here tv screenshot (1.3m base) in the 80 lumen setting
5pm cloudy day all windows open
5pm cloudy day all windows open
An externally hosted image should be here but it was not working when we last tested it.
the previuos picture is bright enough but some of th snapshot are not so brigh.
concerning the contrast, I'm sorry rox but measurements on a smaller image with higher lux outpu didn't change the final contrast value . It's around 80-100 for 1. even with white at 400 lux the black value is around 4-5 lux.
concerning the contrast, I'm sorry rox but measurements on a smaller image with higher lux outpu didn't change the final contrast value . It's around 80-100 for 1. even with white at 400 lux the black value is around 4-5 lux.
you didn´t understand me.
first of all let me ask some questions;
is your luxmeter 0.1 lux the minimun resolution? (how mny digits?)
do you know the stated accuracy?
I am not sugesting you to meassure the smaller imagesize projection. I was sugesting you to meassure same imagesize but place the luxmeter just at the projection lens (close or in contact). This way the lux meassuremnt will be much higher (i believe somehere 4000 lux for white) and the black meassuremt will be increased as well somewhere 50-100 lux i belieeve). Those measurements i believe to be more TRUER on the luxmeter than the low 0.5 lux measuremt you had.
Some digital tool acuracy is stated as 3% + 2 digit max error for instance. This means that 0.5 (000.5 displayed?) is stated to be inside 0.285 and 0.715 lux range. This result in 178:1 to 71:1 contrast range posible.
The meassuremt on the projection lens though, is less dependent to the 2 digit error acuracy, so is more beliebable. Do you undertand why am I asking you to meassure on the triplet output?
first of all let me ask some questions;
is your luxmeter 0.1 lux the minimun resolution? (how mny digits?)
do you know the stated accuracy?
I am not sugesting you to meassure the smaller imagesize projection. I was sugesting you to meassure same imagesize but place the luxmeter just at the projection lens (close or in contact). This way the lux meassuremnt will be much higher (i believe somehere 4000 lux for white) and the black meassuremt will be increased as well somewhere 50-100 lux i belieeve). Those measurements i believe to be more TRUER on the luxmeter than the low 0.5 lux measuremt you had.
Some digital tool acuracy is stated as 3% + 2 digit max error for instance. This means that 0.5 (000.5 displayed?) is stated to be inside 0.285 and 0.715 lux range. This result in 178:1 to 71:1 contrast range posible.
The meassuremt on the projection lens though, is less dependent to the 2 digit error acuracy, so is more beliebable. Do you undertand why am I asking you to meassure on the triplet output?
yes it has 3% + 2 digit accuracy and 0.01 resolution.
About your measurement, yes I measure the image close to the lens but on the ansi black and white picture. So the measurement has been done like at 1m of the lens (explaining the 400lux) in order to have a black and white area large enough for the luxmeter measurement.
Ok I'll do next time close to the lens on a totally white or totally black picture.
In fact I already did this on white picture and the value was around 10000lux.
Concerning the S.D. of my measurement on the ansi picture, I agree that it could be between 1:71 to 1:178. But 1:178 is low contrast too
Ok i'll do more measurement at higher lux value to confirm this.
In fact I'll like to know if the initial contrast stated for one lcd (considering equal light power) not stipped could be a good indicator of what we get in our VP.
i think the working conditions of the lcd does change the stated contrast. (I think it will be improved) since we are using collimated light only.
The 0.01 lux is your luxmeter resolution????? you can meassure 0.03, or 0.09 , 4.59, 1.12 ... lux values on your luxmeter?
i can´t meassure less than 1 lux. (1 lux is the resolution on my luxmeter)
Please check that info for me. I would say you don´t have such good luxmeter 😀
The 0.01 lux is your luxmeter resolution????? you can meassure 0.03, or 0.09 , 4.59, 1.12 ... lux values on your luxmeter?
i can´t meassure less than 1 lux. (1 lux is the resolution on my luxmeter)
Please check that info for me. I would say you don´t have such good luxmeter 😀
Well so time you are right and some time wrong 😉
yes , in fact this is even better 😀
the brand is vorkraft digital luxmeter MS-1500
metering range accuracy resolution
0 to 40000 lx ± 3% ± 5 digits 0,01 lx to 10 lx
0 to 4000 fc ± 3% ± 5 digits 0,001 fc to 1 fc
50Euros with a 30% discount on conrad.fr
you have the technical pdf in german and english on their web site.
yes , in fact this is even better 😀
the brand is vorkraft digital luxmeter MS-1500
metering range accuracy resolution
0 to 40000 lx ± 3% ± 5 digits 0,01 lx to 10 lx
0 to 4000 fc ± 3% ± 5 digits 0,001 fc to 1 fc
50Euros with a 30% discount on conrad.fr
you have the technical pdf in german and english on their web site.
i don´t understand your luxmeter specs.
let me show you how is mine;
The display is 18888 (5 digits but the first one is only able to display 0 or 1). So it displays from 0 to 19999 value.
There is 2 ranges (autoswich);
0-19999 (20 Klx)
0-100000 (100 Klx) when this range is autoswiched, there is a X10 pilot on the lcd as well, so 10 lux resolution is DISPLAYED. (any value under 10 lux just can´t be displayed, so i can´t say if there is 58970 lux or 58979 lux or any value between this range, because i can´t see more than 10 lux resolution on the display (5897 and X10 is displayed).
the low range, is 1 lux resolution so I can´t see neither 0.X lux values. So my luxmeter smallest resolution is 1 lux.
Please tell me what is your luxmeter displayed value as clear as i did post.
let me show you how is mine;
The display is 18888 (5 digits but the first one is only able to display 0 or 1). So it displays from 0 to 19999 value.
There is 2 ranges (autoswich);
0-19999 (20 Klx)
0-100000 (100 Klx) when this range is autoswiched, there is a X10 pilot on the lcd as well, so 10 lux resolution is DISPLAYED. (any value under 10 lux just can´t be displayed, so i can´t say if there is 58970 lux or 58979 lux or any value between this range, because i can´t see more than 10 lux resolution on the display (5897 and X10 is displayed).
the low range, is 1 lux resolution so I can´t see neither 0.X lux values. So my luxmeter smallest resolution is 1 lux.
Please tell me what is your luxmeter displayed value as clear as i did post.
mmm tell me you are not a believer aren't you 🙂
ok there is different scale
like 0-40
0-400
0-4000
up to 0-40000.
and the resolution is 0.01
then when you measure in the 0-40 scale the data is something like 5.02
if you measure between 0-400 you might have 392.66
etc... 5 digit on the screen max or less depending on the scale.
ok there is different scale
like 0-40
0-400
0-4000
up to 0-40000.
and the resolution is 0.01
then when you measure in the 0-40 scale the data is something like 5.02
if you measure between 0-400 you might have 392.66
etc... 5 digit on the screen max or less depending on the scale.
😀, i understand now.
thanks for the info. Now let me see what math I can do with the stated accuracy and the displayed value to see the contrast range...
mm i will asume the black measuremnt you did was displaying 0.50 value on the display...
so 3% + 5 digit error does mean that 0.435 to 0.565 range of error is stated. (the real value, the one god knows 😀, is somewhere inside this stated range).
so the 51 lux value, again in the stated range of 44.47 to 57.53 lux range.
Now the worst contrast posible is 44.47/0.565==> 79:1
and the best contrast posible is 57.53/0.435==> 132:1
anyway, I sugest you to meassure close to the lens the two values. I would say the values displayed on the luxmeter are much closer to the ones God knows 😀. (I would say the near 0 values on the luxmeter are much more desviated)
just let me know if you take the meassurments ok? see you.
thanks for the info. Now let me see what math I can do with the stated accuracy and the displayed value to see the contrast range...
mm i will asume the black measuremnt you did was displaying 0.50 value on the display...
so 3% + 5 digit error does mean that 0.435 to 0.565 range of error is stated. (the real value, the one god knows 😀, is somewhere inside this stated range).
so the 51 lux value, again in the stated range of 44.47 to 57.53 lux range.
Now the worst contrast posible is 44.47/0.565==> 79:1
and the best contrast posible is 57.53/0.435==> 132:1
anyway, I sugest you to meassure close to the lens the two values. I would say the values displayed on the luxmeter are much closer to the ones God knows 😀. (I would say the near 0 values on the luxmeter are much more desviated)
just let me know if you take the meassurments ok? see you.
ok I did the measurements, it was not too difficult😎
then lux output at the projection lens
white 9500
black 75
contrast 126.6666666666667 for 1😀
God knows the real contrast value but for me this value is around 1:100 so very low...
however with such a good luxmeter the value on the ansi picture was not so nderestimated.
Now the big question is as I got a brightness good enough for me, HOW to improve the contrast of my system????
then lux output at the projection lens
white 9500
black 75
contrast 126.6666666666667 for 1😀
God knows the real contrast value but for me this value is around 1:100 so very low...
however with such a good luxmeter the value on the ansi picture was not so nderestimated.
Now the big question is as I got a brightness good enough for me, HOW to improve the contrast of my system????
yes, i understimated your luxmeter 😀. (this trick of measuring in the projection lens, is the only way i have to meassure the contrast with my luxmeter)
The image looks very good anyway. The stated contrast for the lilli is 200:1 isn´t it?
mmm, have you "played" with the brightness/contrast values to get the "best" performances when the meassuremnt was done or you just have the setup as you like to have and only measured the values?
I mean, when manufacturers state the specs, i believe the image quality is the last thing they care about. They only setup it so the best spec is achieved. I prefer a custom setup meassuremnt though, because it is at the end what we are going to be waching to.
about how can you improve the contrast.... some interesting research is being done about removing the antiglare from the lcd... it is soon yet, but it looks like eveything gets better 😀.
The image looks very good anyway. The stated contrast for the lilli is 200:1 isn´t it?
mmm, have you "played" with the brightness/contrast values to get the "best" performances when the meassuremnt was done or you just have the setup as you like to have and only measured the values?
I mean, when manufacturers state the specs, i believe the image quality is the last thing they care about. They only setup it so the best spec is achieved. I prefer a custom setup meassuremnt though, because it is at the end what we are going to be waching to.
about how can you improve the contrast.... some interesting research is being done about removing the antiglare from the lcd... it is soon yet, but it looks like eveything gets better 😀.
you are righ, i completly forgot the setting in the osd.
so brightness at 0 and contrast 100 give the better contrast value
white 6000 black 25 thus 240:1 lens measurement
white 38 black 0.38 thus 100:1 screen measurement
So the linearity for low lux measurement is certainly not perfect on that luxmeter too.
So the min max lux value on white vary from 6000 to 9500 at the lens
and min max value on back vary from 25 to 75 at the lens.
giving contrast from 127: to 240: through osd measurement.
In fact I realize that i put the brightness to high in my setting.
So you think that we should get higher value of contrast in our pj than what is stated for the original lcd!
Could you inform me about the antiglare??? what is it?
so brightness at 0 and contrast 100 give the better contrast value
white 6000 black 25 thus 240:1 lens measurement
white 38 black 0.38 thus 100:1 screen measurement
So the linearity for low lux measurement is certainly not perfect on that luxmeter too.
So the min max lux value on white vary from 6000 to 9500 at the lens
and min max value on back vary from 25 to 75 at the lens.
giving contrast from 127: to 240: through osd measurement.
In fact I realize that i put the brightness to high in my setting.
So you think that we should get higher value of contrast in our pj than what is stated for the original lcd!
Could you inform me about the antiglare??? what is it?
nice info.
mmm, yes, the collimated light trhow the lcd (paralell) "could" improve the stated contrast value. The contrast drops with the angle, so the stated contrast value for the lcd was somehow afected by the sides of the lcd. Now this is not happening since there is only paralell light trhow the lcd. This could improve the contrast 😀.
The antiglare is a surface tratement lcd manufacturers do. It does two things;
The light from the viewers side (a lamp behind you) will hit the lcd and will be reflected by the front glass. This image reflection is anoying, we don´t want to see the reflecton but the image on the lcd. So the reflection is difused because of the antiglare. It is still reflected but not as perfect as a mirror would do. The reflected light is spread in a wider angle so less light is going to your eyes. This is how virtually the teflection disapears (is less noticeable in fact)
and the second effect if that this difusive effect is as well difusing the light coming from the lcd. This does increase the viewing angle of the lcd. We don´t like it becouse we want very narrow vision on the lcd; only light going to the projection lens.
The antiglare layer does make harded to focus the light arc on the projection lens. The size of the light point is inevitably bigger because of this layer.
Some people is removing this layer from the lcd but it is very brave modification 😀. I don´t feel brave enough to do it yet. But am keeping an eye to those people sperimenting with it.
mmm, yes, the collimated light trhow the lcd (paralell) "could" improve the stated contrast value. The contrast drops with the angle, so the stated contrast value for the lcd was somehow afected by the sides of the lcd. Now this is not happening since there is only paralell light trhow the lcd. This could improve the contrast 😀.
The antiglare is a surface tratement lcd manufacturers do. It does two things;
The light from the viewers side (a lamp behind you) will hit the lcd and will be reflected by the front glass. This image reflection is anoying, we don´t want to see the reflecton but the image on the lcd. So the reflection is difused because of the antiglare. It is still reflected but not as perfect as a mirror would do. The reflected light is spread in a wider angle so less light is going to your eyes. This is how virtually the teflection disapears (is less noticeable in fact)
and the second effect if that this difusive effect is as well difusing the light coming from the lcd. This does increase the viewing angle of the lcd. We don´t like it becouse we want very narrow vision on the lcd; only light going to the projection lens.
The antiglare layer does make harded to focus the light arc on the projection lens. The size of the light point is inevitably bigger because of this layer.
Some people is removing this layer from the lcd but it is very brave modification 😀. I don´t feel brave enough to do it yet. But am keeping an eye to those people sperimenting with it.
well I have a broken lilli lcd, so may be I can do some try on this one. You say this is a filter from the outer side to remove.
since the lcd is broken i can just look the effect of this modification on brigtness but not on contrast. not very usefull then
since the lcd is broken i can just look the effect of this modification on brigtness but not on contrast. not very usefull then
mmm, hold on.
To remove the antiglare film, it needs to have the antiglare film 😀
i don´t know if the lilli has the antiglare. The antiglare is attached to the front polarizer. So you have to remove both things. Then you need a new polarizer (with no antiglare on it).
maybe the lilli has not the antiglare (i would say not since its fiedl of view isn´t very good...) but cant say is sure.
some are removing the front polarizer+antiglare and placing a photographic polarizer in the projection lens. (those filters are very good) If you don´t use the polarizer, you can´t see nothing. Well, on the broken lilli you can´t see nothing anyway...
To remove the antiglare film, it needs to have the antiglare film 😀
i don´t know if the lilli has the antiglare. The antiglare is attached to the front polarizer. So you have to remove both things. Then you need a new polarizer (with no antiglare on it).
maybe the lilli has not the antiglare (i would say not since its fiedl of view isn´t very good...) but cant say is sure.
some are removing the front polarizer+antiglare and placing a photographic polarizer in the projection lens. (those filters are very good) If you don´t use the polarizer, you can´t see nothing. Well, on the broken lilli you can´t see nothing anyway...
so i just can see if there is one or two film on the outer face. if there is 2 this is that there is an antiglare on the lilli. we'll just have that info.
mmm, i wouln't say that.
the antiglare is a surface treatement done to the polarizer film. there is only 1 film. you can´t just remove the antiglare (it isn´t that easy 😀)
but actually i don´t know much about it. I just know 3 people did it.
the antiglare is a surface treatement done to the polarizer film. there is only 1 film. you can´t just remove the antiglare (it isn´t that easy 😀)
but actually i don´t know much about it. I just know 3 people did it.
you mean 3 people succeed in removing the antiglare and got a better contrast
or you mean just 3 people try to do it🙂
or you mean just 3 people try to do it🙂
😀:😀😀
good question 😀.
3 people is experimenting with it right now. This antiglare remove is new concept for them as well (this week has been posted first time 😀)
they have removed the film and have projected images with diferent polarizers... They say it improves a lot.
there has been some preliminar test to the antiglare remove step. The easiest was that a tape on the screen (yes, the trasparent tape we use for whatever) you can paste it on the 15 or 17" screen and look at it. It is geneally acepted that it improves brightness 😀. (absurd? i sugest you to test it 😀).
one of them said the brightness and the contrast both improved alot. He doesn´t have a luxmeter so hasn´t documented values but his sensation was contundent; It improves image quality.
good question 😀.
3 people is experimenting with it right now. This antiglare remove is new concept for them as well (this week has been posted first time 😀)
they have removed the film and have projected images with diferent polarizers... They say it improves a lot.
there has been some preliminar test to the antiglare remove step. The easiest was that a tape on the screen (yes, the trasparent tape we use for whatever) you can paste it on the 15 or 17" screen and look at it. It is geneally acepted that it improves brightness 😀. (absurd? i sugest you to test it 😀).
one of them said the brightness and the contrast both improved alot. He doesn´t have a luxmeter so hasn´t documented values but his sensation was contundent; It improves image quality.
so if i put some tape on my dead lilli i should increase from 5% transmissivity to a higher value?
let's try.
let's try
however I'm usually more convinced by some consistent measurments then by feeling and sensation. I won't bet my working lilli on that improvement.
let's try.
let's try
however I'm usually more convinced by some consistent measurments then by feeling and sensation. I won't bet my working lilli on that improvement.
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