AVS Forum banner
1 - 20 of 25 Posts

·
Registered
Joined
·
73 Posts
Discussion Starter · #1 ·
Hi all.

I'm pretty new to calibrating TVs. Never thought of doing it until these forums.



Anyway I ended up purchasing an eyeone and downloaded hcfr to play with my tv.


when working on the greyscale i can't seem to flatten out the gamma curve without lowering the contrast significantly.


i've seen people post chc files with gamma going 2.2 straight across and contrast near 100 on this set.


if i have contrast at 100 my gamma slopes from 2.5 at low ires to 1.9 at high ires.


i've only been doing this 2 days so i'm assuming i'm missing something? is there a trick that i don't know about?

 

·
Registered
Joined
·
6,723 Posts
Greetings


When doing grayscale ... work on the gain controls first ... then the offsets. Not the other way around.


I worked on a 850 last night. Just fine. Dark end started to go green so we had to compromise the 30 range.


regards
 

·
Registered
Joined
·
7,056 Posts

Quote:
Originally Posted by ooa4oo /forum/post/15426849


Hi all.

I'm pretty new to calibrating TVs. Never thought of doing it until these forums.



Anyway I ended up purchasing an eyeone and downloaded hcfr to play with my tv.


when working on the greyscale i can't seem to flatten out the gamma curve without lowering the contrast significantly.


i've seen people post chc files with gamma going 2.2 straight across and contrast near 100 on this set.


if i have contrast at 100 my gamma slopes from 2.5 at low ires to 1.9 at high ires.


i've only been doing this 2 days so i'm assuming i'm missing something? is there a trick that i don't know about?


I have a very similiar problem with my toshiba set, I don't have any good answers, but lowering the gains seems to help for my set, then you can turn contrast back up a bit. While they both seem to interact with the gamma curve they do it in slightly different ways. My set will start at 2.2 and noise dive to lie 1.6 at high IREs
 

·
Registered
Joined
·
73 Posts
Discussion Starter · #4 ·

Quote:
Originally Posted by Michael TLV /forum/post/15426974


Greetings


When doing grayscale ... work on the gain controls first ... then the offsets. Not the other way around.


I worked on a 850 last night. Just fine. Dark end started to go green so we had to compromise the 30 range.


regards

i followed the dummies guide by doing gains at 80 first then offsets at 30.

then i'd tweak the rest from there.

is that correct?


things go ok its just i don't know how people get their gamma to be perfectly horizontal while keeping the contrast at 100. i feel like its impossible and i have to reduce contrast unless there is something i'm totally not aware of.
 

·
Registered
Joined
·
132 Posts
If you are adjusting from the Movie mode, user settings, assure that the Dynamic contrast is off. It may help readers if you state the settings you are starting from. If you are in the UM or SM, Expert or not Expert mode, any thing relevant too.
 

·
Registered
Joined
·
73 Posts
Discussion Starter · #6 ·
I'm working through the user menu in movie mode warm2.

can some people who have calibrated 850s tell me if their gamma is 2.2 all across?

and if it is can you tell me where your contrast is set at?

i'd just like to get an idea of what i should be around...
 

·
Registered
Joined
·
6,723 Posts
Greetings


Set your gamma to -3 ... the lowest it can go.


regards
 

·
Registered
Joined
·
73 Posts
Discussion Starter · #8 ·

Quote:
Originally Posted by Michael TLV /forum/post/15434832


Greetings


Set your gamma to -3 ... the lowest it can go.


regards

samsung's gamma settings would shift the curve up or down, but the shape stayed the same.


i finally realized the issue was my blu-ray player.

the panny bd35 really messes with the gamma.

there are 5 different picture modes in the display settings, and each mode would alter the shape of the gamma curve.

along with that, in the user picture mode there is a gamma adjustment and each of those five settings also slightly alter the shape of the gamma curve.

there is a cinema picture mode, but it adjusts brightness(and maybe contrast?) on the fly so its not so great.

the flattest gamma curve would be with user setting and gamma at 5(default 0), but that drops the gamma to 2.1.

luckily the samsung has gamma controls for me to bring the curve back up to 2.3.


so those with a bd35, be aware that your picture display setting can affect your gamma!


interesting that the bluray player has more gamma adjustments than the tv.



thanks for everyone's effort to help me out.
 

·
Registered
Joined
·
442 Posts
Did you have to up the gama on the 850 more than with other sources after adjusting the BD35 to +5?


The reason for asking is that all my sources passes my onkyo 805 receiver and reaches the tv on hdmi1. Since all the other sources is more or less the same I cant compensate just for one source on the tv settings.
 

·
Registered
Joined
·
442 Posts

Quote:
Originally Posted by Michael TLV /forum/post/15426974


Greetings


When doing grayscale ... work on the gain controls first ... then the offsets. Not the other way around.


I worked on a 850 last night. Just fine. Dark end started to go green so we had to compromise the 30 range.


regards

Hope I can ask you a question. I have a 850. Im using movie mode warm2.


I have noticed something. When I do a normal calibration using HD 709 I need to set the gamma on the tv to +3 to get 2.2 gamma.


Dynamic contrast is turned off. But there is still something making the picture darker automatically (sneaky blackness). If I open a small "tv menu" the auto darkness will not happen. So if I open that small "tv menu" (away from the center where the calibration is done) then do the gamma calibration I only need to set the gamma on the tv to +1 to get it to 2.2.


Now my question would be. Should I calibrate the screen normally? Or should I prevent the auto darkness from happening by keeping a small menu (f example brightness setting) open while doing the calibration? What would be the correct end result?


Dosent a gamma +3 setting sound extreme? I can see some other reviewers on the net get a result off +3 on the 750 and 850.
 

·
Registered
Joined
·
6,723 Posts
Greetings


We turn off all auto this or that crap before calibration. No dynamic this or that either.


All off ...


regards
 

·
Registered
Joined
·
442 Posts

Quote:
Originally Posted by Michael TLV /forum/post/15719668


Greetings


We turn off all auto this or that crap before calibration. No dynamic this or that either.


All off ...


regards

I have done that. See settings below. Still it happens. Its almost like if its a dark picture the tv gets the idea, hey lets make it a tad darker. Its impossible to see without taking readings.


One can easily check it. Do a brightness reading while keeping the tvs brightness menu on (make sure it dosent pop back to the main menu and destroy your reading). You will get a higher number than when you close the menus. Any "tv menu" will do, just make sure its far away from the center where the calibration is done.


Also using the computer Ive seen this anomoly once or twice. Opened a small dark picture. Now pay attension the picture suddenly got darker....


Firmware 1005


Movie Mode:


Backlight 4

Contrast 100

Brightness 45

Sharpness 0

Color 53

Tint G/R: G50/R50

Black adjust off

Dynamic contrast off

Gama +1

Color space Auto


White Balance:

R Offset 25

G Offset 28

B Offset 23

R Gain 22

G Gain 24

B Gain 28


Flresh Tone 0

Edge Enhancement off

xycc off

Color Tone Warm2

Size Just Scan

Digital NR off

HDMI black Level Low

100Hz Motion Pluss off

Blue only Mode off

Enery Saving: off
 

·
Registered
Joined
·
6,723 Posts
Greetings


Sometimes the backlight control does weird things ... pump it to max ... 10 or whatever ... and see ...


Welcome to LED localized dimming?


Regards
 

·
Registered
Joined
·
669 Posts

Quote:
Originally Posted by magnusr /forum/post/15719711


I have done that. See settings below. Still it happens. Its almost like if its a dark picture the tv gets the idea, hey lets make it a tad darker. Its impossible to see without taking readings.

Yes, what Michael mentioned sounds like what you're experiencing - LED local dimming processing. The display will try and selectively turn off the light source for parts of the screen if it senses that it should be "dark." This will most likely lead to different readings if you have a menu up on the screen vs. nothing. It's also possible that there is more internal processing on these sets that is trying to squeeze the darkest possible black out of them when they sense the screen would be dark. Since there is probably no way to turn this off (have you looked through the thread for your tv in the LCD forum - there may be more info there about this processing), I would try and calibrate without the menu up on the screen.


hope this helps,



--tom
 

·
Registered
Joined
·
440 Posts

Quote:
Originally Posted by ooa4oo /forum/post/15426849


Hi all.

I'm pretty new to calibrating TVs. Never thought of doing it until these forums.



Anyway I ended up purchasing an eyeone and downloaded hcfr to play with my tv.


when working on the greyscale i can't seem to flatten out the gamma curve without lowering the contrast significantly.


i've seen people post chc files with gamma going 2.2 straight across and contrast near 100 on this set.


if i have contrast at 100 my gamma slopes from 2.5 at low ires to 1.9 at high ires.


i've only been doing this 2 days so i'm assuming i'm missing something? is there a trick that i don't know about?


I have the BD35 as well and picture mode should be left on NORMAL at all times. That is sending a clean untouched signal to the set.


I do get the flattest Gamma response at about 90 Picture on this set (PZ85 Plasma though). But then my gamma is 2.1 and my peak light output ends up going from 35 ftL to 36ftL (60 Pic versus 90 Pic). So I had to give up a little gamma linearity/flatness to acheive 2.2 gamma average and 35 ftL (measured from a 100% stimulus White Window).


I would greatly love it if you could post your BEFORE chc file from your out of the box Cinema (or whatever Samsung calls it) settings from that TV with the BD35 in NORMAL (Default) mode. Which disk you using for patterns?


C.
 

·
Registered
Joined
·
442 Posts
Allright I will stick with gamma +1.


See the data below. Target is what its supposed to be. when its a w after the gamma setting it means the gamma menu was open during calibration. The 30% 40% etc means the pattern used.


Pattern G---, 20,0%, 30,0 %, 40,0 %, 50,0 %, 60,0 %, 70,0 %, 80,0 %, 90,0 %

Gamma +1--, 0,0209, 0,0547, 0,1295, 0,2209, 0,3275, 0,4560, 0,6 080, 0,7850

Gamma +1 w, 0,0268, 0,0647, 0,1373, 0,2228, 0,3270, 0,4554, 0, 6083,

Gamma +2--, 0,0237, 0,0611, 0,1406, 0,2382, 0,3480, 0,4742, 0,6 273,

Gamma +2 w, 0,0307, 0,0710, 0,1497, 0,2394, 0,3470, 0,4739, 0, 6276,

Gamma +3--, 0,0271, 0,0619, 0,1530, 0,2557, 0,3678, 0,4927, 0,6 447,

Gamma +3 w, 0,0348, 0,0798, 0,1646, 0,2559, 0,3681, 0,4925, 0, 6452,

Target------, 0,0290, 0,0707, 0,1332, 0,2176, 0,3250, 0,4563, 0,6 121, 0,7931
 

·
Registered
Joined
·
6,622 Posts

Quote:
Originally Posted by cvearl /forum/post/15732467


I have the BD35 as well and picture mode should be left on NORMAL at all times. That is sending a clean untouched signal to the set.

C.

I'm with C on this one.
You want as little processing from the source as possible.
 
1 - 20 of 25 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top