Projector with Anamorphic Image

Q Acoustics M20 HD wireless music system
S

soundofmusic

New Member
Joined
Aug 14, 2007
Messages
583
Points
0
Location
coimbatore
Hello,
I am on a lookout for a Projector which has the anamorphic Image. I read somewhere in the forum that the Mitsubishi HC 4000 and Optoma 3D 33 has this function. What size projector screen should be used for anomorphic image. A clip in the Youtube says 2.35 to 1.78 is the correct size for anamorphic image. So if I buy this size screen and buy the HC 4000 or optoma 33, will i get the anamorphic image ie., with out black bars on the top, bottom and the sides.

TIA
Best Regards
 
i have heard of anamorphic lens to be attached to the projector somewhere in HFV, keep a search.....
 
yes there are anamorphic lens available, but the HC 4000 and the HD33 have these facility ( thats what i read somewhere in the forum ) can any one clarify this.

TIA
 
Anamorphic Option:
All the anamorphic options constitute of two things.
  1. Anamorphic Lens
  2. Doing a vertical stretch on 2.35 aspect ratio picture so that it completely fills the 16:9 image. Anamorphic lens then expands it horizontally, giving the 2.35 aspect ratio picture.

You need both to get 2.35 image without vertical bars. When projectors mention about anamorphic option, they mean that it does have the second element of vertical stretch. The projector will do the vertical stretch and you still need anamorphic lens to stretch it horizontally.

Early days, not all projectors did not had this option. We had to use an external video processor to do the vertical stretch.

There is another method - Zooming. Some projectors like Panasonic have this option. It zooms to completely fill 2.35 screen. The bars above and below the screen still exist but end users can mask it.
 
Anamorphic Lens price is minimum 2.5 laks. Why you want to use such costly lens with low cost projector ?
 
arindamcc said:
Anamorphic Lens price is minimum 2.5 laks. Why you want to use such costly lens with low cost projector ?
Click to expand...

Anamorphic lenses are not so expensive as you are telling. There is one VFM and a well regarded Aussiemorphic lens from Cavx costs ~1500$ (i think its MK3 with 3 element lens) and their 5 element lens costs ~2600$ max. Moreover eBay is another source where we can get similar lenses very cheap. Moreover there will not be a day n night difference b/n a high end pj and a decent pj like Pana4000, so there is no distinction like low cost pj and a high end pj. But the viewing pleasure it gives even on a basic pj will be tremendous. This will be in my first priority list once I am going for a proper dedicated HT room. Moreover the option for vertical stretch is available in projectors like Optoma HD20 (LetterBox)

letterboxed_image1.jpg


to

letterboxed_image_stretched1.jpg
using Vertical stretch and the image geometry will be maintained by the lens:

letterboxed_image_expanded.jpg
 
Last edited:
A poor man's 2.35:1 projection can be a vertical stretch done using LetterBox and horizontal stretch using MPC from an HTPC.
 
cmsajith said:
Anamorphic lenses are not so expensive as you are telling. There is one VFM and a well regarded Aussiemorphic lens from Cavx costs ~1500$ (i think its MK3 with 3 element lens) and their 5 element lens costs ~2600$ max. Moreover eBay is another source where we can get similar lenses very cheap. Moreover there will not be a day n night difference b/n a high end pj and a decent pj like Pana4000, so there is no distinction like low cost pj and a high end pj. But the viewing pleasure it gives even on a basic pj will be tremendous. This will be in my first priority list once I am going for a proper dedicated HT room. Moreover the option for vertical stretch is available in projectors like Optoma HD20 (LetterBox)
...
Click to expand...

You can also build your own using a pair of prisms. Many have done that.
 
yrk1969 said:
You can also build your own using a pair of prisms. Many have done that.
Click to expand...

In general, adding a prism lens means adding some more optical surfaces in the light path. Each Prism has two sides that light passes through. For any lens, there are at least two prisms. That's total 4 surfaces. When light passes through these 4 surfaces, the picture becomes quite blurry. Also, the prisms need to be optically coated otherwise there will be reflections within the prism which reduces the contrast a lot. But that's still okay. For DIY prisms, the main issue is Chroma Aberration. When a light passes through a prism, it does breakdown and gives a little rainbow effect. It's unavoidable. The commercial lenses do have a CA correction element at the inlet and outlet of the lens which corrects it to almost 95% or may be more. But it still stays there and you can see it. For DIY, without the correction elements, its all over there to see yourself. I have been there, done that.

Anyhow, if someone wants to dwell in it, then atleast do this.
  • Get big prisms. The ones I had were 4" x 7". When the picture goes through lens, it becomes quite big as it is leaving the lens.
  • Make sure the Prisms are at least optical grade, BK7 glass.
  • See if you can get the Anti-reflective coating done on those. This is minimum.
  • Mark the edges of the prism with black velvet. carefully glue it. If not comfortable, then atleast use the black marker to darken the edges.
  • Line up the inside of lens housing with very dark, non-reflective velvet.

There are lots of sites giving info on it. But from my opinion, save the hassle and invest in a used, aftermarket lens. In the long run, you will save money. :) DIY is a fun project, but it ends there. It degrades the picture quite a bit, to the point you are better off zooming to fill the screen.
 
manoj.p said:
In general, adding a prism lens means adding some more optical surfaces in the light path. Each Prism has two sides that light passes through. For any lens, there are at least two prisms. That's total 4 surfaces. When light passes through these 4 surfaces, the picture becomes quite blurry. Also, the prisms need to be optically coated otherwise there will be reflections within the prism which reduces the contrast a lot. But that's still okay. For DIY prisms, the main issue is Chroma Aberration. When a light passes through a prism, it does breakdown and gives a little rainbow effect. It's unavoidable. The commercial lenses do have a CA correction element at the inlet and outlet of the lens which corrects it to almost 95% or may be more. But it still stays there and you can see it. For DIY, without the correction elements, its all over there to see yourself. I have been there, done that.

Anyhow, if someone wants to dwell in it, then atleast do this.
  • Get big prisms. The ones I had were 4" x 7". When the picture goes through lens, it becomes quite big as it is leaving the lens.
  • Make sure the Prisms are at least optical grade, BK7 glass.
  • See if you can get the Anti-reflective coating done on those. This is minimum.
  • Mark the edges of the prism with black velvet. carefully glue it. If not comfortable, then atleast use the black marker to darken the edges.
  • Line up the inside of lens housing with very dark, non-reflective velvet.

There are lots of sites giving info on it. But from my opinion, save the hassle and invest in a used, aftermarket lens. In the long run, you will save money. :) DIY is a fun project, but it ends there. It degrades the picture quite a bit, to the point you are better off zooming to fill the screen.
Click to expand...


Yes, the DIY lens in a budget with acceptable PQ is almost impossible. FOr DIY, the options are the trophy vendors for glass prisms or liquid filled prisms, but to reduce the chromatic is very difficult and expensive too. Its the same with the antireflective coating. The aussiemorphic lens from Cavx was started as a diy project and it went through a lot of revisions and the MK3/MK5 are one of the best quality lens from them and is accepted very well and its not too expensive also.
Another common issue is the pin cushion distortion and it can be addressed by a curved screen (also this will give the exact feel of a theater)
http://www.dnp-screens.com/DNP08/Products/Front-projection/FAQ/Why-curved-screens-for-Home-Entertainment.aspx
The curvewd screen can be a DIY option
@Manoj, are you using a curved screen? How bad is the pin cushion in Panamorph lens?

As I told another option is the used lens from eBay or similar stores.
 
Last edited:
Sajith,

I have moved away from the Anamorphic/2.35 setup since Feb this year. Went back to 16:9.

As you know, I had the laminate as screen, glued to the wood frame. But the frame was quite big and long, so could approximately curve the screen little bit. At both left and right, I pulled the screen along with frame out, approx 5" on both sides. That made the screen curved a little bit. There was still some pincushion left which I masked it with velvet. Without the tilt, the pincushion was approx 1.5". Meaning the height at left/right ends was 1.5" more than height at the center of the screen. My screen was 138" wide, given the size I think that 1.5" pincushion was not that big at all.

More to keep in mind - Pincushion does depend on few factors. Long throw distance between projector and screen, mounting the lens very close to the projector, smaller screen size etc will lead to smaller pincushion. We have to do best in setting up within our limitations.

New lens cost quite a bit. I think used lens provides a lot of value. Too bad, I did not know the interest in India. I sold my lens for $1200 here. Somebody in India could have benefited with that price.
 
Thank you sajith and Manoj, If its only the geometry correction, doesnt its quality reduce? is it like stretching the small image to a larger size?

Cheers
 
Every anamorphic lens that you put infront of the projector will indeed reduce the picture quality. It goes down with respect to contrast, chroma aberration, sometimes there are lens light scatter, pincushion effect etc. Picture becomes bit blurry because of this. But some users think it has the same effect as Cinema theaters and give the picture that film kind of look. Also pincushion also makes the picture look like theater cinemascope picture - Sides bigger than the center.

High quality lenses like Panamorph and ISCO-3 (this is considered top lens) have about 96~98% contrast of the projector through the lens. Hope this gives you some idea.
 
HiFiMART.com Offers & Deals on WhatsApp
Join WhatsApp group to get HiFiMART.com Offers & Deals delivered to your smartphone!

Similar threads

S
Is it crazy to use a projector with a Fire TV stick?
Replies
5
Views
8K
sudokpr
S
K
Need Help with selecting a Projector Screen
Replies
14
Views
1K
k_vijay12
K
Athulan
Xgimi Horizon Pro / Horizon - Auto Keystone Feature
Replies
4
Views
3K
RaaR
R
NewBee2020
AUN A6Key Projector - Is it good for starters in a low cost budget?
Replies
16
Views
5K
Srinivasa Rao
Srinivasa Rao
A
Optoma Unveils P1 - 4K Ultra Short Throw Laser Projector with Integrated Soundbar
Replies
0
Views
930
Arjun4
A
Back
Top