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Software Dev / Re: Chronos V0.3.2 Beta - Updated June 25th 2019 with beta-6

« on: August 30, 2019, 05:36:12 AM »

I just noticed a significant lag on the screen update if the overexposure-warning stripes are shown. It appears to drop down to single digit FPS and takes a few seconds to recover even after the bright spot is gone. I noticed this after the screen upgrade, but they can't possibly be related. I have not tried yet if recording is somehow affected.
If needed i can provide a video of the "slowdown" happening.

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Chronos User Discussion / Re: Chronos 1.4 screen upgrade?

« on: August 30, 2019, 05:26:42 AM »

Soooo, I didn't think of this upgrade possibility by my self but as soon as it was out there I was intrigued

I contaced Krontech as described in earlier posts and went through with the screenupgrade.

There were 3 basic options:
- I ship my camera to Krontech, they do an inspection of the whole camera and then upgrade the LCD, and then they send it back
- They ship me a complete working panel with the metal back case, a new encoder PCB, new speaker and new encoder knob.
- They ship me a LCD only (but removing your old LCD from the metal stands a reasonable chance of breaking it, even with a heatgun/controllable oven)

I'm not sure if I'm at liberty to post the actual prices here, but rather obviously they are ranked from most to least expensive on my end. I chose the second option.
The actual shipping went really fast considering the new screen had to travel over the Atlantic. As you might guess: shipping is a considerable factor in the total costs. Also as usual I had to pay import taxes, which were nowhere nearly as bad as for the whole camera back then. Moreover this time I had no hassle with customs but was a little surprised that the delivery guy wanted additional money from me as he stood on my door.

The upgrade went without any problems and most of the time needed I spent on clearing up my workbench to have some space

Here's a timelapse of the bench-cleanup and upgrade:
https://youtu.be/Wfa7LcX61D8

First impressions after a few minutes of usage:
- The new backpanel is way darker than the rest of the camera, but I don't mind that at all. Given time I trhink the colors will blend towards each other.
- There is a new style of encoder knob which is slightly bigger and now made out of metal with knurling on the sides and a dent in front for easy one-finger rotation. I havent played with it a lot but it looks and feels cool
- The screen looks sharper than the old one
- The new screen is brighter, but it wasn't as dramatic as i thought it would be. I'll need some time to properly compare the screens though.
- There is a slight offset on the left side of the panel before the lit part of the screen starts. I'm not sure if this was also the case on the old one, but now i noticed it for the first time.

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General high-speed discussion / Re: Shadowgraph Troubleshooting

« on: August 29, 2019, 10:40:15 AM »

Without having the actual raw file it's hard to diagnose, but my guess is on wrong bit-depth settings. The vertical stripes are in the MP4 version as well, but not as pronounced. Did you check the endian-ness of the raw file? Could also be a mapping issue from 12 to 8 bit or something related.

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Software Dev / Re: Chronos V0.3.2-RC1

« on: August 02, 2019, 02:35:30 AM »

I tried a few things and I'm not having any stuttering or freezing issues on the new firmware. HDMI out works, focus peaking is not a problem. I'm letting the camera warm up a bit more now to see if I'm affected as well but so far it doesn't appear so.
Edit: I decided to test the "Restore Default Settings" option and it just displayed the shutting down screen for 20 minutes without progress. I had to do a hard reset, but it seems to work fine again. Probably not related and a non-issue for me as I'm not intending to revert to factory settings often.

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General high-speed discussion / Re: Speed Calculations

« on: July 24, 2019, 09:03:48 AM »

Quote from: AIAS on July 23, 2019, 09:37:17 AM

For the calculation of the speed accurately. First, take two successive images from your video. you can use "free video to jpg converter" to extract every frame.

The Chronos can already safe individual frames, no need for external tools here. However a firmware upgrade might be required to do this.

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Software Dev / Re: Camera powers off after update to 0.3.2

« on: July 24, 2019, 09:02:03 AM »

Sounds to me like a low battery vicious-circle. Some daemon/script/whatever detects low bat ad triggers a shutdown sequence before the app is fully loaded. Might be related to the other battery issues reported for this beta version.
Did the reboots occur with the power cable plugged in?

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General high-speed discussion / Re: Control Chronos 1.4 via Laptop

« on: July 10, 2019, 07:53:09 AM »

There is no fully supported way yet, but some "hacks" to do certain tasks are already possible with the later software versions using the USB/Ethernet connection in conjunction with various autosave modes, just look around on the forums here for some sample scripts etc. Or just wait for the official new interface to be released hopefully soon^TM

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Software Dev / Re: Chronos V0.3.2 Beta - Updated June 25th 2019 with beta-6

« on: July 08, 2019, 10:50:05 AM »

Quote from: foobar on July 07, 2019, 07:13:34 PM

Do the vertical bands and the increased noise level issues persist after performing a black calibration? Note that changing the framerate will cause a change in frame timing that may invalidate the black calibration. In particular, framerates above 1053fps at 1280x1024 will need a different black calibration from framerates below 1053fps.

They mostly disappear after back calibration, and I'm now actually unable to reproduce the really noticeable ones I got on the first tests. Maybe doting several black calibs helped.

Quote from: foobar on July 07, 2019, 07:13:34 PM

As for the horizontal lines; There is a horizontal artifact that appears in the raw image that corresponds to timing of where the shutter signal changes relative to the frame readout. The line of the image where this occurs is normally corrected by the black calibration. However, if the shutter is changed after black calibration then the calibration data will no longer correct for this artifact. The result is that you will see one or two horizontal lines on the image that will persist until a new black calibration is performed. This issue has existed in all previous software releases of the Chronos.

Not really a problem though as I'm not intending to change the shutter during recording.

Quote from: foobar on July 07, 2019, 07:13:34 PM

Another possible cause of horizontal lines that we are aware of when changing the shutter from the main window. If the shutter is changed in the middle of a frame it can result in a change in brightness partway through the image and this appears as bright flashes while changing shutter. However the issue should not persist for longer than a single frame.

While testing I never got bright flashes but sometimes completely black horizontal bands in the recording, but again understandable and not really an issue for "reasonable" usage. If i ever need to change the shutter during recordings it might be also achieved by changing the aperture and so on.

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Software Dev / Re: Chronos V0.3.2 Beta - Updated June 25th 2019 with beta-6

« on: July 06, 2019, 02:16:22 AM »

Sorry for the delayed test, but here are my findings (just to be safe I let the cam warm up and did black calibration for all resolutions)

- in 0.3.2 b6 i now have vertical bands for the first time, never had them in any version up to 0.3.1 (images available on request).
- lowering the framerate while keeping the resolution the same dramatically increases the noise level. I'm not sure if this was always the case, but it seems new. I experienced this after doing a black cal on 1069 fps and with the lenscap still on then changing to 1000 fps.
- changing the shutterangle sometimes leads to horizontal bands on the display, haven't tried recording while changing the shutter yet.
- I really like the new util screen, especially for the storage!
- also had the full power fan on the first boot, now it seems to behave normally.

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General high-speed discussion / Re: Question regarding resolution and frame rate

« on: June 25, 2019, 07:54:03 AM »

As far as I'm aware this is not possible since the image sensor is read out in rows. Each row takes its time and substituting columns for rows while keeping the total pixel amount constant does not bring benefits, it instead slows down.
You can use the minimum horizontal size you need for the shot and then crop it afterwards to get square-ish images.

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