[tsanga]

I just calibrated a friend's Pioneer 5080 using an EODLT and HCFR. The setup is identical to what I used to calibrate my 4280, except that I used his cheapo DVD player (component input) that doesn't process blacker-than-black.


On the 5080, the gamma tracking is a big ski jump looking thing - starts around 2.3, and starts diving all the way through 100% stimulus, down to low 1.x.


On the 4280, using my DVD player (also component input), the gamma is very flat except for 10% stimulus, which is a tad high.


My question is, can the DVD player hose up luminance that badly? I'm wondering if I should schlep my DVD player over to his place and repeat the calibration?


Something noteworthy: while calibrating the 4280, the gamma also started out with a downward tracking slope (but not nearly as drastic). Somewhere during calibration (I have no idea what changed/happened), the contrast setting I used to measure ~34 ftL on a 100% white window suddenly was giving me 26-28 ftL. But a beneficial effect that came with this weird change was the gamma tracking suddenly snapped straight - no sweat, just up the contrast control a bit. This happened some time between iterations of me adjusting R-high and B-high, and it hasn't deviated from it's very flat gamma tracking since.

 

[Michael TLV]

Greetings


All works fine and dandy if you are leaving your DVD player at his place for him to use after.


Calibrate to his source ... not to yours. He watches his stuff.

Don't like his stuff ... then tell him he needs to do better or make due.


regards

 

[tsanga]

But my question was, can a DVD player be so low-end that it really can't even process basic luminance information properly? This one was a Samsung. If I'm going to tell him to get better stuff, I better be able to tell him that results will be better after spending some $ on a new player.

 

[Michael TLV]

Greetings


Gamma is what it is ... since on those sets, you can't do much about it anyway.


Calibrate it correctly and hope the gamma falls into place. If not ... ask yourself if your friend will see a difference in gamma performance when he is watching a movie on his cheap DVD player.


You might... but will he? And would he care?


(obviously ... check the player for its own user controls. DVD players have be known to mess many things up ... even $1000+ players. Not restricted to $50 players.)


regards

 

[tsanga]

Thanks.

Guess the only way to find out for sure is to use my DVD player on his TV and see if the measured response is any different.


Then I can talk to him about whether he cares or not to buy a new one. His current player was free.

 

[tsanga]



Quote:
Originally Posted by Michael TLV /forum/post/14205484


Gamma is what it is ... since on those sets, you can't do much about it anyway.

BTW, there is a 3-position user control for gamma, which is pretty effective at raising or lowering gamma .1-.2 for each click. But this control won't affect the shape of the curve.

 

[Michael TLV]

Greetings


Very limited control. Pick the darkest one and start from there. But you knew that already.

Any new dvd player would be infinitely more expensive than what he has now.

regards

 

[thomasl]



Quote:
Originally Posted by tsanga /forum/post/14205351


My question is, can the DVD player hose up luminance that badly? I'm wondering if I should schlep my DVD player over to his place and repeat the calibration?

tsanga,


It could be the dvd player. It could also be the processing on the input that is being used (is it HDMI or component?). The easiest experiment to do is to leave everything the same and swap in your player and see what results you get. The other thing that you mentioned with regard to your 4280 may be what is causing the luminance compression at the higher end. The overall light output may be too high i.e. contrast is too high. Typically, lowering contrast should help gamma at the high end, shifting the response left to right thus if it drops dramatically, lowering contrast should flatten it out some. So, you could try lowering contrast and see what that does to the gamma curve as you continue to lower it. You then have to find a compromise between light output and gamma response. If you have the HCFR file saved, you could post it which would give folks a better idea of what might be causing the drop in gamma at the high end.


hope this helps,



--tom

 

[blutarsky]

I can witness.... YES!!


I had a crappy DVD/VHS LG combo and was getting crazy, couldn't get anything reasonable...


Switched to the PS3 and VOILA'!!!

 

[tsanga]

blutarksy,


This helps so much! My friend's is a crappy Samsung DVD/VHS combo, and the gamma tracking looks like yours, except multiply the slope of the gamma decrease by 2-3x (hence ski jump curve).


Looks like I'll have to show him why he needs to buy a new player.

 

[blutarsky]

Absolutelty!


P.S. - The crappy DVD player was connected through an Euro-Scart cable.... just to add complexity to the whole pot.


So if you switch to a better player with HDMI, it should be better

 

[delphiplasma]

Yes, the dvd player plays a crucial part in the luminance output. Mine was weird, when used in progressive mode the gamma was much like a ski slope, but when used as interlaced I would be able to acheive a flat gamma response.


I managed to improve the progressive gamma by adjusting, what the manufacturer called, a sharpness control in the DVD player set-up menu.


Much like Hi-Fi, Garbage in; Garbage out!!