Hello is anyone using this camera for golf swing analysis?
Are you able to get crisp images and if so what were/ are your light requirements?
Last question.. able to set up in Kinovea fairly straight forward?
1 (edited by jeromekj 2024-02-10 22:00:46)
Hello is anyone using this camera for golf swing analysis?
see a recent post from today regarding the cameras. I have a similar from Basler and it does a good job. The price/performance relation is very good. A big advantage of the sensor size of 1/2.9" is that you may use relatively cheap lenses for it. Most C-mount lenses cost about 100 Euro, using S-mount lenses (lower quality) will cost about 50 Euro. If S-mount lenses are used, you have to check if the focus of the lens will fit to the camera.
Light requirement depends on your local situation of how much day light you have during recording. If not, you need a light that has a low flicker rate. Going down below 1000 microsecond shutter speed, it has to be absolutely flicker free. Carefully check the specification of the light.
I have had a color camera, but the mono needs significantly less light.
It works fluently with Kinovea
Reiner is Basler a better camera?
I do currently have a 3 mega pixel 1/2" 2.8-12mm 1:1.6 lens.
My application is for golf and yes to the flicker free bulbs, I have close to 30,000 lu (just under) flicker free.
Would you recommend the mono over color? Any more and I'll washout my projector.
I tried Swing Catalyst but prefer to use Kinovea and would like to get in the 800 microsecond range or lower.
Thank you for what you have posted on the other threads that I have read and any info you have on the camera.
Some one posted about Get-Camera and Daheng Mer2 has the best price i have seen for a IMX 273 chip at 227fps,
Basler's comparable is the Ace acA1440-220um which is like $125 more than the Daheng. Is Basler that much better?
The lens should be OK, Aperture of 1.6 is a good value. 1/2“ will fit to the 1/2.9“ sensor to prevent vignetting.
I assume it is a C-mount type. If you will buy a further lens, try to go down to a fixed focus lens with an aperture of 1.2 , it increases the brightness of the image a lot and gives you a more crisp image. On the Basler webpage there is a good lens calculator to estimate of what lens you need. Set your distance of the camera to your room dimension and the width of the FOV to about 4,5m to calculate.
30000 lumen is a lot. I have 2x20000 but installed a 1-10V dimmer to better adjust it to the local light situation.
I highly recommend a mono camera due to factors:
In USB-cameras the limit of bandwidth is in the range of 300-400 MB/s data transfer.
Assuming an image of 1000x800 pixels, fps 100, AVI/MKV uncompressed format, in color mode the transfer is about 240 MB/s (1000x800x100x3)
Going up to 1240x1024 pixels, fps 100, the raw data transfer already is 571 MB/s and therefore over the limit.
Same resolution using mono, it is about 190 MB/s (1240x1024x100x1).
You could say, OK, I will use the compressed format MP4. However, then the computer system/Kinovea will have to do the compression and you will see a lot of dropped frames.
To overcome that situation I checked the Baumer camera. They have MJPEG compression build in. But they cost 2500 Euro each.
The second reason I like to use the mono camera is the light intensity that is much better in mono-cameras compared to a color camera, needing less surrounding light.
Anyway, in indoor video analysis you need a lot of light. I actually have switched from an Optoma 1090 HD-projector (3000 lumen) to the Optoma 4K400STx (4000 lumen) and the improvement is impressive. I think it is not only the 4k but more the much brighter image. The screen washout now is minimal also in the situation of sufficient LED light.
I do not think that there is a real difference between the Daheng and Basler camera of the same IMX274 chip. The support of Daheng was fine and needing 2 camers the difference already is 250. The only advantage of the Basler to me was the driver. You can connect and disconnect the camera at any time and it works. However, this advantage only was evident during testing a lot outside Kinovea. If you have Kinovea running, the plug and play doesn’t work anyway and is not needed.
Wow a lot to digest! Thank you!
I will chk out that lens if it uses less light.
I have my lights on 2 separate switches, if i want the whole swing all of the lights and if i set it for a smaller shot (club head contact only) then i am hoping for just the one bank of lites. I am using an Optoma ZH403 1080p, wish I had the 4 K but it is a 4000 lumen laser projector and it’s pretty good. This has become a bit of a rabbit hole , throwing money at my game but i think i see daylight. Thanks for your help, I’ll go with both suggestions.. mono and lens.
I’ll check back with you after i get them!
Reiner I am on the Bassler web site, for comparable Basler vs Daheng would be the acA1440-220um both use the C-mount with the same IMX273 sensor. I don’t have a clue as to the 38 suggestions for the lens. You mentioned ‘fixed focus’ and I’m not sure how to put that into their equation. My room is a 2 stall garage so height is 9ft or 3 M and width you mentioned 4 to 5 M which should be good. What I am unsure of is distance away from me and the camera is about 80 inches so 2 Meters. I did not see a spot to put in the aperture of 1.2 that you suggested. Suggestion on how to navigate or was I not on the correct page.
7 (edited by Reiner 2024-02-19 20:39:49)
This is the webpage of the lens calculator
You have two options. First, enter the camera on the left side. Second, enter the sensor chip and the adapter type on the right side.
If the working distance is small, it might be better to start using the right side. C-mount lenses go down to a focal length of about 3,5 - 4mm.
However, that might not fit your need if the camera is close to the object.
Therefore, start with the sensor chip IMX273 and S-mount adapter.
To get a full FOV (field of view) of a golfswing, a width of 4500mm and height of 2800mm at the golfers body position is needed.
Start the calculation with a width of 4500mm and a working distance of 2000mm in your case (or 2600mm if your measurement was from camera to ball).
The calculation displays a focal length of 2.2mm. The calculated height of the FOV is about 3370mm.
2.2mm is near a fish-eye lens and has a lot of distorsions, that is not recommended.
Do a further calculation, resetting the values, entering a height of 2800mm. In most cases this will be sufficient. Enter your working width of 2000mm.
You will get a focal length of 2.7mm.
I’ve personally used a S-mount lens with a focal length of 2.9mm that works pretty good (the distance camera to object was a little bit higher).
You may check the FOV again resetting the webpage and enter the 2.9mm focal length to see the FOV you can achieve.
You do not necessarily have to buy the S-mount lens from Basler. There are different other companies available that produce good quality S-mount lenses. I bought my from Lensation. However, be aware that the lens will fit to your camera (Focussing and Sensor size). In general, the support of the company should tell you if the lens will fit.
The so called aperture is a value inherent to the lens and does not change the geometry. In general, the lower the aperture is, the higher the price.
In general, the Aperture values of the S-mount lenses are higher than in C-mount lenses. Therefore you need more light.