15 replies to this topic

[renfield sonia]

Anyone knows any tool to calibrate LED monitors?

[Phil Rhodes]

When you say "LED monitor", do you mean a TFT monitor with an LED backlight, or an actual OLED display?

Almost certainly the situation is the former, in which case I'd treat it as a TFT and see how things turn out.

I'm not really sure the situation ought to be different in either case, anyway - the purpose of calibration is, in part, to even out these differences in technology.

P

[renfield sonia]

It's a LED backlight monitor, the director has bought this tv as a reference for the color correction process, he will correct the image using apple color, apple cinema displays and this monitor as a reference. When I saw the two screens at producion meeting I noticed the huge difference between the two screens... but didn't have time to check the two basic settings (temperature and standards). The point is to match the two displays while setting a proper and neutral calibration so they can perform a proper color correction, for that I've been looking for average tools and found out a spider series, have you heard about them?

[renfield sonia]

Wikipedia says that those monitors inherit the exact same features that the panel in which it's been built but enhancing the elements related with lighting, so I guess you were right in the question about treating them as a regular LCD screen (so the answer would be to use the same calibration tool for both cinema display and LED backlight monitor)

[renfield sonia]

We finally decided to buy a spider calibrator, the reasons where the following: I called samsung to ask about the possibilities to calibrate their tv LCD led monitors and didn't have a clue about what I was talking about, they just answer that this monitors could only be calibrated manually and trusting the eye. So we decided to start by calibrating our cinema display and then try to match the other screen by eye. I don't know yet the answer but I think that it's possible to calibrate this TV LCD even through the computer, as it's the graphic chart what's controlling the display being output to the TV... so the calibration tool would have the ability to create the corresponding profiles...

[Phil Rhodes]

Fair enough. Unless you're going to go for Truelight or somesuch incredibly expensive item, that's about all you can do I think.

Bear in mind that most TFT monitors can't really be calibrated to anything in particular, anyway. You can get the colour right, or sort of right, and you can get the gamma sort of reasonably roughly OK, within the limits of the black level being too high. TFT does not do black. The only things that will really calibrate are 3-chip DLP projectors and CRTs, and anyone who tells you otherwise is just trying to sell you an expensive lookup table...

P

[renfield sonia]

Thanks for the tips Phil, I have another question, now about the ambient light on the edition room. I asked yesturday to the seller if the ambient light was taken in consideration while profiling the monitor, he told me that it wasn't. So, let's say the LCD monitor white point is natively 6500K (which is kind of a standard in us or europe), my quesiont would be if this has to be our starting point for ambient illumination, should it match this white point so to avoid chroma dominants to appear by contrast? (sort of metamerism?). The director told me that, even no direct light is hiting the screens, they use to work under different lighting conditions, let's say daylight shadow during the day and maybe tungsten during the night... which could be a problem during serious color correction isn't it?

[Frank Glencairn]

The Spyder has a ambient light sensor, so you should be fine.

Frank

[renfield sonia]

Ok, I could calibrate the cinema display but couldn't achieve to match the two monitors (thomson TV LCD LED)...
In addition to this problem I find the next issue: whenever I open a flat grey image, it's shown differently in photoshop, apple color and final cut... with slights dominants for each one... now it's time to dig into the way those programs deal with color profiles and so... so now, what would be the starting point in a regular color correction? I've find that the presets I created in final cut so to match the LUTs created on set for the correct display on monitors are imported weirdly on apple color, that seems to keep the color correction but giving a quite different color dominance than the display on final cut... of course, the director is now used to fcp look so he wants to keep that during grading... now I really don't know where to start with...

[Hal Smith]

The only things that will really calibrate are 3-chip DLP projectors and CRTs, and anyone who tells you otherwise is just trying to sell you an expensive lookup table...

HP Dreamcolors calibrate nicely...but also cost more than $2K US. Among other virtues, it's a true 10 bit design.

Dreamcolor

[John Sprung]

We've been using the Panasonic consumer plasmas with CineTal Davio boxes ahead of them. Calibration using a probe....





-- J.S.

[Justin Cary]

We've been using the Panasonic consumer plasmas with CineTal Davio boxes ahead of them. Calibration using a probe....

John, How much does your Panasonic + CineTal Davio setup run? I'm struggling with the same thing everybody in today's market is... We have access to the biggest cheapest flat screens at any electronics store on the corner but can't rely on any of it. I'm currently shooting a short film with delivery as 2K DPX files and I'm really concerned about getting a good representation of what the client will see on their TVs.

Thanks!

Justin

[John Sprung]

John, How much does your Panasonic + CineTal Davio setup run?

We use facilities vendors, so I don't see those prices directly. I think it's is the $10K - 15K range. Dirt cheap compared with $30K for a 25" Sony OLED, or $50K for a 42" Dolby.

VTP is the place to get them:

http://www.vtpcorp.com/

They may have a branch in Chicago.



-- J.S.

[Justin Cary]

http://www.vtpcorp.com/

I'll check them out. I think I've come across their website in the past when searching for a solution to this issue. Would it be completely out of the question to purchase an AJA Kona 3G or Blackmagic card to send out to a Plasma? $10K is extremely reasonable for the guy sitting in the sit making $100,000/yr grading features and commercials I know there are all sorts of forums about this issue but would it give me decent enough results that I could fake having a $10K system?

- Justin

[John Sprung]

One thing we do sometimes is to take the monitors that'll be used on set to the post facility, and set them up side by side with what the dailies colorist will be using. Write down all the numbers....




-- J.S.

[Steve Shaw]

A bit late to this thread, but the only way to calibrate any display accurately, and especially to match multiple displays, is via profiling software, a probe and 3D LUTs.

The is explained in some depth on the Light Illusion website.

Feel free to have a read, and ask questions if needed.

www.lightillusion.com

Cheers,

Steve