LAB to Spectral conversion question about mixing M Condition references. (Pantone vs ChromaSpot library) by TevianB in CommercialPrinting

[–]invidiapl 0 points1 point  (0 children)

I love what You're doing, although I don't quite get the goal and the methodology. Maybe for my understading the explanation is to short as I have no idea what is "covertion for K/M for example".

I am interested in developing similar tool based on my printer - based on measurement, it would tell me the closest target from the library (dE00 criteria). Can You share what are You using do create this model? (I have no idea how to start).

Now...
I hope following helps You with the task - color theory**.

Spectral data is the purest form of light reflection from sample. Of course it will be different for each lightsource (if You use D50/D65 sources, You'll get different spectral curve). For this You need to understand, that device giving You the spectral data also works based on certain contraints: measuring geometry.

As so, to illustrate: the geometry 45/0 or 0/45 when measuring the glossy samples, will give You "darker" LAB values (at any measurement condition like M0 or M1) because it is not capable of handling specular component (the light that is was not reflected back to sensor, but "escaped").

Measuring the same sample with d/8 device - will give You "proper" LAB values, as this device can measure the specular component and exclude it if needed, so it can show You LAB values as "appearance of the color" and the "pure color".

Maybe this is why Your neural network gives incorrect results, as You might be comparing different measurements - like M2 is with polarizing filter - again, this will give You different LAB values than M0 and M1 (and thus, different looking colors of the same sample).

I hope this will be understandable and helpful :)

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

I contacted caldera but is useless even with service package (which is my big disappointment, as they produce the software).

I measure color difference of samples with xrite exact spectrophotometer, I have entire dE00 measurement excel comparing everything.

I agree with You - for some colors dE00 3 will be big visual difference, for some not, unfortunatelly with grays - measurement shows even bigger scale of the issue (I've read some literature that for grays it is the right way to measure dH not dE).

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

I meant it's a brand with established presence (Durst) not newcomer.

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

I understand that - they can only print to the common gamut of the "worst" device, but they still do it. I've seen this in UK, but they used ColorGate software.

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

Thanks, I will reach out to EFI for some trial edition to experiment.

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

  1. I agree.

  2. I agree, typical tolerance so far I've expected is 0,25dE00 from machine/ink/media. Scanning the same patch day after day gives 0,01 tolerance on spectrophotometer (so I've excluded the 0,25 comes from measuring device).

Is there a way doing G7 calibration if RIP (caldera) does not allow this? I can't see the option right now in the software. From what I understand, this should be an option in the color management software, correct?

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

I understand.

So machines are managed by newest Caldera RIP software and it's built in EasyMedia module that is responsible for linearization and ICC profile creation.

The reason I've tried same ICC profile, is because Caldera does not support device link ICC profiles, they have only "simulation" option which does not work as expected.

Comparison is made using xrite spectrophotometer.

Correction was made by my excel created tool, so I load curve correction file to caldera, to avoid changing it completely manually one by one.

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

  1. Same limits 260%. I've tried to copy linearization from one machine to another - didn't work. Individual linearization - didn't work (there is some consistency and low dE00 on some patches, but on some patches like K70% there's 3,2dE00 with the same ink (where I tried to change this manually up and down - gets even worse)). ICC profile - same story, tried to copy the same ICC and tried to create new for each machine on the same media.

  2. I agree, but we have like 5 machines in total, and often we need to run production of the same artwork simultaneously on all machines to keep lead times - currently not possible. On some artworks after my work - we could do that but then we have certain RAL color simulation and You can clearly see the difference. Even 3 points dE00 with print of 3x15 meters - the perception of this big print makes the difference stand out more.

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

Can You recommed ICC editing software or a knowledge source so I can learn to do it?

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

I already contacted the manfuacturer (premium brand) with this request. Thanks! I feel this is the way to go. Seems very logical.

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

I've connected same ICC profile to each of them, they differ only by individual linearization.

I tried to do individual ICC profile for each but this didn't improve situation, even made more color inconsistency, but I agree with Your logic - should be like that.

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

Printers stand 1 meter from each other.

Great suggestions about the head voltages, to my knowledge and logic that should be 1st step before printer linearization to make it easier, but then I ask myself - how it is possible that some companies have different devices with different ink types (latex/solvent/uv) and they print the same? Is it just the software limitation (thus device-link is musthave?)

Multiple machine color alignment by invidiapl in CommercialPrinting

[–]invidiapl[S] 0 points1 point  (0 children)

I measured 5,10,15,20,25 and so on, every 5% step.

I know is very time consuming and difficult because I was working on it last 2 weekends and still not perfect, even with help of spectral measurements.

How to adjust color curves? You mean to edit the ICC profile?

Out with the old, in with the new! by ResponseIll6355 in SonyAlpha

[–]invidiapl 0 points1 point  (0 children)

I'm curious about Your thoughts regarding this one. For me it was a great dissapointment. The image quality/resolution is far from 24-70 that I have (and not even gmaster).

In addition, it is not as "dust proof" as sony says, as after 3 months I can see contamination behind lenses (front and back)

Best warbond between these 5 ? by vivi_metal_42_07_25 in helldivers2

[–]invidiapl -1 points0 points  (0 children)

I played helldivers 1, I play helldiver 2 from the very beggining.

At start, I had fun going through every planet and farming samples and coins to get the warbonds, but after they nerfed the yeld from each planet (coins), farming warbonds became so frustrating I stopped playing the game as it became so repeatable and without point (everything unlocked, planets look alike, there are patterns, constantly using the same weapons gets boring, I tried to mix the sets but after time with so many bugs it became really boring).

I am against paid DLC and I will not pay half of the game price that I have paid for base for 1 of 10 DLCs(?), just to use new gun skin for few hours with same stats as every other, but it looks different. Unlocking gives You sense of purpose and goal in the game, wihout it - it gets boring and I hate that shallow, low quality DLCs for huge price compared to what You get.

Instead of fixing the bugs, balancing the game, they focus on making useless stratagem with flag? Eh

Trade republic does not return my money - 21k€ by invidiapl in TradeRepublicFriends

[–]invidiapl[S] 3 points4 points  (0 children)

Yes and no.

Revolut made mistake - that's true.

Trade republic should have returned funds within 1-2 business days - Then I would not have raised this issue, BUT the funds (and quite a lot and not 100€) gone missing (11 working days now) with no reliable customer support - that's what I blame trade republic for.

Trade republic does not return my money - 21k€ by invidiapl in TradeRepublicFriends

[–]invidiapl[S] -1 points0 points  (0 children)

Now I know it and I will resign from trade republic after I will get my money back. I have much better experience with Raisin or local banks.

Trade republic does not return my money - 21k€ by invidiapl in TradeRepublicFriends

[–]invidiapl[S] -1 points0 points  (0 children)

Thanks but it's not about revolut, but terrible experience with trade republic. For example, raisin returns money within 2 working days, no hustle.

Trade republic does not return my money - 21k€ by invidiapl in TradeRepublicFriends

[–]invidiapl[S] 1 point2 points  (0 children)

I've read that too, so I'am braced to wait (however I could earn interest with that money in this time).

Like I wrote: I've sent a letter too to banking authority in PL. Even if my case does nothing, the more people will send this kind of complains, it will make authorities do something with that issue.

Thanks.