BasICColor DISCUS Owners thread - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 22 Old 09-23-2017, 01:34 AM - Thread Starter
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BasICColor DISCUS Owners thread

Although they've been out for a few years there doesn't seem to be a good repository of information about the BasICColor DISCUS colorimeter. I've just picked bought one to use with Lightspace.

So I'm creating this "Owners thread" to collect anything of use. Please contribute experience, useful information, hints, tips and questions for other owners.

The next post will be a repository for links to helpful information.
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post #2 of 22 Old 09-23-2017, 01:35 AM - Thread Starter
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Useful links

BasICColor: Product page / Datasheet / Manual / FAQ
Light Illusion: Info Page - reading presets vs patch luminance particularly useful (bottom of page)
Spectracal: Datasheet

Reviews:
Northlight Images: Review
ColorWiki: Review
Dry Creek Photo Sensor Comparison / VS i1 Display Pro
Bruce Percy: Blog

Useful Information
Speed and low light capabilities thread - AVS Got a bit off-topic, useful posts from Manni01: Post 31 / Post 48
Experience with JVC X-series - AVF

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post #3 of 22 Old 09-24-2017, 12:15 PM - Thread Starter
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Here are my own first impressions of the BasICColor DISCUS meter after receiving it and a couple of nights playing around. Up until now I've been using a couple of i1d3s, with an i1pro / i1pro2 as a reference. Please note I don't have any high-grade meters; but my i1d3's and the i1pro/2 all agree pretty strongly with each other. Mainly I calibrate my JVC X30 projector, though I also calibrate my old Sony CCFL daytime viewing TV.

Bought from Light Illusion Friday 15/9/17, meter was dispatched by BasICColor directly from their German office on Monday. Arrived via UPS on Thursday, well packed.

On opening the box I was greeted by a "Certificate of Performance" (valid for 18 months from date, which was the day of dispatch of the meter from what I could see). See copy of the certificate (S/N removed). Judging by the details on the certificate, the meter had read around ~1800 patches across 4 sample monitors, simultaneously with a CAS140CT lab spectrometer. The kind of numbers on it look pretty impressive. The meter and hockey-puck and tape counterweight were well presented in a custom foam insert, which is glued in the carton.

On removing the meter from the insert I immediately thought "this is a seriously engineered piece of kit". The finish was flawless, with a beautiful action on the rotating base plate which switches between closed / calibration dark measure, ambient light diffuser and open. The laser is also exposed in both ambient light and open positions.

The meter body is threaded at the "top" to take a small knurled thumbscrew, which attaches it to the tape / hockey puck assembly for contact measurements. The "bottom" of the meter has a 3/8" threaded hole, into which a 1/4" removable reducer is fitted. These two arrangements do have a couple of limitations.

The 1/4" thread reducer isn't completely flush with the bottom of the meter, which coupled to the circular nature of the bottom means that attachment to a tripod quick release plate is a little fussy, with limited contact. On my plates (Manfrotto) the reducer would bottom out before the body of the meter was tightly gripped by the rubber mat on the quick release plate. I remedied this by building up the surface of the quick release plate a little with some cloth tape. It only needed a couple of layers.

The hockey puck assembly is a nice idea, but I found that it doesn't actually work on the only TV I have - an older Sony "Picture Frame" style KDL32E4020. This has an (abnormally) deep Aluminium bezel assembly (probably 12-15mm from the bezel to the screen surface). In fairness my i1display pro is not super secure on it either, but it does just about sit flush. The i1pro2 mount works great on it, however, so clearly a good universal mount can be designed to cope with such sets. In any case I'd probably limit myself to non-contact measurements on a tripod, so it isn't really a big deal.

Connecting the meter up it worked straight away with Lightspace HTP (the minimum license needed to do 3DLUT with DISCUS). On connection you are asked to rotate the cover to take the required dark measurement, less than half a minute later it lets you know it is done, and you rotate the cover to open the lens. The Lightspace "Enable Visual Feedback" button toggles the aiming laser on / off (the manual explains the offset from the measurement centre).

My findings on performance of the DISCUS mirror those of @Manni01 .

Straight away when doing the contrast measure off screen you could see this meter was effortless in reading dark patches, and it felt quick in operation. There are 4 preset modes for taking readings, with either "short" or "long" integration, averaging a lower or higher number of measures. In preset 0 - the fastest - it was easily able to read the JVC black at <0.003cd/m2. In doing a 21pt grey + primary sweep you could clearly see the lamp colour temperature bias coming through in the very dark patches. I'd not easily been able to make this out previously on the i1d3 meter - the readings in the very lowest 5% patches would be all over the place usually, and getting a reading at all from black was challenging.

Preset 0 readings took 4m07s to read the 81 patches for 21ptGS /RGB. This was with a 0.5s patch delay. With 0.75s reads configured on the i1d3 this could be completed in 3m05s with the same delay. However on the i1d3 the black reading was miles off (about 3 times too large), the dark patches seemed to only approximately be reflecting what you'd expect to see as a lamp bias (the x,y varied quite a lot from what you'd expect) and the resulting measured RGB separation up to around 15% white had a noticeable difference between the white patches and the expected RGB values. On the DISCUS the RGB separation was basically perfect down to 0.

Increasing the i1d3 reading times (either using the new beta auto integration time, or setting a large fixed time) would yield better results - but the reading time would increase to somewhere between 8 and 9 minutes, and the results still didn't look very clean at the very low 0-10% end.

A larger optimised patch sequence of approximately 4000 patches took a little over 3hrs to read on the DISCUS.

So I think re: reading times; it is safe to say that you can drive an i1d3 faster than the DISCUS, the dark readings will definitely be poor. The quickest reading mode on the DISCUS yields slower performance than the fastest possible on the i1d3, but you gain dark readings that look very sensible. Trying to get good dark readings out of the i1d3 and you rapidly end up with much worse reading times than the DISCUS, and still don't have the quality of dark readings of the DISCUS.

@Manni01 thought his meter was faulty due to the discrepancy to his spectro - and having played with the meter I'm not sure his was particularly bad to be honest. A post in the ArgyllCMS mailing list from a previous DISCUS owner says he found the same ( https://www.freelists.org/post/argyl...DISCUS-meter,6 ). None of the built-in presets seem to be particularly good matches for my i1pro2 when measuring the "probe matching" patches for my Sony CCFL or JVC X30 projector, whereas my i1d3 meters did correlate strongly.

There is an extensive database of (mostly pro graphics) monitors which have detailed matching done, with matrixes built in, and some "generic" LCD profiles for various backlight types. A utility allows you to swap in additional calibrations (though these are called user calibrations, I'm yet to find how to create them myself). The matrix upload utility came with some "LCOS" matrices, but these also didn't seem to be great matches for my JVC.

Of course this doesn't matter if you have an i1pro/2 spectro for profiling (and I can't imagine anyone going for a high-end colorimeter doesn't already have a spectro). I have the i1pro so I'll gladly take the improved dark performance in exchange for creating my own profiles.

One other little gripe is that there isn't support for the device in ArgyllCMS. These days I mostly use Lightspace (and CALMAN is also supported), but it would be nice to have the option to use the meter within HCFR / displayCAL / etc, which ArgyllCMS support would facilitate.

In summary - I think from what I can tell that if you want quality very dark readings this is probably the only game in town until you get up to the dizzy heights of the CR100/K10A meters. I'm not going to be able to justify one of those for my hobby purposes any time soon - even this was a bit of a stretch - so the above are probably all best thought of as acceptable compromises given the performance, rather than issues.

In a bit of daytime downtime I made myself up a little calibration kit with the i1pro2, DISCUS and an i1d3 for good measure, using the great value Peli-knockoff MAX430 case ( https://www.amazon.co.uk/Max-MAX430S...words=max+case ). See attached. Really good case for the money, made in Italy no less.

I'll try and upload some useful data at some point.
Attached Images
File Type: jpg _20170923_080230.JPG (573.6 KB, 74 views)
File Type: jpg _20170923_070816.JPG (1.00 MB, 64 views)

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post #4 of 22 Old 09-30-2017, 12:23 PM - Thread Starter
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In case anyone is interested in timings for profiles; a 21^3 cube with 0.25s delay per patch, and drift patches every 20 patches (9725 patches total) takes just over 5 hours in preset mode 0 with a JVC DLA-X30 display going between 0.002cd/m2 and 60cd/m2. So averaging a reading every 2s all-in over this luma range.
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post #5 of 22 Old 10-24-2018, 05:00 AM
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What in your opinion is better to buy nowadays as a daily use colorimeter? Basiccolor Discus or a new i1dipslay pro oem with 2000 nits range? Assuming you still need a xrite pro2 spectro as a reference.

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post #6 of 22 Old 10-24-2018, 05:35 AM - Thread Starter
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What in your opinion is better to buy nowadays as a daily use colorimeter? Basiccolor Discus or a new i1dipslay pro oem with 2000 nits range? Assuming you still need a xrite pro2 spectro as a reference.
For Discus you absolutely need a spectro; for i1display pro you may be OK(ish) without.
If you need to use software based on the excellent ArgyllCMS (HCFR, Displaycal, etc) then the decision is made for you - there is no Discus support.

Discus readings of very dark patches are without parallel in the sub $1K region. Often if I just want to do a quick reading of something I'll grab the i1d3 as it is a little more versatile - no need to do dark cal step, can set very fast integration times so long as you are conscious of what you are doing.

If Lightspace is your poison then for 3DLUT Discus condemns you to the much more expensive Lightspace HTP license, which has some nice bells and whistles but is a lot more money than HTL.

If I could only have 1 meter I'd get the i1d3; in fact I'd probably always want one to be able to use the tools that don't support Discus. If you can afford the extra meter and software licenses then the Discus allows you to add useful readings in regions the i1d3 simply cannot reach.
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post #7 of 22 Old 02-16-2019, 09:26 AM
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How is everyone profiling their Discus? Do you have a jig or two tripods, or just swap which meter is on the tripod? Is the viewing area/angle the same as the i1Pro2 or do we need to use different distances from the screen?

I'd previously been using the LCOS 709 profile, which I think Manni provided to Basiccolor, with good results (by eye and a C6 trained with the i1Pro2, using the diy jig from the two Spectracal mounts) but I'd like to profile to see if with the 4k JVCs there is a difference.
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post #8 of 22 Old 02-16-2019, 11:48 AM
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Originally Posted by dlinsley View Post
How is everyone profiling their Discus? Do you have a jig or two tripods, or just swap which meter is on the tripod? Is the viewing area/angle the same as the i1Pro2 or do we need to use different distances from the screen?

I'd previously been using the LCOS 709 profile, which I think Manni provided to Basiccolor, with good results (by eye and a C6 trained with the i1Pro2, using the diy jig from the two Spectracal mounts) but I'd like to profile to see if with the 4k JVCs there is a difference.
These profiles are better than the old factory presets, but there don't replace a proper profile made in situ with a spectro.

I use a single tripod with a dual mount. In the past I used to use two tripods to match the viewing angles (they are different, I had the Discus at 2ft and the i1pro2 at 3 feet) but frankly as I use full patterns (to match the size of internal patterns of the JVC used during the autocal) I've stopped as it makes no difference except it's a real pain.

I highly suggest, when profiling, to set the Discus to high average, long integration and to enable the low light handler of the i1pro2 set to 30 samples and a trigger of 500nits (which means likely all measurements!). That way, the profile is good every single time, especially if you run a dark cal on the discus and a white cal on the i1pro2 just before profiling, as they both drift even within their calibration window.

If you have any JVC 4K specific question, please post them in the new calibration thread (see my sig). I've just answered bobof there and mentioned the different meter profiles I use for the Discus with the JVCs. I also posted detailed measurements and first impressions of my rs2000 that you might find interesting
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post #9 of 22 Old 02-16-2019, 12:19 PM
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Thanks Manni, and will do.

I've seen those dual mounts posted before, I can't recall who sells them, and may look into that. I think they were the price of my decent tripod though, so I'll probably just pick up another of those locally
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post #10 of 22 Old 03-22-2019, 10:00 PM
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Hi Everyone.

may i ask there is good points out BasICColor DISCUS is better than Spectracal C6 HDR-2000 besides BasICColor has 500 cd/m2 better than the other.

My i1Display pro bought on 2012, thinking to upgrade it.
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Shortly: With Discus you get more consistent measurements in low light reading (0-5%), for all the rest you have the same i1D3/C6 readings but (really) slowly &#x1f609;
Let’s say that Discus is the child of a Klein k10a and a turtle.
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post #12 of 22 Old 03-23-2019, 04:11 AM
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Remember the C6 is just an i1D3 OEM.
No hardware/firmware difference.

The Discus is very good, but lacks a 'sync' function.
That is why it can be slow on some display technologies, as a long integration time will be required for stable readings.

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post #13 of 22 Old 03-23-2019, 05:31 AM - Thread Starter
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Originally Posted by Light Illusion View Post
The Discus is very good, but lacks a 'sync' function.
That is why it can be slow on some display technologies, as a long integration time will be required for stable readings.
A good example of this is that at 24p the Discus returns inconsistent, unstable readings from JVC projectors in Mode 0. Mode 2 is required to get stable results.

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may i ask there is good points out BasICColor DISCUS is better than Spectracal C6 HDR-2000 besides BasICColor has 500 cd/m2 better than the other.
.
I like my Discus. I've listed the niggles and benefits above. Take particular note of the requirement to use a spectro to profile it. With other meters the built in modes are useful for many home displays. The Discus doesn't have any built in tables as far as I can see that are of any use whatsoever with consumer TV or lamp projectors, they are all miles off. So a spectro is absolutely essential.

If you don't have a spectro, don't bother with Discus, your results will not be very good at all.

What displays are you looking to calibrate with it?
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Originally Posted by bobof View Post
A good example of this is that at 24p the Discus returns inconsistent, unstable readings from JVC projectors in Mode 0. Mode 2 is required to get stable results.

I like my Discus. I've listed the niggles and benefits above. Take particular note of the requirement to use a spectro to profile it. With other meters the built in modes are useful for many home displays. The Discus doesn't have any built in tables as far as I can see that are of any use whatsoever with consumer TV or lamp projectors, they are all miles off. So a spectro is absolutely essential.

If you don't have a spectro, don't bother with Discus, your results will not be very good at all.
Well noted. then i will not consider DISCUS agin.

Quote:
What displays are you looking to calibrate with it?
Here is what i done recently, you may check it.

https://www.avsforum.com/forum/139-d...l#post57799906
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Sorry to jump in like this but did any of you discus owners used it on LG Oled tv ? Does it work ok? Any recommendation?

thank you
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As far as you use integration time settings on 2 or 3 I can’t see any reason for it to not work properly.

A/V Chain: Pioneer PDP-LX5090H, Pioneer VSX-921, Panasonic DMP-BDT260EG | External LUT box: Entertainment Experience eeColor | Softwares: Light Illusion Lightspace HTP, Portrait Displays CalMAN Home Enthusiast 2018, HCFR, DisplayCAL | Probes: x-rite i1 Pro 2 - i1 Display Pro OEM B-02, basICColor DISCUS | Test Pattern Generator: DVDO AVLab TPG
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post #17 of 22 Old 04-07-2019, 01:20 PM - Thread Starter
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Originally Posted by adolfotregosa View Post
Sorry to jump in like this but did any of you discus owners used it on LG Oled tv ? Does it work ok? Any recommendation?
Just make sure you have a spectrophotometer / spectroradiometer available to create 4 colour correction matrices. Without it the Discus won't do you much good.
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Yes I have i1pro2 for that.

Thank you for your input, I will try to buy one to replace my i1d3. I am not confident with very low light readings of the i1d3 and the discus is the only choice and even it is expensive.

The joy of calibrating...
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Yes I have i1pro2 for that.

Thank you for your input, I will try to buy one to replace my i1d3. I am not confident with very low light readings of the i1d3 and the discus is the only choice and even it is expensive.

The joy of calibrating...
Yes, there is certainly nothing that can compare for low-end reading capability outside of the "big boy" meters like the Klein and Colorimetry Research units.
What software are you using?
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Yes, there is certainly nothing that can compare for low-end reading capability outside of the "big boy" meters like the Klein and Colorimetry Research units.
What software are you using?
Very nice to hear because I really hope to improve the low readings.
LS-HTL, why?
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Very nice to hear because I really hope to improve the low readings.
LS-HTL, why?
Good choice in LS. Just bear in mind HTL won't work with Discus. You'll have to upgrade to HTP.
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I always mix the names. I meant LS-HTP.
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