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FreeSat.
On 09/06/2021 18:05, T i m wrote:
The shame is (often old) people paying to have their new DTV 'set up' when in many cases you just plug it in and follow the onscreen prompts and it does it all for you (unlike the old ATV where you had to manually tune each button and the video etc). ;-) Or they try to install it themselves, it mis-tunes to the wrong tx, so they assume they need a 'digital aerial' and some **** in my trade comes along, rips them for £150, then tunes the TV correctly. Bill |
Halogen to be banned
On 09/06/2021 18:41, Fredxx wrote:
On 09/06/2021 17:23, williamwright wrote: On 09/06/2021 13:15, Andrew wrote: And fluorescent tubes are reasonably efficient in terms of light output vs power in. They are the same as LEDS Generally they're twice as efficient as fluorescent tubes. As this link demonstrates: Â* https://en.wikipedia.org/wiki/Luminous_efficacy Generally? Only one type. I know that when I've swapped fluos for LEDs the latter haven't seemed much brighter, if at all. Bill |
Halogen to be banned
"T i m" wrote in message ... On Wed, 9 Jun 2021 16:07:42 +0100, "tim..." wrote: snip I put the CFL back in 5W LED is just too damned bright to be turning on whilst you are sleepy The fact that CFL often take a few seconds yo 'warm up' helps with that. makes of LED bulbs really ought to think about this Some of the LED lamps that come on and off automatically as driven from my Home Assistant system seem to 'ramp the on brightness' slightly (quickly) and much more visually down when turning off Its trivially programmable to any rate you like with the Philips Hue system. (compared when turning them off at the wall) so that change in functionality is probably because they are being used 'smart'? When they are off at the wall they are completely off (electrically) of course whereas when off from Home Assistant they are still powered but are set to zero light output. If you set them to come on via a remote of some sort you can gave them come on at whatever level is appropriate (and that could vary depending on the time of day) but still be turned up or down as required (same remote). And by light level too. |
Halogen to be banned
On 09/06/2021 22:51, T i m wrote:
On Wed, 9 Jun 2021 15:24:17 +0100, Mark Carver wrote: snip I doubt LEDs will work in our John Lewis 'touch sensitive/three level' bedside lamps. FWIW I put a dimmable LED lamp in mums 'touch sensitive three level' table lamp (and two similar used as bedside lights) and it/they worked fine? I can't imagine it was bought with LED compatibility in mind but it could have been LED compatible of course. Interesting. I'll get an LED replacement bulb, and give it a spin then. They might have been bought from Homebase FWIW. I'm sure the 'guts' all come from the same place in China ! |
Lonely Auto-contradicting Psychotic Senile Ozzie Troll Alert!
On Thu, 10 Jun 2021 14:16:56 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again: Its trivially programmable to any rate you like with the Philips Hue system. Shove your idiotic Philips Hue up your senile arse, senile asshole! tsk |
FreeSat.
On Thu, 10 Jun 2021 02:05:05 +0100, williamwright
wrote: On 09/06/2021 18:05, T i m wrote: The shame is (often old) people paying to have their new DTV 'set up' when in many cases you just plug it in and follow the onscreen prompts and it does it all for you (unlike the old ATV where you had to manually tune each button and the video etc). ;-) Or they try to install it themselves, it mis-tunes to the wrong tx, (How often / easy is that to happen and under what circumstances would you say? I mean, don't the TV's often ask for your location / 'Region to (presumably) know what range of frequencies it should be looking for?) so they assume they need a 'digital aerial' ;-) and some **** in my trade comes along, rips them for £150, then tunes the TV correctly. ;-( If 'automatic' tuning doesn't work because it can be confused by which transmitter(s?) to use, would that mean tuning it manually and what typically happens after when a re-tune is required? Asking because we live in an area that is only really served by one TX so never had to manually tune a DTV. Cheers, T i m |
Troll-feeding Senile IDIOT Alert!
On Thu, 10 Jun 2021 00:29:18 +0100, D i m, the absolutely brain dead
notorious troll-feeding senile asshole, blathered, yet again: Cheers, D i m You'll thankfully keep feeding ANY filthy, vicious troll that comes along, eh, senile D i m? Just how miserable are all you senile assholes that are slowly taking over Usenet? G |
FreeSat.
"T i m" wrote in message
... (How often / easy is that to happen and under what circumstances would you say? I mean, don't the TV's often ask for your location / 'Region to (presumably) know what range of frequencies it should be looking for?) If 'automatic' tuning doesn't work because it can be confused by which transmitter(s?) to use, would that mean tuning it manually and what typically happens after when a re-tune is required? I imagine it depends on TV firmware as to whether the TV asks for a postcode to tune to the muxes on transmitter that is designated for that postcode, or whether it just does a scan from UHF 21 to UHF 68 to see what it can find. Usually you end up with all the muxes from the *same* transmitter, but I have seen cases when you get a mixtu before the aerial at my parents' holiday cottage was upgraded (presumably from grouped to wideband), there were problems that an auto scan would pick up some muxes from Bilsdale (the "correct" transmitter for that locality) and some muxes from Emley Moor (which is miles away over several hills). Until we had the aerial changed and a kink in the cable that fed the aerial wall-box repaired, I had to manually tune each mux to prevent it finding Emley. I presume, because of the old aerial's selective gain in different parts of the UHF spectrum, some Emley muxes were actually stronger than some Bilsdale ones. There is also the issue of atmospheric "lift" causing distant signals to be stronger at certain times, which is a problem if you retune at that time. |
FreeSat.
In article ,
williamwright wrote: On 09/06/2021 16:36, Dave Plowman (News) wrote: I sort of assumed with a 1 metre dish it would be pretty tolerant. Find any one of the Astra group and the others would be OK. But not so - obviously. If you look at the full spectrum at 28E on an analyser and gently pull at the rim of the dish you can see some signals strengthen whilst others weaken. Bill Right. I'd guess a spectrum analyser would be a bit of a luxury for me, though. ;-) I did quite a bit of Googling on setting up a motorised dish. Most of the Utube stuff just confused me, as I simply wanted an idiots guide. So here's mine:- Make sure the mounting pole is truly vertical. That could be tricky working off a ladder. Set the motor to 0. Mount the disc making sure it is pointing straight ahead, relative to that 0. Some dishes may not have a big enough flat on the back to use a set square, so measure from each side of the dish to the motor centre. Make sure the dish mounting is the correct distance up the motor mounting tube. Set the elevation on the motor adjustment, using the motor maker's data. And then the disc bracket angle. Now rotate the motor mounting to point due south. I found a phone app better than a compass. My receiver then found all the satellites in its list - with the exception of a couple to the west where my dish is looking through a thick large chestnut tree. -- *Don't squat with your spurs on * Dave Plowman London SW To e-mail, change noise into sound. |
FreeSat.
In article ,
NY wrote: I imagine it depends on TV firmware as to whether the TV asks for a postcode to tune to the muxes on transmitter that is designated for that postcode, or whether it just does a scan from UHF 21 to UHF 68 to see what it can find. Pretty well every TV I've seen in the last many years asks for your country and town, etc, before tuning. Of course if you live in a remote area, you may have a choice of transmitters. and may want to choose the one which gives you all the progs you want. -- *You can't teach an old mouse new clicks * Dave Plowman London SW To e-mail, change noise into sound. |
Halogen to be banned
In article ,
Fredxx wrote: On 10/06/2021 00:18, Dave Plowman (News) wrote: In article , Fredxx wrote: When I looked into this, the issue was with cars and not bikes. You can fit LEDs to cars if there is some self-levelling of headlamp aim and headlamp wash-wipes. Those rules don't apply to bikes. I also read that these rules only apply to lamps above a certain light output. That could make more sense. But I think you're wrong. That is the problem with headlight regs. They don't mention light output. I tried looking up the claim and have come to the conclusion I must have dreamt it. From: https://www.autobulbsdirect.co.uk/bl...gal-in-the-uk/ Please note that since January 2021, the MOT Inspection manual has been updated to include LED bulbs. Section 4.1.4 now states the following: ”Existing halogen headlamp units should not be converted to be used with high intensity discharge (HID) or light emitting diode (LED) bulbs. If such a conversion has been done, you must fail the headlamp.• This is a brand new update that seems to only focus on headlights. Yes, and it's typical broad nonsense. It depends on the design of your headlamp unit if a different light source gives a decently controlled beam. I did some tests on mine, which has projector headlights (the type with a bulls eye in front of the bulb) Have a convenient car park with a white wall, so you can see the beam pattern easily. It was identical with the original halogen, HID, and LED. This type of headlight gives a very sharp cutoff due to using a french flag to shape it. (It also allows an easy change from RHD to LHD by simply changing the flag - some do this with a lever) Non projector units will likely produce a lot of scatter when you change the light source, as the size and position of this varies with type of bulb, so will be out of focus. There are no mentions to fail other LED bulbs such as brake lights, tail lights or reversing lights." But there will still be idiots who change their colour. ;-) -- *When a clock is hungry it goes back four seconds* Dave Plowman London SW To e-mail, change noise into sound. |
Halogen to be banned
On 10/06/2021 02:14, williamwright wrote:
On 09/06/2021 18:41, Fredxx wrote: On 09/06/2021 17:23, williamwright wrote: On 09/06/2021 13:15, Andrew wrote: And fluorescent tubes are reasonably efficient in terms of light output vs power in. They are the same as LEDS Generally they're twice as efficient as fluorescent tubes. As this link demonstrates: Â*Â* https://en.wikipedia.org/wiki/Luminous_efficacy Generally? Only one type. I know that when I've swapped fluos for LEDs the latter haven't seemed much brighter, if at all. I would have thought the wiki article be a general comparison, BICBW. I have a direct comparison between some ageing fluorescent tubes and their LED counterparts. I recently replaced some Sylvania 6ft T5 tubes rated at 70W. I bought some Energiser replacements and these are cool white rated at 30W. Because of access issues I still have the original florries in some places. It means I can make side by side comparison. The LED tubes provide a natural white, where the florries have a magenta tinge, lacking green in comparison. Others have also commented that the LED tubes are brighter. You also have to take the ballast into consideration but given the temperature this runs at I guess the loss is 5-10W, possibly more. I shorted the ballasts when fitting the LED tubes. This is a place where there are 19 tubes, so the power saving is significant. After a year none has failed. These are branded tubes as I was wary about getting no-name ones. That is my experience, I fully accept YMMV. |
Halogen to be banned
"Fredxx" wrote in message
... It means I can make side by side comparison. The LED tubes provide a natural white, where the florries have a magenta tinge, lacking green in comparison. Others have also commented that the LED tubes are brighter. Interesting. To my eye, "daylight" CFLs have a very faint greenish tint, like looking through thick glass. And florrie tubes always used to reproduce on daylight slide film with a strong green cast: you used to be able to buy a pale magenta filter to compensate for it (*). So it is interesting that your florries look to have too *little* rather than too *much* green. Shows how unreliable film and the eyes are when faced with a discontinuous spectrum! (*) I wonder if the same filter worked for all films or whether some brands had different spectral sensitivities to others. And of course you'd need a different filter for each type (warm/cool-white) of tube. |
Halogen to be banned
On 10/06/2021 13:15, NY wrote:
"Fredxx" wrote in message ... It means I can make side by side comparison. The LED tubes provide a natural white, where the florries have a magenta tinge, lacking green in comparison. Others have also commented that the LED tubes are brighter. Interesting. To my eye, "daylight" CFLs have a very faint greenish tint, like looking through thick glass. And florrie tubes always used to reproduce on daylight slide film with a strong green cast: you used to be able to buy a pale magenta filter to compensate for it (*). So it is interesting that your florries look to have too *little* rather than too *much* green. Shows how unreliable film and the eyes are when faced with a discontinuous spectrum! Its fredxx he cant rell his arse from his elbow. It is well known that fluoros have an overall green cast. (*) I wonder if the same filter worked for all films or whether some brands had different spectral sensitivities to others. And of course you'd need a different filter for each type (warm/cool-white) of tube. It worked for all films more or less. No two film types were the same. Konica print was the film of choice for portrait as it rendered flesh tones brilliantly. Fuji did nice greens. As did Agfa. Kodak was horrible - glaring bright colors - ok for arty shots, but nowhere near natural Kodachrome however, especially 25, was a beautiful - and extremely expensive - film Age also makes a difference. I took two bodies on holiday to the Med once, and found one had film in it from ten years before. I shot it, but it came with a massive green cast. Digitised the negs and played around with Gimp and got very acceptable final results I think that was the last time I used a film camera -- "And if the blind lead the blind, both shall fall into the ditch". Gospel of St. Mathew 15:14 |
Halogen to be banned
On 10/06/2021 13:27, The Natural Philosopher wrote:
On 10/06/2021 13:15, NY wrote: "Fredxx" wrote in message ... It means I can make side by side comparison. The LED tubes provide a natural white, where the florries have a magenta tinge, lacking green in comparison. Others have also commented that the LED tubes are brighter. Interesting. To my eye, "daylight" CFLs have a very faint greenish tint, like looking through thick glass. And florrie tubes always used to reproduce on daylight slide film with a strong green cast: you used to be able to buy a pale magenta filter to compensate for it (*). So it is interesting that your florries look to have too *little* rather than too *much* green. Shows how unreliable film and the eyes are when faced with a discontinuous spectrum! Its fredxx he cant rell his arse from his elbow. Stop judging others by your own failings. It is well known that fluoros have an overall green cast. It may be well known to you, but you don't have the two lamps near side by side to make a comparison. |
Halogen to be banned
On Thu, 10 Jun 2021 07:48:45 +0100, Mark Carver
wrote: On 09/06/2021 22:51, T i m wrote: On Wed, 9 Jun 2021 15:24:17 +0100, Mark Carver wrote: snip I doubt LEDs will work in our John Lewis 'touch sensitive/three level' bedside lamps. FWIW I put a dimmable LED lamp in mums 'touch sensitive three level' table lamp (and two similar used as bedside lights) and it/they worked fine? I can't imagine it was bought with LED compatibility in mind but it could have been LED compatible of course. Interesting. I'll get an LED replacement bulb, and give it a spin then. They might have been bought from Homebase FWIW. I'm sure the 'guts' all come from the same place in China ! You are probably right, even if they were initially designed here. Cheers, T i m |
Halogen to be banned
In article ,
Fredxx wrote: It means I can make side by side comparison. The LED tubes provide a natural white, where the florries have a magenta tinge, lacking green in comparison. Others have also commented that the LED tubes are brighter. 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. -- *Rehab is for quitters. Dave Plowman London SW To e-mail, change noise into sound. |
Halogen to be banned
In article ,
Tim Streater wrote: On 10 Jun 2021 at 13:27:54 BST, The Natural Philosopher wrote: Kodachrome however, especially 25, was a beautiful - and extremely expensive - film Agree it was beautiful, wouldn't agree it was particularly expensive. I never used anything else and regret its passing. 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. ;-) -- *Keep honking...I'm reloading. Dave Plowman London SW To e-mail, change noise into sound. |
Halogen to be banned
On 10/06/2021 15:17, Tim Streater wrote:
On 10 Jun 2021 at 13:27:54 BST, The Natural Philosopher wrote: Kodachrome however, especially 25, was a beautiful - and extremely expensive - film Agree it was beautiful, wouldn't agree it was particularly expensive. I never used anything else and regret its passing. It was the same price as Kodachrome 64 and Kodachrome 200 in 35mm format from what I remember. |
Halogen to be banned
On 10/06/2021 16:59, Dave Plowman (News) wrote:
In article , Fredxx wrote: It means I can make side by side comparison. The LED tubes provide a natural white, where the florries have a magenta tinge, lacking green in comparison. Others have also commented that the LED tubes are brighter. 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. 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. There are tri-phosphor tubes on the market that are suitable for photography etc where light quality is important. I think you have said this before. I suspect they're expensive? Don't they also degrade over time? |
FreeSat.
On 10/06/2021 09:35, T i m wrote:
Or they try to install it themselves, it mis-tunes to the wrong tx, (How often / easy is that to happen and under what circumstances would you say? I mean, don't the TV's often ask for your location / 'Region TV reception being what it is, the strongest signal might be the wrong signal. If 'automatic' tuning doesn't work because it can be confused by which transmitter(s?) to use, would that mean tuning it manually and what typically happens after when a re-tune is required? They get a grandchild to do it. Bill |
FreeSat.
On 10/06/2021 11:47, Dave Plowman (News) wrote:
Of course if you live in a remote area, you may have a choice of transmitters. A remote area like South Yorkshire, with Crosspool, Emley, Bilsdale, Waltham and Belmont all competing for the TV set's attention! Bill |
Halogen to be banned
On 10/06/2021 13:27, The Natural Philosopher wrote:
Age also makes a difference. I took two bodies on holiday to the Med once, My mind is wondering again. Bill |
FreeSat.
In article ,
williamwright wrote: On 10/06/2021 09:35, T i m wrote: Or they try to install it themselves, it mis-tunes to the wrong tx, (How often / easy is that to happen and under what circumstances would you say? I mean, don't the TV's often ask for your location / 'Region TV reception being what it is, the strongest signal might be the wrong signal. Is that still the case with digital? If 'automatic' tuning doesn't work because it can be confused by which transmitter(s?) to use, would that mean tuning it manually and what typically happens after when a re-tune is required? They get a grandchild to do it. Bill -- *Sorry, I don't date outside my species. Dave Plowman London SW To e-mail, change noise into sound. |
Halogen to be banned
In article ,
Fredxx wrote: On 10/06/2021 16:59, Dave Plowman (News) wrote: In article , Fredxx wrote: It means I can make side by side comparison. The LED tubes provide a natural white, where the florries have a magenta tinge, lacking green in comparison. Others have also commented that the LED tubes are brighter. 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. 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. 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. 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. 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. There are tri-phosphor tubes on the market that are suitable for photography etc where light quality is important. I think you have said this before. I suspect they're expensive? Don't they also degrade over time? 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. -- *If God dropped acid, would he see people? Dave Plowman London SW To e-mail, change noise into sound. |
Halogen to be banned
On 10/06/2021 15:09, Fredxx wrote:
It is well known that fluoros have an overall green cast. It may be well known to you, but you don't have the two lamps near side by side to make a comparison. I think maybe the belief that fluos have a green cast comes from the was film and sensors respond to their spectrum. Bill |
Halogen to be banned
On 10/06/2021 15:17, Tim Streater wrote:
On 10 Jun 2021 at 13:27:54 BST, The Natural Philosopher wrote: Kodachrome however, especially 25, was a beautiful - and extremely expensive - film Agree it was beautiful, wouldn't agree it was particularly expensive. I never used anything else and regret its passing. I thought it was the same price as Kodachrome 64. Bill |
FreeSat.
On 10/06/2021 18:36, Dave Plowman (News) wrote:
TV reception being what it is, the strongest signal might be the wrong signal. Is that still the case with digital? Yes. It might be the wrong region. For example 1. Most of N Yorks gets a stronger Bilsdale than Emley but Emley is the correct region. 2. Some areas of Sheffield get monster signals from Crosspool but they are unreliable due to tree screening, so people tend to use Belmont. 3. Some coastal areas are affected by tidal fading so people tend to use a weaker signal from an inland tx. Bill |
Halogen to be banned
On 10/06/2021 18:45, williamwright wrote:
On 10/06/2021 15:09, Fredxx wrote: It is well known that fluoros have an overall green cast. It may be well known to you, but you don't have the two lamps near side by side to make a comparison. I think maybe the belief that fluos have a green cast comes from the was film and sensors respond to their spectrum. 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: http://www.lamptech.co.uk/Documents/FL%20Phosphors.htm |
FreeSat.
On Thu, 10 Jun 2021 17:37:32 +0100, williamwright
wrote: On 10/06/2021 09:35, T i m wrote: Or they try to install it themselves, it mis-tunes to the wrong tx, (How often / easy is that to happen and under what circumstances would you say? I mean, don't the TV's often ask for your location / 'Region TV reception being what it is, the strongest signal might be the wrong signal. Noted. If 'automatic' tuning doesn't work because it can be confused by which transmitter(s?) to use, would that mean tuning it manually and what typically happens after when a re-tune is required? They get a grandchild to do it. ;-) Or often along this row of cottages, yours truly. ;-) That said, I think I've probably had to re-enable more things that they disabled because of finger trouble on digital systems than I have tuning or re-tuning analogue stuff. Tell me if this sounds familiar ... Ding dong ... Hello yourname, I'm sorry to trouble you again but I think I have broken something on my TV as I was just going to watch what I recorded yesterday and I pressed something and now it's all gone black but would you be able to come along soon and look at it for me and tell me if I need to replace something we are now walking along to hers ... as Cynthia and Joan are coming along at 2 and we are going shopping but I wanted to watch it before they come round as they will want to talk about it and we won't be able if I haven't watched it yet going into their place ... thanks for coming along and I'm sorry to bother you again but I phoned Darren and he said he can come round this evening and look at it for me but oh ... you've got it working ... thank you so much, what would I do without you ... can I give you some cake ... ;-) Cheers, T i m |
Halogen to be banned
"Andrew" wrote in message
... On 10/06/2021 15:17, Tim Streater wrote: On 10 Jun 2021 at 13:27:54 BST, The Natural Philosopher wrote: Kodachrome however, especially 25, was a beautiful - and extremely expensive - film Agree it was beautiful, wouldn't agree it was particularly expensive. I never used anything else and regret its passing. It was the same price as Kodachrome 64 and Kodachrome 200 in 35mm format from what I remember. 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. |
Halogen to be banned
"williamwright" wrote in message
... On 10/06/2021 15:09, Fredxx wrote: It is well known that fluoros have an overall green cast. It may be well known to you, but you don't have the two lamps near side by side to make a comparison. I think maybe the belief that fluos have a green cast comes from the was film and sensors respond to their spectrum. 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. |
Halogen to be banned
In message , ARW
writes On 09/06/2021 19:05, Tim Lamb wrote: In message , Robin writes On 09/06/2021 14:06, Tim Lamb wrote: In message , nightjar writes On 09/06/2021 09:39, ss wrote: ..."Sales of halogen lightbulbs are to be banned in the UK from September, with fluorescent lights to follow, under government climate change plans".... Apart from a few, rarely used, lamps that have yet to be changed, I have long converted everything to LED. *Hmm.. I have about 25 twin 5' florries in my workshop in 4 switched banks. This may be the moment to do the LED conversion. You have plenty of time to find 50 round tuits given they'll be phased out "from Sept 2023 onwards" Huh! Put up with an access tower on bare floor. Place is half full of fixed machinery now. Might be doable with an agile bloke from Doncaster:-) How high? 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:-) -- Tim Lamb |
Halogen to be banned
On 10/06/2021 21:21, NY wrote:
"williamwright" wrote in message ... On 10/06/2021 15:09, Fredxx wrote: It is well known that fluoros have an overall green cast. It may be well known to you, but you don't have the two lamps near side by side to make a comparison. I think maybe the belief that fluos have a green cast comes from the was film and sensors respond to their spectrum. 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 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. |
Halogen to be banned
On 10/06/2021 21:33, Tim Lamb wrote:
In message , ARW writes On 09/06/2021 19:05, Tim Lamb wrote: In message , Robin writes On 09/06/2021 14:06, Tim Lamb wrote: In message , nightjarÂ* writes On 09/06/2021 09:39, ss wrote: ..."Sales of halogen lightbulbs are to be banned in the UK from September, with fluorescent lights to follow, under government climate change plans".... Apart from a few, rarely used, lamps that have yet to be changed, IÂ* have long converted everything to LED. Â*Hmm.. I have about 25 twin 5' florries in my workshop in 4 switchedÂ* banks. This may be the moment to do the LED conversion. You have plenty of time to find 50 round tuits given they'll be phasedÂ* out "from Sept 2023 onwards" Â*Huh! Put up with an access tower on bare floor. Place is half full ofÂ* fixed machinery now. Â*Might be doable with an agile bloke from Doncaster:-) How high? 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 aboutÂ* the rewireable fuses in a 3 phase distribution board:-) So gable end height on a newbild then. There is noting wrong with fuses. -- Adam |
Halogen to be banned
On Wed, 09 Jun 2021 16:35:31 +0100, "Dave Plowman (News)"
wrote: snip I've *just* picked up a high output 5' LED florry replacement for a fitting in the study / workshop but the fitting is electronic so I'm going to have to bypass all the 'guts'. The main reason for doing it isn't (primarily) the light but the hope it will get rid of the mains hum ... ;-( Mains hum from an electronic ballast? Something not right there as they (should) run at a higher frequency to get rid of flicker. 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. https://ibb.co/5WpjQm5 I pulled all the guts out because 1) I could and 2) it won't be going back to florry / hum, 3) it was lighter to hold in place to re-attach under the bed 4) I could re-wire it cleanly with all the crap out of the way and 5) I could clean the fitting easier. ;-) 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). https://www.tlc-direct.co.uk/Products/LTTH527DL.html I might see if I can fit a light deflector taking some of what is currently going backwards and turning it down to the bench but only after I've used it for real and done some fine soldering etc. 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 [1] I wonder if some foil / chrome tape stuck under the bed above the tube would reflect more light back than the white paint? |
Halogen to be banned
Fredxx wrote:
I'm sure the eye response is very different to film emulsion response. Also, which may be relevant here - eye responses differ, sometimes by quite a lot - between people. #Paul |
Halogen to be banned
On 12/06/2021 14:12, #Paul wrote:
Fredxx wrote: I'm sure the eye response is very different to film emulsion response. Also, which may be relevant here - eye responses differ, sometimes by quite a lot - between people. They do indeed. But the relevant blue, red, green cones in eyes have a similar response in terms of wavelength. Where the difference you mention comes from having different proportions of these cones, or even one type missing. |
Halogen to be banned
In article ,
Fredxx wrote: On 12/06/2021 14:12, #Paul wrote: Fredxx wrote: I'm sure the eye response is very different to film emulsion response. Also, which may be relevant here - eye responses differ, sometimes by quite a lot - between people. They do indeed. But the relevant blue, red, green cones in eyes have a similar response in terms of wavelength. Where the difference you mention comes from having different proportions of these cones, or even one type missing. It's interesting to view a narrow spectrum light - like say yellow low pressure sodium - then match it by adjusting the RGB drives to a monitor. No two people will get the same result. -- *How much deeper would the oceans be without sponges? * Dave Plowman London SW To e-mail, change noise into sound. |
Halogen to be banned
On 12/06/2021 18:14, Dave Plowman (News) wrote:
In article , Fredxx wrote: On 12/06/2021 14:12, #Paul wrote: Fredxx wrote: I'm sure the eye response is very different to film emulsion response. Also, which may be relevant here - eye responses differ, sometimes by quite a lot - between people. They do indeed. But the relevant blue, red, green cones in eyes have a similar response in terms of wavelength. Where the difference you mention comes from having different proportions of these cones, or even one type missing. It's interesting to view a narrow spectrum light - like say yellow low pressure sodium - then match it by adjusting the RGB drives to a monitor. No two people will get the same result. Is your experience is with CRT? These are associated with poor purity wrt to LCD http://www.marcelpatek.com/LCD.html I would wager, if you have a 'pure' green LED light mixed with a 'pure' red LED I suspect the difference would be somewhat less for the average observer, except those who are truly missing a set of cones or someone who cannot distinguish between red and green. BICBW |
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