I think that you mean 0.7854 is a quarter Pi.
B.
You're bordering on the irrational.
I think that you mean 0.7854 is a quarter Pi.
B.
You're bordering on the irrational.
Lee.
Pi is an irrational number.
The fixed approximation 0.7854 is bordering on the irrational.
That is what was meant.
The few sandwiches short of a picnic is courtesy of Patrick Moore, as is a few slates short of a roof.
When I was in digs in the North East I could tell what day of the week it was by how many slices of pie there were on the plate.
All the best.
B.
Hi, Dennis. Twilight binoculars are mainly used by hunters and the best formats are classified by three main characteristics: magnification, exit pupil and tonnage (weight and size).So an 8x56 is the king of crepuscular binoculars or has the most nominal luminous power?
Your right. If the atmosphere is turbulent or you have a lot of light pollution the smaller aperture binocular or scope works better because you are looking through a smaller column of atmosphere. A lot of times I would use my smaller 80mm refractor when observing instead of my 10 inch Dobsonian because the atmosphere was so turbulent. Very few nights were steady enough to use my big 10 inch scope but when it was boy it was it awesome. It was just like you were orbiting the moon with a Nagler eyepiece in that big dobsonian.A 10X70 is good for astro with no light pollution under the night sky, otherwise any good 10X50 will show the same thing. The night sky has to be really clear with a 10X70, with no moonlight, and be able to fully utilize the EP.
Andy W.
As I have already explained, "my formula" is a deliberately simplified one to include only the nominal values of the binoculars format. Therefore, it makes no sense to include the transmission of light (although it is highly related to the topic - without a doubt)....only the combination of light transmission and size of exit puil determine image brightness...
Gijs van Ginkel
Why do you say this? I have already tried to explain the increase in visibility (not brightness) given by the greater magnification.You ask me to prove your statement, that is the wrong way to do it. It is upon you to prove your point and I will be very interested to see how you do it.
Best regards,
Gijs van Ginkel
You are simply revisiting the twilight factor.Here is your answer, Gijs
Why do you say this? I have already tried to explain the increase in visibility (not brightness) given by the greater magnification.
But anyone could see it.
Use a camera (even that of the phone) to shoot a burning candle from a dark room from 3m away, then do the same shot from 10cm away. The two shots will have different data about shutter speed or aperture or ISO sensitivity.
And the difference indicates that the more enlarged recovery of the candle flame (the closest one) has a greater amount of light.
Despite this, I do not intend to argue that the intensity of the light has changed, since the candle is always the same, but you do two tests before arbitrarily refuting.
If you try to do two calculations you will find that the formula has nothing to do with the "twilight factor". Indeed, this formula is specifically used to indicate the most suitable format at dusk (and not in the moonlight or at night).You are simply revisiting the twilight factor.
If you try to do two calculations you will find that the formula has nothing to do with the "twilight factor". Indeed, this formula is specifically used to indicate the most suitable format at dusk (and not in the moonlight or at night).
I advise you to do two tests seriously, before objecting in vain and without experience. If you have questions about calculations or how to seriously test, you can, I am available.
If you try to do two calculations you will find that the formula has nothing to do with the "twilight factor". Indeed, this formula is specifically used to indicate the most suitable format at dusk (and not in the moonlight or at night).
I advise you to do two tests seriously, before objecting in vain and without experience. If you have questions about calculations or how to seriously test, you can, I am available.
You have to do the tests at dusk, between about -2° and -9° of height of the Sun (after sunset or before sunrise, of a bright day) or with ambient brightness between about 20 and 2 Cd/m^2.What specific test(s) would you like to conduct?
Your perception of "bright" changes due to magnification. The light source, as you admit, doesn't change at all. A dim distant light bulb is perceived to be much "brighter" at 100X but it isn't.