Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - Rainer

Pages: [1] 2
1
Chronos User Discussion / Re: Low light capture
« on: November 05, 2021, 12:40:35 PM »
I really like the viewing angle. The whole Life Saver lights up where it's being hit. Really nice shot.

2
Chronos User Discussion / Re: Low light capture
« on: November 05, 2021, 07:14:30 AM »
There doesn't seem to be a gain setting in this camera. At least I did not find one in the manual or software. I always records in RAW and with a histogram-like window I can convert these RAW images into JPG or other formats. For the low light shots I tried to squeeze the brigt light out of these RAW images as much as possible.
I am very interested if anybody else is recreating the Life Saver shots!

3
Chronos User Discussion / Re: Low light capture
« on: November 03, 2021, 06:56:21 AM »
my lens/settings were the following:
PCO.dimax HD with Zeiss 1.4/50mm lens (Nikon DSLR Mount)
5000 fps
720x684 pixel
0.179100 ms exposure time

4
Chronos User Discussion / Re: Low light capture
« on: November 03, 2021, 02:39:58 AM »
I also recreated the Life Saver video with my high speed camera - not a Chronos but a PCO dimax HD.
It's important to use the Wint-O-Green version since the included oil shifts the light into the visible wavelength. I totally missed this at first and hammered lots of normal ones.
I recorded with 5000 fps in RAW and then tried to squeeze everything out of the images when converting them to a video.
I come nowhere close to the quality of the Phantom shots, but I see the sparking quite well which made me happy.

YouTube is doing terrible compression thing to noisy videos, so if you want the original files, PM me.
https://www.youtube.com/watch?v=vzPAz24czHM
https://www.youtube.com/watch?v=iWxgRPquz3w


5
Chronos User Discussion / Re: Pre Record Trigger Delay <1 frame?
« on: October 15, 2021, 02:05:01 AM »
Hi,
I had the same challenge with two other high speed cameras and solved it via an external trigger.
Both camera where in triggered mode, taking a picture whenever an external trigger is received. I triggered them first with an arbitrary function generator. This worked well - I could trigger the camera "interleaved". When it became too complicated to program the function generator with different frame rates, I used an Arduino setting two pins alternating high and low. This also worked very well.
Meybe external triggering is also an option for you.

6
Thanks for this real-world experience and feedback, Nikon1

7
Oh, I did not know that. Is it improving the saving speed?

8
Hello all,
I don't have a Chronos (yet) but another HighSpeed Cam from PCO. The limiting factor when shooting multiple scenes is the time it takes to save the buffer via USB to disk.
On the forum I read a lot about Chronos saving speeds with different file formats and storage media and I feel that this would affect me heavily when I get a Chronos.

Would the following suggestion increase the saving speed (mainly a questions for the Krontech devs):
Instead of converting the RAW image data from the RAM into h264, DNG, ... do the following: dump the data from the RAM exactly as it is in the RAM (no conversion to any file format).
One would end up with a huge binary dump on the storage medium.
Later - on the computer - one could convert this binary dump into h264, DNG, ...
I have the feeling that the conversion from RAW to an image format is a time consuming step for the FPGA in the Chronos. If this step is "outsourced" to a computer, would it make continuous shooting faster?
It's just an idea, but I would use it right away with every high speed cam I ever used.
Thanks for reading my suggestion, I am really interested if this would be feasible.
Rainer

9
For my tests with cameras and external triggers I tried a function generator and an Arduino.
tl;dr: it was easier with the Arduino

I have a two channel function generator (Rigol DG1032Z to be precise). I configured it in a way, that on channel 1 I get a 5V trigger with my desired framerate, e.g. 1000 Hz.
Then I configured channel 2 in the same way. Then I set channel 2 in a way, that the triggers from channel 2 are exactly inbetween the triggers from channel one.
(Google "phase difference" for more info) Some function generators specify this in degrees, so a 180 degree phase difference means that channel 1 is shifted half the frequency.
This did work. Out of my two channels came alternating triggers.
And now the "BUT":
When I wanted to change the frame rate, I had to configure the second channel again and completely new. I tried all settings (locking the channels to each other,...) and read the manual, but changing the frequency (which means framerate) always made the settings from the 2nd channel messed up. I configured the generator with the buttons on the device. You can also do this via an USB connection, but then I used an Arduino.

And there - within 5 minutes I had 2 pins alternating the triggers with ease. It is basically just some delays and pulling the pins up and down.
I did this "manually" by changing the delay times in the source code and it worked good enough for my basic tests. I wanted to test the beam splitter after all.
One could modify the Arduino sketch maybe even with a display to create a changeable frequency with a rotary enoder as an input. But this was too much effort since I had a running solution for my tests.

I hope I explained everything in an understandable way.
Tell us when you ever try it, lwaters, I'm interested in your solution.

10
Hi,
I once tried this with two other cameras which have an external trigger. I got a cheap beam splitter from Aliexpress which is a small piece of glas which reflects 50% of the light and lets 50% of the light pass through it. When you arrange the two cameras 90 to each other, one looking "through" the beam splitter and one looking on the reflective side, they both see the thing you want to image. (It's best to google some images for this, it's hard to describe with words)
Then I triggered the cameras alternatly and combined the two "picture stream" in an interleaved way afterwards to a movie.
In principle this worked, but it became evident, that you need more light and that the alignment of the cameras and the beam splitter is crucial. If they are slightly off, the image jumps frame by frame. If the offset is only small, one can try and correct this in the final images and "shift" one image stream in a way that the overlap better.
So it is possible (with Chronos or other triggered cameras) but it takes quite a lot of preparation.
Best regards
Rainer

11
I am really impressed by this project and very curious how the image noise will be affected. Great work!

12
Chronos User Discussion / Re: New Chronos 3.7 4k !
« on: October 20, 2020, 12:05:23 PM »
Is this an actual working thing?  :o

13
Chronos User Discussion / Re: Post Chronos 2.1 clips here!
« on: August 28, 2020, 12:26:23 PM »
https://vimeo.com/452567484

Amazing shots for the first day! I also like the music (could you tell where it is from?). It fits the shots very nicely. Well done!

14
Chronos User Discussion / Re: Is Krontech still in business?
« on: August 05, 2020, 12:17:08 AM »
Since I am thinking heavily of getting a 2.1, I emailed Krontech on July 22nd asking how long the current delivery time is. They responded just a day later and told me, that if I order a camera now (=July 22nd), I might get it around mid-end of August. I have not ordered yet (will wait until the summer holidays are over).
Maybe an official Krontech reply in this thread would be possible?

15
Chronos User Discussion / Re: Footage right out of the camera
« on: December 19, 2017, 06:32:53 AM »
Thanks to both of you, this is exactly what I was looking for.

Pages: [1] 2