CurtPalme.com Home Theater Forum

garyfritz · Joined: 08 Apr 2006 Posts: 12025 Location: Fort Collins, CO

I finally got a chance to adjust the gamma on my EXT-HD, and I find that even with both the screw and the IR controls maxed, I STILL don't have as much boost as I think I need.

I displayed the "5% step" pattern from the GetGray disk. (See below -- note, this is copied from the GetGray manual, it's NOT a screenshot! The first two bars are "blacker than black." The 3rd bar is "black" or 0%, the 4th bar is 5%, etc.) This pattern shows 5% levels going from 0 to 100%. With the EXT-HD fully maxed out, I can see the 10% step but not the 5% step.

I can see a 5% window just fine, but that's with the rest of the screen black. With other bright things on the screen -- which is when you NEED the boost -- I can't get enough "oomph."

I know the box is working. I can see the boost increasing as I rotate the screw CCW, until it starts to click. I can see the boost changing as I use the IR control, and I've got it maxed. I still can't see some of the shadow detail.

Am I expecting too much? Those of you using the EXT-HD, do you have the GetGray disk or similar 5% pattern? Or does that pattern have too high APL to see the 5% level with an AC projector, even with a gamma boost?

Gary

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

A couple questions:

Did you do a grey scale first before using the gamma.
If you did, did you do another grey scale readings after?
Also when doing the grey scale did you defocus the Blue? It should help out a little with Gamma.
You may need to touch up grey scale after using gamma but not always.

Athanasios

garyfritz · Joined: 08 Apr 2006 Posts: 12025 Location: Fort Collins, CO

Yes, did it before;
no, haven't done it after yet.
Yes, blue is very defocused.

(I did actually tweak the blue gain without doing a full grayscale, because the blue was too bright at 0% while R & G were black. Now I have a pretty dark screen at 0%, whereas before it was plenty bright. But I need to go back and do a proper grayscale.)

jbryngelson · Joined: 02 Jan 2008 Posts: 14

Seems like just the opposite of my problem. I can not adjust the Gamma, and it is far too much on my unit. If I open the box, is there an internal pot to change the GAMMA, or is it only by remote. My remote is not doing anything.

Jeff

garyfritz · Joined: 08 Apr 2006 Posts: 12025 Location: Fort Collins, CO

The remote should make a yellow LED flicker on the face of the box. (The side that the HDMI cables plug into, next to the 7-segment LED display.) When it's maxed all the way up or down, the yellow LED stays on.

Open the box and you'll find a little blue rectangular box, about 3/4" by 1/4" by 1/2", under the ribbon cable behind the LED display. It has a tiny brass screw on one side. Adjust that 25 turns CLOCKWISE to minimize the boost. Then back it off about 12 turns. That should put you in the middle of the screw-adjust range.

I just re-measured my grayscale. The gamma is a bit low (levels too high), gamma = about 2.18, so I guess I should back off on the boost some. But it still looks mighty dark in the shadows. Of course it doesn't help that I'm watching Blade Runner. Smile

jbryngelson · Joined: 02 Jan 2008 Posts: 14

Well, my unit is not responding to the remote. I have changed the batteries to other known working AAA, and I get the same results. I will try brand new batteries today. Any tricks to get the remote to work with the unit? Drop the box from 6" to the counter (JUST KIDDING). Throw the remote at the wall? (STILL KIDDING). It might make me feel better. This is my third Moome product that does not work right. GRRRRRR. I so want it to work!!!!!

Any suggestions?

Also, if I do open the box and adjust the GAMMA Pot, it will affect the Component and HDMI equally - correct? Gamma on the Component is very good.

Jeff in Detroit

ralpharch · Joined: 02 Nov 2007 Posts: 211 Location: Derwood

ralpharch · Joined: 02 Nov 2007 Posts: 211 Location: Derwood

garyfritz · Joined: 08 Apr 2006 Posts: 12025 Location: Fort Collins, CO

ralpharch · Joined: 02 Nov 2007 Posts: 211 Location: Derwood

ralpharch · Joined: 02 Nov 2007 Posts: 211 Location: Derwood

Since I haven't heard anything I emailed moome for feedback. Will post here if I receive a response:

Moome - I have one of the original Ext-HD boxes with VGA and test DVI out. It has two pots on it versus others only have one with the RGBHV BNC version of the card.

Can you please let me know which pot is supposed to be adjusted to change the gamma steps for the box I have? I adjusted the one near the gamma daughterboard (actually just set it to maximum by turning it counterclockwise a number of turns). But another forum member adjusted the pot below the ribbon cable and that appeared to work for him.. Did I mess something up by adjusting that pot? Why are there two pots on my version and one on the BNC version?

see this thread for photo and further description

http://www.curtpalme.com/forum/viewtopic.php?p=137532#137532

Email Moome directly instead of PM'ing him: moome@curtpalme.com.

EDIT
feedback from server

Final-Recipient: RFC822; moome@curtpalme.com
X-Actual-Recipient: RFC822; moome@seed.net.tw
Action: failed
Status: 5.1.1
Remote-MTA: DNS; mx.seed.net.tw
Diagnostic-Code: SMTP; 550 Spam suspect,Your are not Yahoo Server
Last-Attempt-Date: Fri, 29 Aug 2008 11:52:43 -0400

so I tried sending directly to moome instead of through curtpalm.com

ralpharch · Joined: 02 Nov 2007 Posts: 211 Location: Derwood

reply back from Moome:

hi,
you should adjust the VR1 near the DIP40 CPU~

_____

Which doesn't help me much as I don't have a clue what the dip40 cpu is but if I had to guess would be the 40 pin IC near the pot Gary adjusted.

So I assume I probably adjusted the wrong one. (yes)

But maybe not (Wrong) - the manuals Moome provided for the original Ext HD box did show separate VR1s for the VGA and the BNC gamma boost, and all the boards I could see that were in his box showed 2 pots so Gary's seems different in that regard. Even if I did understand still doesn't help to know what the other VR1 does. Oh well, if its not broken don't try to fix it;

http://picasaweb.google.com/Ralpharchi/MoomeBox/photo#5240140230038768882

edit - the below earlier manual for ext-hd did show separate adjustment points for vga and bnc

http://www.curtpalme.com/forum/download.php?id=2961

EDIT- doesn't matter - VR1 it is

VR3 which is clearly labled on board is for component sync - Don;t adjust

**AnalogRocks** · Posted: Sun Aug 31, 2008 8:07 am Post subject: