CED M2 Chrony light bar?

[DRNewcomb]

I tried to chronograph some loads this afternoon with my CED M2 but the shadow of the range awning coupled with the clear blue sky meant that the chrony not able to sense the bullets passing over the sensors. I'm considering getting some sort of LED bars to place above the sensors so that I don't have to wait for bright overcast to chronograph loads. Electricity is available at the firing line.

I was wondering if any members had solved this problem before and had any insights.

 

[rwj]

Yup ... get yourself a set of IR sky screens from CED (https://www.cedhk.com/ced-m2-chronograph-infrared-screen-set-). I’d also recommend that they be covered with black plastic when used outdoors.

 

[ronemus]

I've used the LED diffusers that CED sells - they work really well. I glued cardboard to the top side of the diffusers so that the only light was from the LEDs; the performance was very good and consistent, even with moly-coated .22 bullets at 3000 fps. They weren't that expensive and they directly replaced the standard diffusers. The screens use infrared light and determining which LEDs to make a home-brew solution would require some experimenting. Most commercial light bars emit visible light and wouldn't work with the CED sensors.

 

[rijndael]

If the solution for this is not cheap and easy, I'd consider a Magnetospeed Sporter.

 

[DRNewcomb]

If the solution for this is not cheap and easy, I'd consider a Magnetospeed Sporter.

Thanks but I'm looking for a $20 solution. I'd like to buy a Labradar but it's also not a $20 solution..

I was thinking of buying a couple LED bars from Amazon and rubber banding them to the diffusers. I didn't know if anyone had tried this or how well they'd work. For instance, do A/C LEDs strobe at 60 or 120 Hz like fluorescents do?

 

[JimSC]

use a battery operated LED light such as this one, 120 v AC powered LED's can flicker

https://www.lowes.com/pd/Blue-Hawk-11-93-in-Battery-Light-Bar/1000342419

you should be able to find a pair of the "puck" styles for less than $20

 

[ronemus]

Some light bars are powered by a DC power supply plugged into the wall; they would be fine. An LED bulb powered directly by 110 VAC, such as in a lamp, will flicker at 120 Hz ans won't work. Be sure to get infrared light bars so the CED sensors will respond.

 

[vonb]

I've used the infrared skyscreens with DC power. It works well in lower/later afternoon light. The issue with reading errors come into play on overcast days where the sun will peep through for a few minutes here and there. This will overpower the infrared light and cause errors.

 

[PhilC]

I tried to chronograph some loads this afternoon with my CED M2 but the shadow of the range awning coupled with the clear blue sky meant that the chrony not able to sense the bullets passing over the sensors. I'm considering getting some sort of LED bars to place above the sensors so that I don't have to wait for bright overcast to chronograph loads. Electricity is available at the firing line.

I was wondering if any members had solved this problem before and had any insights.

With or without the standard diffusers? I was getting some bogus readings when using the diffusers on cloudy days, so tried without and worked like a charm. Someday I'll have to try my IR screens...

 

[DRNewcomb]

I'm thinking about getting a couple of these, which are powered by USB phone chargers (5v DC). If it doesn't work out I can use them in the shop.

 

[DRNewcomb]

With or without the standard diffusers? I was getting some bogus readings when using the diffusers on cloudy days, so tried without and worked like a charm. Someday I'll have to try my IR screens...

I don't use the diffusers on cloudy days. The clouds are the diffuser.

 

[DRNewcomb]

I've used the infrared skyscreens with DC power. It works well in lower/later afternoon light. The issue with reading errors come into play on overcast days where the sun will peep through for a few minutes here and there. This will overpower the infrared light and cause errors.

My problem is that the range, which faces north, has a high awning over the firing positions which puts everything immediately in front of the line in a complete shadow. In the winter the shadow can reach out 40'. Before they erected the awning I could manage stray light by taping bits of black paper here and there to shade the light from directly hitting the sensors. Since the awnings, I can only chronograph rounds on cloudy days, sans diffusers. The club builds to satisfy what they view as what most members want but there are unintended consequences. An alternative is to move down to one of the "flexible" ranges (used mostly for "action" matches) but that would limit me to about 30 yds.

 

[ronemus]

I'm thinking about getting a couple of these, which are powered by USB phone chargers (5v DC). If it doesn't work out I can use them in the shop.

Those won't work - they put out visible light, not the infrared the screen sensors need.

 

[JimSC]

learned something

Those won't work - they put out visible light, not the infrared the screen sensors need.

Thanks for my learned something new for today.

If you are handy and frugal and can use a soldering iron, get a power supply and a couple of these and you can make your own. Just need to find out what wavelength you need

12VDC Waterproof IP65 SMD2835-36-IR Infrared (850nm/940nm) LED Linear Rigid Strip, 36LEDs 4W per piece

LEDLIGHTSWORLD infrared 850nm/940nm LED Linear Rigid Light Strip. This Waterproof IP65 LED Aluminum Shell Rigid Light Strip is sold 50cm long per piece. It's a 12VDC operation. Dimmable with compatible LED dimmers. Customized lengths accept. Technical Specification Wattage 4 Voltage 12V DC Beam...

ledlightsworld.com

Got curious and did a bit of digging, found an old thread on home made IR's for chronos, looks like you need a pair of the 850 nm strips. Just buy the 850 nm strips and get a 12v power pack and you will be in business

2 strips $32, rechargeable power supply $20 bucks.Midway sells the kit for 90 Bucks. Me I would splurge and just get the kit

https://www.airrifle.co.za/threads/16969-Infrared-Lights-For-Chronographs?p=265695#post265695

 

[rwj]

learned something

Thanks for my learned something new for today.

If you are handy and frugal and can use a soldering iron, get a power supply and a couple of these and you can make your own. Just need to find out what wavelength you need

12VDC Waterproof IP65 SMD2835-36-IR Infrared (850nm/940nm) LED Linear Rigid Strip, 36LEDs 4W per piece

LEDLIGHTSWORLD infrared 850nm/940nm LED Linear Rigid Light Strip. This Waterproof IP65 LED Aluminum Shell Rigid Light Strip is sold 50cm long per piece. It's a 12VDC operation. Dimmable with compatible LED dimmers. Customized lengths accept. Technical Specification Wattage 4 Voltage 12V DC Beam...

ledlightsworld.com

Got curious and did a bit of digging, found an old thread on home made IR's for chronos, looks like you need a pair of the 850 nm strips. Just buy the 850 nm strips and get a 12v power pack and you will be in business

2 strips $32, rechargeable power supply $20 bucks.Midway sells the kit for 90 Bucks. Me I would splurge and just get the kit

https://www.airrifle.co.za/threads/16969-Infrared-Lights-For-Chronographs?p=265695#post265695

The kit from CED lists for $90 and integrates directly with the sensor heads...