Help with what a Anamorphic Lens does

[admin_exported]

Hi there i have made my mind up and will be buying an JVC X3 at some point this year. I will be totally new to the Projector world so please bare with me!

My dilema is should i go 16:9 or 2:35.1 screen. My set up would consist of Sky HD/Blu-Ray Player/Apple TV/PS3. I would say i am mainly a Sport & Movies man with the occasional 'Normal TV' & Gaming. From what i have read for Movies a 2:35.1 screen would be ideal and for Sky HD a 16:9 would be better so i am really stuck between the two?

I then come across posts about Anamorphic Lens could anyone give me a brief & to the point discription about what an Anamorphic Lens does & if i had the funds how it would help me? What would an do if i was watching a 2:35.1 movie on a 2:35.1 screen? or is it basically to convert a 16:9 image onto a 2:35.1 screen?

One last question i have seen some Curved Screens would a curve increase the picture quality of a projectors image?

Thanks
Andy

 

[Tom Moreno]

Hi Andy,

Lucky boy! Good luck with the dla-x3, very jealous.

If you love watching films and the majority of your viewing is film then setting up a 2.35-1or "constant height" system is a worthwhile consideration for ultimate wow factor. To achieve a CH setup there are two ways to go about it on the projector, one is using the zoom on the lens to essentially push the black bars off the screen and the other is to use an anamorphic lens that can be positioned in and out of the light path. The zoom method's advantage is cost but the disadvantage is that you lose a bit of brightness by exploding the image. Also not every projector makes this kind of switching between zoom/focus points easy and many must be adjusted manually every time you wish to change aspect ratio. The advantage of using an anamorphic lens is that the image is processed inside the projector to stretch to the full height of the 16:9 imaging chip and then stretched wide by the optics of the lens so none of the light from the projector is being wasted on your wall above and below the screen thus giving you all the brightness and "pop" of a standard 16:9 projection from your projector. The disadvantage is mainly in the cost of the extra lens and sled configuration. Another point to consider as your getting a 3d projector is that the JVC will not allow a 3d signal to be displayed in an anamorphic 2.35:1 presentation. With regards to curved screens- this is for use with the lens system as the anamorphic lenses can introduce a slight distortion to the image at it's edges and the curve if the screen (like in the movie theatres) allows the image to be in focus from edge to edge.

Hope some of this info helps you out. Good luck. And once you get set up please post pics of you system in the "Your System" section of the forum for us all to drool over!

 

[Anonymous]

So just to confirm a anamorphic lens can not work with 3D?

Also you do not need a anamorphic lens with a 2:35.1 screen?

 

[chudleighpaul]

Andy, you do not need an anamorphic lens. It will have the effect of stretching everything horizontaly.

To fill a 2.35:1 screen all you need to do is to use the zoom on the projector.

 

[chudleighpaul]

The purpose of an anamorphic lens was for the cinemascope process. A 4:3 camera with an anamorphic lens was used and this squeezed a 2.25 image onto the standard 4:3 film frame.

When the film was shown in the cinema an anamorphic lens was fitted to the projector, which had the effect of unsqueezing the image and displaying it as 2.35:1

The image from a Sky movies, DVD or Bluray source is in the correct proportion already, so an anamorphic lens would have the effect of distorting it.

 

[Tom Moreno]

chudleighpaul:
Andy, you do not need an anamorphic lens. It will have the effect of stretching everything horizontaly. To fill a 2.35:1 screen all you need to do is to use the zoom on the projector.

chudleighpaul:
The purpose of an anamorphic lens was for the cinemascope process. A 4:3 camera with an anamorphic lens was used and this squeezed a 2.25 image onto the standard 4:3 film frame.

When the film was shown in the cinema an anamorphic lens was fitted to the projector, which had the effect of unsqueezing the image and displaying it as 2.35:1

The image from a Sky movies, DVD or Bluray source is in the correct proportion already, so an anamorphic lens would have the effect of distorting it.

The downside of zooming the image to fill a 2.35:1 screen is the drop in brightness by shooting light above and below the screen. Most modern high-end projectors have modes for use with anamorphic lenses where the proj's processor stretches the image height-wise to fill the entire 16:9 imaging chip(s) in order for the lens to stretch the image widthwise to the correct aspect ratio on screen while using the entire brightness offered by the light engine of the projector without loss. The other downside to using zoom to fill a 2.35:1 screen is that many projectors (and I believe JVC's in particular) require you to manually go through the whole adjustment procedure to zoom and focus every time you want to change aspect ratio. The Panasonic PT-AE series projector's are famous for having a few lens setting memories that you can use to quickly change back and forth between zoom modes for aspect ratio but from what I've read quite a few other projectors can prove to be quite a faff to go back and forth.

Andy, going back to the 3D question- I read specifically in the JVC manual that the processing mode required for anamorphic presentation cannot be engaged when viewing in 3D. Now I don't know how much this would effect viewing as I haven't seen many 3D features presented in 2.35:1 aspect. Most directors seem to prefer 1.85:1 framing for 3D which makes sense for field of vision.

If it were me about to buy, I would probably go with a 16:9 screen with an electronic masking system than go for an anamorphic lens setup. It would probably come out cheaper than the lens rig and it's probably the most user friendly system. I think once we get through the novelty of 3D projection the next step the manufacturers like JVC and Sony will go for will be building the movable anamorphic lens into the projector chassis and then the whole constant height thing will really work well.

 

[Anonymous]

Thanks for the detailed help but can you explain to me what is meant by electronic masking system?

 

[Tom Moreno]

andytucker:Thanks for the detailed help but can you explain to me what is meant by electronic masking system?
Electronic masking is movable bits of black fabric on the screen that can block off areas of your 16:9 screen for viewing either 2.35:1 or 4:3 material. Using masking to view 2.35 material gives you a higher perceived contrast and image brightness because those black bars at the top and bottom of the image that are never "fully" black get completely blacked out by the fabric. An electronic system allows you to select different masking by remote and you can even set it to black out only the top bar for watching films that put subtitles in the lower bar. Some screens have masking systems built into them and there are also masking systems you can purchase to mount on top of an existing screen.

 

[Anonymous]

So if i watched say a football match in 16:9 on a 2:35.1 screen i guess i would have the black bars either side rather than top & bottom correct? Could this be streched via an X3 to fill the whole screen or would this look silly? Also would it cut off some of the top & bottom picture if i am watching a 16:9 program on a 2.35.1 screen or is the height of a 2:35.1 screen the same as a 16:9 screen?