrw . Link to comment Share on other sites More sharing options...
Jamtastic3 Posted October 23, 2007 Share Posted October 23, 2007 Ok so how much heat is given off from each lamp?Although you can get discharge versions of halogen based lights, can you convert a halogen fixing into a discharge fixing? Link to comment Share on other sites More sharing options...
KevinE Posted October 23, 2007 Share Posted October 23, 2007 can you convert a halogen fixing into a discharge fixing? I suppose so but it wouldn't be worth it. You'd have to replace the mains transformer for a control transformer. You'd need to add a ballast and an ignitor. Then you'd have to change the lampholder and bracket and reflector and upgrade the wiring and thermal protection. Take that as a 'no' !! Link to comment Share on other sites More sharing options...
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