[buzzard767]

Originally Posted by Gordon @ Convergent AV

This is an old quote and is not really any longer pertinent. It is a description of red push but it is quite incorrect to suggest that all current tv's have red push built in to their colour decoders. Also
"This explains why skin tones are wrong even on perfectly calibrated set"
a perfectly calibrated set will not have any colour decoder errors.

I don't know about the Euro models but many US Panasonics and Samsungs are the same as always. Some come incredibly blue from the factory and in the end Color must be reduced several points to yield acceptable flesh tones.

The following report is from a Samsung UN46D8000 LED I did last month. Don't laugh at the 74fL peak white - the room requires it.

Britto UN46D8000Reduced.pdf

Buzz
THX Certified Video Calibrator

[Gordon @ Convergent AV]

Yes there are some...not ALL though.

74ftL...NICE...I had a client who wanted his Samsung LCD calibrated at max possible light output. It was BLINDING...He was happy in end though, even if it wasn't what I'd have called accurate.

[rinkydinkydoo]

@Buzzard767.
Cheers for posting these results, it helps people like me who are starting out! Was the pre report done off a Dynamic/Vivid setting or how the user had set it up?
Andy

[buzzard767]

Originally Posted by rinkydinkydoo

@Buzzard767.
Cheers for posting these results, it helps people like me who are starting out! Was the pre report done off a Dynamic/Vivid setting or how the user had set it up?
Andy

I measure the Befores exactly as I find the display and in this case it was in Normal. I remember because he commented that, as a four day a week golfer, he couldn't stand the neon green grass in the Dynamic mode.

For what it's worth, the Samsung 8000s calibrate very well but the red push did require a Color reduction to about 45. Midpoint is 50. It's a shame because reducing Color (chroma gain) for the most part decreases luminance in all three primaries so even if skin tones look better the rest of the colors lose some of their brightness pop. None the less, the final picture was excellent.

I've mentioned the following before but I think it should be repeated as I feel it's worth a try. If you calibrate, the Samsungs have a Flesh Tone control which does create a minor visual change so you might want to take a glance at using it. Strangely enough, when I measured my own PN51D8000 there were negligible measured differences between the Flesh Tone extremes of +15 and -15. ??????

Buzz
THX Certified Video Calibrator

[rinkydinkydoo]

Originally Posted by buzzard767

I measure the Befores exactly as I find the display and in this case it was in Normal. I remember because he commented that, as a four day a week golfer, he couldn't stand the neon green grass in the Dynamic mode.

For what it's worth, the Samsung 8000s calibrate very well but the red push did require a Color reduction to about 45. Midpoint is 50. It's a shame because reducing Color (chroma gain) for the most part decreases luminance in all three primaries so even if skin tones look better the rest of the colors lose some of their brightness pop. None the less, the final picture was excellent.

I've mentioned the following before but I think it should be repeated as I feel it's worth a try. If you calibrate, the Samsungs have a Flesh Tone control which does create a minor visual change so you might want to take a glance at using it. Strangely enough, when I measured my own PN51D8000 there were negligible measured differences between the Flesh Tone extremes of +15 and -15. ??????

Buzz
THX Certified Video Calibrator

Hi Buzz,
Thanks for the quick response.
Wow, what a difference. Must be nice to do, as the improvements are so drastic.
I have started out with my Panasonic and early results are good. I noted a lot of green and can now see how blue the whites were prior to calibration.
Got a way to go yet but have been very impressed with Chromapure.
I'm also having a go at Farenheits hood setup as calibrating at night is not ideal.
Andy

[RICKYJ]

Version 2.2.12 released. More info in our AVF blog here

[tele1962]

Originally Posted by RICKYJ

Version 2.2.12 released. More info in our AVF blog here

In downloading this is it automatically saved/updated to my current version of Chromapure?

[RICKYJ]

Originally Posted by tele1962

In downloading this is it automatically saved/updated to my current version of Chromapure?

Barry, you need to download the Zip, and unzip to a convenient location. Uninstall the version you currently have installed (using add/remove programs), and then run the unzipped file from earlier. Once you installed, run CP and check the bottom right of the window, where it tells you what version you are running.

[skullface]

wondering if someone could take a quick look at this picture, the heavy redshift in the 20-40% area caused me trouble to dial out with RGB gains/offset. Mainly I think because the curve goes up and then back down.. Should this be dialled out with Red Gamma curve adjustments at the lower IRE instead?

Also looks like I could lower the Green offset a little and up the gain OR should it be on the Blue increase offset decrease gain to level out the blue/green deviance?

This is my first attempt with Chromapure / Display 3 / AVS HD709 since giving up on an old Sypder color pro a while back, So I'll understand if I've made a silly error somewhere and it gets pointed out.

Thanks in advance for any help.

[rinkydinkydoo]

Hi,
2.2.13 is out peeps! here

[MeanDorris]

Originally Posted by skullface

wondering if someone could take a quick look at this picture, the heavy redshift in the 20-40% area caused me trouble to dial out with RGB gains/offset. Mainly I think because the curve goes up and then back down.. Should this be dialled out with Red Gamma curve adjustments at the lower IRE instead?

Also looks like I could lower the Green offset a little and up the gain OR should it be on the Blue increase offset decrease gain to level out the blue/green deviance?

This is my first attempt with Chromapure / Display 3 / AVS HD709 since giving up on an old Sypder color pro a while back, So I'll understand if I've made a silly error somewhere and it gets pointed out.

Thanks in advance for any help.

Hi,

If you put up a 30% grey pattern what does it look like visually, is there a noticeable red shift compared to say 50% or 60%?

The first thing is, my display 3 under reads red compared to my eye1 Pro, so if yours is doing the same (seems quite common with Xrite) then the shift may be more than being measured.

I have generally found adjusting the offsets on the JVC's (I have an X7) causes quite a mess (sudden very noticeable colour shifts at certain IRE's) and you may be better off leaving the offsets alone and just use the separate RGB gamma adjustments to dial it in (as you have suggested) but do this with care. With my signal generator I am able to go up from 0IRE in 1IRE increments and still find at certain levels colour shifts can be introduced.

[Wull]

Originally Posted by MeanDorris

Hi,

If you put up a 30% grey pattern what does it look like visually, is there a noticeable red shift compared to say 50% or 60%?

The first thing is, my display 3 under reads red compared to my eye1 Pro, so if yours is doing the same (seems quite common with Xrite) then the shift may be more than being measured.

I have generally found adjusting the offsets on the JVC's (I have an X7) causes quite a mess (sudden very noticeable colour shifts at certain IRE's) and you may be better off leaving the offsets alone and just use the separate RGB gamma adjustments to dial it in (as you have suggested) but do this with care. With my signal generator I am able to go up from 0IRE in 1IRE increments and still find at certain levels colour shifts can be introduced.

Just got a D3 which I hope to use tomorrow 'if I get chance'. Now I normally adjust my TV's and PJ 'JVC 350' GRB offsets at 30% & 80% to correct the white balance before commencing with Chromapure.

Are you suggesting I shouldn't?

[Canti1982]

I am currently trying to calibrate a cheap Philips LCD which has very limited controls, just brightness contrast and tint RGB.

Ricky calibrated my meter a while back and gave me some offset files for Samsung LCD and Sony LCD. I have done it without the offset file and it seems to come out with a slight yellow tint. Would using one of these offsets be suitable to use, I tried breifly with mixed results so I am wondering if my meter (i1 LT) has maybe drifted.

If anyone has any advice it would be greatly appreciated, cheers.

[$weetFA]

Cheers Ricky my new toy has arrived.

[Wull]

Originally Posted by Wull

Just got a D3 which I hope to use tomorrow 'if I get chance'. Now I normally adjust my TV's and PJ 'JVC 350' GRB offsets at 30% & 80% to correct the white balance before commencing with Chromapure.

Are you suggesting I shouldn't?

I will answer this myself.

I got a sweet results after adjusting the 30% & 80% Gain and offsets before commencing Chromapure auto Cal, then manually tweaking at the end. Best picture I have seen on my 350 so far.

[KelvinS1965]

I saw a thread on AVS regarding using Chromapure Pro with a Lumagen VP for auto calibration of 125 points. It's a combination of a (free) firmware update for the Radiance range of processors (including the Mini3D ) plus an update to Chromapure (small fee I believe for Pro users).

Apparently will take about an hour to do the full auto calibration so that the colour gamut is adjusted at different stimulations rather than just for the 6 colours. This will help displays with non linear colour gamut response...ie it's a big deal.

See the Chromapure news page for details of version 2.3:

ChromaPure Video Calibration Software

Tom Huffman also mentioned the possibility of being able to set gamma to the newer BT 1886 standard(?) in a future version.

[Avi]

Originally Posted by KelvinS1965

Tom Huffman also mentioned the possibility of being able to set gamma to the newer BT 1886 standard(?) in a future version.

Given others are releasing/have released software with a BT1886 target I'd be surprised if Chromapure didn't pretty soon.

I guess it's more of an issue for those that use auto cal or need charts showing target ref/actual etc. I don't know about Chromapure but with other software it's possible to manually calibrate to BT1886 but you just need to calculate the necessary luminance targets yourself using a spreadsheet etc.

Avi

[KelvinS1965]

I'm sure you're right about using spreadsheets, etc, but I've long since passed that stage...I just want to be able to run a calibration and use the display.

It seems (from the little I've read) that BT 1886 gives a gamma response not dissimilar to what I do by hand: Lower gamma below 30% moving to higher gamma above 30%. Currently I'd have to do a 2.2 (or ideally 2.3 calibration) then tweak the 21 points manually. I haven't read enough about BT1886 but if it's possible just to tick a box in Chromapure before a calibration then I'd be interested to compare it my modified '2.3 mid range dropping to 2.1 low end' set up.

[Avi]

Originally Posted by KelvinS1965

I'm sure you're right about using spreadsheets, etc, but I've long since passed that stage...I just want to be able to run a calibration and use the display.

It seems (from the little I've read) that BT 1886 gives a gamma response not dissimilar to what I do by hand: Lower gamma below 30% moving to higher gamma above 30%. Currently I'd have to do a 2.2 (or ideally 2.3 calibration) then tweak the 21 points manually. I haven't read enough about BT1886 but if it's possible just to tick a box in Chromapure before a calibration then I'd be interested to compare it my modified '2.3 mid range dropping to 2.1 low end' set up.

I've calibrated to BT 1886 manually. It's not particularly difficult relative to any manual calibration.

BT 1886 calculates EOTF based on the actual measured MML and peak white of a given display/environment. Depending on those numbers the results may vary from a flat 2.4 to something that has a different response at each stim level.

Ideally the result is flat 2.4 response at each level if the display performance supports it. If not the goal is "perceptual uniformity" with a display that does.

Avi

[KelvinS1965]

I'd imagine that the hardest part will be measuring the MML of a modern display. Even with my old 40" Sony LCD my sensor was struggling to give repeatable results.

I found that 2.4 gamma was too high for my old HD350 projector and both my older LCD TVs (all fed and calibrated via my Mini3D). Instead I ended up with 2.2 for the TVs, again lowering towards 2.1 then 2.0 at 5%. For the HD350 I had 2.3 and lowered below 30% ending on 2.1/2.0 at 5% (can't remember which now). I think that these displays didn't have the on/off contrast to support any higher gamma, but it seems that BT 1886 takes this into account, so more a formalised version of what I've been doing.

One thing is clear to me though: When I first got Chromapure I found it so much easier to try different calibration settings that I could save and compare with paused scenes. From this I learnt that I liked the depth of 2.3 gamma on the HD350, but the lower gamma below 30% to help with shadow detail that the lower contrast of the HD350 (compared with the newer models) would otherwise have lost. Prior to that it was so much hard work just getting a good calibration with a straight 2.2 gamma that I didn't have chance to try alternatives.

[Avi]

Originally Posted by KelvinS1965

I'd imagine that the hardest part will be measuring the MML of a modern display. Even with my old 40" Sony LCD my sensor was struggling to give repeatable results.

I guess it depends on the sensor and display.

Certainly with something like the i1 Pro spectro it struggles with anything approaching a low level with claimed sensitivity down to 0.2 cd/m2. The i1 Display Pro is probably the best low cost meter in this regard with claimed 0.003 cd/m2 and is significantly better than the older models it essentially replaces. The Kline K10 claimed 0.00006 cd/m2 but costs a bit more.

Avi

[saltanar]

I have display 3 and eye one pro.
What is the better way to use these?
Use the second?
Calibrate the first with Eye one pro?.
Please helm i'm new on this.
Thanks.

[KelvinS1965]

I believe the 3 is more sensitive to low light levels and also doesn't require resetting the black level every ten minutes (can't remember what they call that now) like the i1Pro. However the i1Pro is usually more accurate so best to create an offset and use the i1Pro as the reference and make the D3 the 'field' meter. You set up the i1Pro and Chromapure measures RGBYCMW and then you measure the same display without changing any settings using the D3 to measure RGBYCMW* in the appropriate area of Chromapure.

You will need a licence for both meters to be able to do this.


* Red, green, blue, yellow, cyan, magenta & white.

[samhain]

interesting development with the radiance mini 3d which I have. In order to benefit from this extended calibration do you need; Chromapure Standard+Autocal add on+ Advanced Auto-Calibrate Add-On. So the 3 elements?

[RICKYJ]

Originally Posted by samhain

interesting development with the radiance mini 3d which I have. In order to benefit from this extended calibration do you need; Chromapure Standard+Autocal add on+ Advanced Auto-Calibrate Add-On. So the 3 elements?

Yes, or just buy ChromaPure standard and Advanced Auto Cal as a new user

[samhain]

2 instead of 3 i can see the efficiency there. comes put at the same price though either way

[sniffer66]

Any recommendation on what to do with a PJ with a brand new bulb now ? In the old days of pro only calibrations it was recommended to wait 100 hours to allow the bulb to settle, before gettign someone in. But just but a new bulb in my HD1 and its a light cannon again. Just run a quick autocal to get the numbers about right and re-do it in a few weeks time I guess ?

[KelvinS1965]

Hell I calibrated my HD350 about 4 times in the first 100 hours. With the autocal, no harm in doing it now and then checking in another 50 hours, with a 'final' cal at 100 hours. If nothing else, it'll show how things change and/or level off.

[sniffer66]

Cheers kelvin, that was my thought as well

The difference is pretty incredilble tbh, I should have done it ages ago. Its like having a brand new PJ

[KelvinS1965]

I found the same: Compare a fully calibrated image via the Lumagen with the gamma just spot on, with the non calibrated version and it really could be a different projector. Looking forward to trying the autocal and 125 point CMS with my own displays (maybe even an X30 if I get any interest in my wanted advert).