ILD file color vs ILDA port

[uketernity]

Hello

I have a 5w Emma EM-RGB270 laser with SD card slot. I am trying to figure out why I get better color control over ILDA port vs ILD files on an SD card. It seems like when reading from SD card, for the same ILD file I can open on my laptop in Laser Show Gen I get a different colour output.

I created a simple gradient line and output this to an .ild file in format 0, popped it on the card and loaded it into the laser. When displayed, instead of a smooth gradient, it appears as blocks of single colors, red, yellow, green, light blue, dark blue, purple, however when output by LSG via Helios DAC it's a (relatively) smooth line.

I've tested other patterns and colors, and it appears that the ILDA output will mix the colors, whereas .ild file shows up as the "closest" color. If I make an orange shape, it outputs as red via SD card but orange via ILDA.

I know this is a fairly budget laser but it can clearly mix the colors over ILDA, wondering why it might not do it via SD card and if this is a limitation of the .ild format or the laser itself.

Note: first photo is .ild file on SD card, 2nd photo is ILDA. The banding in the 2nd photo isn't as noticeable irl, the camera made that happen.

Any help would be appreciated.

Thanks

[dchammonds]

Hello

I have a 5w Emma EM-RGB270 laser with SD card slot. I am trying to figure out why I get better color control over ILDA port vs ILD files on an SD card. It seems like when reading from SD card, for the same ILD file I can open on my laptop in Laser Show Gen I get a different colour output.

When you drive your projector from the SD card, you are utilizing the projector's internal digital to analog converter (DAC), and it looks like it is rendering a simple TTL 7 color reduction (RGBCMYK). Your Helios DAC has the ability to ramp the individual color channels to create smooth transitions throughout the spectrum.

[uketernity]

Yeah, seems like that is most likely the issue. I assume the only way to fix this would be to replace the internal control boards?
Can you confirm that .ild files can contain more than these 7 colors? I'm a noob and still learning. Thanks.

[dchammonds]

Yeah, seems like that is most likely the issue. I assume the only way to fix this would be to replace the internal control boards?
Can you confirm that .ild files can contain more than these 7 colors? I'm a noob and still learning. Thanks.

I wouldn't recommend changing boards in the projector. Be content with the fact that the laser drivers support analog modulation through the ILD port- some projectors don't.


As for the ILD 0 format, the default color palette is 64 colors, and it consists of a rainbow pattern that ramps into white. All 64 colors are saturated, which means that each has at least one RGB color channel at max while others are ramped. Feel free to post one of your ILD files and I will take a look at it.

[uketernity]

Thanks for the feedback, very helpful.

Attached is an example file and two photos, first is the ILDA with Helios DAC using Modulaser to send the data, second is the .ILD file off the SD card.

Thanks

[uketernity]

Also here is the same ild file exported at version 0 with "alternate palette for format 0" from Laser Show Gen.
Note that Ilda V5 files do not work on the projector.
Ignore the fact that X is mirrored in some of the photos.

[dchammonds]

Also here is the same ild file exported at version 0 with "alternate palette for format 0" from Laser Show Gen.
Note that Ilda V5 files do not work on the projector.
Ignore the fact that X is mirrored in some of the photos.

inf-static.ild uses 55 colors and it looks just fine. The alt version is a little more complicated; I'll come back to that later.

[dchammonds]

ILD fmt 0 allows for the inclusion of a user defined palette of up to 255 colors, but this palette table must be included with the ILD file to render properly accross the board. The "alternate palette" ILD that you posted doesn't include this table, so 'what you see is what you get' depending on the software/hardware you are viewing it on. The interesting thing is that your projector yields a much more accurate color reduction (once the mirror image issue is considered) using the alternate table, and I don't think that's an accident. ILDA goes way back, and there was more than one default palette floating around in early times.


Custom palette tables are known as ILDA fmt 2 Color Tables, and the concept goes back to the dawn of VGA, but it doesn't look like the idea caught on in laser usage from what I've seen.

[uketernity]

Thanks.

Attached is the original ILDA V5 file that gets exported from Modulaser, I loaded this into LSG and then exported at version 0. I don't know if the projector supports any other version but 5 definitely does not work. Perhaps LSG is the issue?

Either way it seems like when reading from SD card it still only displays 7 colors, I am trying to find out from the manufacturer if it uses a TTL DAC or not.

[dchammonds]

Thanks.

Attached is the original ILDA V5 file that gets exported from Modulaser, I loaded this into LSG and then exported at version 0. I don't know if the projector supports any other version but 5 definitely does not work. Perhaps LSG is the issue?

Either way it seems like when reading from SD card it still only displays 7 colors, I am trying to find out from the manufacturer if it uses a TTL DAC or not.

Your fmt 5 file is OK. Formats 4&5 are 24bit color in the current ILDA spec that dates from 2014, fmt 0 goes back to the 80's. From what I've heard, SD equipped projectors can only read fmt 0.


Here's a link to the current ILDA spec, perhaps someone could post it on TikTok so the Chinese can find it and update their equipment.

https://www.ilda.com/resources/Stand...F14_rev011.pdf