Messages

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Chronos User Discussion / Re: Settings to capture air gun bullet hitting the target

« on: May 05, 2023, 07:44:08 AM »

Right, vertical positioning of the camera could make sense in this case. I just wonder if the bar is not too narrow. What would be the approximate optimal distance between the camera and the sample here? And the distance between the light and the sample? Should I place the light right behind the camera (once it's perpendicular to the table) or more to the side?

Yeah, I tried editing the post but I couldn't remove the old attachment and both versions were added to the post. Maybe because I was using another computer.

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Chronos User Discussion / Re: Settings to capture air gun bullet hitting the target

« on: May 05, 2023, 07:34:32 AM »

Wow, I didn't know that so much light is needed for such recordings. I guess that I will have to place the lamp very close to the sample.

I attached a simple sketch of the view from above of my current test setup with which I got poor recordings (the sample was not used yet, shots went directly to the styrofoam block). It can be modified if needed (especially when it comes to light and camera placement). I'm not sure about the distances but the lamp was around 1.5 - 2 m away from the sample and the camera was < 1 m away from it. In the actual test, the camera should be placed perpendicular to the table (and thus also bullet trajectory). There's also an acrylic glass cover placed around the sample and the camera will be looking through it. Hopefully, it won't cause any issues with recording quality. The dimensions of the sample are around 90x90x23 mm. It will be attached to a wooden plate with aluminum profiles offsetting the sample from the plate (to see what happens after penetration). The plate will have a hole through which the bullet can pass.

The biggest issue is how to capture the proper region with the camera. It needs to include the sample (vertical rectangle of 90x23 mm size) and some area before and after it. With those narrow boxes captured at the highest frame rates, I would probably have to place the camera far away to capture everything. If I get too close, the camera with the current lens may not see or focus on the whole area of interest. Unless I'm missing something.

Edit: I removed the old post to replace the incorrect scheme - I forgot about the aluminum profiles offsetting the sample from the plate.

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Chronos User Discussion / Re: Settings to capture air gun bullet hitting the target

« on: May 05, 2023, 06:11:29 AM »

Thank you for the advice. I've figured out the name of that lamp. It's F&V Z1200VC CTD-Soft. Should it be sufficient ?

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Chronos User Discussion / Re: Settings to capture air gun bullet hitting the target

« on: May 04, 2023, 01:21:41 PM »

Thank you for all the tips, black background might make more sense in my case then. What about the lens settings (like aperture)? Should I change them from the current ones somehow? Apart from adjusting the focus, of course. Also, are there any important settings of the camera itself (recording/saving) that I should adjust in such conditions? Perhaps this camera is not sufficient to capture a projectile at so high velocity but it’s the only one I have at my disposal.

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Chronos User Discussion / Re: Settings to capture air gun bullet hitting the target

« on: May 04, 2023, 12:51:29 PM »

It seems to be much more powerful than the linked one, only the style/shape is similar. I will try to figure out the exact model of that lamp.

By the way, it might be a stupid question but I'm really inexperienced in such tests - my projectile can be silver or coppery and the target is light orange. Should I use white or black background? Which one will be better for filming? I would choose the white one but I've heard an opinion that black might be better.

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Chronos User Discussion / Re: Settings to capture air gun bullet hitting the target

« on: May 04, 2023, 12:16:47 PM »

I attached a picture showing the current settings of the lens.

The light is in the form of a large wide rectangular lamp (likely LED) on a tripod. Like this (horizontal version): https://m.media-amazon.com/images/I/71Cg-A0vSGL._AC_UF894,1000_QL80_.jpg It provides bright white light which should be enough to illuminate the scene. The normal room light was also on when I was recording. I've also tried using a lamp similar to this one: https://www.toolstation.com/luceco-110v-single-head-tripod-work-light/p88271 but it wasn't powerful enough.

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Chronos User Discussion / Re: Settings to capture air gun bullet hitting the target

« on: May 04, 2023, 11:51:29 AM »

Hi, Can you provide any Further Detail on the Light Source you are using, also on what Lens you are using (Especially Lens Settings)?
 .
 Regards Resolution, there is not much to be done about that, if you want / need more Frames Per Second to capture Faster Events, you Resolution gets lower, that is just how Highspeed-Cameras generally work.

Thank you for the reply. Unfortunately, I won't have access to the light source until the actual experiment since it's in the lab. I can provide the data regarding the lens though. It's Nikon AF Nikkor 85mm f/1.8D with HN-23 hood. I only adjust its focus on the target.

So, when it comes to the resolution, those highest frame rates will always be just very narrow bars? There's no way to stretch them somehow? I don't need very good image quality, I just want to capture the whole target in such a way that all the objects (including the structure of the target, debris and bullet) are distinguishable and the recording can be used for research purposes.

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Chronos User Discussion / Settings to capture air gun bullet hitting the target

« on: May 04, 2023, 11:21:51 AM »

Hi,

I'm very new to high-speed camera usage. I need to record a spherical projectile coming from an air gun (BB gun to be precise) at around 92 m/s and hitting a 3D-printed model about 1.4 m away. The camera I have at my disposal is Chronos 2.1 HD. I've already made some tests but there are 2 problems:
1. The recording is too dark, even with the shutter slider set to max. There should be enough light on the scene since I'm using a large professional lamp. Are there any settings that I should check?
2. With 1000 fps (1920x1080 resolution) the bullet is not even visible in the recording, I can only see the debris after impact. Thus, I tried with 14 825 fps (1280x96) but then the image changed to a narrow bar and only this region was recorded. How can I fix it? Also, with this frame rate, the bullet is visible when traveling through the air but it's still very fast and hard to notice. Is it even possible to capture such a velocity using this camera? What settings would you recommend for my case?