I got mines in a dumpster, how ironic! Maybe Sylvania also uses the mercury dosing bottle, like Philips do with ALTOs.

Quote from: TiCoune66 on October 08, 2009, 07:55:00 AM

Well, I have found a pair of Sylvania F32T8/CW, one 741 the other 841. Both are ecologic and last December when I first tested them they acted like you said. Today they are prefectly fine. That "warm-up" mercury starvation generally disappears with use (I mean the more you run it, the less the problem is).

I also have a bunch of Sylvania F32T8/CW 741 ecologic lamps that start with the ends bright and the centre dim. They gradually warmup the full brightness. This warmup stage doesn't seem to go away in mine. I don't have a problem with the T12 low mercury lamps though.   

This behavior correspond to amalgam used as mercury reservoir - it need higher temperature to yield sufficient mercury vapor pressure (some amalgams yield way lower mercury partial pressure above them then pure mercury, that's why they allow higher temperature operation, but need a warm-up). As amalgams are on ends, required amount of mercury starts there and then it has to diffuse trough whole lamp length - so why it light gradually from ends.
It does not look for me as a lamp fault (like not opened capsule, and so on), neither signature of approaching mercury starved end-of-life, but normal consequence of used mercury pressure control concept. I would not see anything bad with this, when the few minutes warmup time is not a problem.

At walmart in evergreen, they have tons of ALTOS in the lights. here is a pic of one:

http://www.disasterous.org/alto.jpg

Yeah, the amalgam dosing bottle is definitely not made for fluorescents. We should think that, back in the late 30s, the fluorescents have not been invented without any mercury dosing system and not designed to have a such thing. They were also designed to be preheated, that's why preheat fluorescents are still today in late 2009 the most reliable fluorescent lighting systems. Even the GE Ultramax ballasts and ALTO II fluorescents won't beat any preheat F40CW mainlighter. 

I often see mercury starved Altos T8s everywhere now It's sad that many T12 systems are still going strong while many T8 systems have ballast failures and mercury starved lamps. Some of the one I've seen have been installed for less than 3 years, I even saw one that turned dim red and flickered all the time.

@Vince I agree with you completely about preheats Vince especially with choke ballasts I find that they have much less loss than the equivalent trigger start ballast and weight much less. They also start the lamp more reliably than trigger start.

I dont have very long and wide experience about alto lamps. To be precise I have only tested and used F20T12/CW lamps and have not yet had any problem with those. ofcourse because I live in Finland I have used them only with preheat fixture.

But in here and probably elsewhere in europe too philips is selling master TLD serie of fluorescent lamps. the coolwhite colors are generally okay but warmwhite 827 have worst cold starting quality I have seen yet. In my friend's dad's garage. there are 8 2X36W open(office style) fixtures. some of the lamps had gone out and the owner of garage 
went to a local supermarket(wich in a first place is a wrong place for finding good quality lamps in Finland) well there was only these philips master TLD lamps avaiable and only in color 827(this is pretty common case in finnish supermarkets).in supermarkets, these are usually wrapped in "deluxe" sleeve wich has a fine print on it and not kind of bulk sleeve like other lamps usually. he bought them. and even in summer you can see wich fixture has this kind of lamp when you start them and couple of minutes after that. but in winter. there is no automatic heating system in the garage. and there could sometimes be even -30 celcius. most of other lamps (mostly osram) will light up and will be acceotable brightness when you consider temperature. but for those philips lamps they usually remain pinkis(like mercury starved) for many minutes before gaining their true color. this probably has nothing to do with the ALTOs, these lamps were probably just not designed to be used anywhere cold.

@Roi: For such cold areas T12 are still made and sold by OSRAM...
And generally open fixtures are designed for normal, indoor operation, what mean temperatures not below 15degC...

@Roi: For such cold areas T12 are still made and sold by OSRAM...
And generally open fixtures are designed for normal, indoor operation, what mean temperatures not below 15degC...

Yeah, I know. There is also those thermo lamps. But I think money is the main question. T12 lamps like those thermo lamps are very expensive(even if compared to a good quality FL) in Finland and enclosed fixtures are more expensive than open. In here lapland where sales are small, shops dont usually have T12 lamps in storage article so you have to order them and that rises the price. They cost easely 10-20EURO per lamp and that is expensive. I found one company in south Finland wich sels cheap T12 lamps. These lamps are made by French manufacturer Claude. I ordered one box of those and have nothing bad to say about them. those seems to be okay. sadly they did have only coolwhite lamps.