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Model Forum / General / Railroads / February 2010Metamerism
If ever you are tempted to damn a manufacturer for not reproducing colours accurately, it may be you who is at fault: http://en.wikipedia.org/wiki/Metamerism_%28color%29 MBQ In article <47058904-240e-4fe6-9941-733b94d593af@b2g2000yqi.googlegroups.com>, "manatbandq@hotmail.com" <manatbandq@hotmail.com> writes >If ever you are tempted to damn a manufacturer for not reproducing >colours accurately, it may be you who is at fault: > >http://en.wikipedia.org/wiki/Metamerism_%28color%29 > >MBQ Nope, it's still the manufacturer's fault for not using paint that's not spectrally colour matched (see last para). In theory, using the same pigment as the original should do that, though some pigments may be no longer available, and I suppose the medium could have some effect. David  SignatureDavid Littlewood > In article > <47058904-240e-4fe6-9941-733b94d59...@b2g2000yqi.googlegroups.com>, [quoted text clipped - 9 lines] > Nope, it's still the manufacturer's fault for not using paint that's not > spectrally colour matched. Given the stories of how colours were actually mixed and applied (not the theory), that's simply not possible IMHO. MBQ > In article > <47058904-240e-4fe6-9941-733b94d593af@b2g2000yqi.googlegroups.com>, [quoted text clipped - 12 lines] > > David The primary factors in colour perception are a) your physiological quirks and glitches; and b) the ambient light. Regarding a), the only thing we can ever be sure of that we see the same (or at least closely similar) colour _differences_. We may infer that we see more or less the same colours, ie, that the experience of colour is generally the same for us all, but objectively, we can test only the perception of differences. (BTW, women in general can discriminate finer colour differences than men.) Regarding b), this is so complicated that we all make mistakes, mostly because we confuse our perception of colour with the objective reality. People often talk as if seeing a colour outdoors will give them a true impression, forgetting that the objects in question (clothes, train models) often aren't intended for use outdoors, and in any case it's unlikely that they'll be seen in exactly the same weather and lighting conditions in which they were tested for their "true" colour. There's another, somewhat counterintuitive, factor: we see the colours we expect to see, even when the ambient light does not provide a full spectrum, or the paint composition doesn't reflect the correct mix of colours. Only in severely deficient light (eg from mercury vapour lamps) do we realise that we are seeing some colours incorrectly. Most of the time, we correct our perception of the colours, even the colours in shadows, which are spectrally not the more or less neutrally grayed colours we perceive. The visual cortex is remarkably subtle creator of illusions, all of them unnoticed almost all the time, because they serve to create a "correct" image of the world around us. Once in a while, we do notice these corrective illusions, and then we marvel at the weirdness of the world. We should perhaps rather marvel how much of that weirdness we eliminate without being aware that we do so. cheers, wolf k. >> In article >> <47058904-240e-4fe6-9941-733b94d593af@b2g2000yqi.googlegroups.com>, [quoted text clipped - 47 lines] > cheers, > wolf k. Most colour pigments used in the past faded with age, so any given steam loco or passenger carriage would vary year by year. (actually, quite a lot of Diseasals have done that as well :-) Some colours were more prone than others to rapid fading. If we painted our models in precisely the shades the prototype left the works as, we would be wrong for most of the working life of that item. Add to that the fact that colours look lighter with distance - 76' away looks appreciably lighter than at 1' ... There are so many variables that any shade lighter than original will be right at some point between prototype repaints ;-) Greg.P. (nobody mention black) >>> In article >>> <47058904-240e-4fe6-9941-733b94d593af@b2g2000yqi.googlegroups.com>, [quoted text clipped - 62 lines] > Greg.P. > (nobody mention black) Thats why I prefer the Hornby colours and finish on their locos to Bachmann. Bachmann look as though just been painted/varnished whereas Hornby more well cleaned. Cheers, Simon >>> In article >>> <47058904-240e-4fe6-9941-733b94d593af@b2g2000yqi.googlegroups.com>, [quoted text clipped - 63 lines] > Greg.P. > (nobody mention black) I reckon there's a lot of room for subjectivity with colours. About a month ago I painted an Express Parcels SPV with Railmatch aerosol BR blue. It looks just the part. Yesterday I put the final coat on a 08, and it looks way too dark - despite both having a coat of primer, and then 4 coats of blue (I go very carefully with spray paint!). If I take a photo of the two, they look the same, but something (amount of details maybe) makes the 08 look darker. It could be brass vs. plastic I suppose! I've also noticed a number of BR blue preserved diesels where the yellow is completely wrong (far too yellow if you see what I mean), particularly one at High Peak. The trouble is I'm a bit dubious about relying on photo's these days, unless there is a something to reference against, as so many are messed about with to make the photo look nice rather than be an accurate record. Just some random thoughts! Cheers Richard SignatureI have become...............comfortably numb [...] > If I take a photo of the two, they look the same, but something (amount > of details maybe) makes the 08 look darker. It could be brass vs. plastic > I suppose! Well, if you sued the same primer on both models, there shouldn't be that much visible difference. OTOH, even a small difference in objective shade or tone can translate into a large difference in how the camera and the human see colours. Firstly, we see much wider range of light and dark than film or electronic sensors do. Thus, a small difference in shade can become a large difference when photographed. Secondly, there is automatic correction of tone, hue, and shade to make "the same colours" actually look the same. This correction starts in the eye. By the time this automatic correction system has finished its work on the inputs, you will see more or less what you expect to see, in this case an 08 and an SPV that are the same colour. Or close to it. > I've also noticed a number of BR blue preserved diesels where the yellow > is completely wrong (far too yellow if you see what I mean), particularly > one at High Peak. IMO, that's because they are painted using aged oil-based colour chips for reference. But those chips (stored in cupboards etc) have darkened with age (that's also the reason "old masters" paintings have darkish all over tone.) What we mostly recall is working locos. The yellow faded _very_ quickly. Well, actually, the medium breaks down, and a thin layer of semi-opaque whitish dust overlays the yellow, if you want to be technical. > The trouble is I'm a bit dubious about relying on photos these days, > unless there is a something to reference against, as so many are messed > about with to make the photo look nice rather than be an accurate record. You're quite right to be dubious, and I think you should be even more dubious about old photographs. What you recall and what the camera saw are quite different. Film is even more sensitive to differing ambient light than digital. Digital cameras have software that corrects the "white balance". All current cameras have settings for different kinds of light sources, too. So in fact, a digital image is, in one sense, more correct than a film image. > Just some random thoughts! > > Cheers > Richard IMO, many modellers fuss too much about the "correct" colours. cheers, wolf k. >>>> In article >>>> <47058904-240e-4fe6-9941-733b94d593af@b2g2000yqi.googlegroups.com>, [quoted text clipped - 88 lines] > Cheers > Richard Try modelling pre-grouping - that way you will never know if you are wrong (therefore you are presumably right) but you can still argue with the terminally pedantic. ;-) >>>>> In article >>>>> <47058904-240e-4fe6-9941-733b94d593af@b2g2000yqi.googlegroups.com>, [quoted text clipped - 96 lines] > the terminally pedantic. > ;-) Oh I don't know, there's "experts" on everything out there......;-) I'm not a steam type, but I do have a sneaky desire to build a 9F ( I had one on my all diesel 00 layout when Hornby first made them). If I ever do build one I will paint it like chap on NRM forum - BR blue, with the Arrows Of Indecision on the smoke deflectors. Because it looks nice. And as a bonus it would annoy the purists ;-) SignatureI have become...............comfortably numb >> Try modelling pre-grouping - that way you will never know if you are >> wrong (therefore you are presumably right) but you can still argue with [quoted text clipped - 8 lines] >Arrows Of Indecision on the smoke deflectors. Because it looks nice. And >as a bonus it would annoy the purists ;-) That would be Just Wrong. The Arrows need to be white or silver, and wouldn't show up at all well on yellow smoke deflectors. Large Logo, of course... Someone had a load of such pix (Can I find them? No...), and ISTR that Network SE suited the Spam Can rather well. Tim >>> Try modelling pre-grouping - that way you will never know if you are >>> wrong (therefore you are presumably right) but you can still argue with [quoted text clipped - 18 lines] > > Tim I found it difficult painting pre-grouping passenger livery, which is why my Big Layout was a freelance light railway (drawing on the Madder Valley and the Garstand and Knot End Rly), that way I could use simplified livery for the coaches, this also meant I could use outside cylinder chassis from continental engines which at the time were better runners). Regards Mike >There are so many variables that any shade lighter than original will be >right at some point between prototype repaints ;-) Exactly! A swiss photo of mine demonstrates this rather well <http://www.erstfeld.co.uk/Switzerland/Switzerland-Miscellaneous/8481536_xHsiH#78 6187028_baYvY> although clearly there is a dirt effect here as well as fading! >>There are so many variables that any shade lighter than original >>will be [quoted text clipped - 5 lines] > > although clearly there is a dirt effect here as well as fading! I am wondering if the whole perception of colour rendition is down to our ageing.A few weeks ago I saw something on telly about eyesight and how the level of lighting needs to be increased as you get older. When you are aged 40 to 55 you need twice the amount of lighting as before 40 and above 55 you need three times. It also said that so many bulbs do not give you the same brilliance as sunlight. Strip lights are one of the best light sources but I know this affects a lot of people because of the slight "flicker". Another factor that a lot of people do not realise is that net curtains subdue a lot of the suns natural light which can be up to one of the ageing factors. Another factor that is seriously affecting our perception of colour is the amount of TV screens and computer monitors that are not now correctly set. A friend of mine worked at a television tube manufacturer a good few years ago and they had reference photographs to set the correct colour balance of a device. In the old days we used to have the colour test card displayed on the TV screen whenever there was not transmission of programs and there were reference photographs to set the correct colour balance/lighting. Progress has improved things but some standards have diminished. Ian Robinson > <Nigel Emery> wrote... >> [quoted text clipped - 27 lines] > to set the correct colour balance/lighting. > Progress has improved things but some standards have diminished. Many people do not read the instructions on how to set up their TV for different types of prgramming and different levels of room lighting. They are often set up to look good in a brightly-lit store alongside other screens, and may be too bright and saturated for home viewing. SignatureMartin S. >> <Nigel Emery> wrote... >>> [quoted text clipped - 32 lines] > They are often set up to look good in a brightly-lit store alongside > other screens, and may be too bright and saturated for home viewing. Way back when I first got colour TV, one of the first things I noticed was that in general UK colour programmes had 'more realistic' colours than US colour programs, which tended towards the gaudy. Greg.P. NZ >>> <Nigel Emery> wrote... >>>> [quoted text clipped - 39 lines] > Greg.P. > NZ NTSC was always a bit problematic, when the Germans developed PAL things improved a fair bit and the UK was lucky in being late to the party as we got to pick. Regards Mike >>>> <Nigel Emery> wrote... >>>>> [quoted text clipped - 58 lines] > things improved a fair bit and the UK was lucky in being late to the > party as we got to pick. NTSC stands for "Never the same colour", so popular rumour has it. > Regards > > Mike >>>>> <Nigel Emery> wrote... >>>>>> [quoted text clipped - 60 lines] >> > NTSC stands for "Never the same colour", so popular rumour has it. NTSC2, which replaced NTSC decades ago, stands for "Never The Same Colour Twice". >>>>>> <Nigel Emery> wrote... >>>>>>> [quoted text clipped - 4 lines] >>>>>>> >>>>>>> <http://www.erstfeld.co.uk/Switzerland/Switzerland-Miscellaneous/8481536_xHsiH#78 6187028_baYvY> although >>>>>>> clearly there is a dirt effect here as well as fading! >>>>>> [quoted text clipped - 54 lines] > NTSC2, which replaced NTSC decades ago, stands for "Never The Same > Colour Twice". If I remember from my Telecomm courses, when NTSC signal was weak, the colour would change whilst for PAL in the same circumstance, only the depth of the colour changes. Thus PAL copes with poor signals much better than NTSC. David > "Greg.Procter" <procter@ihug.co.nz> wrote... >>>> <Nigel Emery> wrote... [quoted text clipped - 44 lines] > things improved a fair bit and the UK was lucky in being late to the > party as we got to pick. Apparently, NTSC is unable to reproduce a pure red. The advent of ATSC HD has improved things considerably. SignatureMartin S. >>>> <Nigel Emery> wrote... >>>>> [quoted text clipped - 44 lines] > improved a fair bit and the UK was lucky in being late to the party as > we got to pick. Does it relate to NTSC? We have PAL here in NZ as we started later than everyone else (1961 I think) Programmes for the next twenty years at least must have arrived here in photographic film format. Greg.P. >>>>> <Nigel Emery> wrote... >>>>>> [quoted text clipped - 50 lines] > > Greg.P. Complicated question, there are lots of flavours of NTSC and PAL, then there is the French SECAM system and whatever the Chinese have developed. On the ships we had multi-standard TVs with a bank of switches on the back and part of my job was setting these up as we reached port. Kiwi and Aussie PAL is slightly different from UK PAL but I cannot now remember what the difference is (possibly the offset for the audio - too long ago to remember the details). We used to get the Word Radio and TV Handbook which listed the setting for each country, it's probably all available on line now but it's late and I'm tired to too tired to run it through a search engine (Ask may be better than Google as its a techie question). Regards Mike >>>>>> <Nigel Emery> wrote... >>>>>>> [quoted text clipped - 77 lines] > > Mike My point was that TV programmes at the time I was commenting on came to NZ as film stock, not in analogue or digital formats, so formats should have made no difference. Worked in TV export and repair in the early 1970s (managerial) and in shipping 1970s-1980s. Greg.P. >>>>>>> <Nigel Emery> wrote... >>>>>>>> [quoted text clipped - 85 lines] > > Greg.P. Sorry - got it (finally). Not sure why the film stock versions would differ, but I know a chap who may have some insight, I'll ask. Regards Mike > >>>>> <Nigel Emery> wrote... > [quoted text clipped - 67 lines] > > - Afficher le texte des messages précédents - As I recall UK pal has the sound on the other sideband from the antipodes chaps. As I recall UK pal has the sound on the other sideband from the antipodes chaps. ----- Ah, just like the water goes down the plughole the other way down here. SignatureRegards John > >> <Nigel Emery> wrote... > [quoted text clipped - 41 lines] > > - Afficher le texte des messages précédents - I have long wondered why the yanks insist on people being a universal yellow/brown and everything else with a green halo. Goodness knows why they stick to their rather inadequate colour system! Peter On 12 fv, 01:15, "Greg.Procter" <proc...@ihug.co.nz> wrote: > > "Ian" <ianp.robin...@blueyonder.co.uk> wrote: > >> <Nigel Emery> wrote... [quoted text clipped - 57 lines] > > - Afficher le texte des messages prcdents - > I have long wondered why the yanks insist on people being a universal > yellow/brown and everything else with a green halo. Goodness knows why > they stick to their rather inadequate colour system! Probably because it would cost them too much to change. Anyway, aren't we all supposed to be going to HD TV? There will probably be several different systems for that, with the Yanks going to an inadequate system they invented, the French going to another system just to be French and different, whereas the rest of the world goes for the best available at the time. > Peter SignatureJane OO/HO and DCC in the garden http://www.janesullivan.webspace.virginmedia.com/railway/railway.html > On 12 fv, 01:15, "Greg.Procter" <proc...@ihug.co.nz> wrote: >> > "Ian" <ianp.robin...@blueyonder.co.uk> wrote: [quoted text clipped - 71 lines] > to be French and different, whereas the rest of the world goes for the > best available at the time. You mean like we all went to Beta video recording? Regards, Greg.P. >> >> <Nigel Emery> wrote... >> [quoted text clipped - 49 lines] > > Peter Not Invented Here SignatureI have become...............comfortably numb >>>>> <Nigel Emery> wrote... >>>>>>> There are so many variables that any shade lighter than original [quoted text clipped - 39 lines] >> yellow/brown and everything else with a green halo. Goodness knows why >> they stick to their rather inadequate colour system! ???? Not on my TV! Of course, I actually adjust the colours to suit me. The source material (film, analog, digital) determines the colours, even with "colour correction" applied by the broadcaster (or whoever transfers the material to disc.) Eg, BBC shows were invariably washed out, looking a lot like old colour tinted b/w photos. Now that it's all digitised, the colours are much more natural. The default colour palette is adjusted (if that's the word) to provide relatively inoffensive colours from a wide variety of sources. Which means that none of it's pleasing. >> Peter > > Not Invented Here Google brought me this: http://en.wikipedia.org/wiki/High-definition_television Check out the links to Extreme High Definition and Super High Vision. FWIW, I have 1680x1050 native resolution LCD monitor for this computer. Very nice. Our TV is a Sony Bravia 42" 1080p. _Very_ nice! Lots of adjustments for aspect ratio, sound, and colour. SD material (VHS tape, DVDs) looks much clearer on it, too. Highly recommended, if you're thinking of a new entertainment toy. ;-) Haven't sprung for a BluRay player and probably won't. A couple of friends have told me you need at least a 60" panel to see the difference between standard DVD and BluRay. cheers, wolf k. >>>>>> <Nigel Emery> wrote... >>>>>>>> There are so many variables that any shade lighter than [quoted text clipped - 70 lines] > need at least a 60" panel to see the difference between standard DVD > and BluRay. BluRay players are now under C$200. There is a difference if you look closely, but probably not from 10-15ft away. SignatureMartin S. [....] >> FWIW, I have 1680x1050 native resolution LCD monitor for this >> computer. Very nice. Our TV is a Sony Bravia 42" 1080p. _Very_ nice! [quoted text clipped - 7 lines] > BluRay players are now under C$200. There is a difference if you look > closely, but probably not from 10-15ft away. Still too high. Once they get around $50, I'll think about BluRay again, maybe. Watched the new Star Trek movie last night (a gift from daughter and son-in-law). Well done alternative time line. Looks like it could be a good series, if they make the characters more complex. No trains, though. ;-( wolf k. >> BluRay players are now under C$200. There is a difference if you look >> closely, but probably not from 10-15ft away. > > Still too high. Once they get around $50, I'll think about BluRay again, > maybe. I remember paying $500 for a Mitsubishi VHS VCR, circa 1988. And the same for a 20" Viking colour TV from Eaton's in 1974. SignatureMartin S. >>> BluRay players are now under C$200. There is a difference if you look >>> closely, but probably not from 10-15ft away. [quoted text clipped - 3 lines] > I remember paying $500 for a Mitsubishi VHS VCR, circa 1988. > And the same for a 20" Viking colour TV from Eaton's in 1974. I remember my room mate buying a 13" b/w TV for $300 in 1956. $2,000 to $3,000 in today's money (depending on how you calculate inflation.) Which permits a segue into model railways: Many people whinge about the high prices of model railways. They flinch when they see an F7 diesel with DCC and sound offered at around $200. But allowing for inflation, most models and kits are well within the price range of the 1950s, and many are are cheaper. Besides, quality and technology have improved, so that the price-quality ratio is much better than way back when. Eg, that DCC sound equipped loco at $200 IMO compares very favourably with a plain vanilla F7 loco _kit_ costing about $20 in the mid-50s. That improvement in price-quality ratio is one reason that kit and scratchbuilding are now a niche market. Model builders are well served these days, but most model railway enthusiasts are happy that so many high quality ready to run models are available. cheers, wolf k. SNIP... FWIW, I have 1680x1050 native resolution LCD monitor for this computer. Very nice. Our TV is a Sony Bravia 42" 1080p. _Very_ nice! Lots of adjustments for aspect ratio, sound, and colour. SD material (VHS tape, DVDs) looks much clearer on it, too. Highly recommended, if you're thinking of a new entertainment toy. ;-) Haven't sprung for a BluRay player and probably won't. A couple of friends have told me you need at least a 60" panel to see the difference between standard DVD and BluRay. cheers, wolf k. ======================================= Still got Sony TV bought over 14 years ago. Occasionally think about a new one but find it difficult to justify it. Anyway as only watch childrens TV and occasional re-run of the Sweeney doesnt seem worth it. Cheers, Simon > I have long wondered why the yanks insist on people being a universal > yellow/brown and everything else with a green halo. Goodness knows why > they stick to their rather inadequate colour system! "After over a half-century of use, the vast majority of over-the-air NTSC transmissions in the United States were replaced with ATSC on June 12, 2009, and will be, by August 31, 2011, in Canada." http://en.wikipedia.org/wiki/NTSC SignatureMartin S. >>There are so many variables that any shade lighter than original will be >>right at some point between prototype repaints ;-) [quoted text clipped - 4 lines] > > although clearly there is a dirt effect here as well as fading! As was saying the other day, colour especially in weathering and adding rust should always change shade gradually merging from one to another over a distance. Tonight was looking at a colour photo of an ex wd 2-8-0 in old backtrack that has large patch of rust on smokebox that looks as if its been painted on, has sharply defined edge with no transition whatsoever. Few other patches around, not as dramatic but also well defined edges. What do I know ? If had seen someones model weatherd like that would have smiled knowingly think oh dear.... Suggest work from photos of what you would expect rather than just any example. Cheers, Simon >>> There are so many variables that any shade lighter than original will >>> be [quoted text clipped - 17 lines] > Suggest work from photos of what you would expect rather than just any > example. Obviously one needs a little photograph wallet by the layout with copies of the photographs one sourced in weathering one's locos. :-) Greg.P. |
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