[Mark Techer]

Correct. There are two basic modes you need to do this -Vertical Stretch and Horizontal Squeeze. Then you can watch both 1.78:1 and 2.37:1 with the lens in place and switch ARs with the remote of the projector...

Mark

 

[Sonnie]

With all of the projectors I have owned... I didn't have to switch AR with the remote... it was automatic. Would this be something different, or are you familiar with this projector?

 

[Sonnie]

I know I am full of questions, but this has my interest indeed.

Are you familiar with Home Theater Brothers lens that is $610 shipped?

What do they mean by: Best results are achieved with throw ratios above 1.7?

Thanks for all the help!

 

[Prof.]

The HTB lens is the one I suggested at $600.00..
By all accounts, It's quite a good lens...

The TR they mentioned is the recommended minimum TR to keep pincushion to a minimum..
You can have a slightly lower TR and still be able to use the lens, but you will have a little bit more pincushion effect..

 

[Sonnie]

What is 1.7 in relation to though?

Projector needs to be mounted 1.7 times the width of image?

120" width... projector needs to be mounted at least 17' from screen?

 

[Prof.]

That is correct..:T

 

[Prof.]

I should have mentioned that the image width refers to the width of a !6:9 image..

 

[Sonnie]

Well... even if it was for the 2.35:1 image of my proposed 120-122" screen, which would be about 17'... that is not a problem. Most likely I will end up being at 17' 6" for a zoom of 1:1 at 16:9.

I am still a little confused about what has to be done on the HC6500 in order to switch between formats, if anything. Hopefully it is just a push of a button, or maybe nothing. I don't want to have to focus the image every time I change the format... or adjust lens shift. I am assuming I will have CIH, but not sure. I probably just need to research the projector features more and find someone who owns one and is using a lens. :dontknow:

 

[Mark Techer]

When you said the AR is Automatically changed, I have to assume that you are referring to 16:9 screens where the Scope AR is simply letter boxed. CIH means that there are no black bars and because the image is 33% wider than a 16:9 image of the same height, you do have to select a different opperating mode. When using a lens on the Panny projectors, you switch between 4 x 3 and Zoom1. You do not use the 16:9 mode with the lens in place. Yes I am familiar with these projectors.

Your TR is found by dividing the native 16:9 image width into the distance between the screen surface and the projector's lens. Therefore, if your Scope screen is 118" wide, then the 16:9 portion will be 88.5". You then can times 88.5 by the TR to find the mounting distance you need, or you divide that into the distance from the screen to the projector's lens to work out the TR.

88.5 x 1.7 = 150.45". I personally would be looking to extend the TR to at least 2.0:1 to reduce the pincushion and even help reduce some of the CA that you might see from a 2 prisms (2 element) lens. The CA reduction is due to lessening the angles of the beam. CA will always be visible in such a lens, but if you can reduce it, then you should make the effort to do so...

Mark

 

[Sonnie]

When you said the AR is Automatically changed, I have to assume that you are referring to 16:9 screens where the Scope AR is simply letter boxed.

Yes... if I insert a 16:9 AR DVD, it shows 16:9... if I insert a 2.35:1 or 2.40:1 DVD, it has black bars on top and bottom. If I insert a 4:3 DVD, it has black bars on both sides. No buttons are required to push... no focus adjustment... no lens shifting... just insert and press play.

CIH means that there are no black bars and because the image is 33% wider than a 16:9 image of the same height, you do have to select a different opperating mode. When using a lens on the Panny projectors, you switch between 4 x 3 and Zoom1.

So... does the anamorphic lens give me CIH?

You do not use the 16:9 mode with the lens in place.

So why does Mitsubishi state that you do not have to remove the lens to view 16:9 images?

From Mitsubishi:

The HC6500 has Mitsubishi's dual anamorphic modes, which allow the user to forego the articulated track usually paired with an anamorphic lens. Instead, the HC6500 scales all content for proper display through an anamorphic lens, and the lens remains deployed at all times.

Your TR is found by dividing the native 16:9 image width into the distance between the screen surface and the projector's lens. Therefore, if your Scope screen is 118" wide, then the 16:9 portion will be 88.5". You then can times 88.5 by the TR to find the mounting distance you need, or you divide that into the distance from the screen to the projector's lens to work out the TR.

88.5 x 1.7 = 150.45". I personally would be looking to extend the TR to at least 2.0:1 to reduce the pincushion and even help reduce some of the CA that you might see from a 2 prisms (2 element) lens. The CA reduction is due to lessening the angles of the beam. CA will always be visible in such a lens, but if you can reduce it, then you should make the effort to do so...

So... if I want my 16:9 AR image to be 102" wide, the projector should preferably be mounted at 204" (or 17'). So my 17.6' is looking good.

What is CA? I thought the image with this lens setup is supposed to be much better than without it. It sounds like it might be hindered in some way or another.

 

[Mark Techer]

Yes... if I insert a 16:9 AR DVD, it shows 16:9... if I insert a 2.35:1 or 2.40:1 DVD, it has black bars on top and bottom. If I insert a 4:3 DVD, it has black bars on both sides. No buttons are required to push... no focus adjustment... no lens shifting... just insert and press play.

Then your player was also doing a horizontal squeeze to allow you to see 4 x 3 material with side pillars and not have you change to the 4 x 3 mode on the projector. My BD player does that which is a good thing...

So... does the anamorphic lens give me CIH?

The only true way to have Constant Image Height is to use an anamorphic lens...

So... if I want my 16:9 AR image to be 102" wide, the projector should preferably be mounted at 204" (or 17'). So my 17.6' is looking good.

With CIH the longer the throw the better...

What is CA? I thought the image with this lens setup is supposed to be much better than without it. It sounds like it might be hindered in some way or another.

Lens pending, the image can be better. CA is Chromatic Abberations. There is a thread on it in this forum. My new lens is corrected for CA, so does not show it. This is also a reason why most anamorohpic lenses are expensive. CA and focual correction come at a cost. The $600 lens you looking at only has two prisms and they are nothing more than trophies at that, so you will get what you pay for. There is allot to good optics and whilst prisms are a means to an end, there is much work needed to make them work well...

Mark

 

[Sonnie]

Sounds like I might be better off waiting until I can afford a good lens. I do not want to do anything to degrade a good image. I lived with the black bars on top and bottom of the 2.35.1 images forever... not that big of a deal. No sense in paying $600 to make the image fill the screen and it be worse quality. :huh:

Here is the info on the HC6500. It doesn't make sense to me. The last two columns are for anamorphic lens. I looks like you would select anamorphic1 for 2.35:1 AR images and anamorphic2 for 4:3 or 16:9, but in the examples that are highlighted in each column (bottom right corner squares), both look like they are squeezed up.

 

[Sonnie]

There also looks like there is an "Auto" setting, but not sure if it could be used or not. It is not really clear for anamorphic lens.

 

[Sonnie]

I think I understand now... the projector does the squeezing... then the anamorphic lens stretches it back out.

Rodny called Mitsubishi today and they could even answer questions about the features of the unit. :loco:

It is still a question as to whether or not the lens shift, zoom or focus have to be used with the HC6500... or simply select A1 for 2.35:1 and A2 for 4:3 or 16:9.

 

[Mark Techer]

So I would use the cash that you had set aside for a new projector and be looking to buy a good lens. The right decision here means that you never need to upgrade that part again.

Yes you have the idea, scaling plus optics.

One of the ideas towards leaving the lens in place all the time is that you don't have to re-focus and your calibration settings remain the same as well.

Then AR changes are as simple as pushing a button on the remote...

Mark

 

[Sonnie]

That's sounding good... :T

At this point, I have went extra on speakers, which was not initially planned, so I don't have any extra above about $2500 to put into a projector setup. $600 for the lens is pretty much it for now.

If I plan on doing a 2.37:1 or 2.40:1 screen right now, then I am going to need to do a lens, otherwise I have to readjust each time I have different aspect ratio's or either have wasted screen space on every aspect ratio. Neither of those sound good.

I also do not believe I will ever be ready to spend $1500 to $2000 on a lens... not in this lifetime anyway. If they ever come down to less than $1000, then we might consider it.

 

[Rodny Alvarez]

This is from audioholics.......

Viewing widescreen 2.35:1 aspect ratio films is simple and easy with both new projectors; each provides Anamorphic Lens Modes 1 and 2 support. In the past, users needed an expensive lens railing or tracking apparatus to install or remove an anamorphic lens, depending on the desired 2.35:1 or 16:9 film aspect ratios. With the HC7000 and HC6500 users can now simply position an anamorphic lens permanently in front of the projector lens and select the appropriate Anamorphic Mode 1 or Mode 2, either 2.35:1 or 16:9 aspect ratios, for the corresponding movie format. It’s a simple and economical design that saves time and effort while providing the ultimate home theater viewing experience.

this one from pjcentral....

Dual Mode Anamorphic Stretch. First introduced on the HC5500, Mitsubishi's Dual Mode Anamorphic Stretch allows the viewer to install an anamorphic lens permanently in front of the projector, rather than on a moving track. When showing 16:9 films and video, the projector compresses the signal horizontally such that it passes through the lens and is stretched back to the proper 16:9. Since motorized tracks for anamorphic lenses typically cost quite a bit, this is a helpful feature that can save you money.


here from mitsubishi.....

http://global.mitsubishielectric.com/bu/projectors/products/home/hc6500_features.html

 

[Sonnie]

I think the question now is really whether or not we can find a lens for less than $1000, (ideally around that $600 mark) that will not degrade the image to a point that would be worse than what we could get by purchasing the Panasonic 3000 and simply zooming the image.

Here's my point. If I can zoom the Panasonic image (which the zoom would only be 1.4:1 at the planned throw distance on 2.35:1), and that zoomed image looks as good as the $600 lens with CA on the HC6500, it seems more reasonable to just buy the Panasonic 3000 and be done with it. That way there is no fooling around with the lens.

 

[hddummy]

Be aware that if you use the Mitsubishi method, when you watch 16:9, the projector has to scale the image down to a ~1440x1080 image so the lens can stretch it back to the correct size. You are literally eliminating 25% of the image information just for convenience.

For any anamorphic lens option, the projector has to digitally stretch 2.35 material 33% vertically. The quality of the result will depend on the scaling ability of the projector. People keep saying you get 1:1, but that is not correct. What they mean is that you are utilizing the full image panel in the projector, but is that really a good thing? The portion of a 16:9 image used by a 2.35 format is 815 pixels high, so stretching it out to 1080 is not 1:1, it's 1.33:1. In my opinion any time you do digital processing on an image when it is not necessary only adds risk of making it worse. That on top of the fact that you introduce pincushion distortion and chormatic abberations makes the lens option a two thumbs down in my opinion.

The biggest detriment to the zooming method is that you are using 75% of the image panel, and therefore 75% available light, on a screen that has 33% more area than a 16:9. With a lens, you use 100% of the available light on a 33% larger screen. The PT-AE3000, however, is a rather bright projector and can still provide enough light output at that screen size. This is especially true in a light controlled room. In fact, you might even want to turn down the lamp brightness in 16:9 mode to provide the same on screen light density as you get in 2.35 mode. You would even extend the lamp life a little if you did.

Lastly, since you are zooming, each pixel does infact occupy more screen area in 2.35 zoomed than 16:9 regular. However, if you do the math for a 50" high screen, a 2.35 zoomed pixel is only .06 inches wide and a 16:9 pixel .046 inches wide. When you are sitting 10 feet from a screen, i challenge anyone to tell me the difference between the two. Do a little research into human eye acuity and you'll find that you need to actually sit 6 feet from the screen before a person with 20:20 vision could discern two adjacent pixels at that size.

Conclusion....buy the Panasonic, set it up for zooming and enjoy. If you honestly think you can gain by adding a lens...you can still do that later down the road.

 

[Sonnie]

Hmmm.... our first row seating will cause our eyes to be about 12' from the screen.

As I mentioned earlier... with our last projector (Panasonic 2000) we were zooming the 16:9 image at 1.6:1... never thought anything about it... image looked stellar to us sitting at 10-11' back.

With the 3000, if we go with the maximum throw distance of 19'7", the 16:9 image would zoom to 1.06:1, which should leaps better than the 1.6:1 image we had with the 2000. The 2.35:1 image will be zoomed 1.42:1.