2.35:1 my brain hurts !!

porscheman

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Hello Guys,

This vid below is great, but I have a few questions.


If i were to buy a sony VPL HW40ES projector, for use with a 2.35:1 ratio screen, could I fill the screen full frame with 2.35:1 blu ray content by purely zooming out the projector lens so that the 'letterbox' black bars are over-projected beyond the physical screen? I assume the black bars you see when watching a 2.35:1 movie on a 16x9 screen are always present, if your projector has a native 16x9 lcd panel??

The Daniel Craig image at 1:10 on the vid looks like it would fit that screen if the PJ was zoomed out. Or am I incorrect?

Why the need for an anamorphic lens and 'electronic vertical stretch' ? Is Casino royale filmed in 2.35:1 ratio?

There must be a simple way to watch 2.35:1 and 2.40:1 movies at home?!!!
 
Last edited:
Hello Guys,


If i were to buy a sony VPL HW40ES projector, for use with a 2.35:1 ratio screen, could I fill the screen full frame with 2.35:1 blu ray content by purely zooming out the projector lens so that the 'letterbox' black bars are over-projected beyond the physical screen

Yes. Exactly what I do.
 
You are quite correct, you can zoom so that the black bars are off the top and bottom of a 2.35:1 screen. You just need enough zoom in the projector to be able to fit the screen and ideally a fairly dark screen wall (so that the black bars remain invisible).

The A-lens and vertical stretch allows the projector to use all 1080 'lines' of the projector panel. The image is scaled to fill the panel (tall and thin looking people for example), then the A-lens stretches the image optically in the horizontal direction which makes the proportions correct again.

Advantages can be; no black bars overspilling the screen. The image may be brighter than zooming* and the pixel density is higher than zooming, so the image tends to look more 'solid' for want of a better description.

Disadvantages being cost, slight reduction in ANSI contrast due to glass reflections and pincushion distortion on shorter throw set ups requires a curved screen to correct.

I used to own a fairly decent Isco II lens, but I compared using the lens with my old JVC X35 and my new X500 with e-shift (both were fully calibrated and brightness levels matched) and found that I prefer the X500 without the lens (DI was switched off to give similar contrast).

When zooming it helps to have lens memory and an external video processor that can change aspect ratios instantly too (my X500 has lens memory and I have a Lumagen VP).

True Romance said it quicker than me...

* In my set up I didn't gain any brightness compared to zooming, because the projector image can get brighter when zooming due to aperture effect in the projector lens. In my case it perfectly matched the gain from using the lens within 1%.
 
So in theory my plan will work, and I only ever watch movies in the cinema room, so 2.35:1 is the way to go for my screen when I ever get round to it :smashin:

The only thing that worries me is when viewing 16x9 I would have to zoom in I think, (not concerned about black bars either side of frame) and use lens shift to move the image up or down. This then makes acurate ceiling mounting of the PJ far more crucial ! :(

:facepalm:
 
Yes you would have to zoom back in for 16:9, whether the image moves up or down is down to various factors, but it will likely move to some degree.

You'll have to chose the throw distance very carefully as well as the ceiling mounting, though if you consider a JVC/certain Sony models with lens shift and lens memory then placement is very much easier.
 
Thanks Kelvin. Not sure if the Sony HW40ES has lens memory, and I am certain that it wont have motorised zoom, so manually changing the zoom will be a slight pain, but not a major hurdle to overcome.
 
The HW40 has no motorised zoom so obviously no lens memory, if you want to use the zoom method as I do myself don't mount the pj on the ceiling (unless you are very tall) as you will be having to stand on something every time you change aspect ratio.

My pj is placed on top of a filing cabinet so is easy and quite quick to zoom refocus and also change the height slightly to reposition the image.

I am hopefully getting a JVC pj in the next few months so will no longer have to do this.:D
 
For 16:9 I don't bother adjusting the image to fit into my 2:35 screen. I just let it over project (same as black bars), however I have devore around my screen so the image is hardly visible. You lose some of the top and bottom of the image but for how many 16:9 films I come across just lately I can't be arsed to keep adjusting the pj.

Your welcome to pop in if your ever in the midlands and see for yourself.
 
So in theory my plan will work, and I only ever watch movies in the cinema room, so 2.35:1 is the way to go for my screen when I ever get round to it :smashin:

The only thing that worries me is when viewing 16x9 I would have to zoom in I think, (not concerned about black bars either side of frame) and use lens shift to move the image up or down. This then makes acurate ceiling mounting of the PJ far more crucial ! :(

:facepalm:

The 40 has quite a wide zoom range. So yes, check out whether it'll fit first, but you'll probably be fine.

For someone whose brain hurt, you did a very good job of understanding it first go! If only all AV came that easily to us all.

Steve W
 
For 16:9 I don't bother adjusting the image to fit into my 2:35 screen. I just let it over project (same as black bars), however I have devore around my screen so the image is hardly visible. You lose some of the top and bottom of the image but for how many 16:9 films I come across just lately I can't be arsed to keep adjusting the pj.

I'll come round and lecture you later, you heathen. :D

Steve W
 
The Daniel Craig image at 1:10 on the vid looks like it would fit that screen if the PJ was zoomed out. Or am I incorrect?

Yes you are correct. Although you might see some light spill from the 'black bars' of the image on the wall.
 
Yes you are correct. Although you might see some light spill from the 'black bars' of the image on the wall.

The HW40 does have a blanking facility.

It won't mask down to 2.40:1, but it may blank off enough that the overspill is on your screen's surround, rather than the wall above and below it.

Steve W
 
The blanking facility isn't a physical one though, so the black bars will still only be as dark as the projector allows, you can't go any blacker than black if you see what I mean.

Having said that it was only back in the days of my Panasonic AE2000 that black bar overspill was visible on my dark brown screen wall, so I'd have thought a '40 would be better in this regard (so long as the screen wall isn't a light colour of course).
 
As with many PJs the shift adjusters are on the top of the Sony HW40, so if you do ceiling mount then they're on the bottom, so as long as yo can reach the lens ring from the floor you're ok.

The HW40 is fine to shift & zoom for using a 2.35:1 screen. You can potentially use some side-masking (particularly if you are using a fixed screen) when viewing 16:9 stuff.
 
Guys dont panic, my screen wall already has black flocked wallpaper on it from when I had a projector years ago. Not sure how the projected overspill black lines wiil show on this, but if it's a problem I will just paint the wall black.
 
As no one has mentioned it yet, depending on your budget you can also consider a variable aspect screen, e.g. one that has adjustable masking, this can be in the form of a blackout that lowers from the top as the screen is raised on a roller on a roll down type, which is what I have been looking at so you can have 16x9 and 2.....:1 while using the full screen width and not having to zoom the projector. Or on a fixed setup you can have adjustable masking top and bottom or on the sides or even both though it can add a lot of expense to the screen.
 
No I dont have a screen yet, but I fancy going down the diy route and it will be 2.35:1
 
I used a corded curtain track with black velvet curtains for side masking, and that worked quite well for me. I did add a wooden dowel down the leading edge to give it a sharper finish though. Electric curtains would be more swish though.

Gary
 
As no one has mentioned it yet, depending on your budget you can also consider a variable aspect screen, e.g. one that has adjustable masking, this can be in the form of a blackout that lowers from the top as the screen is raised on a roller on a roll down type, which is what I have been looking at so you can have 16x9 and 2.....:1 while using the full screen width and not having to zoom the projector. Or on a fixed setup you can have adjustable masking top and bottom or on the sides or even both though it can add a lot of expense to the screen.

I have one - slightly different masking system.

See link in sig.

Steve W
 
The blanking facility isn't a physical one though, so the black bars will still only be as dark as the projector allows, you can't go any blacker than black if you see what I mean.

Having said that it was only back in the days of my Panasonic AE2000 that black bar overspill was visible on my dark brown screen wall, so I'd have thought a '40 would be better in this regard (so long as the screen wall isn't a light colour of course).

The 'black' output on the Sony is pretty good.

To be honest, with good velvet borders, it's difficult to see white projected on as overspill.

Steve W
 
No I dont have a screen yet, but I fancy going down the diy route and it will be 2.35:1
If I were to make another screen I would definitely think about gluing in some small magnets into the frame (front) to enable a possible side-masking system... using magnets;). That's if you have room to store some removable side panels. But there are some truly inspiring DIY screen threads on the forum (one not very long ago) which can look very professional.
 
Steve
How are the panels, any sagging of the velvet covering at all?

No.

The only slight issue - where the glue has come unstuck a little, and the staples are spaced, you get a very slightly uneven edge.

If I were to start again I'd wrap the velvet around the masks rather than along them, and use more staples.

However, watched Apocalypse Now last night with the friend who helped me with the room. He saw the uneven edge whilst we were setting up, but neither of us noticed it whilst watching the film.

Steve W
 

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