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Recommendations For Projector Size/material - 4 Metre Viewing Distance

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#26 minty

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Posted 09 March 2012 - 03:13 PM

View PostMarkTecher, on 09 March 2012 - 09:21 AM, said:

This thread is a perfect example of why the finding the screen height based on room length first (and not seating distance first) is the way to go.  The OP wants to know how big a screen he can have from a 4m viewing distance and people are providing examples based on thier personal preferences which may or may not suit the OP.

The place to start is knowing how big the room is first so we can work out how large the screen is, then find the seating distance based on that.  If you work reverse, it is guess work as this thread is proving.  If you were to base the screen height on say a 15 degree vertical viewing angle, you get a max of 1072mm for 4m and I personally think that is an undersize if your room is 6m deep.  

OP:  How big is the room we are dealing with?
The OP has said he wants a screen size based on seating at 3.5 to 4m.
So going by your post if he happens to have a room 8m x 5m he should fit a screen relative to that size room, which I would imagine would be huge and totally unpleasant to view from 3.5m away.
So now it's room size not seating distance that dictates screen size? Pretty much the opposite of the advice you've given in the past.

#27 roh008

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Posted 09 March 2012 - 06:29 PM

Hi All,

Wow a lot has been written since I last visited the thread thanks for input.

Ok so limiting factors are the key here. Screen width. As I posted earlier in my potential set up the screen + floor standers either side are what's going to limit me. Room width is around 4 meters but the catch is floor standers can't be pushed up against the side of the room so need to be around 40cms from the wall. However, the screen will be off centre of the room as there is a fire place on one wall and a sofa against the other.
The prime seats will be around the 3.7-4 back from dead centre of the screen. The other sofa is perpendicular to the prime seat along the left hand wall and around a meter closer. This will be around 3.2ish meters from the screen, the seat closest will be too close so redundant (1.5 meters away or less from the screen centre).

Currently sitting 3.3-3.5meters from a 1.65 meter wide screen measured on wall while watching a cinemascope movie so had black bars and I feel it's like watching a large tv rather than the cinema feel.
The 16:9 free to air content is a good size but still could be bigger (no black bars in that case but same screen width.

Based on that I am trying to work out what size screen i'll need

#28 roh008

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Posted 09 March 2012 - 06:30 PM

The two seater is now a 3 seater hence closer to the area where the speaker and screen will be. Will potentially flip the room around and put the projector screen with no TV where the 3 seater is at the moment and have that room with no tv and just projector. Will potentially open the room up nicely as well.
Posted Image

Edited by roh008, 09 March 2012 - 06:50 PM.


#29 :)

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Posted 09 March 2012 - 07:26 PM

thats a little similar to the open plan setup at my place. with a lounge room with exactly the same seating layout opening out to a larger open plan kitchen and dining area. I have the screen located in orientation same as you do. though my room is about a couple meters wider. I agree you dont want your speakers stuck up against side walls 300/400 - 600mm what Id try to achieve at a minimum.

I'd stick to the arrangement shown in the last pick. rather than swap screen position around. pity the large windows on the back wall. otherwise could wall mount the display there. Also makes easier for mounting centre speaker. I would stick to the display too. with a motorised screen as will give a bit more multipurpose use for an area such as this.

presume the opening between the lounge area and dining can be closed off ? can be handy as will give dual use of the area. OT for here but have you consider speaker placement for sides and rears and sub ? 5.1/7.1 ?

#30 roh008

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Posted 09 March 2012 - 09:01 PM

Hi Al,

Will be running 5.1 mounting the rears on the bits that stick out on either side of the sofa.

#31 roh008

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Posted 10 March 2012 - 06:19 PM

how can i work out how low a light fitting  i can have without it getting in the way of the top of the screen? 4.6m screen to projector. projector fixing has 200mm drop..

#32 MarkTecher

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Posted 10 March 2012 - 07:51 PM

View Postseatonrocks, on 09 March 2012 - 03:13 PM, said:

The OP has said he wants a screen size based on seating at 3.5 to 4m.
Correct.

Quote

So going by your post if he happens to have a room 8m x 5m he should fit a screen relative to that size room, which I would imagine would be huge and totally unpleasant to view from 3.5m away.

And why I asked that he provide more information about the room.  He has since supplied a diagram showinng the room.  Yes it would be sad if his 8 meter room was a dedicated and could support a larger screen and he went to small because of a mis-understanding that he wants to sit close.  

Quote

So now it's room size not seating distance that dictates screen size? Pretty much the opposite of the advice you've given in the past.

I've always suggested starting with the room length first.  My whole room design formula is based on the room length being the key to work out both screen size and seating distances

Have a read of THIS

Incase you can't be bothered (because you'd rather make a personal attack to discredit me for what ever your reason is), here is the part I am talking about:

Quote

1. Taking the room’s length and dividing it by a number within the given values on the diagram
I am talking about starting with the room length to find the idea screen size.  I always have done this since at least 2002.

#33 MRCRIST

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Posted 10 March 2012 - 07:55 PM

Mark Techer is one  guy who knows his HT stuff. Any feeble attempt to discredit him will always be egg on the face of the perpretrator.

Edited by MRCRIST, 11 March 2012 - 09:21 AM.


#34 roh008

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Posted 11 March 2012 - 12:50 AM

Hi guys,

Firstly Mark, just to let you know that I appreciate your help, and as it's my thread, (you don't need to waste your time justifying to anyone else your reasonings).
On a separate note i do feel people mis interpret what is written in a lot of forum threads and then it goes off in a tangent and people take offence.

Secondly, excluding the dining room the living area (not dedicated HT room) is roughly 5.6x 4.45. However as you can see from the diagram, there is a fireplace(slightly bigger than shown) on one side and a three seater sofa(not 2 anymore) on the opposite side which comes out 1.4 meters due to heating vent behind it. With the other 3 seater splitting the two rooms.

The both sofas are 2 meters long and the one against the wall has to start after the entrance of the door which is why it's close to what is now going to be the projector screen.

We are considering flipping the room and dropping the projector screen in the void and put the L/R channels where the nib walls come out. For movies i'll have a centre channel on a stand which I'll move to the middle and for music i won't need the centre present. There will be no TV in that room is the alternate set up. Family Room can have that. (no the family room can't be used for movies due to tiled floor and opened room(forms kitchen and breakfast room as well, open plan).


Current issue for me is working out at the mid point between projector and screen assuming screen height from floor is 70cm up and it's a 2.7m heigh room.

Currently looking at light fitting with 45cm drop in the middle of the room.

#35 minty

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Posted 11 March 2012 - 09:58 AM

View PostMarkTecher, on 10 March 2012 - 07:51 PM, said:

Correct.


And why I asked that he provide more information about the room.  He has since supplied a diagram showinng the room.  Yes it would be sad if his 8 meter room was a dedicated and could support a larger screen and he went to small because of a mis-understanding that he wants to sit close.  



I've always suggested starting with the room length first.  My whole room design formula is based on the room length being the key to work out both screen size and seating distances

Have a read of THIS

Incase you can't be bothered (because you'd rather make a personal attack to discredit me for what ever your reason is), here is the part I am talking about:

I am talking about starting with the room length to find the idea screen size.  I always have done this since at least 2002.

When someone disagrees with you or criticisers you, why do you cry out "personal attack" ? Clearly this was not a personal attack on you, it was pointing out a clear fact that you have said things in the past such as..........



The best way to find the ideal seating location is to use the screen height, not the width. All of the calculators are based on width for 16:9, yet they all seem to want to share THX's 36 degrees. Infact THX's latest method is to take the screen width and divide it by 0.728 - ie 2400mm / 0.728 = 3297mm and that is fine as I will explain soon...

SMPTE stands for the Society of Motion Pitcures and Television Engineers. and have always worked off the height. And it makes perfect sense if the 1 in the X:1 ratio is always the screen height.

There recommendations are much simplier than anything else around where the absolute closest is 2x and the fartherest is 4x the screen height - again regardless of aspect ratio. This is based on the fact that we are more sensitive to tall picture than a wide picture - our eyes can track horizontally much easier then vertically.



You said that in a post 3 years ago. I could quite easily find many more but really, it's beautiful outside and surfing waves appeals much more than surfing for contradictory Techer posts, as simple and as plentiful as they are to find.

Seeing as the OP in this thread had already said what his seating distance was, the information required was what size screen/projector was recommended. SMPTE figures as quoted by you give a distance of between 2 and 4 times distance back from the screen height. OP wants to sit at 4m, that would make a screen height of approx. 1.33m regardless of AR and is worked out on the basis that 3 x the screen height back from screen is ideal (SMPTE as quoted by you say between 2-4, so 3 would be ideal, yes?).

Room length is irrelevant and to emphasize this point here is a post from a respected forum member who sells screens for a living telling you as much...........


Yes you are right there Rod, the room length has no bearing on the screen size.

This should be replaced with distance of eyes from screen.

Some rooms will be 6 metres deep but people have their seats at different distances.
My eyes are at roughly 5.3 metres from the screen. Others will prefer anything from 3 to 5.5 metres.

Some rooms will be dual purpose rooms, say 10 metres deep, but the cinema seats may be 3.2 from the screen.

I am given room sizes all the time, I bypass that at the beginning and ask how far back your eyes
are going to be from the screen
(the room could be 15 metres deep but this makes no impact on screen size unless their
seats are at the very back of the room, unlikely), then take into account the projector resolution, closest seating position
(rows of seats, if any), light output from projector (no point having a massive screen if it lacks lumens)
and a few other little tricks. Can usually get it near perfect without any formulas.




That is from Oztheatre, but i guess you already knew that. Read it closely and note it is distance from eyes to screen that is relevant, your room size theory is blown out of the water pretty much every time, and hence why over the years you have numerous times recommended the SMPTE or THX figures for ideal seating locations, conveniently not mentioning your room size theory because it is flawed.

Not a personal attack bud, just pointing out facts.

#36 minty

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Posted 11 March 2012 - 10:19 AM

View PostMRCRIST, on 10 March 2012 - 07:55 PM, said:

Mark Techer is one  guy who knows his HT stuff. Any feeble attempt to discredit him will always be egg on the face of the perpretrator.

Like many experts in all sorts of different fields, they like to complicate matters to prove their worth and/or display their vast knowledge. Your a Techer fanboy and carry issues over from other threads, so no surprise you would post this sort of response.

Seating to screen distance is all that's relevant, especially in this thread where the seating distance was already known. He's got to try and justify the paper he's written, but if you go and use his room length theory in a practical situation you will more often than not find you and him will be the only ones with egg on their faces.

Edited by seatonrocks, 11 March 2012 - 10:22 AM.


#37 minty

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Posted 11 March 2012 - 10:35 AM

More..........


I give up Mark.

Room length has nothing to do with screen size. Seating distance, your front wall size, WAF and preferred viewing angles do. Your room can be 100m long and it will HAVE NOT EFFECT on what you want to do with wear you sit with the projecting wall. I am not arguing against SMPTE viewing angle recommendations indeed they should be used when calculating screen size, particularly the viewing angel recommendations - which are once again not affected by how long your room is rather it is affected by where you are sitting and the size of the screen.

I think you need to get out of the books and think about what it is you are saying. I have already given you a ridiculous room length of 20m and you have provided a nice healthy (and rather equally ridiculous) screen height of 5.xm.

Now if that doesn't make someone realise that room length has nothing to do with your preferred viewing size (and distance) does I don't know what will.

Its quite simple - you have a preferred seating distance and a prefered viewing angle. This puts people into your 2x to 4x screen zone quite nicely which is good advice. Advice actually that could be USED OUTSIDE! style_emoticons/default/smile.gif



Taken from the same thread as the earlier ones at the following http://www.dtvforum....opic=62461&st=0

#38 roh008

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Posted 11 March 2012 - 11:00 AM

Guys don't worry about it, haven't given room length as it would just complicate matters. I've given a range of seating positions. Prime seats will be 4meters +-20cms and the other sofa will be on the side wall and closer 2.8m +-20cms at one end with the other end begin too close so that seat will not likely to be used.

However, can anyone put their effort in helping me work out what the light path from projector to screen will be as we have no option to move the light from the centre of the room. We have found a light we like with a 40ish cm drop from the ceiling. (ceiling height is 2700mm,) we are likely to put the bottom of the screen 700mm from the ground.

The screen I think is around 1.4meters high if I go for 112" 1.27m for 102".

The projector is attached to a 200mm bracket.

Anyone know the formula I can use?

Thanks

Roh

#39 minty

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Posted 11 March 2012 - 11:42 AM

View Postroh008, on 11 March 2012 - 11:00 AM, said:

Guys don't worry about it, haven't given room length as it would just complicate matters. I've given a range of seating positions. Prime seats will be 4meters +-20cms and the other sofa will be on the side wall and closer 2.8m +-20cms at one end with the other end begin too close so that seat will not likely to be used.

However, can anyone put their effort in helping me work out what the light path from projector to screen will be as we have no option to move the light from the centre of the room. We have found a light we like with a 40ish cm drop from the ceiling. (ceiling height is 2700mm,) we are likely to put the bottom of the screen 700mm from the ground.

The screen I think is around 1.4meters high if I go for 112" 1.27m for 102".

The projector is attached to a 200mm bracket.

Anyone know the formula I can use?

Thanks

Roh

You are quite correct, room length would just complicate matters and is completely irrelevant and is why i've been banging on about it for several posts. People will try and confuse you with useless info when it is really quite simple. Based on the info you gave in your very first post wrt seating distance, the 1.4m high screen you are thinking about would be mint and what SMPTE & THX  would show is an excellent choice.

You would need to keep the projectors light beam out of the path of the light fitting (obviously), so going by your measurements you will have 600mm from top of screen to ceiling. The lens of the projector normally aligns with the top of the screen so with the light fitting extending down 400mm you should be good to go, just need to get the lens down 600mm from ceiling.

#40 MRCRIST

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Posted 11 March 2012 - 12:08 PM

View Postseatonrocks, on 11 March 2012 - 10:19 AM, said:

Like many experts in all sorts of different fields, they like to complicate matters to prove their worth and/or display their vast knowledge. Your a Techer fanboy and carry issues over from other threads, so no surprise you would post this sort of response.

Seating to screen distance is all that's relevant, especially in this thread where the seating distance was already known. He's got to try and justify the paper he's written, but if you go and use his room length theory in a practical situation you will more often than not find you and him will be the only ones with egg on their faces.

Mmm :no: :hyper:  must barrack for the pies :pirate: . PS Bucks has no idea what he is doing :queen: . Fancy getting smashed by the Crows

Edited by MRCRIST, 11 March 2012 - 12:09 PM.


#41 MarkTecher

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Posted 11 March 2012 - 12:30 PM

View Postroh008, on 11 March 2012 - 12:50 AM, said:

Secondly, excluding the dining room the living area (not dedicated HT room) is roughly 5.6x 4.45. However as you can see from the diagram, there is a fireplace(slightly bigger than shown) on one side and a three seater sofa(not 2 anymore) on the opposite side which comes out 1.4 meters due to heating vent behind it. With the other 3 seater splitting the two rooms.

So the actually "workable" room is 5.6 x 4.45 x 2.7M?

Without all the confusion and upset, based on this, the largest screen you would want is 1.5m tall and the smallest is just over a meter.  It is still based on your room length.

Because you have already stated you want to sit 4m away, you have no choice but to reduce the screen height to about 1.33m (3x IH) and I will suggest that your said 1.4m (2.8x IH) will also be quite good.  I personally like to sit at 2x IH and do so in my own room but that is me and it is not for everyone.  

Given you are skilled in Sketch Up (a very useful tool for this), I would be removing a side wall off your drawing then adding in the ceiling and any fixtures, then draw (or import) yourself the projector and proposed screen.  The beam angles from the projector to the screen will be straight lines (you can use guidelines for these) to ensure that you won't clip anything on the way to the screen.  If you create the screen and projector as a 'component' or 'group' you can then move them (up or down) to find the best height for both.  You can also draw in your seated eye height and using the protractor, check the angles to the top of the screen.

I did an example of this HERE.

#42 minty

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Posted 11 March 2012 - 12:33 PM

View PostMRCRIST, on 11 March 2012 - 12:08 PM, said:

Mmm :no: :hyper:  must barrack for the pies :pirate: . PS Bucks has no idea what he is doing :queen: . Fancy getting smashed by the Crows

A 12yo Techer fanboy no less. Thanks for your imput to the thread. Invaluable.

#43 :)

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Posted 11 March 2012 - 12:41 PM

View Postroh008, on 11 March 2012 - 11:00 AM, said:

Guys don't worry about it, haven't given room length as it would just complicate matters. I've given a range of seating positions. Prime seats will be 4meters +-20cms and the other sofa will be on the side wall and closer 2.8m +-20cms at one end with the other end begin too close so that seat will not likely to be used.

However, can anyone put their effort in helping me work out what the light path from projector to screen will be as we have no option to move the light from the centre of the room. We have found a light we like with a 40ish cm drop from the ceiling. (ceiling height is 2700mm,) we are likely to put the bottom of the screen 700mm from the ground.

The screen I think is around 1.4meters high if I go for 112" 1.27m for 102".

The projector is attached to a 200mm bracket.

Anyone know the formula I can use?

Thanks

Roh

no one formula. is it a scope screen or 16:9 ?

only factors are how far dropped is the top of the projector lens from the ceiling. how far dropped is the top of screen from the ceiling. how far apart are the projector, light and screen. draw a line on a piece of paper to scale from projector top of lens to top of screen and see if it misses the 400mm dropped light. thats it.

if already in the room can use a string pegged to where top of pj lens is going to be and take it to top of the drop of the screen. if intersects the light your either going to have to drop the pj or the screen :)

#44 MRCRIST

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Posted 11 March 2012 - 01:43 PM

View Postseatonrocks, on 11 March 2012 - 12:33 PM, said:

A 12yo Techer fanboy no less. Thanks for your imput to the thread. Invaluable.


Typical collingwood supporter :no: everything is black and white... oh well another.... 19 years to wait for your next flag. :D

And why are you taking swipes at Mark Techer's fan club? I must barrack for Geelong...go cats!!!!!!!!


PS Thanks for your valuble input.

Edited by MRCRIST, 11 March 2012 - 01:53 PM.


#45 minty

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Posted 11 March 2012 - 02:15 PM

View PostMRCRIST, on 11 March 2012 - 01:43 PM, said:



Typical collingwood supporter :no: everything is black and white... oh well another.... 19 years to wait for your next flag. :D

And why are you taking swipes at Mark Techer's fan club? I must barrack for Geelong...go cats!!!!!!!!

How're the eggs tasting, or are you still busy wiping them off your face? Rather than the cheap shots and feeble attempts at ridiculing me, which btw are only digging that hole you find yourself in deeper and deeper and showing your obvious lack of tact, how about responding to what brought you here in the first place? Namely how you jumped into a thread with no other purpose than because of your dislike for me. You obviously have limited knowledge of what's being discussed otherwise you would have stayed out. And now all you can come up with are Collingwood jokes. Wow how original. So explain to everyone how room length in this thread has any relevance considering the op has declared his seating distance as 4m. No, i thought so, no idea? On 2nd thoughts go back to the Collingwood jokes, they show the chip on your shoulder, jealousy and lack of intelligence off to great effect.

#46 roh008

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Posted 11 March 2012 - 04:16 PM

View Postseatonrocks, on 11 March 2012 - 11:42 AM, said:

You would need to keep the projectors light beam out of the path of the light fitting (obviously), so going by your measurements you will have 600mm from top of screen to ceiling. The lens of the projector normally aligns with the top of the screen so with the light fitting extending down 400mm you should be good to go, just need to get the lens down 600mm from ceiling.

Realistically it's going to have to be the smaller screen :( 102" and that's a squeeze due to width limitation.

Re light fitting -  was planning on using vertical lens shift to get around this, as wife wouldn't be too happy having projector that low( from ceiling 60cms). It's being put in the middle part of the dining/living room gap. so around 2700mm-200mm mount arm minus distance from top of projector to lens so around 100mm again. so 2.4m then use lens shift to move it down some more.

#47 MRCRIST

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Posted 11 March 2012 - 11:41 PM

View Postseatonrocks, on 11 March 2012 - 02:15 PM, said:

How're the eggs tasting, or are you still busy wiping them off your face? Rather than the cheap shots and feeble attempts at ridiculing me, which btw are only digging that hole you find yourself in deeper and deeper and showing your obvious lack of tact, how about responding to what brought you here in the first place? Namely how you jumped into a thread with no other purpose than because of your dislike for me. You obviously have limited knowledge of what's being discussed otherwise you would have stayed out. And now all you can come up with are Collingwood jokes. Wow how original. So explain to everyone how room length in this thread has any relevance considering the op has declared his seating distance as 4m. No, i thought so, no idea? On 2nd thoughts go back to the Collingwood jokes, they show the chip on your shoulder, jealousy and lack of intelligence off to great effect.

You really need a reality check.
You come on this forum as a "Johnny come lately" and attempt to undermine one our senior members who has been most helpful to a lot of us in the past and still is in the present.
If you can't remember or recall what you wrote I suggest you look above .

Mark's "sticky" on multichannel calibration was informative and most helpful to a vast number of new members at the time including myself.
I even called Mark on several occasions for assistance and advice while I was calibrating my room several years ago. Mark was most helpful and this is about all my involvement with Mark.
You see I am not a fanboy as you have labelled me but rather someone who respects a person for performing a good deed on more than one occasion.
I do not dislike you...I don't know who you are. But when someone comes on this forum an attempts to belittle someone who has helped me  I will defend that person full stop.

My attempt to fire back some missiles by having a go at the Collingwood Football club  and stereotyping their supporters I admit was ordinary.

Edited by MRCRIST, 11 March 2012 - 11:58 PM.


#48 minty

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Posted 12 March 2012 - 10:32 AM

View PostMarkTecher, on 09 March 2012 - 09:21 AM, said:

This thread is a perfect example of why the finding the screen height based on room length first (and not seating distance first) is the way to go.  The OP wants to know how big a screen he can have from a 4m viewing distance and people are providing examples based on thier personal preferences which may or may not suit the OP.

The place to start is knowing how big the room is first so we can work out how large the screen is, then find the seating distance based on that.  If you work reverse, it is guess work as this thread is proving.  If you were to base the screen height on say a 15 degree vertical viewing angle, you get a max of 1072mm for 4m and I personally think that is an undersize if your room is 6m deep.  

OP:  How big is the room we are dealing with?


View Postseatonrocks, on 09 March 2012 - 03:13 PM, said:

The OP has said he wants a screen size based on seating at 3.5 to 4m.
So going by your post if he happens to have a room 8m x 5m he should fit a screen relative to that size room, which I would imagine would be huge and totally unpleasant to view from 3.5m away.
So now it's room size not seating distance that dictates screen size? Pretty much the opposite of the advice you've given in the past.


View Postseatonrocks, on 11 March 2012 - 09:58 AM, said:

When someone disagrees with you or criticisers you, why do you cry out "personal attack" ? Clearly this was not a personal attack on you, it was pointing out a clear fact that you have said things in the past such as..........



The best way to find the ideal seating location is to use the screen height, not the width. All of the calculators are based on width for 16:9, yet they all seem to want to share THX's 36 degrees. Infact THX's latest method is to take the screen width and divide it by 0.728 - ie 2400mm / 0.728 = 3297mm and that is fine as I will explain soon...

SMPTE stands for the Society of Motion Pitcures and Television Engineers. and have always worked off the height. And it makes perfect sense if the 1 in the X:1 ratio is always the screen height.

There recommendations are much simplier than anything else around where the absolute closest is 2x and the fartherest is 4x the screen height - again regardless of aspect ratio. This is based on the fact that we are more sensitive to tall picture than a wide picture - our eyes can track horizontally much easier then vertically.



You said that in a post 3 years ago. I could quite easily find many more but really, it's beautiful outside and surfing waves appeals much more than surfing for contradictory Techer posts, as simple and as plentiful as they are to find.

Seeing as the OP in this thread had already said what his seating distance was, the information required was what size screen/projector was recommended. SMPTE figures as quoted by you give a distance of between 2 and 4 times distance back from the screen height. OP wants to sit at 4m, that would make a screen height of approx. 1.33m regardless of AR and is worked out on the basis that 3 x the screen height back from screen is ideal (SMPTE as quoted by you say between 2-4, so 3 would be ideal, yes?).

Room length is irrelevant and to emphasize this point here is a post from a respected forum member who sells screens for a living telling you as much...........


Yes you are right there Rod, the room length has no bearing on the screen size.

This should be replaced with distance of eyes from screen.

Some rooms will be 6 metres deep but people have their seats at different distances.
My eyes are at roughly 5.3 metres from the screen. Others will prefer anything from 3 to 5.5 metres.

Some rooms will be dual purpose rooms, say 10 metres deep, but the cinema seats may be 3.2 from the screen.

I am given room sizes all the time, I bypass that at the beginning and ask how far back your eyes
are going to be from the screen
(the room could be 15 metres deep but this makes no impact on screen size unless their
seats are at the very back of the room, unlikely), then take into account the projector resolution, closest seating position
(rows of seats, if any), light output from projector (no point having a massive screen if it lacks lumens)
and a few other little tricks. Can usually get it near perfect without any formulas.




That is from Oztheatre, but i guess you already knew that. Read it closely and note it is distance from eyes to screen that is relevant, your room size theory is blown out of the water pretty much every time, and hence why over the years you have numerous times recommended the SMPTE or THX figures for ideal seating locations, conveniently not mentioning your room size theory because it is flawed.

Not a personal attack bud, just pointing out facts.

View Postseatonrocks, on 11 March 2012 - 10:35 AM, said:

More..........


I give up Mark.

Room length has nothing to do with screen size. Seating distance, your front wall size, WAF and preferred viewing angles do. Your room can be 100m long and it will HAVE NOT EFFECT on what you want to do with wear you sit with the projecting wall. I am not arguing against SMPTE viewing angle recommendations indeed they should be used when calculating screen size, particularly the viewing angel recommendations - which are once again not affected by how long your room is rather it is affected by where you are sitting and the size of the screen.

I think you need to get out of the books and think about what it is you are saying. I have already given you a ridiculous room length of 20m and you have provided a nice healthy (and rather equally ridiculous) screen height of 5.xm.

Now if that doesn't make someone realise that room length has nothing to do with your preferred viewing size (and distance) does I don't know what will.

Its quite simple - you have a preferred seating distance and a prefered viewing angle. This puts people into your 2x to 4x screen zone quite nicely which is good advice. Advice actually that could be USED OUTSIDE! style_emoticons/default/smile.gif



Taken from the same thread as the earlier ones at the following http://www.dtvforum....opic=62461&st=0


View PostMRCRIST, on 11 March 2012 - 11:41 PM, said:

You really need a reality check.
You come on this forum as a "Johnny come lately" and attempt to undermine one our senior members who has been most helpful to a lot of us in the past and still is in the present.
If you can't remember or recall what you wrote I suggest you look above .

Mark's "sticky" on multichannel calibration was informative and most helpful to a vast number of new members at the time including myself.
I even called Mark on several occasions for assistance and advice while I was calibrating my room several years ago. Mark was most helpful and this is about all my involvement with Mark.
You see I am not a fanboy as you have labelled me but rather someone who respects a person for performing a good deed on more than one occasion.
I do not dislike you...I don't know who you are. But when someone comes on this forum an attempts to belittle someone who has helped me  I will defend that person full stop.

My attempt to fire back some missiles by having a go at the Collingwood Football club  and stereotyping their supporters I admit was ordinary.

So now we are getting down to the real issue, the real issue all along in your mind is that i'm a "Johnny come lately", therefore i don't have the right to question a senior member giving out advice that has been proved wrong in the past. And also the said senior member has helped a lot of people in the past, therefore according to you he can say anything whether right or wrong or misleading and no-one is allowed to dispute it. Oh, hang on, i mean little, inexperienced, johnny come lately members can't dispute him, correct? And to think some of you guys think it would be a good idea to let some senior members have certain mod powers, if only to suspend someone for 24-48 hrs, wow wouldn't that be awesome if you had that kind of power Crist, you could have suspended me and deleted my post too. Stuff freedom of speech, lets just hear what we want to hear.

I've quoted above what i posted, there's no malice, no undermining, just the cold hard facts relative to the advice asked for in THIS THREAD. I suggest YOU go back and read them, and try to understand what is being discussed as you clearly don't, especially the very first post, and also note that not too many people are running in to defend a Senior member who is supposedly being undermined and belittled by a "Johnny come lately".

Can i ask, what the hell has "Mark's "sticky" on multichannel calibration" got to do with anything? This thread is about seating distance from screen, not multichannel calibration. So this is the extent of things, along with the johnny come lately remark of course, because "Mark helped me therefore i will defend him even though i have no friggin' idea what i am talking about".

So to sum up, your contribution to this thread has been zero advice given to the OP and subject matter (probably because you have no idea, obviously), one or two Collingwood jokes/ridiculing, and now telling me i have no right to question a Snr member because i'm a "Johnny come lately" and Mark has helped you in the past.

That's really good Crist, you can feel proud of that.

Whilst deciphering this post you may like to also mull over the fact that hey, post count high or low, Snr member or not, there are many informed HT enthusiasts out in the real world. Some of us "Johnny come latelys" have even had front projection and surround sound systems for 2 decades.

No Crist i don't require the reality check, but i know who does.

Grow up.

#49 MRCRIST

MRCRIST

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Posted 12 March 2012 - 11:05 AM

View Postseatonrocks, on 12 March 2012 - 10:32 AM, said:

So now we are getting down to the real issue, the real issue all along in your mind is that i'm a "Johnny come lately", therefore i don't have the right to question a senior member giving out advice that has been proved wrong in the past. And also the said senior member has helped a lot of people in the past, therefore according to you he can say anything whether right or wrong or misleading and no-one is allowed to dispute it. Oh, hang on, i mean little, inexperienced, johnny come lately members can't dispute him, correct? And to think some of you guys think it would be a good idea to let some senior members have certain mod powers, if only to suspend someone for 24-48 hrs, wow wouldn't that be awesome if you had that kind of power Crist, you could have suspended me and deleted my post too. Stuff freedom of speech, lets just hear what we want to hear.

I've quoted above what i posted, there's no malice, no undermining, just the cold hard facts relative to the advice asked for in THIS THREAD. I suggest YOU go back and read them, and try to understand what is being discussed as you clearly don't, especially the very first post, and also note that not too many people are running in to defend a Senior member who is supposedly being undermined and belittled by a "Johnny come lately".

Can i ask, what the hell has "Mark's "sticky" on multichannel calibration" got to do with anything? This thread is about seating distance from screen, not multichannel calibration. So this is the extent of things, along with the johnny come lately remark of course, because "Mark helped me therefore i will defend him even though i have no friggin' idea what i am talking about".

So to sum up, your contribution to this thread has been zero advice given to the OP and subject matter (probably because you have no idea, obviously), one or two Collingwood jokes/ridiculing, and now telling me i have no right to question a Snr member because i'm a "Johnny come lately" and Mark has helped you in the past.

That's really good Crist, you can feel proud of that.

Whilst deciphering this post you may like to also mull over the fact that hey, post count high or low, Snr member or not, there are many informed HT enthusiasts out in the real world. Some of us "Johnny come latelys" have even had front projection and surround sound systems for 2 decades.

No Crist i don't require the reality check, but i know who does.

Grow up.


Ok time to calm down and take a deep breath.

#50 roh008

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Posted 12 March 2012 - 03:59 PM

GUYS! Please keep this conversaton off my  thread. This is not the place to discuss such issues. I honestly have not come across a forum that has so many arguments!
I am starting to feel that I'm better of staying with AVS/AV forums as there isn't as much of this! I've moved to AUS so felt I should join to be more part of the Aus online community, but the number of these altercations I have come across on DTV is far more than the others and I've only been on this one for a very short time!

I appreciate USEFUL input.

Many Thanks

Roh