CurtPalme.com Home Theater Forum

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

hello all, i picked up a g70 today. im pretty pumped about upgrading from my 1252 but will need some help. i suppose the first step is to give the set a good eval. the outside has its share of wear and tear but the inside is nice and clean. there was some dust but very little. not even much on the fan blades. i havent taken the lenses off but i only see slight wear on the green tube and its nice and big. i do however see an artifact in the green and red tube. with contrast turned down and brightness turned up theres a wierd distortion line on the blue and a "blob" in the red. any ideas? the set was at 50 and 80 brightness/contrast when i picked it up. do you guys need pics to start with the artifacts?

Zebu Fellenz · Joined: 21 Dec 2006 Posts: 2548 Location: Phelps, New York

The blob on the red may be a sunburned C-element, hard to say without a picture though.

**ecrabb** · Posted: Wed Feb 16, 2011 11:21 pm Post subject:

Cool!!!

Yeah, first thing to do will be removing the lenses and using a flashlight to do a good inspection of the tube faces and c-elements. If it's nothing optical or on the tube faces, then we can start talking about electronics.

I think 50/80 was default bright/contrast.

SC

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

WHats the c element? easy fix? pics coming.

**Curt Palme** · Posted: Thu Feb 17, 2011 1:35 am Post subject:

I've got those elements if you need them.

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

heres the blob on the red lens. cant see it on projected image, course that image is now on a rough, pink insulated garage door wall! couldnt see the smear in the green pic. how much do these elements run curt? i can tell already that im digging the extra light output! i noticed in the menu what looks like the ability to connect component video to this pj? is that right?

**ecrabb** · Posted: Thu Feb 17, 2011 3:20 am Post subject:

That does look kind of weird... Could definitely be a melted c-element. It probably wouldn't be too noticeable on-screen - until you got your focus good, that is.

Get those lenses taken off and look at the tube faces and c-elements! The c-elements are on the projector where the cooling chamber glass was on your 12xx. Remove the lenses by taking the Phillips screws out at the 45-degree positions - just like the 12xx...

Here's an image I just googled...

Do NOT remove or loosen the allen or torx screws holding that round plate on in the image above.

SC

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

i hope to pull the lenses tomorrow, ill post some pics of what i find.

**ecrabb** · Posted: Thu Feb 17, 2011 3:25 am Post subject:

Oh, and yes - the G70 will accept HD (YPbPr) component.

SC

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

what would be better, rgbhv or component? i have a simple setup, a pc, vga to rgbhv, and thats about it. Santa did bring me a nice Denon networked a/v receiver last year. its a shame not to use the video switching in it. i used the pc purely for the benefit of scaling SD dvd's. would i be better served to now send dvd video via component through denon or keep pc? the denon upscales but only to default values like 720, 1080 ect. nothing in between.

Zebu Fellenz · Joined: 21 Dec 2006 Posts: 2548 Location: Phelps, New York

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

ok, i removed the lens's to look at the tubes. light wear on the green, very, very light wear on the blue, and i cant see any wear on the red. the "blob" and smear is not on the lens but once removed, what would be in front of the tube face. in the reflection on this concave surface i can see the physical presence of the blob. like its melted. is this the c element? looks like it would kill the picture but how visible would this be?

blue

green

red

**Curt Palme** · Posted: Thu Feb 17, 2011 9:58 pm Post subject:

You will totally notice this blob. What's happened is somehow the lenses were pointed towards the sun. When installed, the lenses act like a magnifying glass on paper, and the sun melted the lens. This can happen within 10-20 seconds, so it doesn't take much.

You need to take the tube out, put it between your knees, and take that metal ring around the C element off. (that concave element is the C element.). There's about a pint of glycol/cooling fluid behind that C element, that's why you want the tube completely upright so it doesn't spill. Extract the old C element and put in the new, and reassemble.

That's how I do it (wearing old jeans, as some glycol will always spill). You can also drain the glycol first, but it's faster to do it my way.

I've got those C elements at $75 plus shipping.

Cheers!

**ecrabb** · Posted: Thu Feb 17, 2011 10:55 pm Post subject:

Too bad about the melted c-element, but other than that, the machine looks pretty damn nice! Sweet!

Melted c-element sucks, but it's a lot better than a burnt tube. $75 and you're off to the races!

SC

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

is that 75 per element? i need two Sad

**Curt Palme** · Posted: Fri Feb 18, 2011 1:54 am Post subject:

Clear ones are $50, but yes, the R and G are $75 each, sorry!

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

ouch! will other branded c elements work? i think i saw another brand that has a darker green tint, better?

winduptoy · Posted: Fri Feb 18, 2011 11:42 am Post subject:

Congrats on the new machine! The C elements in a G70 are quite accurate, but to do rec 709 (HD) it would be a little better with a more saturated green. I would only do this if you plan on using a Moome card and running it on HDMI; otherwise the stock elements are fine. I'm still using stock with an HDMI card and I'm quite happy with the picture.
What size screen do you want to drive with it? I'm getting plenty of pop on an 84" screen with the contrast at 58. Unless you have a Lumagen scaler with 11 point grayscale, you'll find pushing the contrast past 60 makes the highlights increasingly yellow. It responds well to bias and gain adjustments @ 60 and under.

REGNAD · Joined: 15 Oct 2006 Posts: 169 Location: RICHMOND VA

i currently have a self built 107" screen of blackout material. its served me well but i want a real screen now with this g70. the blackout material bleeds light to bad. i wouldnt mind going bigger but i would have to spread my Magnepans, and i cant be having that! my dedicated room if roughly 18x30 with a bar in the rear. 107" ok for this pj?

km987654 · Posted: Sun Feb 20, 2011 6:34 am Post subject: