Projectors and 1080i

[jtys17]

Hopefully this question isnt already posted, I spent some time searching and did not see it.

I currently own an older Sanyo PLC-XU50a. I got it a year ago from a personal friend and it was a good enough deal not to pass. I don't beleive it's considered a 'home theater' prjector but it has been doing a fine job.

In reading the instruction manual I found that it can support up to 1080i output.

If I connect my PS3 (using HDMI to DVI) I can get what appears to be a 1080i image. Games and movies looks great but I'm still a bit curious about whether the 1080i I'm seeing is true.

I'm wondering how an older projector can handle 1080i and whether I should sell this and look into buying a projector that is focused on home theater. Is the 1080i i'm seeing here going to comparable to what newer projectors are putting out? If it's marginal i'm not going to worry about it but I have a feeling it's significant.

Thanks,

Josh Tysinger

 

[avaserfi]

What most displays included projectors due is not actually display the an image exactly as it is sent to them. Instead the image is scaled, in your case from 1080i to 720p, to the native resolution of the display.

I don't know too much about this projector, but if you like the image then stick with it. If you are still curious go out to a couple AV shops and check ou the projectors you see on display.

If you are curious about the differences between 720p and 1080p (the two native resolutions of projectors) then check out this article. The need for 1080p compared to 720p is based not only on distance but also on screen size.

One thing that you did not mention was your screen. To get a quality picture from a projector you should be sending the image on to a material that is of the proper gain and design. If you don't have a screen yet check out carada screens or seymourav I have seen both companies screens and like them very much.

 

[no. 5]

As the projector is a LCD, I highly doubt that it is displaying anything as interlaced, and since its native resolution is 1024 x 768, I don't think it could do 1080 pixel for pixel.

Mind you I'm not a projector expert, so there is a possibility I'm wrong, but if you like how it looks, why spend more money?

 

[jtys17]

if you like how it looks, why spend more money?

I'm worried that I dont know what i'm missing.

Thanks for the advice so far. I might try to find an AV place in town to look at some other projectors.

My screen is currently a 76" wide InFocus manual pull-down. Nothing special but it serves the purpose for now.

 

[BMXTRIX]

Your projector...

http://www.projectorcentral.com/Sanyo-PLC-XU50.htm

Is a typical business class model 1024x768 (XGA) projector. If you are seeing a full screen image, than you are seeing 1024x768. If you feed it 1080i, then you are seeing - 1024x768, if you feed it 640x480 (VGA) - then you are SEEING 1024x768.

It is like if you only speak English and you understand French, Italian, and German (and English). If I speak to you in Frech, and you repeat it, what are you speaking?

That's right - English. It's all you know how to speak.

So, you first must translate it to your native resolution... I mean, language, then you can output what I sent to you. Probably have a bit of loss in quality.

Likewise, since this projector has a job of performing in the cheaper business office, you will get colors that aren't as rich, higher screen door effect, higher noise levels, and FAR worse contrast levels than a properly built 720p or 1080p projector designed for home theater use.

 

[bass addict]

The need for 1080p compared to 720p is based not only on distance but also on screen size.

Actually those 2 are directly related. To avoid SDE on LCD projectors (excluding the Panny's with SS), it is advised to sit 1.5 or greater screen widths away. This number will vary based on people's individual vision and preference but that is a good rule of thumb. 1080p will allow you to sit as close as you can be comfortable with without worrying about SDE.

I'm worried that I dont know what i'm missing

The problem with HT is there is always something bigger, better, more impressive out there. You will either go broke or insane chasing after it. If you are happy with the current image great. If not, then look into something you are happy with. I was more than happy with the image my TW700 threw until seeing the RS1. Now I'm depressed and trying to convince myself I need to spend the extra 4,000 to get one. That being said there are two major problems I see with that pj.

1) It is native 4:3. If you watch any movies at all that is a terrible aspect ratio. The 16:9's will obviously be letter boxed but you will get a much better experience going to a 16:9 native pj.

2) The on off contrast ratio is terrible. PJ's right now are putting out over 20x that amount and are still well short of the holy grail.

The nice thing about the pj world is, a 1,000 dollar pj nowadays will complete destroy a 5,000+ pj only a few years ago. If you can hold off I would wait until the new crop of pj's are released. With new offerings from JVC, Sony, Epson, Panasonic, and a host of others, the current crop of PJ's should have a significant price drop.

 

[BMXTRIX]

Actually those 2 are directly related. To avoid SDE on LCD projectors (excluding the Panny's with SS), it is advised to sit 1.5 or greater screen widths away. This number will vary based on people's individual vision and preference but that is a good rule of thumb. 1080p will allow you to sit as close as you can be comfortable with without worrying about SDE.

Viewing distance, while it may include SDE, is not primarily about SDE, but it is about the ability for humans to discern individual pixels. The goal is to sit at a distance that eliminates individual pixels visibility.

With 720p projectors, this is further than 1.5x screen width (not diagonal) and with 1080p projectors it is right about 1.5x screen width.

 

[bass addict]

Viewing distance, while it may include SDE, is not primarily about SDE, but it is about the ability for humans to discern individual pixels. The goal is to sit at a distance that eliminates individual pixels visibility.

What do you think SDE is? It's the ability for one to discern individual pixel structure, which is in direct correlation to distance from screen.

With 720p projectors, this is further than 1.5x screen width (not diagonal) and with 1080p projectors it is right about 1.5x screen width.

This isn't entirely accurate. First off with the SS in the Panasonic pj's you can sit as close as 1 screen width away before you start to notice SDE. I had an AE900. I am currently running an Epson TW700 and sit at almost exactly, 1.5 screen widths away and rarely am bothered by SDE (keep in mind the Epson is the 2nd sharpest 720p pj out there right behind the Sanyo Z5). If I slightly defocus the pj SDE pretty much disappears.

I have watched a movie on an RS1 at 1 screen width away with virtually zero SDE. It just isn't a factor for most everyone when you get into the 1080p realm.

 

[BMXTRIX]

What do you think SDE is? It's the ability for one to discern individual pixel structure, which is in direct correlation to distance from screen.

SDE is screen door effect, or more properly, inter-pixel gap. It is the space between pixels, and is a distance that is typically much smaller than the width/height of the pixel itself. With different technologies, inter-pixel gaps differ from each other, such as DLP, vs. LCD, vs. LCoS. In any of these cases, the pixels, for similar sized images, will be close to the same, while the inter-pixel gap will vary in size creating more, or less, visible SDE from the same distance.

But, because the pixels themselves are much larger than the gap between the pixels, this is the discernable feature that gets affected more by viewing distance and resolution.

So, while you are not incorrect about SDE being affected by viewing distance, visual acquity, as it relates to resolution, examines the pixels themselves, not the space between pixels.

This isn't entirely accurate. First off with the SS in the Panasonic pj's you can sit as close as 1 screen width away before you start to notice SDE. I had an AE900. I am currently running an Epson TW700 and sit at almost exactly, 1.5 screen widths away and rarely am bothered by SDE (keep in mind the Epson is the 2nd sharpest 720p pj out there right behind the Sanyo Z5). If I slightly defocus the pj SDE pretty much disappears.

I have watched a movie on an RS1 at 1 screen width away with virtually zero SDE. It just isn't a factor for most everyone when you get into the 1080p realm.

SDE is most definitely what you are speaking of, but visual acquity as it relates to visible pixel structure does not relate to SDE.

Smooth screen is often commented on because it actually can soften the appearance of the image as the very edges of pixels can be overlapped to elimate SDE. Yet, it is the separation of the pixels by inter-pixel gap, that helps maintain sharpness and definition in the image.

These individual pixels create an identifiable pixel structure that can be measured and directly plotted on a chart against standard human 20/20 vision.

Here is an article that explains it more fully with the graphs:
http://www.soundandvisionmag.com/hitech/1137/maxing-out-resolution.html

 

[jtys17]

Thanks for the posts. Everyone's advice has been very helpful; some however was over my head. BMXTRIX - thanks for explaining things so well for me..


Hypothetically, If I was to sell my current projector and purchase something more suited for HT - what are some recommendations for a $700-800 range machine.

I primarily use mine for movies and games - source being a Playstation 3. Most games being 720p, blueray's @ 1080p, upscaled dvd's etc.

I'm in the process of buying a new home so the distance thrown is hard to estimate, but I can't imagine anything over 20' or so. I might consider a screen around 100" but probably not too much larger.

Thanks again for the help so far.

 

[jtys17]

From what I've seen so far this is my best bet for under $1000-

Optoma HD70

MITSUBISHI HC1500

Mitsubishi HD1000U

 

[bass addict]

I'd try and demo a few pj's so you can get a feel for LCD, LCOS, DLP, etc. LCD is going to have the most flexibility so I'd recommend them. If 20' might be in the picture that is going to limit a lot of pj's. A good bet would be the AE900. Check this site out. It gives a complete throw range breakdown.

http://projectorcentral.com/projection-calculator-pro.cfm

 

[BMXTRIX]

All three of the projectors you have listed have good ratings and will provide a good home theater experience. The downside to all of them is that they have a pretty significant lens offset which basically will force you to place them about 2 feet above the top of your screen for best image quality.

If this works for you (8'+ ceilings) then that is great. If it doesn't, then it will run a bit more to go with a projector like the Panny AX100 which will give you the lens shift you need to get the best image in almost any environment.

FYI: I have heard slightly stronger support for the HD1000 over the HD70. But, I think it is a very minor quality difference between these two projectors.

NOTE: 1080p support is almost unneccessary on a 720p projector like these are. They should mainly support standard HD formats such as 720p and 1080i for optimal performance.