DIY Video Projector Part II

You are complaining without giving a valid reason why it shouldn't be done

ace3000_1 said:
and what about the brightness of your monitor? your monitor might be brighter than mine and might have a different contrast setting too, wana callobrate them as well?

Like i explained when first posting this suggestion, A description of external lighting conditions ALONG with a scale of how much brighter/darker the posted pic is from reality should be enough for an understanding of the posted pic. Like i already said in a previous post, once i have this information, i can adjust the brightness on my screen (and everybody can adjust the brightness on their own screens) to what looks to me to be equivalent to the external lghting conditions described, and then be able to say "The actual result is *approximately* so-and-so-scale brighter/darker than the posted pic.

Ok...i think i understand your point now...Then the scale is not necessary, but a standard way to describe external lighting condition should be sufficient and necessary.

You may be arguing, ace3000, that it's not possible, but i disagree and i think a good discussion could yield a good standard.


proto5 said:
Property:
Give it up. It's not gonna happen.
Just start building a projector using the info already here. All this formula and weird water cooling crap does nothing but alienate us "more experienced" DIY's in here. And quit posting so much, cause we really don't give a crap about 99% of your posts so far....and you don't want to get booted.....

This was not a necessary post. And contributes nothing in as much as a way to understand posted Pics is STILL NECESSARY. Instead of complaining Proto5, I suggest you come up with a way for everybody to be able to understand Posted Pics.

You two are getting too excited at an opportunity to debase others.

The fact is that YOU may not care about being able to decipher posted pics (especially you Proto5)....

But a little forethought into the fact that this Projector Forum may go on FOR YEARS and into possibly TENS OF THOUSANDS of posts (as it has been doing), and may advance into BETTER TECHNOLOGY as better technology comes around and gets CHEAPER and MORE AVAILABLE, suggests that an agreed upon standard for understanding and posting results is a

**WORTHWHILE TOPIC TO DISCUSS.**


are you arguing that it's not? Then say so (Proto5), and give good reasons why not, instead of resorting to threats and insults.
 
whatever

Prop-
Like Ace said, it's not do-able. But you cant seem to give up! Believe it or not you are not always in the right. People like that really tend to grate on ones nerves....
Us more experienced BUILDERS see a newbie come in and start spouting all of these weird bizarro posts and ideas and sorry, but I for one am sick of listening. why not quit posting till you have something to show, like most of us did.

This is Proto5's last post to do anything with property- at least till he puts his $$$ where his mouth is and posts photos of his fish-tank cooled 10 million lumen blow your socks off projector that he never really intends to build. I'll be the first to eat crow if it ever happens.
 
Re: Property

zardoz said:

I understand what it is you are trying to do..but without establishing a "baseline" that can be applied from one setup to another your results will be "skewed".

Baseline is the sun, and should be adequate. Remember, i'm asking for a standard way to describe external lighting conditions... If you say it's 4pm mid afternoon with blinds full open, I can adjust my screen to look like 4pm blinds full open. Sure this system is not perfect. But there is room for refinement. For instance angle of the sun in relation to the room ("the sun is streaming in through the 4'x3' window on the left at an angle of 45degrees"--- we need a way to encode this)... Whatever the method...I'm sure we can come up with an acceptable way to do it, couldn't we?


Even if a baseline could be established there are still too many variables...screen gain...lamp source...signal source....on and on... You would need to say ok with a model#XXX movie screen @ X number of feet from the PJ...with bulb X...and panel X....and signal X...resollution X....even after all of this is established you are relying on the "eye of the beholder" to be the final factor.

These are all variables which can be ANALYZED AFTER interest in the posted pic is shown. In Fact this is the whole resone WHY i am suggesting a standard here be constructed. So that if we are interested in someone's pic, we can THEN find out what are all
those other variables that you mention.

REMEMBER: This may seem like overkill for the primitive states our projects are in now...But these designs could conceivably become more and more sophisticated in the future as technology improves, gets cheaper, and gets more widely available.


It should be noted that the builder of a DIY projector will see shortcomings you as the audience might not. Likewise a builder might say "gosh I'm happy with this thing...and it's oh so bright.." but to you and I, having invested nothing in that particular setup it might look like crap.

Exactly the reason why we need a standard way to interpret results!

I realize that everybodies eyes are different...But this is the variable we need to least be worried about. We need a way to determine how YOUR diy would look to ME.
 
Re: whatever

proto5 said:

This is Proto5's last post to do anything with property- at least till he puts his $$$ where his mouth is and posts photos of his fish-tank cooled 10 million lumen blow your socks off projector that he never really intends to build. I'll be the first to eat crow if it ever happens.

Putting words in my mouth.
 
property

ok a couple of questions, 1 why dont the pro's use somthing like this? acutallualy i beleive they do and its called ansi screen lumens, u buy the machine and we will do it the same the pro's do, ok second when i post a pic and if i have a tree outside, do i count the leaves on the tree and measure them aswell and calculate how much light the tree is blocking from the sun?
o and one more thing, u know that glass in windows is not all of the same u know, some block different rays than others so we would have to have a baseline on that too i think, pluss i think weather your paint on your wall is gloss or flat, and the colour of it, the light being absorbed by carpet compered to vynal floor coverings

i mean come onnnnnnnnnnnn
Trev
 
For Instance

Look at this picture posted by Undream a few pages back:




Can you tell me what time of day it is?
Think it's 12pm? Adjust the brightness on your screen...looks like different time of day now.

What about that window on the right...is that diffuse light? Or is the sun coming through that window and the blinds are diffusing it? Where is the sun? Has the sun risen? Is the sun even lighting that room? How bright is that room? What time of day is it?

Wouldn't you like to know without having to hunt for the answers...
Wouldn't some sort of DIY standard way to at least come close to SOME KIND of interpretation of the pic be desirable?

How about something like this:

time: 12:00pm
Sun: To the Right of the room
Coming in at 45 degrees
Ratio of Brightness outside to Brightness in the Room: 100/50

Wouldn't that give you a better understanding of the pic???

No?

What if the information was the following:

Time: 5am
Sun: Right of Room 25 degrees
Ratio of Brightness outside to Brightness in the Room: 100/75

Now you have to adjust the brightness on your screen...don't you.

WOW! 3 lines of extra information...how painful.

Imagine if this was a standard that we made everybody include with their posted results...That would suck, wouldn't it?

What if we made this included information better, more useful...and of course standard...boy that would suck!!

Espescially for future (more sophisticated?) incarnation of our DIY projectors...that would sure suck!
 

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property,

You really seem to want you idea of a "standard" to fly with us. The fact of the matter, as every one above has said, is that it is simply not possible. Why not? Simple. If I am a newbie who has never built a projector and i'm looking at a result shot that says

"this picture was taken at 3:46 PM on an overcast day with the J.C. Penny brand mini blinds 3/4 closed. The light entering the room was comming in at a 180 degree from the window angle hitting the ceiling. The picture was taking with a sony 1600 digital camera "

Ok? So how does a sony 1600 render colors? How does the light coming in the room at a 180 degree angle affect the image. If these conditions are happensing, and the picture looks one way, how do i know what it will look like at 8:00 when the sun is down.

I myself have been doing this for some time now and have build all sorts of projectors. I can tell pretty well from pictures what an image really looks like and if the person is using a shitty digital camera or there projector sucks. For most people there projectors dont suck, their cameras do. You have to remember what ace said, these pictures are to guide you, not to sell projectors. Before you start designing a rating system, build a projector! Simple as that! I really think you have no clue just what thes things actually look like.

Want a rating system? Here you go... this is the best way to do it. Take your pictures at night.

Property, it seems like it only you who reall cares about this whole rating the picture thing. Well i have some news for you... People are not going to take the time to make a detailed description of their external conditions in the room just for you. Every one here knows that they can build a projector with xga and higher image quality and 300:1 contrast ratios! What does that mean? It looks good!

I want to wish you luck on you project and i urge you... read every post on this forum... even if it takes you 2 years! There is so much information just sitting here to be assimilated. Hell, if i read the forum more when i wasa newb... i would have saved alot of money.

good luck any how
 
Mustafa,

1. You are assuming i haven't read the forum.

2. You are assuming that this "standard" would just be for us and our primitive incarnations of projectors....Not for future readers, DIY builders etc...

I mean you think i want this just for "selling projectors"???

Isn't part of this forum for comparing systems???????????????????
 
Now your telling us to turn up the contrast/brightness of out monitors... but that does not change anyhting about this image... It simply makes it look washed out/dark. What you are saying we should di is borderline photoshoping an image. If anything, doing this degrades the quality of the image. Prove me wrong though... TEll me what brightess/contrast levels, resolution, refresh rate, etc to set my compaq MV720 monitor to to make undreams image look right.
 
verbose mustafa said:
Prove me wrong though... TEll me what brightess/contrast levels, resolution, refresh rate, etc to set my compaq MV720 monitor to to make undreams image look right.


I can't. I don't have basic information like time of day.

But if you had just that *ONE* piece of information, i'm sure you could make the picture approximate how it really looks much better. Try it...

Let's say it's 5am and the sun is just rising...Now adjust the picture yourself to look like what you think is 5am sun just rising...Wow! makes a big difference doesn't it? And that was just with *ONE* piece of additional information.
 
Mustafa,

Sure adjusting the pic to look like 5am sun just rising might STILL not be true...

BUT IT'LL BE A WHOLE HECK OF ALOT closer an approximation to the TRUE result than when the picture looked like 4pm mid-afternoon.

And that's just with *ONE* piece of additional information.
 
Property

Thus far I have not heard one voice that agrees with your idea of applying this "standard" ...if you feel the need to prove to us that this makes a lick of sense, I believe you will need the co-operation of some other group.

"Imagine if [ this was a standard that we made everybody include with their posted results ] ...That would suck, wouldn't it?"

Don't imagine too hard that you can push this through as some sort of "policy" with so far the only responding members saying "nay". You also have a moderator voting "nay".

"1. You are assuming i haven't read the forum."

I also have to assume you haven't read the forum, if you had you would not have concieved the notion to "amp" a panel ...as this particular idea would do nothing more than toast a perfectly good panel.

We WILL work with you, don't expect us to work FOR you.

We will work with you when you show us that you have a basic understanding of these technologies.

Don't begin to think that I am sugesting that you shouldn't "think out of the box" because thats why we are all here...to get outside the box.

Trouble arises when you "force" a rating system on anyone....play along OK? ....I've just made a major upgrade to my somewhat "un conventional approach to projection" Will I post my pictures? You bet!

(now we add the conditions you call for ) Will I post them and make some bogus "journal entries" that I for one feel no value in? No...I just won't bother posting at all.

Who looses? We all do..I loose "my shining moment in the sun"...the members loose because they don't get to see what can be done by "my methods".

All because a prerequesit to posting my pics is one that I can't live with.



Everybody want to see my "great up grade" that I made to my PJ?
Don't hold your breath...nothing new on my end...except a panel swap for one that doesn't have broken pixels. Soon though... 😉

zardoz