Where is the “Keep Light On” button on Scan Tab?

[Alec246]

Hi

just discovered NegPy can control my Scanlight v3 for trichromatic capture, which is amazing.

However i am unable to actually use it because after calibration, the light goes off, and even when i click LiveView, it stays off, which is weird it should come on right? and there should be a keep light on button according to Readme which is now here to be found on my UI, so I cant see the frames to position it before scan.

Anything i am missing?

thanks!

[seanharding]

It should stay on in Live View, so if it's not, that may be a bug. I'd be curious to hear more detail, if you're able to reproduce that consistently.

The button for keeping the light on was just added recently and may not be in the release version yet. You'd need to either wait for the next release, or pull down the code from github to get all the latest stuff. I'm guessing there will be a release build fairly soon, but @marcinz606 decides that and I don't know what his plans are.

[Alec246]

Appreciate the help Sean!

Yeah I assumed it was a bug. To reproduce it isn't hard, I will make a Calibration Preset for Tricromatic, Light works fine. Then if I click Live View, the Light stays dark, but the lower value of RGB From Light I assume it is, had a very low value, but non zero. If I click Turn Off Light, Nothing changes in terms of light, and the RGB Values goes to 0.

I own the ScanLight V3, not the V4 which is what is used by the NegPy dev, so it could be it, different API? V3 doesnt come with the trigger to sync Camera and Light, only the PC Web Control for Individual Intensity of RGB.

I will see if I can make a build of the newer stuff on the branch myself

[seanharding]

Oooh, yeah. I didn't catch the version difference. That may have something to do with it. I don't have a v3 so it would probably be hard for me to test/fix, but maybe you can take a look or perhaps there's someone else in the community with a v3 who can try.

[kurtwindisch]

FYI #1385 and #1403 are the fixes that went in just a couple days ago when I noticed the behavior outside of Live View. You are seeing the button in the GitHub documentation because it shows the latest version, but the binary release doesn't include the feature yet. If you run from source you will get the new button.

Regardless, something is wrong if the Light does not stay on while in Live View. I have not had this problem with my Big Scanlight but will confirm with it and check the code regarding the v3.

[kurtwindisch]

@Alec246 Have you tried updating the Scanlight V3's firmware using the Scanlight Control web app (Chrome recommended): https://jackw01.github.io/scanlight/automation/app_bsl/dist/index.html

Info on firmware updating: https://github.com/jackw01/scanlight/blob/main/v4.md#firmware-updates (v4 but maybe applies to v3 also?)

[kurtwindisch]

Also there may be a bug for v3 users:

The light stays dark in Live View because the app sends it white, and a v3 has no white LED. The same code is in 0.63.0, so it predates Keep Light On.

But this should not impact trichrome scanning. Some questions to narrow it down:

1. After you complete the calibration, are there any errors shown? What does the status show for the Light's R/G/B or W levels sent?
2. Is the light still shown as connected / GREEN after the calibration?
3. Can you try it with single capture broadband calibration instead of trichrome? Does the light still stay off?
4. Manual preset, all sliders at 255: this should light. Then lower all three to about 10 to 30. If the light goes dark somewhere in that range, that's the v3's visible floor.

Thanks!

[Alec246]

Hey Kurt, thanks for the list on suggested tests for my ScanLight V3, here it goes:

NegPy as it opens, after successfully recognizing both my Nikon Zf and ScanLight V3

Preset 500T Trichromatic Enabled, Live View Open, All Dark

Manual Preset, Light goes On

Single Capture RGB Mode, Live View Turns On Light correctly, everything works as it should

I think you are right in your last sentence. It seems the Trichromatic Preset Enabled Engaged the RGB Light to very very low, basically Off LEDs when I open LiveView, and this doesnt happen with Manual Preset or Single Capture Mode for whatever reason

Hope this helps!!

[kurtwindisch]

Thanks the info! Can you play with the sliders in manual mode and find the minimum floor values that bring the light on? In your trichrome screenshot you were at R22, G23, B19, which may be below that floor. If we can establish the minimum, I can push some fixes (maybe get them into tomorrow's release).

Turn on Live View in manual mode and set R, G and B all equal. Step down through 100, 80, 60, 50, 40, 30 and note the lowest that still lights. It's also worth one pass with a single channel at a time, since the LEDs could have different thresholds.

Also what does Negpy report as the model of your light when you hover the green "Light" in the scan panel?

[kurtwindisch]

@Alec246 I have pushed a PR for this. It addresses the known issues via:

1. A floor on the minimum light channel values for scan light v1-v3. That minimum right now is 115, which is the lowest value you showed above, but it can certainly be tuned lower to avoid blowing out the Live View. See my questions on the previous comment. I can update the floor value later when you are able to provide it.
2. The unsupported white light options should not be shown.

See the comment above for questions that I'm still looking for your feedback on.
Thanks

[Alec246]

Hey Kurt just to let you know i am out of the country until next week, unable to test your new build. As soon as I am back i report how it goes. Appreciate the effort!

[kurtwindisch]

Does anyone else here have a scanlight v3 that can report back with the minimum levels that bring each channel on?