Halogen to be banned

Agree it was beautiful, wouldn't agree it was particularly expensive. I never used anything else and regret its passing.

You are probably right, even if they were initially designed here.

Cheers, T i m

You do realise there is a vast range of florry tubes available? ie, not just white and warm white? Of course, as with most things, decent tubes are more expensive than the ones which come with the fittings.

There are tri-phosphor tubes on the market that are suitable for photography etc where light quality is important.

Try photographing red blue and green gels with your favourite film. Then make up a slide, half the developed film, and half the original gels, and project it onto a screen. Then tell us how wonderful colour film is. ;-)

It was the same price as Kodachrome 64 and Kodachrome 200 in 35mm format from what I remember.

I am very aware of that, this sub-thread was about efficiency rather than colour after Bill's comment. My post about colour was intending to be a throw away comment when making the comparison.

The old tubes were marked Sylvania, hardly a no-name brand.

One thing I didn't mention is that LED tube replacements claim a 270 degree output as opposed to the original at close to 360, hence this could account for some increase in output when viewing the lamp directly.

I think you have said this before. I suspect they're expensive? Don't they also degrade over time?

My mind is wondering again.

Bill

The same tube maker often does all the varieties. Cooking white may give you the best lumens per watt, but that says nothing about the light quality. Of course perhaps most don't care.

You tend to get the same with LED GLS bulbs. They appear as bright as their claimed tungsten equivalent, but may well be different when reflected light off ceilings etc is taken into account.

Given they have a very long life, a drop in the ocean. BTW, I've found hard driven LEDs deteriorate too. Not sure if this applies to domestic ones.

I think maybe the belief that fluos have a green cast comes from the was film and sensors respond to their spectrum.

Bill

I thought it was the same price as Kodachrome 64.

Bill

I'm sure the eye response is very different to film emulsion response. I am aware the emission from a tri-phosphor tube is not flat:

Kodachrome 200? That must have been after I stopped using film and went over to digital. The fastest I can remember is Kodachrome 64 - and that was pretty slow for interior shots. What speed was Kodachrome Super 8 cine film? I think it might have been 16, to get the finest grain possible - hence the need for powerful photoflood lights indoors ;-)

I found that Kodachrome was good for fidelity of colours, but was rather contrasty: you lost a bit of highlight and shadow detail, and the shadows were ever so slightly greenish. Ektachrome was better for this and was of course a lot faster (160 [tungsten], 200 or 400), but it had a slightly colder colour balance. I once push-processed Ektachrome 160 to 640 ASA (underexpose by two stops, get the lab to overdevelop by two stops) for some photos I was taking of my sister taking part in a gymnastics contest indoors under stage lighting. The results were not pretty: very contrasty and over-saturated colours. Nowadays I could use a digital camera at 3200 ASA in any colour of "white" light ranging from tungsten bulbs (2400K) up to outdoor shade (about 10000K) and get equally good results. You have to look pretty hard to distinguish 100 ASA from 3200 ASA with my DSLR.

One thing I discovered when I came to scan my dad's slides and mine with a scanner that uses IR to detect dust and correct for it, is that this does not work with Kodachrome: there is something in the emulsion which attenuates IR to a variable extent depending on slide density, whereas I presume IR dust correction assumes that film of any visible density attenuates IR equally. This means that Kodachrome slides scanned with dust-removal turned on have a strange tonal quality and slight blurring which varies with brightness - yuk! That was certainly the case for my Minolta film scanner and AFAIK is the case with all scanners which use IR to detect dust. Ektachrome, AgfaChrome and OEM films (eg Boots' slide film), and all colour negative films, work fine with dust-removal turned on. However I never cracked the problem of how to get faithful-looking scans of colour negs: the colours always looked a bit "artificial" and OTT, rather like the illustration on colour "plates" in a book from the 1930s-50s.

It is certainly a lot more exaggerated on colour slide film (especially Kodachrome) than to the naked eye. Colour negative film is affected too, but most print labs correct for colour cast. I remember taking two photos on colour neg, one by fluorescent light and one by tungsten light, without any colour-correction filters. Apart from differences in the shadows and reflections off shiny objects, the two prints were pretty much indistinguishable, even though there was a big difference in the negatives.

I've not seen the green cast with fluorescent lights with a digital camera. Depending on what colour temperature preset you use, you get either an orange cast or a blue cast (or no discernable cast), but never a green one. So there's something about digital sensors which means they don't suffer from it to the same extent - or else if it present at the sensor, it is automatically corrected by the sensor-processing. That is true of "raw" DNG files, as well as JPG which may have some normalisations.

The barn ridge is around 20'. The florries are hung from chains attached to the purlins so 18' and progressively lower.

These are weatherproof fittings (because I had some) and a pig to work on from a ladder. Simplest taken down and replaced with a tested modified unit.

A professional might have something embarassing to say about the rewireable fuses in a 3 phase distribution board:-)

The colour pigments used in a Bayer filter are likely to be a better fit to the eye sensitivity than a photographic emulsion. There are still issues about sensitivity to near IR which is generally filtered separately - off plane, usually within the lens.

This is caused by residual silver in the slide, not removed by the development process. Kodachrome processing was a lot more complicated and temperature sensitive than other types of slide film.

So gable end height on a newbild then.

There is noting wrong with fuses.

I just upgraded it and you were right, it wasn't HF (so at least that makes more sense re the hum).

I took it down so I could see / access it better and it's just a std LF job but with an unusual (to me anyway) 'built in' electronic starter.

It's on it's side, under the built-in-bed and over the workbench so the tube is 'facing' the back of the bench but as the underside of the bed is white [1] and the LED tube supposed to illuminate 270 Deg, the actual light (level and coverage) seems to be about the same as the florry, maybe a touch brighter (it was a 'high output' one).

The good thing though, it seems to be as quiet as hoped (unlike one in the kitchen that was also stripped of it's guts).

Cheers, T i m

Also, which may be relevant here - eye responses differ, sometimes by quite a lot - between people.

#Paul