3D LUT Calibration

I'd be interested in a standalone device (box) that allows me to fully adjust and calibrate the greyscale at at least 11 points, gamma at at least 11 points, and has a WORKING fully functional 3D CMS (color management system) for adjusting saturation, hue, and lightness of all primaries and secondaries.

I'm not too sure what a LUT would do. I presume you would connect your light meter, colorimeter, spectrophotometer, etc. to your computer or this suggested standalone device and then it would read and plot your current settings, where you could then go into the device and tell it where to take the adjustments to (the calibrated ideal), and it would automatically apply the differences.

This would be fantastic in theory. How is it in practice though?

Is there clipping and banding and distortion and video processing problems/introduced artifacts due to this processing?

I hope I'm not misunderstanding something. :P

I believe the Video EQ Pro uses a 3D LUT to achieve calibration. There is a separate thread about this device, though support seems a little sparse, I've managed to get my HD350 setup very well using a rented i1Pro giving near 'perfect' dEs in greyscale and colour gamut.

However, due to the chance of a good deal I'm now getting the new Lumagen Mini3D to replace my Edge/VideoEQ Pro combo. One of the many reasons for this change is that I'll be able to do a closed loop calibration using Chromapure to control the test patterns and the settings in the M3D. There is also much finer control of various other controls such as aspect ratio and masking, but these aren't relevant to the calibration discussion. From your posts so far I get the impression that you believe that a 3D LUT is the best way to calibrate a display, so I wonder what you make of my 'upgrade'.

EDIT: Link to VideoEQ Pro: http://www.spectracal.com/newproduct...ZHYGMHPDQ&Mx=6

I think the issue here is that products like Lumagen already have a strong following and offer great support. You'd be coming in as a 'new boy' so you have an uphill struggle convincing buyers that your system is better than what's already out there. If you follow the VideoEQ threads you'll notice that questions go unanswered for long periods which is also one of the reasons I'm moving over to Lumagen. If you don't provide the kind of support offered by firms like Lumagen, then buyers will quickly lose patience and you'll get a bad reputation. I'd imagine it takes some considerable investment of time and money to build up confidence, so not something you can achieve overnight.

There is a separate thread discussing how linear the Lumagen solution is compared to the built in CMS in the popular JVC projectors. The general concesious seems to be that the Lumagen is more than good enough, so it's going to be a hard sell convincing people that your product is superior to one that doesn't seem to have obvious issues. (A small hint that critising competing products doesn't come across very well, you have to win by your own merits IMHO). There are countless calibration reports posted using Lumagen VPs that show near 'perfect' results (ie dEs below what is considered detectable by the eye). Professional calibrators are very familiar with the existing products, so you'd have to convince them that learning a new process is worth their while. They'd have to be convinced that whatever your USP is that it would translate into quicker/more accurate end results than they currently manage.

Simply posting a link to your website isn't going to win over potential buyers either, you need to explain why your 3D LUT is better than what is offered by VideoEQ, Lumagen et al. I still don't understand what the difference is between what you do and what the VideoEQ does as that is refered to by them as a '3D LUT' as well. Simply saying that it isn't based on a 3D calibration might be obvious to you, but as your potential target market it isn't to me.

Pricewise, the VideoEQ after importing into the UK works out around £1000 IIRC so is your product something that would be comparable to this? How much is the software likely to be as products like Chromapure are available for around £100 IIRC or £240 if bought with a calibrated meter. It might be that in the professional market you can charge higher prices for these products and services, but in the consumer market price (unfortunately in some cases) seems to be king.

I hope that these comments/questions don't come across as too negative, just trying to give you some feedback from part of your target audience. You need to be prepared to answer these types of question when dealing with non professional end users, so I hope it gives you a feel for what we expect.

I can't speak for others but my main problem with "3D LUTs" and "4913 points on a cube" and most everything you're talking about make very little sense to me.

The Light Illusion website seems like it has information for sure, but I can't seem to find a basic synopsis on some kind of main page that tells me what a LUT is and why I need one.

I don't know if my earlier question was answered, but if I can get great calibration results from an external device and have full control over the greyscale, gamma, and color gamut, then I'd personally be willing to pay around $500 USD for something like that.

I don't want "extra" features or forced packages or anything like that.

Like I mentioned in another thread, I'm planning on buying an iScan Duo so that I can have those calibration options. The "problem" for me though is that in order to do that, I have to buy all the video processing technologies built in the device as well.

I think the video processing is great and I know I'll love it, but I don't want to HAVE to pay for it to get the features I want.

IF you can (in a VERY basic manner) show me how a 3D LUT or ANY device you can offer can provide me with just the calibration controls, then I'd be HIGHLY interested and way more than willing to pay.

Am I right in understanding that you do the measurements for this LUT rather than the customer? In this case you'd be coming to site to calibrate the display (especially in the case of a projector)?

I know how long it takes me to measure and adjust 11 point grayscale and 18 points in the CMS. I can only image that 4913 points would have to be done automatically or it would be very time consuming and liable to operator error if performed on a DIY basis. I can at least understand how measuring at many more points would increase the calibration accuracy, whereas with something like a Radiance you only measure and adjust at 11 points greyscale and 18 points on the CMS settings. Lumagen have hinted at being able to adjust at different saturations, but I'm not sure how likely this is. However, as I mentioned before those that have measured linearity of the Radiance seem to show that the dEs are within what our eyes can detect anyway. While these extra points in the 3D LUT would result in a more technically accurate result, I wonder if this would be visible on the display?

Yes, that helps...apart from that I'm already commited to my new Lumagen Mini3D order. It's not an issue as I'm buying this for other purposes apart from pure calibration (anamorphic lens scaling, masking and general upscaling among others) plus I've been an ealry adoptor before and sometimes it's nice just to stick with something better known. However, I hope you do manage to get this product off the ground as if nothing else it will keep the existing options on their toes.

I'm just feeling less intelligent with each new post here from you guys.

I tried reading the like you provided (Light Illusion) and I think I grasp some very small portion of it, but it's all so technically written that I don't fully understand.

With your device, could I control my greyscale, gamma, and colorspace and gamut?

What equipment/software would I need?

It seems I would have to buy your external box you're talking about developing and then I would also have to buy the Light Illusion CMS, correct?

How much would something like that sell for?

If you made a box, I know I would want one with PLENTY of inputs and outputs (composite, s-video, component, dvi-i/d, hdmi, etc.), or at least the "important" ones. It would be especially nice to be able to set different calibrations for each input/output.

I'd certainly pay for that device.

You have my attention. Is this in the ballpark?

LightSpace CMS - Main Component £449.00 UKP
LUT Box $500

I hope this isn't an issue for me to post this on the forums (can't imagine why though...) but I want anything I bring up to be seen by anyone so that someone else may be able to chime in, or ask questions of their own.

I really want this system if it's affordable and reasonable and can truly do what I think it can. *crosses fingers*

------

"Hey Steve!

This (if you didn't already notice) is "Kamui" from the AVSForums and I've been messaging you (or someone from your company ["Light Illusion"]) on there.

I have to say that right out of the gate: If your customer service is anything like your response times now and your friendliness so far and your seemingly willingness to help; you'll go a very long way! I really do appreciate any help. I feel badly though about not knowing enough about what you've been discussing about 3DLUTs, etc.

From what I've seen from your site and from the software I downloaded, it looks like something I really want. I'm extremely interested.

My only "qualm" about the software so far is simply that the radio buttons on the top of the screen are a bit small and that means next to nothing. Haha. Seeing the 3D cube and being able to move it around was really fantastic and I think helped me understand better that you might be suggesting I could independently adjust all of those points if I wanted (R,G,B, at any luminance level charted) or simply do it automatically.

Also, being able to simply chart my current display and simply telling the software where I want it to end up and the software doing it automatically is an amazing concept.

Take a look at the DVDO iScan Duo video processor. If you had the inputs and outputs of that and the ability to seperately calibrate each of them... You'd have a HUGE winner on your hands.

If you're talking barebones for home theater... Have one HDMI 1.4 input and one HDMI 1.4 output.

I really hope this helps you and I especially hope this helps me, if it is indeed what I'm thinking it is!

Also, one last thing... Do you HAVE to have a highly accurate meter (I would think you would) to do this type of calibration?

I mean, what would happen if someone tried to calibrate this way with the (very popular on these forums) i1Display 2/LT colorimeter?

-Brian"

I also have read through the website explanations but am still a bit confused as to how this all works. The information is still quite technical. I have a ColorMunki Spectrophotometer. It appears that your software doesn't support this meter. I have been learning calibration as a home enthusiast for the past 2 years. My learning curve remains very steep and I greatly appreciate the professionals on this site that have taken their time to help me and others like me to further our understanding of this trade. Calibration for me and I'm sure many others is a hobby. We enjoy learning and the do-it-yourself aspect. I'm certain that your audience includes many people like me with a significantly less than professional level of understanding. The sites of the other processors (Lumigan, iScan Duo, etc) are easier to understand how I would use their technology to achieve a better result. If the price point of your proposal is favorable, I would also be interested in hearing more about this technology and device. Please bring your presentation down to a more basic level so that we can understand it. What is the device specifications? How does it work? How do I control it? Cost? Etc. If your device was listed on Amazon or similar site, how would you list it, describe it, and sell it? Thanks.

-Mark

Thanks Mark for succinctly saying what I was trying to get at. Haha. I agree with you 100% and am in exactly the same boat.

I can't see how it would make much sense to have a box around 500 but have to pay at least twice that for a supported meter.

I would think adding support for the i1D2, colormunki, spyder, chroma 5, and other less expensive meters would really launch this potential product.

Granted the level of accuracy wouldn't be near that of the more expensive meters, but the people who purchase these meters, do so with that understanding already.

I can't see any reason why support for these meters shouldn't be there.

Here's another e-mail snippet from Steve at Light Illusion:

"It would, in theory. be possible to manually change the points in the cube - but the difficulty in doing that really makes it next to impossible. The operation is fully automatic, which really is the only way to make calibration work correctly.

The one problem with HDMI is there is a large license fee for its use- that does make costs higher - but if that is what is needed, so be it.

I do use the i1-D2 a lot - great for LCD, but plasmas really need a non-contact probe due to their high noise level in the blacks.

Anyway, have a play with the demo and see what you think.
I look forward to hearing more.

And do feel free to post comments on the forum - good or bad!

Cheers,

Steve"

....

and my reply:

"I personally don't feel that HDMI is necessary. I would be equally happy with DVI-D/I. If you could keep the costs down by omitting HDMI, I'd personally be all for it, unless the cost wouldn't be much different.

I understand about the i1D2 meter and it's faults, etc. but I'm just suggesting that if you had support for it, you'd sell a LOT more of your suggested devices (to enthusiasts like myself) than if you didn't."

....

I'm extremely interested if this device is possible for a fair price that wouldn't cost me more than getting an iScan Duo. I personally want to pay for just the calibration features of the iScan and not the video processing, so in theory, this device would do that... Hopefully it's feasible and can be had for a decent/fair price.

Maybe a limited license or limed featureset edition to the software aimed specifically at a home end user if that's possible.

A bundle package with the "Lightbox" :P and you're off!

Hopefully something is possible.

I just wish someone would make a purely "calibration box" for a fair price that's not part of a combination device (such as the iScan Duo and it's processing features).

Do I interpret that to mean all of these options?


449
249
249
599
= 1546 UKP = $2488 USD = YIKES

If you could make a device that simply allows calibration (greyscale, gamma, gamut, etc.) and that was JUST the controls for each section, I would pay upwards of $500 USD for that device.

SURELY this can't be too complicated for designers. It's upsetting that this doesn't seem to exist in a working package.

I honestly don't care (sorry Light Illusion) if it's just 11 point adjustments of greyscale and gamma and a 3D CMS and not a 3D LUT setup with all the advanced calibration features you suggest a 3D LUT can provide.

I still haven't (in a very easy to understand) seen anything that suggests going from what we currently have (as enthusiasts) with the iScan's calibration options (for example) to the 3D LUTs would be a worthwhile "upgrade", worth the MUCH higher cost.

Please PLEASE, if you can design what I suggest, I know that myself and a TON of other people (at least on the forums) would pay in a heartbeat for this device.

That would be fair, methinks, as long as the pricing was sane. :P

I like calling you "Light Illusion"... It's cool! Haha. But Steve, or Mr. Shaw if fine too. :P

The VEQ can operate this way , there was discussion of using the hdlink pro although this seems to have some format issues and didn't support hdmi the last time I checked ,and there are a couple of PC based systems that people have been using notably the Upsilon mixer and MadVR.

I have used 3dlut systems for years notably cinespace and the Kodak display manager.

Artefacts can be generated but its usually a function of the display not having enough contrast range to withstand the lutting.

The colormunki seems a cheaper option than the hubble or k10 to be honest and you can get good results with a spyder3 or D2, contact probes work fine on plasmas.

There was talk of building a lut box ( there are some individuals on here who can and have done so) however the hdmi licensing costs were prohibitive and rolling out a dvi version is likely to be problematic due to the 8bit nature. The software costs for lightillusion would seem to put it beyond the average home cinema enthusiast especially considering there are other mechanisms out there ( the upsilon mixer for example supports many more sensors including the colormunki and multiple color targets and automatic detection of content)

I am also currently in India supervising some hollywood and bollywood films. I am also just about to update the 3d lighting pipeline.

When I spoke to Blackmagic about this a few years ago there were concerns about rounding errors and sound sync going this route.

This is 8bit video and ideally needs to be passed around at 10bit or above to minimise the chance of posterising from a 3dluting process. Compression is besides the point. I was under the impression the hdlink pro would not accept 10bit 4:4:4 yuv input


Getting 7.1 into a HDlink pro from consumer sources is yet another stage of complexity . I believe from memory you have to provide discrete 7.1 pcm to the convertor, You would likely have to go analogue first then into a convertor to provide the right sort of pcm to feed the BM chain. The guys at Blackmagic themselves told me this was likely to be a problem unless provision was made to resync the audio. This is something beyond most HC fans.


The hdlink pro is a fine bit of kit for the money but it doesn't fit into a home cinema environment very nicely. It also misses some format handling that is required for home cinema , 1080p 24/23.976 over the dvi output for example . Although they may have updated it.

I considered it myself ( as I can profile and generate luts in cinespace) but blackmagic actually put me off the idea as it seemed lot of hassle to get integrated successfully and the audio delay seemed to be unsurmountable.

I'm in Mumbai at the moment (have been for over a month) , I spent 3 months in Hyderabad two years ago. I'm in the shadows fixing one hollywood film for the VFX supe on that and I'm the VFX supervisor on a couple of large bollywood films as well as sorting out some color pipeline stuff and giving the artists some theory lectures.