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#1
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Bit of a con, really ... ?
In article ,
Arfa Daily wrote: snip There's no need for a display since it is theoretically possible to get all visible colours from RGB. Mixing dyes is a different matter. Theory, remembered from many years ago, suggests that isn't quite true. I seem to recall my colour TV lecturer at college, spending a whole session on 'the chromaticity diagram', and then explaining that there were certain 'non-spectral' colours such as brown, which could not be created by an additive mix of R,G and B, and any brown that was seen on the screen was actually some kind of orange or red, which was *perceived* as brown because of the surrounding colours, and other visual cues. That might not be exactly it, as this was all learnt nearly 40 years ago, but something close, I think. Think that was more to do with the deficiencies of the then tube colour cameras. Three or four tubes - usually Plumblicons. Which would show Magenta as bright green, etc. And of course many CRT sets didn't use the best phosphors - more concerned with how bright they'd go. As to whether LEDs as backlights do a good job, I'm sure that they must be at least as good as CCFLs at colour rendering, otherwise, the manufacturers wouldn't be making such a thing about it. Heh heh - advertising? I play with LEDs quite a bit, and they are getting better but still don't give as good a light quality as the best fluorescents. Flesh tones look perfectly fine on digital cameras which use LED backlit displays. Flesh tones contain a vast range of colour shades even on the one face - unless it's Des O'Connor's makeup. Wasn't talking about a quick glance. My whole issue with this, was that the LED 'angle' was being pushed by wording that *suggested* it was the main display technology rather than an LCD panel which it actually is, and which the great unwashed are now familiar with. That seemed to me to be a deliberate attempt to mislead people into believing that it was something new and revolutionary - as SED technology will be if it ever gets on the market, or OLED if they can get it big enough. Well yes and I agree. They're pushing them on TV too. But I haven't actually seen one. Perhaps they are as good as claimed. Cynical me doubts it. I don't have a problem with them claiming that this backlighting technique is revolutionary in TV sets - it is - and even claiming a reduction in power, if that's true, for a leg-up on the eco-bollox ladder, but I really think that they should be making that distinction, rather than trying to bamboozle prospective buyers with questionable use of terminology which punters are likely to have heard of, but won't actually understand. On the power consumption issue, I still do not feel that this technology is likely to consume anything like as much as the 100 or so watts that CCFL backlighting does. The developments in the light output of narrow-angle LEDs over the last couple of years is staggering. Some of the 1 and 3 watt types could literally blind you. I believe that some cars are now starting to use LED headlamps. It would be interesting to see how they stack up against the 50 watt consumption of 'standard' headlamp bulbs. More to the point to compare with HID in cars? Thing is for domestic light my preference is halogen, quality wise. Expensive fluorescent tubes can match that well enough. CFLs not. Nor any LED I've yet tried. -- *The severity of the itch is proportional to the reach * Dave Plowman London SW To e-mail, change noise into sound. |
#2
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
"Dave Plowman (News)" wrote in message ... In article , Arfa Daily wrote: snip There's no need for a display since it is theoretically possible to get all visible colours from RGB. Mixing dyes is a different matter. Theory, remembered from many years ago, suggests that isn't quite true. I seem to recall my colour TV lecturer at college, spending a whole session on 'the chromaticity diagram', and then explaining that there were certain 'non-spectral' colours such as brown, which could not be created by an additive mix of R,G and B, and any brown that was seen on the screen was actually some kind of orange or red, which was *perceived* as brown because of the surrounding colours, and other visual cues. That might not be exactly it, as this was all learnt nearly 40 years ago, but something close, I think. Think that was more to do with the deficiencies of the then tube colour cameras. Three or four tubes - usually Plumblicons. Which would show Magenta as bright green, etc. And of course many CRT sets didn't use the best phosphors - more concerned with how bright they'd go. Well no, I don't think it was. Take a look at http://www.yorku.ca/eye/nonspect.htm which explains pretty much what I remember. The example of brown is quite a good one, even with it shown in isolation - i.e. with no surrounding colours and no visual cues. As an example of that, if it was a picture of a turd, your brain might very reasonably *expect* it to be brown ... As to whether LEDs as backlights do a good job, I'm sure that they must be at least as good as CCFLs at colour rendering, otherwise, the manufacturers wouldn't be making such a thing about it. Heh heh - advertising? I play with LEDs quite a bit, and they are getting better but still don't give as good a light quality as the best fluorescents. Flesh tones look perfectly fine on digital cameras which use LED backlit displays. Flesh tones contain a vast range of colour shades even on the one face - unless it's Des O'Connor's makeup. Wasn't talking about a quick glance. No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Contrary to what you believe about the phosphors on CRTs, I don't believe that there has been any significant change in their colour rendition capabilities since the earliest delta gun tubes in the uk, which I worked with from about 1970. Even back then, if you put in the time to ensure that the decoder was correctly adjusted, and the CRT colour balance and tracking was correctly set, they had the ability to render flesh tones superbly. In fact this criterion was the main one we used to subjectively evaluate the performance of a set, and was one of the main reasons for the broadcasters using a little girl, whose skin was 'natural' and had no makeup, on test card F. In contrast (no pun intended !) I think that the colour rendition of most LCD TV sets - particularly in the case of flesh tones, is nothing less than dreadful. So if LED backlighting improves on this - and the case of the camera viewfinder images would tend to support this view - then that will be good. My whole issue with this, was that the LED 'angle' was being pushed by wording that *suggested* it was the main display technology rather than an LCD panel which it actually is, and which the great unwashed are now familiar with. That seemed to me to be a deliberate attempt to mislead people into believing that it was something new and revolutionary - as SED technology will be if it ever gets on the market, or OLED if they can get it big enough. Well yes and I agree. They're pushing them on TV too. But I haven't actually seen one. Perhaps they are as good as claimed. Cynical me doubts it. I don't have a problem with them claiming that this backlighting technique is revolutionary in TV sets - it is - and even claiming a reduction in power, if that's true, for a leg-up on the eco-bollox ladder, but I really think that they should be making that distinction, rather than trying to bamboozle prospective buyers with questionable use of terminology which punters are likely to have heard of, but won't actually understand. On the power consumption issue, I still do not feel that this technology is likely to consume anything like as much as the 100 or so watts that CCFL backlighting does. The developments in the light output of narrow-angle LEDs over the last couple of years is staggering. Some of the 1 and 3 watt types could literally blind you. I believe that some cars are now starting to use LED headlamps. It would be interesting to see how they stack up against the 50 watt consumption of 'standard' headlamp bulbs. More to the point to compare with HID in cars? Why particularly ? I was just trying to draw a comparison as to the relative efficiencies of a 'standard' 50 watt halogen headlamp bulb, which we all have a pretty fair idea of the brightness of, and the same thing in a LED version, which is likely to be at least as bright, if not brighter, otherwise there would be no point in the manufacturers trying to use them. If the LED equivalent power consumption was say 10 watts, then we would know that LED backlighting of LCDs was likely going to be more efficient than CCFL backlighting, which we already know consumes around 100 watts to light a 32" screen. If on the other hand the LED equivalent power was 50 or 75 watts, then we would know that it was going to be no better, and possibly worse. Thing is for domestic light my preference is halogen, quality wise. Expensive fluorescent tubes can match that well enough. CFLs not. Nor any LED I've yet tried. Agreed all four points Arfa -- *The severity of the itch is proportional to the reach * Dave Plowman London SW To e-mail, change noise into sound. |
#3
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
In article , Arfa Daily
wrote: Contrary to what you believe about the phosphors on CRTs, I don't believe that there has been any significant change in their colour rendition capabilities since the earliest delta gun tubes in the uk, which I worked with from about 1970 Oh, but there was. The original delta gun shadow mask tubes used the correct NTSC phosphors. Which gave a pretty pure red. The rot really came in with PIL tubes which used a very 'orange' red phosphor simply because it allowed a brighter picture. And that had real implications to flesh tones. Took many years before that was corrected. -- *We have enough youth, how about a fountain of Smart? Dave Plowman London SW To e-mail, change noise into sound. |
#4
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
"Dave Plowman (News)" wrote in message ... In article , Arfa Daily wrote: Contrary to what you believe about the phosphors on CRTs, I don't believe that there has been any significant change in their colour rendition capabilities since the earliest delta gun tubes in the uk, which I worked with from about 1970 Oh, but there was. The original delta gun shadow mask tubes used the correct NTSC phosphors. Which gave a pretty pure red. The rot really came in with PIL tubes which used a very 'orange' red phosphor simply because it allowed a brighter picture. And that had real implications to flesh tones. Took many years before that was corrected. -- *We have enough youth, how about a fountain of Smart? Dave Plowman London SW To e-mail, change noise into sound. Hmmm. I can't say that I remember slot mask / in line tubes producing any worse a picture, in terms of colour rendition, than deltas. Certainly, they were an improvement in convergence and extremity focus - perhaps even overall 'sharpness'. If the colour / output of the red phosphor did not match the transmitted weighting factor for that colour, I would have thought that this would have caused serious problems for rendering whites and greys correctly, and would have had a significantly pronounced effect on the ability of the tube to render subtleties such as flesh tones. An 'orangy' red would have screwed about with the chromaticity diagram, and completely altered the pallette of colours that the tube *could* produce from just three primaries. It would be like taking a printer's pantone colour chart, and redefining all the hues, wouldn't it ? We had some pretty fussy customers back then with serious pots of money, and I can't recall any colour accuracy issues ever arising - aside from one particular customer who used to complain on a weekly basis that colours were "bleeding through" (convergence issues !) and in the summer that there was something wrong because the grass in front of the wicket on the cricket, was yellow ... Nor can I recall any mention of this either in the trade press, or at our company's training school, which was recognised as being one of the best that there was. Anyway, going back to chromaticity diagrams, did you look at the link to an explanation of 'non-spectral colours' to see what I was talking about, outside of any differences which there may or may not have been with the phosphor colours ? Arfa |
#5
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
"Arfa Daily" wrote in message ... No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. There are only a few that use electronic viewfinders and they are low end. |
#6
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
"Dave Plowman (News)" wrote in message
... In article , Arfa Daily wrote: Contrary to what you believe about the phosphors on CRTs, I don't believe that there has been any significant change in their colour rendition capabilities since the earliest delta gun tubes in the uk, which I worked with from about 1970 Oh, but there was. The original delta gun shadow mask tubes used the correct NTSC phosphors. Which gave a pretty pure red. The rot really came in with PIL tubes which used a very 'orange' red phosphor simply because it allowed a brighter picture. And that had real implications to flesh tones. Took many years before that was corrected. I would almost bet my life that this is absolutely backwards -- it was the original phosphors that were orangish, improving only with the rare-earth phosphors of the early '60s. (I remember Sylvania's radio ads.) In fact, I'm pretty certain that most of what's being posted about color TV and color analysis/reproduction is utter bilge. But I don't have a comprehensive understanding of this material (it's not easy), so I'm pretty much keeping my mouth shut. |
#7
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Bit of a con, really ... ?
"dennis@home" wrote in message ... "Arfa Daily" wrote in message ... No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. There are only a few that use electronic viewfinders and they are low end. I'm pretty sure that one of them told me that his camera was over a grand's worth, so I wouldn't call that particularly low end, although I am sure there are others more expensive. If they do not have an LCD panel on them to at least review the pictures you have taken, without having to plug the thing into a computer, that rather defeats the object of it being a portable 'digital' camera, doesn't it ? Even the 3 grand offering on this page has a 3" LCD http://www.calumetphoto.co.uk/Digita...utm_medium=cpc Perhaps I am not being quite accurate in calling it a "viewfinder". I accept that the higher end cameras have a proper optical viewfinder operating on the SLR mirror / prism system, but the LCD panel also serves as a supplementary viewfinder, as well as a display medium for photos already taken. Arfa |
#8
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Bit of a con, really ... ?
Perhaps I am not being quite accurate in calling it a "viewfinder". I
accept that the higher end cameras have a proper optical viewfinder operating on the SLR mirror / prism system, but the LCD panel also serves as a supplementary viewfinder, as well as a display medium for photos already taken. Several DSLRs have live LCD viewing, which could be considered a viewfinder, as it serves the same function. I recently purchased such a camera (though not for that reason). I haven't checked skin tones, but the color rendition is not obviously "off". Perhaps I'll drag out my Macbeth color checker and compare under noon daylight -- the next time we have any in Seattle. One of the best uses for the LCD panel is to confirm the camera's color-temperature setting. It's particularly useful when fine-tuning the green-magenta axis under fluorescent light. As I write this, I'm watching CNN on my cheap-but-good 32" Vizio. Most are perhaps slightly "warmer" than they should be. Not having the original flesh for comparison, I can't know for sure. |
#9
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
In article ,
William Sommerwerck wrote: Oh, but there was. The original delta gun shadow mask tubes used the correct NTSC phosphors. Which gave a pretty pure red. The rot really came in with PIL tubes which used a very 'orange' red phosphor simply because it allowed a brighter picture. And that had real implications to flesh tones. Took many years before that was corrected. I would almost bet my life that this is absolutely backwards -- it was the original phosphors that were orangish, improving only with the rare-earth phosphors of the early '60s. (I remember Sylvania's radio ads.) Colour TV didn't arrive in the UK 'till the late '60s. PIL tubes were some years after that. In fact, I'm pretty certain that most of what's being posted about color TV and color analysis/reproduction is utter bilge. But I don't have a comprehensive understanding of this material (it's not easy), so I'm pretty much keeping my mouth shut. Quite a bit of what I'm saying comes from working in TV production - although I'm on the sound side. But hear plenty from those who work on the vision side of things. ;-) And it was certainly the case that Grade 1 picture monitors continued with delta gun tubes long after PIL were introduced domestically - and stuck with the original NTSC phosphors. As this was the standard the cameras were 'calibrated' to. -- *Can fat people go skinny-dipping? Dave Plowman London SW To e-mail, change noise into sound. |
#10
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Bit of a con, really ... ?
On May 13, 12:31*pm, "dennis@home"
wrote: "Arfa Daily" wrote in message ... No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. And your posts use smoke and mirrors. |
#11
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
In fact, I'm pretty certain that most of what's being posted about color
TV and color analysis/reproduction is utter bilge. But I don't have a comprehensive understanding of this material (it's not easy), so I'm pretty much keeping my mouth shut. Quite a bit of what I'm saying comes from working in TV production - although I'm on the sound side. But hear plenty from those who work on the vision side of things. ;-) And it was certainly the case that Grade 1 picture monitors continued with delta gun tubes long after PIL were introduced domestically -- and stuck with the original NTSC phosphors. As this was the standard the cameras were 'calibrated' to. But there was no "original" NTSC red phosphor -- just a standard for it, that the original red phosphors didn't meet. I /remember/ this from 45 years ago. (I read "Radio-Electronics" and "Electronics World".) The available red phosphor was not very efficient, and when driven hard, it turned "orangey" at high current levels. As for any differences between professional and consumer CRTs... It's true that consumer CRTs were often designed for brightness * (rather than color accuracy or gamut). About 15 years ago, Mitsubishi brought out a consumer CRT with "filtered" phosphors that more-closely approached the NTSC standard ** -- at the expense of brightness. The sets using it quickly flopped, because (at least then) people were more interested in brightness than clarity. * The default setting for most LCD and plasma sets is the "burn the viewer's eyes" mode. ** The closer a primary is toward the edges of the chromaticity diagram, the more saturated it is (ie, the less its output is diluted with white) -- and it's therefore less bright. |
#12
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Bit of a con, really ... ?
Arfa Daily wrote:
We had some pretty fussy customers back then with serious pots of money, and I can't recall any colour accuracy issues ever arising - aside from one particular customer who used to complain on a weekly basis that colours were "bleeding through" (convergence issues !) and in the summer that there was something wrong because the grass in front of the wicket on the cricket, was yellow ... LOL. It didn't occur to him that well trampled grass, in summer, is often yellow? -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- |
#13
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
dennis@home wrote:
"Arfa Daily" wrote in message ... No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. There are only a few that use electronic viewfinders and they are low end. Correct. I have two DSLRs, (Canon EOS 10D, & EOS 1Dmk2), & they both use optical viewfinders. I certainly wouldn't waste my money on DSLRs with electronic viewfinders. -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- |
#14
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
Arfa Daily wrote:
"dennis@home" wrote in message ... "Arfa Daily" wrote in message ... No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. There are only a few that use electronic viewfinders and they are low end. I'm pretty sure that one of them told me that his camera was over a grand's worth, so I wouldn't call that particularly low end, Are you kidding? My EOS 1Dmk2 cost $7000AUD. A grand is nothing for a decent DSLR. although I am sure there are others more expensive. If they do not have an LCD panel on them to at least review the pictures you have taken, without having to plug the thing into a computer, that rather defeats the object of it being a portable 'digital' camera, doesn't it ? Sure, but the LCD is to review the shot after you've taken it. You use the optical viewfinder when you're taking your shot. Perhaps I am not being quite accurate in calling it a "viewfinder". I accept that the higher end cameras have a proper optical viewfinder operating on the SLR mirror / prism system, Correct. but the LCD panel also serves as a supplementary viewfinder, as well as a display medium for photos already taken. Well, on some newer models you have a feature called "Live View", where you can use the LCD to focus, etc, but no serious photographer would use that in preference to the traditional viewfinder. OTOH, the LCD is really handy to ensure that the shot turned out the way that you wanted it to. -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- |
#15
Posted to sci.electronics.repair,uk.d-i-y
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Bit of a con, really ... ?
In article ,
William Sommerwerck wrote: Quite a bit of what I'm saying comes from working in TV production - although I'm on the sound side. But hear plenty from those who work on the vision side of things. ;-) And it was certainly the case that Grade 1 picture monitors continued with delta gun tubes long after PIL were introduced domestically -- and stuck with the original NTSC phosphors. As this was the standard the cameras were 'calibrated' to. But there was no "original" NTSC red phosphor -- just a standard for it, that the original red phosphors didn't meet. The phosphors as used when colour TV arrived in the UK were known as NTSC standard by the BBC. And were still specified for Grade 1 monitors for many years afterwards. Indeed probably still are. -- *Verbs HAS to agree with their subjects * Dave Plowman London SW To e-mail, change noise into sound. |
#16
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Bit of a con, really ... ?
In article ,
Bob Larter wrote: Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. There are only a few that use electronic viewfinders and they are low end. Correct. I have two DSLRs, (Canon EOS 10D, & EOS 1Dmk2), & they both use optical viewfinders. I certainly wouldn't waste my money on DSLRs with electronic viewfinders. Don't they have an LCD screen for viewing purposes, though? Not that you can judge the variety of tones that make up a face on something so small. -- *Even a blind pig stumbles across an acorn now and again * Dave Plowman London SW To e-mail, change noise into sound. |
#17
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Bit of a con, really ... ?
I have two DSLRs, (Canon EOS 10D, & EOS 1Dmk2), & they both use
optical viewfinders. I certainly wouldn't waste my money on DSLRs with [only] electronic viewfinders. Are there any? Nearly 40 years ago, I imagined a film-based SLR with an electronic viewfinder that showed how the final image would look, depending on the film you used, and (with B&W materials) the way you developed and printed. |
#18
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Bit of a con, really ... ?
Well, on some newer models you have a feature called "Live View",
where you can use the LCD to focus, etc, but no serious photographer would use that in preference to the traditional viewfinder. As I pointed out earlier, the LCD is a great way to fine-tune the color balance in real time. |
#19
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Bit of a con, really ... ?
Quite a bit of what I'm saying comes from working in TV production -
although I'm on the sound side. But hear plenty from those who work on the vision side of things. ;-) And it was certainly the case that Grade 1 picture monitors continued with delta gun tubes long after PIL was introduced domestically -- and stuck with the original NTSC phosphors. As this was the standard the cameras were 'calibrated' to. But there was no "original" NTSC red phosphor -- just a standard for it, that the original red phosphors didn't meet. The phosphors as used when colour TV arrived in the UK were known as NTSC standard by the BBC. And were still specified for Grade 1 monitors for many years afterwards. Indeed, probably still are. Forgive me, but how something is spec'd does not mean that the real-world implementation -- regardless of its name -- meets the spec. Of course, color TV was so late arriving in GB, it's likely that only the improved red phosphors were used. |
#20
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Bit of a con, really ... ?
On Thu, 14 May 2009 00:21:51 +1000 Bob Larter
wrote in Message id: : Are you kidding? My EOS 1Dmk2 cost $7000AUD. A grand is nothing for a decent DSLR. For that kind of money, it better perform like those X-ray glasses you used to be able to buy in the back of comic books! |
#21
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Bit of a con, really ... ?
The value of an additional LCD view depends entirely on the sort of
photographic work you're doing. For close-up shots of complicated, highly reflective objects a live view facility with pinpoint focussing is a real boon - as is the ability to see the image in real time on a computer screen. It allows for some very specialised techniques, such as manipulating the depth-of-field by the millimetre. In fact because of the limitations of DSLR live view at the current time I'd say it was more of a function of use to the studio professional than the amateur. The Canon 5D II (and possibly other cameras) lets you connect to an HD display so you can get an even bigger live view. I haven't tried this yet. |
#22
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Bit of a con, really ... ?
On Thu, 14 May 2009 00:21:51 +1000, Bob Larter
wrote: snip Well, on some newer models you have a feature called "Live View", where you can use the LCD to focus, etc, but no serious photographer would use that in preference to the traditional viewfinder. OTOH, the LCD is really handy to ensure that the shot turned out the way that you wanted it to. The value of an additional LCD view depends entirely on the sort of photographic work you're doing. For close-up shots of complicated, highly reflective objects a live view facility with pinpoint focussing is a real boon - as is the ability to see the image in real time on a computer screen. It allows for some very specialised techniques, such as manipulating the depth-of-field by the millimetre. In fact because of the limitations of DSLR live view at the current time I'd say it was more of a function of use to the studio professional than the amateur. Regards, -- Steve ( out in the sticks ) Email: Take time to reply: timefrom_usenet{at}gmx.net |
#23
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Bit of a con, really ... ?
On Wed, 13 May 2009 07:37:12 -0700, "William Sommerwerck"
wrote: I have two DSLRs, (Canon EOS 10D, & EOS 1Dmk2), & they both use optical viewfinders. I certainly wouldn't waste my money on DSLRs with [only] electronic viewfinders. Are there any? I looked at a Sony ( I think ) one last year with a particular project in mind. There were only two things I remember about it - the LCD view screen flipped out and could be angled, which was handy - and the image in the viewfinder was bloody awful. I bought a Canon. Regards, -- Steve ( out in the sticks ) Email: Take time to reply: timefrom_usenet{at}gmx.net |
#24
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Bit of a con, really ... ?
On Wed, 13 May 2009 08:39:30 -0700, "William Sommerwerck"
wrote: The value of an additional LCD view depends entirely on the sort of photographic work you're doing. For close-up shots of complicated, highly reflective objects a live view facility with pinpoint focussing is a real boon - as is the ability to see the image in real time on a computer screen. It allows for some very specialised techniques, such as manipulating the depth-of-field by the millimetre. In fact because of the limitations of DSLR live view at the current time I'd say it was more of a function of use to the studio professional than the amateur. The Canon 5D II (and possibly other cameras) lets you connect to an HD display so you can get an even bigger live view. I haven't tried this yet. I think the new 500D and 50D models have this feature too, and it's something I've got my eye on. I had a look at the specs of the new 5D a while back and I'm sorely tempted... Regards, -- Steve ( out in the sticks ) Email: Take time to reply: timefrom_usenet{at}gmx.net |
#25
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Bit of a con, really ... ?
In article ,
William Sommerwerck wrote: The phosphors as used when colour TV arrived in the UK were known as NTSC standard by the BBC. And were still specified for Grade 1 monitors for many years afterwards. Indeed, probably still are. Forgive me, but how something is spec'd does not mean that the real-world implementation -- regardless of its name -- meets the spec. Of course, color TV was so late arriving in GB, it's likely that only the improved red phosphors were used. Finally the penny's dropped. -- *If PROGRESS is for advancement, what does that make CONGRESS mean? Dave Plowman London SW To e-mail, change noise into sound. |
#26
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Bit of a con, really ... ?
"William Sommerwerck" wrote in message ... Well, on some newer models you have a feature called "Live View", where you can use the LCD to focus, etc, but no serious photographer would use that in preference to the traditional viewfinder. As I pointed out earlier, the LCD is a great way to fine-tune the color balance in real time. Just shoot in RAW. The colour balance is just a filter applied post shot to the RAW data. You can then adjust it to whatever you want in the viewing conditions you want when you "develop" your pictures. |
#27
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Bit of a con, really ... ?
"Stephen Howard" wrote in message ... On Thu, 14 May 2009 00:21:51 +1000, Bob Larter wrote: snip Well, on some newer models you have a feature called "Live View", where you can use the LCD to focus, etc, but no serious photographer would use that in preference to the traditional viewfinder. OTOH, the LCD is really handy to ensure that the shot turned out the way that you wanted it to. The value of an additional LCD view depends entirely on the sort of photographic work you're doing. For close-up shots of complicated, highly reflective objects a live view facility with pinpoint focussing is a real boon - as is the ability to see the image in real time on a computer screen. It allows for some very specialised techniques, such as manipulating the depth-of-field by the millimetre. In fact because of the limitations of DSLR live view at the current time I'd say it was more of a function of use to the studio professional than the amateur. I have done a few product shots before and the best way to work in the studio is a laptop and a data cable to the camera. I find the LCD is virtually redundant for static studio work. More important is a high speed data link, USB is very slow. |
#28
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Bit of a con, really ... ?
As I pointed out earlier, the LCD is a great way to fine-tune the color
balance in real time. Just shoot in RAW. The colour balance is just a filter applied post shot to the RAW data. You can then adjust it to whatever you want in the viewing conditions you want when you "develop" your pictures. True, but what if you want or need to use the JPG immediately? |
#29
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Bit of a con, really ... ?
"William Sommerwerck" wrote in message ... As I pointed out earlier, the LCD is a great way to fine-tune the color balance in real time. Just shoot in RAW. The colour balance is just a filter applied post shot to the RAW data. You can then adjust it to whatever you want in the viewing conditions you want when you "develop" your pictures. True, but what if you want or need to use the JPG immediately? Virtually all cameras that shoot in RAW can also do jpegs simultaneously. Some (most?) also allow you to "develop" in the camera |
#30
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Bit of a con, really ... ?
In article , William Sommerwerck wrote:
I have two DSLRs, (Canon EOS 10D, & EOS 1Dmk2), & they both use optical viewfinders. I certainly wouldn't waste my money on DSLRs with [only] electronic viewfinders. Are there any? By definition, no. There's the Panasonic Lumix G1, which is basically a DSLR with no mirror, pentaprism, or viewfinder, but that makes it not actually an SLR. http://www.dpreview.com/reviews/panasonicdmcg1/ But the original claim was that there are few SLRs using electronic viewfinders and they were all low end. In fact live view is becoming more common, and the Canon EOS 5D Mark II, while not at the very top end, is hardly low end either. |
#31
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Bit of a con, really ... ?
"Bob Larter" wrote in message ... Arfa Daily wrote: We had some pretty fussy customers back then with serious pots of money, and I can't recall any colour accuracy issues ever arising - aside from one particular customer who used to complain on a weekly basis that colours were "bleeding through" (convergence issues !) and in the summer that there was something wrong because the grass in front of the wicket on the cricket, was yellow ... LOL. It didn't occur to him that well trampled grass, in summer, is often yellow? -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- It was actually Mrs Fussy that always called us. Mr Fussy was an inoffensive little thing who sat quietly up the corner ... No amount of explanation would ever convince her that sometimes, grass *is* yellow. There was only ever one engineer that she would have work on her set as well. I was his apprentice, so I got to call on her with him. I clearly remember on one occasion when my mentor was on holiday, the boss decided to send me on a call to her, figuring that it would be ok, as she already knew me, and knew that I was Peter's apprentice. When I turned up at her house, she wouldn't even let me in the door. She told me that she was sure that I was very good, but that I was not Peter, and he was the only one capable of adjusting her TV just the way she liked it. The really amusing thing was that Peter never really actually did anything other than take the back off and make twiddling motions with his arms, and then ask her if it now looked better. Putting up a test card showing a perfectly adjusted picture was also a no-no. She would just trill "I don't care if you think that that silly picture looks right or not. We don't sit here watching a test card, do we ?" On one occasion when there was a real fault, and a replacement component had to be soldered in, she marched into the room and said "Peter ! I do hope that you're not smoking behind my television !" There are endless stories of encounters with this customer, whom I swear was a real person,and who behaved exactly as described. Ah, happier and gentler times ... Arfa |
#32
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Bit of a con, really ... ?
"William Sommerwerck" wrote in message ... "Dave Plowman (News)" wrote in message ... In article , Arfa Daily wrote: Contrary to what you believe about the phosphors on CRTs, I don't believe that there has been any significant change in their colour rendition capabilities since the earliest delta gun tubes in the uk, which I worked with from about 1970 Oh, but there was. The original delta gun shadow mask tubes used the correct NTSC phosphors. Which gave a pretty pure red. The rot really came in with PIL tubes which used a very 'orange' red phosphor simply because it allowed a brighter picture. And that had real implications to flesh tones. Took many years before that was corrected. I would almost bet my life that this is absolutely backwards -- it was the original phosphors that were orangish, improving only with the rare-earth phosphors of the early '60s. (I remember Sylvania's radio ads.) In fact, I'm pretty certain that most of what's being posted about color TV and color analysis/reproduction is utter bilge. But I don't have a comprehensive understanding of this material (it's not easy), so I'm pretty much keeping my mouth shut. What I said about non-spectral colours, and the inability of a tri colour CRT to genuinely reproduce them, is not bilge though - see the link that I posted earlier in the thread, refering to this. Arfa |
#33
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Bit of a con, really ... ?
Man at B&Q wrote:
On May 13, 12:31 pm, "dennis@home" wrote: "Arfa Daily" wrote in message ... No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. And your posts use smoke and mirrors. In this case strangely rarely and uniquely, Dennis is correct. My SLR has no electronics in the viewfinder. Its all done with mirrors. |
#34
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Bit of a con, really ... ?
Dave Plowman (News) wrote:
In article , Bob Larter wrote: Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. There are only a few that use electronic viewfinders and they are low end. Correct. I have two DSLRs, (Canon EOS 10D, & EOS 1Dmk2), & they both use optical viewfinders. I certainly wouldn't waste my money on DSLRs with electronic viewfinders. Don't they have an LCD screen for viewing purposes, though? Not that you can judge the variety of tones that make up a face on something so small. Not really, no. The LCD on mine is for menu items and occasionally a quick postview of shots already taken., |
#35
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Bit of a con, really ... ?
Arfa Daily wrote:
"dennis@home" wrote in message ... "Arfa Daily" wrote in message ... No, I wasn't either. I have two friends who both own top end digital SLRs, one because he is a professional photographer, and the other because he is a very keen hobbyist. I have looked at the viewfinder images closely on both of these cameras, and the rendition of flesh tones in all the varieties is excellent, and the professional of the two has commented to me how good he thinks the viewfinder is at colour rendition under all light levels (input that is, not viewing conditions). Top level digital SLRs don't use any electronics in the viewfinder, its all done with mirrors. There are only a few that use electronic viewfinders and they are low end. I'm pretty sure that one of them told me that his camera was over a grand's worth, so I wouldn't call that particularly low end, although I am sure there are others more expensive. If they do not have an LCD panel on them to at least review the pictures you have taken, without having to plug the thing into a computer, that rather defeats the object of it being a portable 'digital' camera, doesn't it ? Even the 3 grand offering on this page has a 3" LCD http://www.calumetphoto.co.uk/Digita...utm_medium=cpc Perhaps I am not being quite accurate in calling it a "viewfinder". I accept that the higher end cameras have a proper optical viewfinder operating on the SLR mirror / prism system, but the LCD panel also serves as a supplementary viewfinder, as well as a display medium for photos already taken. It does not and cannot, because there is a ****ing great mirror between the lens and the CCD as well as a closed shutter. OK? Arfa |
#36
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Bit of a con, really ... ?
William Sommerwerck wrote:
Well, on some newer models you have a feature called "Live View", where you can use the LCD to focus, etc, but no serious photographer would use that in preference to the traditional viewfinder. As I pointed out earlier, the LCD is a great way to fine-tune the color balance in real time. Why bother? That's all doable post the event in photoshop. What you DO need is a histogram display to show you haven't saturated any of the channels. That you cant 'shop out. I shoot entirely without more than a quick color temp adjustment, and often not that. If I want a crisper image for a product shot, I can do all that in software. |
#37
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Bit of a con, really ... ?
William Sommerwerck wrote:
As I pointed out earlier, the LCD is a great way to fine-tune the color balance in real time. Just shoot in RAW. The colour balance is just a filter applied post shot to the RAW data. You can then adjust it to whatever you want in the viewing conditions you want when you "develop" your pictures. True, but what if you want or need to use the JPG immediately? Then you need a video camera ;-) |
#38
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Bit of a con, really ... ?
Stephen Howard wrote:
On Thu, 14 May 2009 00:21:51 +1000, Bob Larter wrote: snip Well, on some newer models you have a feature called "Live View", where you can use the LCD to focus, etc, but no serious photographer would use that in preference to the traditional viewfinder. OTOH, the LCD is really handy to ensure that the shot turned out the way that you wanted it to. The value of an additional LCD view depends entirely on the sort of photographic work you're doing. For close-up shots of complicated, highly reflective objects a live view facility with pinpoint focussing is a real boon - as is the ability to see the image in real time on a computer screen. It allows for some very specialised techniques, such as manipulating the depth-of-field by the millimetre. You dont have a depth of field preview on the camera? In fact because of the limitations of DSLR live view at the current time I'd say it was more of a function of use to the studio professional than the amateur. I wouldn't even say that. Regards, |
#39
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Bit of a con, really ... ?
In article ,
The Natural Philosopher wrote: Don't they have an LCD screen for viewing purposes, though? Not that you can judge the variety of tones that make up a face on something so small. Not really, no. The LCD on mine is for menu items and occasionally a quick postview of shots already taken., That's what I mean. No point in having a digital camera if you can't look at a pic instantly. Might as well stick to film. -- *Everyone has a photographic memory. Some just don't have film* Dave Plowman London SW To e-mail, change noise into sound. |
#40
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Bit of a con, really ... ?
Dave Plowman (News) wrote:
In article , The Natural Philosopher wrote: Don't they have an LCD screen for viewing purposes, though? Not that you can judge the variety of tones that make up a face on something so small. Not really, no. The LCD on mine is for menu items and occasionally a quick postview of shots already taken., That's what I mean. No point in having a digital camera if you can't look at a pic instantly. Might as well stick to film. Well I shot 150 pics on Sunday and ddi'nt look at a single one till Sunday night. What's the point? they were action shots. They either worked or they didn't. About 10% were usable. |
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