jorge_prat Posted June 1, 2003 Share Posted June 1, 2003 I just move up from a condenser enlarger to a nice second hand LPL 4572 enlarger (same as Saunders 4500 series). Well, the problem is that I'm geting crazy with the enlarging times: I can easily spend 12 minutes exposing an 11 x 14 print! and that's just for the basic exposure. That can't be normal. The lamp is ok (250w), and everything seams to work fine. What is the problem? I know my negatives are little dense for this kind of light, but not for 12 minutes exposure. Please help me! Thanks in advance Jorge Prat Link to comment Share on other sites More sharing options...
armin_seeholzer Posted June 1, 2003 Share Posted June 1, 2003 Hi Jorge On your LPL must be something totaly wrong or is it the lens? What f-stop you take for the enlarging part? I work most with f8 for thad size and get around 40-60 sec. Tell us more what f-stop you are using what paper etc. I get 3-6 minutes only on AZO but this is a paper for contacts and very slow! Link to comment Share on other sites More sharing options...
donald_miller1 Posted June 1, 2003 Share Posted June 1, 2003 The problems of excessively long exposures can only be related to a matter of lens F stop (as already addressed), reduced voltage to the enlarger (will cause corresponding reduction in light output), or excessive negative density (from either overexposing or overdeveloping or both). I would do the following: check peak density of the negative (should be on the order of 1.25 above b+f), check voltage to the enlarger (should be 115 volt + or - 5 volts). Link to comment Share on other sites More sharing options...
bob. Posted June 1, 2003 Share Posted June 1, 2003 Check mains voltage - is your local voltage the same as that given on the voltage regulator? You appear to be in Chile so it should be 220V (according to a quick Google at least). Is there the correct voltage to the lamp (probably 24V - it's usually written on the lamp base, but don't touch the lamp with fingers; you do not want grease on it - it will blow much sooner). Try a new lamp (it's worth having a spare or two anyway). Cheers, Link to comment Share on other sites More sharing options...
jeff_schraeder1 Posted June 1, 2003 Share Posted June 1, 2003 Develop an unexposed piece of film. Use it to make a test strip with your enlarger set up as you normally do. Find out the exposure time needed to produce a maximum density black. This is the point where you can no longer tell the difference between the stripes on the test strip. If that exposure is in the 10-60 second range your enlarger is probably OK and your negatives are too dense, if that exposure is in the 12 minute range your enlarger is the problem. Could be your f-stop selection or a problem with the light source or perhaps something like a filter in the light path. Link to comment Share on other sites More sharing options...
ann_m Posted June 1, 2003 Share Posted June 1, 2003 Jorge, Your LPL may be similar to mine and equipped with an Light Attenuator....this will diminish the light by approximately 2 F-stops.... This is on the dial in colour module only.... look on the right side of the housing between the magenta and cyan dials there is a smaller dial turn this counter clockwise and you get the benefit of the 'full light'. If this is the problem and the dial is put in the 'open' position it should reduce your exposure time by 2 stops....Hope this helps....Annie. Link to comment Share on other sites More sharing options...
jorge_prat Posted June 1, 2003 Author Share Posted June 1, 2003 Thank's for all your answers. I'm using f8 apertures, so it's not a too much stop down problem. I live Chile where we have 220 voltage. The enlarger is made for this voltage. When I bought the enlarger, it came without the lamp, so I cheeked Saunder's web site to figure out the lamp output. Accordingly I purchased a 250w/84v. Maybe this can be the problem. The lamp has 84v. Do I need a differente voltage lamp for my country? Link to comment Share on other sites More sharing options...
photodon Posted June 1, 2003 Share Posted June 1, 2003 Jorge If you are using an 84 volt bulb, it only puts out 250w at that voltage, so you are only putting 24volts to it, and therefore putting out much less wattage, It's like turning down a dimmer! Get the proper 24volt, 250watt bulb,and it will cure your problem. It will also be a colder color temp. so your multi grade filtration will work better. www.doncameron.com Link to comment Share on other sites More sharing options...
jim_landecker Posted June 2, 2003 Share Posted June 2, 2003 As others have suggested, it's probably the wrong lamp. I believe the 220 volt versions (as distributed by Jobo in Europe, and probably as manufactured by LPL in Japan) come with a power supply that has output for a 24V lamp, while the American versions come with a power supply made by the distributor Saunders, which has an 84V output. Check the power supply, as it should have the output voltage written on it somewhere. Jim Link to comment Share on other sites More sharing options...
bob. Posted June 2, 2003 Share Posted June 2, 2003 Yup - looking more and more like the lamp voltage... I live in Europe (well, the UK, which is at least physically, if not emotionally, in Europe ;-)) and my LPL 45xx has a 24V lamp (240v mains supply). Cheers, Link to comment Share on other sites More sharing options...
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