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Optoma HD70. The new budget king. - Page 2

post #31 of 2476
Quote:
Originally Posted by HeadRusch View Post

Offset is the position of the projected image relative to the centerline of the lens.
...
But it also means that those of us who have our PJ's hung inverted from the ceiling have to have very tall ceilings the higher the offset percentage gets.

Got it. Thanks.

I plan on having a ceiling mounted PJ in the near future and am trying to get educated. Can you point me towards a calculator for checking things like this? I've seen the one at projector central, but it looks like that deals only with throw and screen size. I was thinking of getting the HD72, and used the .xls calculator found on this forum (thanks), and it looks like it would work ok.

So you want a PJ that will work in your setup without having to adjust the image at all to minimize distortion, right? I'm glad I learned this - my ceiling will be <7'
post #32 of 2476
The offset information is normally only found in the owner's manual (which can be downloaded from the manufacturer's web site, usually). Projection calculators only cover screen dimensions and distance to the screen, etc. (and not offset).

With only a 7' (max) ceiling height, you're probably stuck with shelf mounting (with any decent sized screen - 92" to at least 106", the bigger the better ).
post #33 of 2476
Can the offset be figured out from the numbers nightfly posted in post #23?
post #34 of 2476
According to the review here http://www.homecinema-fr.com/forum/v...php?t=29829465 .He says offset is approx 30 %. You'll have to translate the page it is in french.
post #35 of 2476
I hope it turns out to be better than the HC3000U, because it can be had for less from an authorzied dealer right now. So, hopefuly it'll have a nice street price soon.
post #36 of 2476
I found a user manual on the asia site: http://asia.optoma.com/Service/Produ..._Download.aspx

On page 16 of the manual it shows the angle offset, but I'm not smart enought to figure it out. Many somebody can help me.
post #37 of 2476
The offset is:

H' = L x tan(8.13 deg)

where L is the projection distance - I got about 28 inches of drop for a 143" diagonal image, at a 5 meter (196.5") throw...
post #38 of 2476
30%..cool, then its just like the H31..or awfully close.

I'd still have to keystone in my super low ceiling environment but I've not seen any keystone image degradation on my current setup (H31), I'm hoping that trend would continue with the HD70.
post #39 of 2476
Projecterguy1 thanks! This will be perfect for me.
post #40 of 2476
Quote:
Originally Posted by MTyson View Post

I hope it turns out to be better than the HC3000U, because it can be had for less from an authorzied dealer right now. So, hopefuly it'll have a nice street price soon.

I'd like to know where you can get the HC3000U for less than 999! Please PM me.
post #41 of 2476
Just downloaded the manuals from my projector (EP719), the H27 and H30 and the HD70. From what I can gleam at a quick visual inspection the offsets are all very similar if not the same. Unfortunately, the ceiling mount is different - different size screws on the bottom and a different shape plate would need to be used. I was comparing it to the H27 because others have remarked how similiar they are in body shape. $50 for a new ceiling mount on eBay adds up as often as I upgrade projectors.

I need a little help, guys, doing the math on the offset. Maybe point me to a forum that explains it all? I have the ceiling mount, but never used it yet because I move my current pj back and forth - with this next purchase, I'll have one fixed at work (using this current ceiling mount, fixed for teaching) and likely the HD70 (price/performance looks unbeatable) for home. Ceiling is 10'7" and screen height is 4' and the bottom is 4' up off the ground (yes I know it's high, it has to be above my entertainment center, we deal with it just fine) leaving 2'7" from the top of the screen to the ceiling. Is this a problem? Help me run the numbers - teach me how and I can run 'em.. I hope.
post #42 of 2476
Quote:
Originally Posted by HeadRusch View Post

I'd still have to keystone in my super low ceiling environment but I've not seen any keystone image degradation on my current setup (H31), I'm hoping that trend would continue with the HD70.

How low is your ceiling? How large is your screen? How far from floor/ceiling is the image?
Thanks
post #43 of 2476
Quote:
Originally Posted by nightfly13 View Post

I need a little help, guys, doing the math on the offset. Maybe point me to a forum that explains it all? I have the ceiling mount, but never used it yet because I move my current pj back and forth - with this next purchase, I'll have one fixed at work (using this current ceiling mount, fixed for teaching) and likely the HD70 (price/performance looks unbeatable) for home. Ceiling is 10'7" and screen height is 4' and the bottom is 4' up off the ground (yes I know it's high, it has to be above my entertainment center, we deal with it just fine) leaving 2'7" from the top of the screen to the ceiling. Is this a problem? Help me run the numbers - teach me how and I can run 'em.. I hope.


For a 4' high screen (~100" diagonal), the throw would be about 79", so the offset is roughly...

H' = 79 x tan (8.13) = 79 x 0.142855 = 11.3"
post #44 of 2476
Ok! Now, interpret the meaning of that for me... 11.3" from the center of my lens to the bottom line of the screen? Also, I know this puppy only has a 1:1.2 zoom, but would that effect the offset too?

When you calculate 'throw' (79" = 6'7") doesn't the 2 meter projection distance on the pdf suggest the min/max 16:9 screen size from that distance be 47-57"? I've been thinking (and wiring!) that I'll have a roughly 13' throw to achieve the 100" diagnal image.. which part am I calculating wrong? Thanks for being patient with me.
post #45 of 2476
Bad ass!

Finally an X1 replacement!

Waiting eagerly to hear what kind of scaler/deinterlacer it has in it. Always liked the Optoma product line.
post #46 of 2476
Anyone buying this as soon as it comes out? I am very interested to hear a review and know the real offset and throw distance.
post #47 of 2476
I think alot of people will be keeping their eye on a 720p DLP for 1K

And if a 720p DLP can be had between 1 and 2K, that leads me to believe 1080p PJ's will be falling under the 5k barrier sooner rather than later...
post #48 of 2476
There is a projection distance calculator on the optoma uk site. Looks like this won't work for me. I only have 9 feet from the projector to the screen and will barely be able to get 60 wide picture at full zoom. I may have to go with the hd72.
post #49 of 2476
On the press release of the HD70 it says:

Quote:
New purpose designed 5 speed, 7 segment colour wheel technology.

What is the meaning of "5 speed" ?. Are they talking about the speed of the colorwheel ?, how could it be 5X when the speed of the HD72 is 4X ?.
post #50 of 2476
Quote:
Originally Posted by Jones_Rush View Post

how could it be 5X when the speed of the HD72 is 4X ?.

By making it faster.
post #51 of 2476
lol, I just thought they went for a budget design with the HD70, so the usage of a faster colorwheel is confusing...
post #52 of 2476
Yeah I guess the point to bear in mind is that the HD70, while a cheaper model with a different demographic in mind, is a whole generation newer than the HD72 (which is, correct me if I'm wrong) 8-9 months old. In this world, things get better and cheaper, fast That's not to say that the HD70 is going to be 'better' than the HD72 (likely not) but it might have some features that are preferable, since it's a 'whole' generation newer.
post #53 of 2476
If it doesn't going to have any major flaw in pic quality/build quality, it is going to dominate the budget pj market. I mean, without rebates, the next 720p offer (whether LCD or DLP), street for ~70% more $$$...

If the pic quality of the HD70 is anything near the HD72, imo the HD72 will soon be discontinued and replaced by a newer model, because it's not competitive anymore.
post #54 of 2476
Wow, that's an amazing price! I'm about up on my H-31's bulb, think I'll be picking up this bad boy!
post #55 of 2476
There seems to be a difference in the throw calculator on the uk site and the one in the manual. The uk site says for a 85.77 wide image I need a throw of 4.03 to 4.13 meters, but in the manual it says I can get the same size image from 3 meters. Kind of a big difference.
post #56 of 2476
There has got to be some compromise to get the price down.
Dont get too excited. Wait till you see the cheapo PJ's

Except Infocus no one mentiones the actual specs. It is not
going to be 1000 lumens or 4000 CR after proper calibration.

Needless to say that there is not going to be any quality
control on all these cheapo PJ's.
post #57 of 2476
Well Mupi, I feel that's a bit of a false dichotomy to say that it's not going to meet the specs because it's a low-price unit. All projectors (with the possible exception of InFocus) play this same game, so you can in fact use the specs as something of a reference point - whether it's a cheap unit or not - as long as you bear in mind that the real-world optimized performance will be down across the board. I have a 2500:1 CR Optoma multimedia projector that I'm sure 'cheats' similarly in the spec reading, does that mean that this one won't have significantly better contrast? Of course it will. Also to assume that the same compnay does no quality control on the bottom end of their product line also seems unduely critical. Optoma's lower end HT PJs have received rave reviews from what I've seen, don't knock a model no one's even seen yet.
post #58 of 2476
Ok, that site that has the preorder available lists the MSRP at $1499. Why on earth would they drop the price THAT drastically from the MSRP? That's just very odd to drop a third of its total price before it's even released.

Strange, but exciting times.
post #59 of 2476
Quote:
Originally Posted by FlyFred View Post

How low is your ceiling? How large is your screen? How far from floor/ceiling is the image?
Thanks

My ceiling is about 6' 6" from floor to the ceiling tiles.

Right now my PJ is mounted inverted and 1/2 the projector is up into the space where one of the ceiling tiles was located. The lens is almost flush with the ceiling tiles (so 6' 6" off the ground, inverted).

The projector is then tilted up a bit towards the ceiling tiles, and I use keystone correction to square up the image on my 106" screen. When people look at it they go "Isn't that projecting..uh, onto the ceiling?". Then I explain about the image offset. It looks, physically, like the lens is pointing up towards the ceiling at a shallow angle.

When projecting, the top of the image is about 5" below the ceiling tiles, squared up with my screen. I think its like 24" off the floor for the bottom of the image. About as big as I can go with a 16:9 screen with this ceiling height.

No problems at all, tho I do have to use keystoning. Some people hate it, others, like me, can't see any noticible difference in image quality..but I'm guessing that varies from PJ to PJ.
post #60 of 2476
Which chip is this... HD2?
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