CurtPalme.com Home Theater Forum

[dropzone7]

I thought I would start a new thread so as not to further clutter the main one dealing with Kal's guide. I'm posting some before and after graphs mainly for my own reference and to help document what I have done so far. I have to say that after my initial measurements I was confused about how all of that translates to the picture I see on screen. I thought it looked pretty good really. Well, last night was about a 5 hour session of squinting in the dark to read Kal's guide and go through all of the RGB HighEnd / LowEnd adjustments (did not touch Green as suggested). Wow! What a difference! Just with what I have done so far it's so much smoother and I had no idea how much my convergence was affected by bad greyscale and brightness settings. After this last session my convergence actually looks better than ever with crisper white lines with little to no color bleeding over. I still have a lot of work to do and I have yet to add my RTC2200 back into the chain for gamma boost so although my gamma improved after greyscale calibration, I expect it will get better when I reintroduce the RTC2200. After reviewing the data the thing that sticks out like a sore thumb now is my RGB levels below 30IRE. They are all over the place! What should I do to try and flatten those out? Just looking for comments and suggestions.


Measures - Before


Measures - After


RGB - Before


RGB - After


Gamma - Before


Gamma - After

[garyfritz]

[dropzone7]

Thanks for the comments Gary. Maybe it was just late and I was getting tired but my convergence did seem improved after I finished the greyscale. I'm not sure it would be a contrast issue because I normally run that at about 55 but right now it's at 75 which is factory default and what Kal recommends for doing the greyscale. I had also set brightness at default of 60 which is higher than my normal 44 or so when I have the gamma applied. When I finished adjustments which included following the guides procedure for setting brightness and contrast, I was at 47 for brightness and contrast was left at 75 if I remember correctly. I really can't put a finger on what may have caused this perhaps perceived improvement in convergence but I should say that I spent about an hour of last night's session tweaking convergence and redoing optical and electronic focus. Anyway, I apparently did something right and on top of that I THINK I took a step in the right direction with my greyscale. Back at it tonight I hope.

Oh yeah, you might be right about the sensor in the lower end measurements because the numbers kept jumping around all over the place, updating like every second or less instead of every three seconds or so in the above 30IRE readings. Still, much better than the Spyder II which I tried a few months ago.

[dropzone7]

Well, I have done this procedure about six times now and I'm still not satisfied. I'm having a big problem with gamma and luminance. My luminance measures are well above the target value even with brightness pretty low (app. 41) and gamma all the way down. My gamma hovers around 1.87 to 2.01 which if I read the guide correctly means that my gamma is too high as the lower numbers mean too MUCH gamma? I have turned gamma up and down as well as adjusting brightness several times using the video black / pluge pattern and still my results are near the same. I even tried adjusting brightness using the less subjective method of taking the Y reading and multiplying by 0.0065 and using that result as my target Y value for brightness measured with a 10IRE pattern. Although I preferred that method it did not seem to help with my high luminance and low gamma numbers, or is it high gamma numbers? Very confusing. The one thing I have not changed in all of these readings and adjustments is my contrast value. I'm set at contrast of 75 and am within or very close to the target foot lambert value for a projector. Should I try turning contrast down? Will it have an effect on my luminance and or gamma numbers the way that brightness does? BTW, this Eye-One meter is not doing so well in the lower IRE readings. The measurements are all over the place and won't stabilize. I can't get a Delta-E of less than about 80 for 10IRE and 0IRE is above 150 Delta-E. Help!!

[kal]

[kal]

[dropzone7]

[dropzone7]

I just can't seem to get this right. My measurements of luminance from day one have been too high according to the target range. I tried lowering contrast last night (from 75 to 65) because it's the only thing that has remained constant since I started this. I also lowered brightness after once again trying the Y measured value at 10IRE. It looked better the last time I tried that but this time it was too bright. I lowered it more judging by eye using the 0IRE pattern with the black bars. Well, as you can see from the graph below my red took a major dump at 50IRE for some reason. You can also see from the next graph that my luminance is still way high from the target. This is with gamma boost all the way off, brightness at 47 and contrast at 65. The gamma numbers did improve some and while it takes a steep drop my average is now 2.00. I don't understand what's going on and what I should do next really.

[Nashou66]

Drop are you defocusing the blue at all I didnt throughroly read through your entire post.
It can help gamma bit but some times a higher gamma is ok, it depends on what your looking at on the screen, if it looks better than before be happy !

Athanasios

[dropzone7]

Athanasios, I have the blue defocus turned "ON" in the options menu and I have also done some electronic defocus (set at +15) and it looks very defocused to me. I can already see the blue fringing around white text. I tried some different things last night including turning the gamma boost all the way up and recalibrating and also trying a few different brightness settings with the gamma all the way up. Some items improved while others got worse. It's difficult to find that fine balance I suppose.

Scan #1











Scan #2

[dropzone7]

A question for anyone that cares to respond. Although Kal's guide refers to calibrating RGB levels at the 30IRE and 80IRE patterns, would it be beneficial at all or advisable to try calibrating at other levels such as 20IRE and 50IRE? I continue to get a severe dip in red at 50IRE. However, I have finally reached a near target level with my luminance and average gamma. Attached is my latest attempt. Any suggestions?