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Chronos User Discussion / Re: 11 second chronos 2.1 clip
« on: February 09, 2020, 09:33:47 PM »
yes, that makes sense that the flicker is from the room lights.

btw, the 2.1 will not let me set the resolution lower than 640 x 480 and fps any faster than 5,406.  it rejects anything beyond these limits and won't let it be applied to the setting.

the data sheet indicates that it should be able to do 1920 x 8 at 100,000 fps, but this appears as though it's not possible with the current version of the software.

https://www.krontech.ca/wp-content/uploads/2019/04/FM-ENGR-50002-Chronos-2.1-HD-Datasheet-Rv1.pdf

also, looking at the data sheet, there's no way the battery runtime is an hour long.  i can sit and watch the battery drain 1% every 10-15 seconds.  seems like it might last 15 minutes tops.

hopefully software updates allow greater than 5,000 fps because the reason i bought it was to do some engineering analysis that will require at least 10,000 fps.  low resolution isn't a problem for the analysis, but i need the speed.

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Chronos User Discussion / Re: 11 second chronos 2.1 clip
« on: February 09, 2020, 12:47:12 PM »

i used two LED lights (amazon.com/gp/product/B07Y85Z7ML) when i shot the video.

i assume the flickering is because of some kind of refresh rate on the LED lighting.  i'm not sure.

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Chronos User Discussion / Re: 11 second chronos 2.1 clip
« on: February 08, 2020, 09:54:34 PM »

here's a new clip 1k fps at 1920x1080: https://youtu.be/T0FSl5ORMEM

and here's one at 5k fps at 640x480: https://youtu.be/8xpxutVUQTg

i don't think the 2.1 can do any faster than 5k.  i believe the 1.4 can do 20k at a low resolution.  it's kind of a bummer that the 2.1 can't do that.  i'm assuming that's a software limitation.

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Chronos User Discussion / Re: 11 second chronos 2.1 clip
« on: February 08, 2020, 09:27:57 PM »
oops - yes, i just noticed that i have it set to 2.8, not 1.8

the lens is a Nikon AF Nikkor 50mm 1:1.8 D

it was shot with 0db  gain.

i'm not sure what you mean by shutter angle, but it the 1000 fps setting sets the exposure to 993.23 usec.

i'll try taking another recording and posting it.

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Chronos User Discussion / 11 second chronos 2.1 clip
« on: February 08, 2020, 11:58:26 AM »
i got some lighting and an okay lens.

here's a 1920x1080 1000FPS clip:  https://www.youtube.com/watch?v=P5TU0oZnp0Y

it's at focal ratio of 1.8 and the focus might be a little off.

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Chronos User Discussion / Re: what do you think about this lens?
« on: February 06, 2020, 03:50:50 PM »
thanks!  great info.   :)

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Chronos User Discussion / what do you think about this lens?
« on: February 05, 2020, 09:15:06 PM »
i'm lens shopping for the 2.1 and it looks like this might be a good match:
https://www.bhphotovideo.com/c/product/967345-REG/sigma_18_35mm_f1_8_dc_hsm.html/overview

it's zoom, but it has a very fast ratio (1.8) which should let in a ton of light required for high frame rates.

opinions?

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Chronos User Discussion / Re: new clueless 2.1 user
« on: February 05, 2020, 12:54:56 PM »
that really helped a lot.  thanks for posting the video.  as soon as i rigged the aperture to stay open, the darkness issue went away.  now i can record indoors in regular light (it still is crappy, and you really need bright lights) but at least i can see things on the display!

the weird stripe issue went away, but it seems like there are just some bugs when using lower FPS numbers that need to get worked out.

i recorded some water dripping from a faucet and it looked pretty bad - it was too dark, and it was kind of blurry and grainy.  obviously i need more light, and i should also do a black calibration and also figure out how to focus.  it's too early to tell how the quality of the camera is until i get those basic things sorted out.

anyway, thanks again for your help!

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Chronos User Discussion / Re: new clueless 2.1 user
« on: February 05, 2020, 07:03:27 AM »
>Also still wondering, what kind of lens you use right now to test this?

"AF-S NIKKOR 18-70mm 1:3.5-4.5G ED"

>Is this actually an 2.1 Chronos or an 1.4 One? Or is there any other Reason for this resolution?

it's a 2.1.  i just set it at the lower resolution to try things out and to see if i could actually see anything besides darkness on the display.  i figured setting it at 30 fps would be more like a regular video camera and i should be able to see something.  i tried lots of different resolution and different frame rates.  seems very buggy.

thanks for the lens recommendations.

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Chronos User Discussion / Re: new clueless 2.1 user
« on: February 04, 2020, 09:57:20 PM »
thanks for the response.  i appreciate it.

so, i wasn't asking for the best lens, just any specific lens that would be a good match for the 2.1 - i understand that there's no such thing as 'best' for all applications.  i'm new, so i just wanted a specific recommendation for a generally useful lens that would be a reasonable match up for the 2.1

the current lens i'm using was just something i grabbed off an old nikon camera that i had in an old box.  the label says "AF-S NIKKOR 18-70mm 1:3.5-4.5G ED" so it's some kind of a zoom lens of sorts.  just looking at it, it clearly blocks the outside edges of the CCD, and so does the adapter that came with the 2.1 so it's certainly sub-optimal.

so i found a user manual for the 1.4 here: http://www.krontech.ca/wp-content/uploads/2019/03/Chronos-1.4-Beta-0.3.0-User-Manual-r1.pdf which was really helpful.  the 2.1 didn't come with a manual, but it came with a piece of paper with URL on it that linked to a page with 3 youtube videos, 2 of which didn't work (some kind of playback error) so i was totally clueless about how to do anything.

i managed to set the FPS to 30, and in a room with moderate light at least i could see the room (albeit dimly) in the display.  when setting to 3 FPS and running a black calibration the screen seemed to just show a pink blotchy display, and wouldn't respond to a light (i shined a flashlight in the lens and nothing changed) so i rebooted it, and now it's stuck on a vertical striped display.  seems like it doesn't like low FPS.

i then changed it to 10 FPS and tried a black calibration and the display went black and won't respond to the flashlight at all.

i went to the util screen and reset the settings using "Remove User Calibration Data (Revert to Factory)", but that didn't seem to do anything.  all the settings appear to be the same, and the camera display is still blank.

so i switched to 24 FPS and recalibrated.  now it shows the flashlight, but it's all striped.  seems like a bad black calibration.  i tried again.  same thing.  it's kind of hard to tell when the calibration is done.  the words appear on the screen saying it's doing a calibration, then they go away after a few seconds, but i'm pretty sure it's still calibrating.  other times the words just flash for a fraction of a second.

now there are 2 big black splotches on the display that won't go away.  i think the CCD got saturated by the flashlight, and it's temporarily burned those pixels.  i hope a reboot fixes this.  black calibration didn't.

okay, rebooted it, now it's stuck like this:

<Image temporarily removed due to forum bug causing topic to come up blank>
Image attached

sigh.

well, i guess this is how it goes when you get an early-bird version.  i'm not complaining, but i've got a lot to figure out here.

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Chronos User Discussion / new clueless 2.1 user
« on: February 04, 2020, 01:34:55 PM »
hi all.  i just received a 2.1 and since there is no documentation on this yet, i figured the forum might be a good place to ask some questions:

1) anyone have a link to a specific lens that would work with this?  links?  (i read the lens thread that has been posted, and i didn't find it to be new-user-friendly enough for me - i just got that i've got a 4 / 3" chip and so i need a lens with an image circle that doesn't cause vignetting.)

2) holy cow everything is dark.  like pitch black unless i point to a lit light bulb and then i see a very dim light bulb in a sea of blackness.  i went outside (it's very sunny today) and cranked up the gain to 24, and it's still pretty dark.  i suppose this is normal?  for indoor use, any recommendations on particular kinds of lights?

3) i suppose i need some kind of trigger to make this work.  any specific recommendation on a trigger?


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