Chrony variation due to lighting changes.

[gohring3006]

I have a stand alone Chrony, and noticed on days of moving clouds. I will get substantial differences in velocity, when the sun is out, and when it goes behind a cloud. It will show a pretty big extreme spread. So yesterday I caught on to this and when I waited to shoot my strings when the lighting was the same. Very big difference!!!
Anybody noticed this? Am I late to this party?lightbulb

 

[J E Custom]

I have a stand alone Chrony, and noticed on days of moving clouds. I will get substantial differences in velocity, when the sun is out, and when it goes behind a cloud. It will show a pretty big extreme spread. So yesterday I caught on to this and when I waited to shoot my strings when the lighting was the same. Very big difference!!!
Anybody noticed this? Am I late to this party?lightbulb

It is not unusual to have problems with light changes on screens that do not have a deflector/defuser (Top on screen) that makes the screen more consistent in changing light. Normally, the better screens will work until they loose enough light that they just shut down.

Sometimes when at the range and testing very late, I have to break Out the magneto speed (It will work with no light) to finish testing.

J E CUSTOM

 

[snox801]

I have also had thi when I first got my .257 Roy back with a 28" tune it was giving me numbers of 3600 or better. When I posted it I looked like an *** because that's way higher than it should. I was running the sun shade and it was giving me normal readings before and after my .257. So I purchased a magneto speed and that solved the problem. I didn't know enough when I had it done to realize how fast that speed was I though I hit the jackpot to be fair so did everyone else that day at the range. 3600 was crazy fast for a 115 GR

 

[gohring3006]

It is not unusual to have problems with light changes on screens that do not have a deflector/defuser (Top on screen) that makes the screen more consistent in changing light. Normally, the better screens will work until they loose enough light that they just shut down.

Sometimes when at the range and testing very late, I have to break Out the magneto speed (It will work with no light) to finish testing.

J E CUSTOM

Good point Jerry, it was late afternoon when I was having the problems.

 

[gohring3006]

I have also had thi when I first got my .257 Roy back with a 28" tune it was giving me numbers of 3600 or better. When I posted it I looked like an *** because that's way higher than it should. I was running the sun shade and it was giving me normal readings before and after my .257. So I purchased a magneto speed and that solved the problem. I didn't know enough when I had it done to realize how fast that speed was I though I hit the jackpot to be fair so did everyone else that day at the range. 3600 was crazy fast for a 115 GR

Definitely looking at the Magnetto. Also looking at a lab radar.

 

[J E Custom]

Definitely looking at the Magnetto. Also looking at a lab radar.

Either one should solve that problem. I have not had that problem with the Ohler 35 p except near dark. But most of the time it just prints an error because the proof screen and the actual velocity does not agree, so I just disregard the shot and switch to a system that does not require light if I need to continue.

It is nice to have two chronographs to verify velocity that seems to high or two low. so I am very happy with the two that I have and can adapt to changing conditions.

J E CUSTOM