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Gamma, and HDMI switching?

post #1 of 26
Thread Starter 
While my Samsung Blu ray looks pretty good on my XG, I have a problem with black crush (don't most of us)
At this time I use Moome's DVI input card on the XG
I have been searching the Gamma threads, but can't seem to find an answer to my question.
What I'd like to do is simply replace my little Radiance HDMI switcher with something that'll no only switch two HDMI inputs, but also add gamma correction...OR, replace the card up on the XG with HDMI and Gamma correction.
As I understand it. Moome is coming out with his external box that has both switching and gamma correction...is this correction adjustable?
Is there another option?
post #2 of 26
Quote:
Originally Posted by KennyG View Post

As I understand it. Moome is coming out with his external box that has both switching and gamma correction...is this correction adjustable?

Yes, it will be adjustable with some preset adjustment points.

Quote:
Originally Posted by KennyG View Post

Is there another option?

With switching? Only a scaler to a DVI/HDMI input. If you don't mind buying a <$40 HDMI switch, the other option is an HDFury plugged into Kim's (crescendo-system RTC2200) transcoder. I'm using this and it is very good (though I've only used this combo on barcos and sony's which have less black crush that NECs and 'Quees, but it should be able to look as good).
post #3 of 26
Dave beat me to it but he's right.... (of course)

If you skip over options like scalers or high-end prepros with built-in gamma adjustment, the two options are:

(1) Moome's EXT-HD external HDMI->RGB converter: Like coming out some time in the next 2-4+ months (release date not really known - I'm guessing here based on past experience).

(2) The HDfury (available now) coupled with the Crescendo systems RTC-2200 reverse transcoder (also availabe now).

The two setups are almost exactly the same price (around $300) and give you pretty much the same features including a digital input (DVI or HDMI) with HDCP, a component input, and adjustable gamma boost on both inputs.

The Moome has a few extras like: a second HDMI input, maybe one component output (unknown), and a remote control. The catch is that Moome's is not out yet of course and there's no firm date set (people have been waiting for quite some time) and the features are still 'tentative'.

But hey, having choices between two or more at all is nice!

Kal
post #4 of 26
Thread Starter 
Quote:
Originally Posted by kal View Post

Dave beat me to it but he's right.... (of course)

If you skip over options like scalers or high-end prepros with built-in gamma adjustment, the two options are:

(1) Moome's EXT-HD external HDMI->RGB converter: Like coming out some time in the next 2-4+ months (release date not really known - I'm guessing here based on past experience).

(2) The HDfury (available now) coupled with the Crescendo systems RTC-2200 reverse transcoder (also availabe now).

The two setups are almost exactly the same price (around $300) and give you pretty much the same features including a digital input (DVI or HDMI) with HDCP, a component input, and adjustable gamma boost on both inputs.

The Moome has a few extras like: a second HDMI input, maybe one component output (unknown), and a remote control. The catch is that Moome's is not out yet of course and there's no firm date set (people have been waiting for quite some time) and the features are still 'tentative'.

But hey, having choices between two or more at all is nice!

Kal


But, I don't need any sort of transcoding, or RGB anymore, as of now I'm digital all the way to the pj. So all I need to do is switch two HDMI inputs, to one HDMI output (well DVI at the pj) and Gamma correct.
post #5 of 26
I was surprised to find that my Blu Ray player (Panasonic DMP-BD10A) has an adjustment for Gamma in addition to Contrast and Brightness. I haven't spent much time with it yet so I don't know how effective it is.

-Mark
post #6 of 26
Quote:
Originally Posted by KennyG View Post

But, I don't need any sort of transcoding, or RGB anymore, as of now I'm digital all the way to the pj. So all I need to do is switch two HDMI inputs, to one HDMI output (well DVI at the pj) and Gamma correct.

Well that's the catch... there's no other easy solutions out there for adding gamma unless you want to build something yourself.

If you want something sooner than later, order the HDfury + RTC-2200 (for gamma) + a Monoprice HDMI switcher (40$) and you'll have most of it by the weekend.

Kal
post #7 of 26
Thread Starter 
Quote:
Originally Posted by kal View Post

Well that's the catch... there's no other easy solutions out there for adding gamma unless you want to build something yourself.

If you want something sooner than later, order the HDfury + RTC-2200 (for gamma) + a Monoprice HDMI switcher (40$) and you'll have most of it by the weekend.

Kal

Kal, thanks for the links
Yeah, it's all a mess right now. If I go with the above option, the Moome XG card I just bought is toast, the HDMI cable running to my pj is toast...I already have a good HDMI switcher, I was just hoping to put all this in one neat box, and stay HDMI all the way...I can see it's not going to happen.
Suppose I'll wait awhile and see what shakes out. Moome's upcoming external box with the DVI output looks like what I want...with all the internal DVI/HDMI to RGB converters sold, this might be a no-brainer.
post #8 of 26
The Gamma correction we are adding is done in the Analogue realm. You can add it before the A to D conversion.

What you need is:

1: Moome HDMI XG card with Gamma (is he making one?)

2. HDMI/DVI adapter right at projector with short ~100mm RGBHV leads.


So how did it go with Doug? Did you get your glowing rasters sorted?
post #9 of 26
Thread Starter 
Quote:
Originally Posted by Mark_A_W View Post

The Gamma correction we are adding is done in the Analogue realm. You can add it before the A to D conversion.

What you need is:

1: Moome HDMI XG card with Gamma (is he making one?)

2. HDMI/DVI adapter right at projector with short ~100mm RGBHV leads.


So how did it go with Doug? Did you get your glowing rasters sorted?


1 If Moome's external box is HDMI input, and DVI output, wouldn't the Gamma correction be done in the digital realm?

2 My DVI adapter is in the pj, so I don't need RGBHV leads...I want my only D to A conversion to be done in the pj.

Doug spent about 4-5 hours working on it...I think it's right, I know it's better than it was before he started. I can get about 4-5 clicks higher into the brightness before it starts to light the rasters.
The problem now is having all HD sources, with a digital feed all the way to the pj, and no way to adjust Gamma.
Doug says the AKB was clamping the bias at a higher level than normal, but the whole pj had been setup for this high biasing, like it was setup for a special use.
post #10 of 26
1. None of the add-on gamma mods (based on TSE's original design) work this way. Of course Gamma can be done digitally, like in a PC, but the mod is analogue.

2. Your DVI adapter is probably no good if you need Gamma.... unless you can adjust it in the source (PC is good here), or Moome's box works as you describe (you might find it has an analogue output with Gamma, and a DVI one without).

Not want you want to hear I guess...sorry. Pasey ditched his XG DVI card and went ISS card for this very reason.
post #11 of 26
Thread Starter 
Man this is rapidly becoming sickening.
So it looks like I've got to pull new RGBHV cables into my conduit, and basically start all over again.
I have e-mailed moome, and am waiting to heard back.
The... madness...is...starting...to...eat...my...brain...
post #12 of 26
Well, there's no need to panic.

You have other options.

- Scaler. VP50 or Lumagen. Gary Murrell went this way.

- Wait for Moome XG HDMI card with gamma.

- Very short RGBHV lines, like I said before. It really wouldn't make much difference. In fact in my testing with a Moome XG DVI card I noticed ringing and the output was too hot anyway. My 10m RGBHV run is just as good, so 100mm of it isn't going to hurt. I think Moome's analogue side of things could be improved.
post #13 of 26
Quote:
Originally Posted by mtmelvin View Post

I was surprised to find that my Blu Ray player (Panasonic DMP-BD10A) has an adjustment for Gamma in addition to Contrast and Brightness. I haven't spent much time with it yet so I don't know how effective it is.

-Mark

This always comes up. This is not the same. The gamma adjustment in a component is adjusting the exponent of the curve, so the curve remains symetrical. The gamma we are talking about targets the under 30 IRE section and reshapes the curve asymmetrically to make up for the lack of phosphor responsiveness at low IREs.
post #14 of 26
Quote:
Originally Posted by Mark_A_W View Post

1: Moome HDMI XG card with Gamma (is he making one?)

Supposedly, yes. But with the IFB-HD (Sony), and VIM-HD (Marquee) not shipping yet, and with the EXT-HD (universal external solution) still to be finished, who knows when the XG card will see the light of day.

I wouldn't hold my breath if you expect to see it in the next 6 months.

Kal
post #15 of 26
Quote:
Originally Posted by Person99 View Post

This always comes up. This is not the same. The gamma adjustment in a component is adjusting the exponent of the curve, so the curve remains symetrical. The gamma we are talking about targets the under 30 IRE section and reshapes the curve asymmetrically to make up for the lack of phosphor responsiveness at low IREs.

Ahhhhh... ok. Thanks for explaining that Dave. I figuered it was too good to be true

-Mark
post #16 of 26
This sounds great! An HDMI switcher with Gamma is exactly what I want. I am glad one will be coming to the market.
post #17 of 26
What one?
post #18 of 26
Thread Starter 
Quote:
Originally Posted by Mark_A_W View Post

Well, there's no need to panic.

You have other options.

- Scaler. VP50 or Lumagen. Gary Murrell went this way.

- Wait for Moome XG HDMI card with gamma.

- Very short RGBHV lines, like I said before. It really wouldn't make much difference. In fact in my testing with a Moome XG DVI card I noticed ringing and the output was too hot anyway. My 10m RGBHV run is just as good, so 100mm of it isn't going to hurt. I think Moome's analogue side of things could be improved.


Yeah, the panic was short lived
I've had a Lumagen HDP vision pro, but found it noisy compared to my MP-5 (which now gathers dust too) So don't want to go back to that...or any scaler.

The Moome HDMI card with gamma is exactly what I need, and am waiting for...I have an e-mail into him about it, I'm just waiting for an answer.
post #19 of 26
Quote:
Originally Posted by KennyG View Post

Yeah, the panic was short lived
I've had a Lumagen HDP vision pro, but found it noisy compared to my MP-5 (which now gathers dust too) So don't want to go back to that...or any scaler.

The Moome HDMI card with gamma is exactly what I need, and am waiting for...I have an e-mail into him about it, I'm just waiting for an answer.


What kind of noise did you experience with the Lumagen HDP vision pro and what equipment did you use it with?
post #20 of 26
Quote:
Originally Posted by Mark_A_W View Post

What one?


I need the external with HDMI in and DVI out.

I have a MJ scaler card on my 9500 that takes DVI in.

I would love to get a good deinterlacer instead of my scaler. My scaler bounces to 540 befor it goes to 1080p. But the new generation deinterlacers are all very expensive are not really in my budget at this point. Gefen has one but I have read mixed reviews.
post #21 of 26
Quote:
Originally Posted by KennyG View Post

I've had a Lumagen HDP vision pro, but found it noisy compared to my MP-5 (which now gathers dust too) So don't want to go back to that...or any scaler.

I'd have to see this to believe it.
post #22 of 26
Quote:
Originally Posted by scottatl View Post

I need the external with HDMI in and DVI out.

I have a MJ scaler card on my 9500 that takes DVI in.

You can still use one with HDMI out. All you need is an HDMI to DVI cable.
post #23 of 26
Thread Starter 
Quote:
Originally Posted by Frank D View Post

What kind of noise did you experience with the Lumagen HDP vision pro and what equipment did you use it with?

The only way you'd see it is to go straight from the lumagen to something like Mike Parker's MP-5...the blacks are deeper, which makes for better shadow detail
AND I was going straight out of a Denon 3910 with SDI mod done by Lumagen (and of coarse my HDP pro had SDi inputs) The MP-5's deeper blacks and better shadow detail are because of decreased noise.
In fact, I may throw the MP-5 back into my system until this DVI vs HDMI color space problem is sorted out.
post #24 of 26
We have made custom gama adjustments for our internal DVI card for Barco projectors but don't have anything made for XG units.

The procedure is easy to modify and if you email me I can tell you how to modify the external boxes to have better gama as they all use the same SIL907 chip.

Greg
post #25 of 26
Quote:
Originally Posted by geisemann View Post

We have made custom gama adjustments for our internal DVI card for Barco projectors but don't have anything made for XG units.

The procedure is easy to modify and if you email me I can tell you how to modify the external boxes to have better gama as they all use the same SIL907 chip.

Greg

Greg, did you add an adjustment just to bump the standard gamma setting? When we talk about his, we are talking about reshaping the gamma curve (targeting the <30 IRE section) to compensate for the phosphor characteristics.
post #26 of 26
There are a couple of ways to do it.

There are a few resistor values you can change on the board.

Or change the EDID.

I posted the schematic a few months back and showed the resistor values to change.

Greg
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