Pro chronos I know direct sunlight is not the best unless you use like the sheet trick. But what about bright sunlight and snowy ground good or bad condition?

I've had pretty good luck with them in those conditions.

No problems with mine. In bright direct sunlight, I use a cheap furnace filter as a light diffuser.

Good shootin' -Al

That's a great suggestion. I sometimes use a piece of cardboard attached with clothes pins to the factory diffusers.

Another great thing about using a furnace filter.....the wind won't launch your chronograph off into the next zip code. I use a couple of metal binder clips to hold it in place on the metal rods....one above and one below. The Pro Chrono goes into a padded bag that holds the telescoping stand and extra batteries. The furnace filter just gets folded over and stuck inside the bag.

Good shootin' -Al

In Seattle at 600 feet. the problem is pupil size with dark cloudy skies, and I have to turn down the power on the scope.

But in Montana at 2600 feet, the sky is black when looking straight up. THere is no background for the chrono to see the bullet.

But if I tip the chrono sideways, so the background is a white storage box, the the chrono triggers every time.

Of course, when there are clouds at 2600 feet, the box is not needed.

I made it through this post without mentioning Einstein and Oxygen scatting blue light. [why you can look at a sunset]

I have always just used the screens that come with the chrono. Is there a reason not to use them?

90% of the time, the supplied screens work fine for me. In certain situations (sun angle), the improvised filter does the job.

In direct sunlight, coating the bullet with a black Sharpie also helps.

Good shootin' -Al