Service menu Samsung - all values - Page 2

oh, now I see. I bet he's crushing blacks at APL > 20%. You can see from the graph I linked to earlier that the shape of gamma vs. APL spikes above these levels and you can't fix that by upping brightness.

zoyd,

I do not use average picture level (apl) patterns, but just the regular ones. Also, as plasma said, I do not have the 10 pt. on my tv. I use the ganging method to level out gamma.

I have seen black crush before, which gives me a headache while watching. My current settings do not cause headaches. This, however, does not mean that you are wrong. You could be absolutely correct.

Vincentfam

gotcha, when you use standard window patterns you are measuring the gamma response over an average APL of only about 6-7%. If you were to remeasure with APL patterns at say 25-30% you'd measure a considerably higher gamma which would be more representative of real content.

Even if the black clipping pattern shows 17 and up flashing, you could still be crushing blacks; with higher gammas and black tone (if you don't have enough contrast ratio/deep enough black levels), you end up crushing together the steps near-black so that they appear distinct from black/the background (16) but not from each other (17-25 or so). You appear to be doing so given the rather bright black level of your TV (0.039 fL) and the 2.35 gamma combined with aggressive use of the black tone setting. I would also consider using the patterns Zoyd has suggested in place of those what you use now since the new patterns should be more representative of real program material and therefore give you a better picture with more shadow detail.

I'd make the following changes to your calibration (ignoring white balance for the moment):

1) Start with Movie mode

2) Turn off Black Tone

3) Keep average gamma around 2.3 to 2.35

4) Use APL patterns instead of the typical windows

do you use the large or small APL patterns on the AVS disc?

My primary display is a LCD with no dynamic backlight, contrast, or other picture controls active, so APL on my set is irrelevant. I do have an old Panasonic Plasma, but it has no gamma controls so I don't think my pattern choice makes much difference in terms of the end results. Overall, I not that familiar with current plasma TV behavior since all the newer TVs at home are LCDs with dynamic features disabled (if present).

The apl effect,

In using apl large windows, gamma jumped up to 2.53, with peak white @ 41 flL and 0% gray @ 0.035 and minor rgb adjustments to flatten out gamma. A check of brightness level revealed proper setting of 17 per AVS Forum disc. Static contrast ratio jumped to 1191:1.

By the way, tv is in light controlled dark room. Does not appear to have black crush.

Vincentfam

Attachment 247132

Attachment 247133

@Plasma - I used to use the large ones since the small ones average so low, but they are a bit too large so I started using the 25% APL ones here. Even if you have all the dynamic stuff disabled it's worth checking to see if there is any inherent gamma enhancement going on, at least that's the case with samsung and panny plasmas from 2011. Don't know about LCDs

Given the two curves you have posted you look to be ok at low apl where near black gamma is 2-2.1 which is appropriate for your black level but that higher apl gamma would definitely create black crush on my display and I have an mll of 0.007 ftL. You could try to reproduce the first curve using the 25% apl patterns and then compare the two to see what you think.

I agree. A 2.5 gamma is overkill for a display with that kind of black level/contrast ratio, even in a pitch black room with zero reflections. I would not exceed 2.35-2.4 for any modern flat-panel display; for this particular plasma, going past 2.3 to 2.35 overall is probably not ideal. Even a 2.2 or 2.25 gamma could be great on this display.

I use full fields for my LCDs. Results in terms of Y readings are identical to using standard windows.

I can't help but think using standard pic mode is doing some enhancement/processing or something else to the image that is not showing up in your readings (like just-above-black gamma).

I wasn't referring to problems with full field vs. windows. APL patterns are used to to probe display response at constant APL, windows or full fields do not present constant APL so you will not know if the transfer function is APL dependent. I'm not saying it is, but until you test it you won't know.

Here is my transfer function set to the new BT.1886 recommendation for a display with peak white 120 cd/m^2 and black level of 0.03 cd/m^2. My display actually can achieve 0.2 cd/m^2 blacks but only at low APL.

I will give it a try next time I calibrate but I think my LCDs don't change light output based on APL (they don't have the ABL nor the auto dimming backlight or dynamic contrast active).

I know that the usual wisdom is to have 2.2 gamma, but I ran across this posting that promotes 2.5 gamma for displays:

http://www.avsforum.com/avs-vb/showthread.php?t=1008297

Still a dilemma?

Vincentfam

Most don't recommend a gamma higher than 2.4 on any typical display. In your case, the black level/contrast ratio of your display limits how high you can set gamma on your set. You should be okay at 2.3 to 2.35, though 2.2 or 2.25 would be fine as well. Basically anywhere from 2.2 to 2.35 should be good on your TV.

http://www.chromapure.com/colorscience-gamma.asp

http://www.chromapure.com/colorscience-lightness.asp

yeah, that's an old thread. The issue was recently rehashed here, and it's very impractical to try to emulate a "typical" mastering monitor since there is no such thing and most commercial displays can't achieve the black levels required anyway. I believe the new recommendation is a good compromise to the situation and consistent with Plasma's note above.

btw - BT.1886 recommends a flat 2.4 if mll < 0.01 cd/m^2 but does not specify any conditions on viewing environment.

Thanks for your recommendations colleagues.

I have reduced the gamma to 2.4, using the large apl patterns. Real gamma may be 2.35. Noticed more detail in dark areas and picture is brighter. My environment is the dark man cave. I will post new settings on thread in this forum and provide feedback, if received.

Picture looks great.

Vincentfam

It is ironic that this latter discussion has absolutely nothing to do with "Service Menu Samsung."