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# Limiting Magnitude increasing with AGE. ?

Observing
5 replies to this topic

### #1 ziggeman

ziggeman

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Posted 22 January 2022 - 03:11 AM

Hi. I've seen several formulas that states that the older you get, the fainter the stars you can see!. How do they come up with this idea. Anyone?

https://www.cruxis.c...ngmagnitude.htm

### #2 Astrojensen

Astrojensen

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Posted 22 January 2022 - 03:38 AM

Errm -  they actually explain it clearly in the Cruxis calculator, including why it's not true in real life.

Clear skies!

Thomas, Denmark

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### #3 ziggeman

ziggeman

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Posted 22 January 2022 - 04:04 AM

Well, I was reading that also. So the formulae is not correct. Why keep it.

Edited by ziggeman, 22 January 2022 - 04:05 AM.

### #4 Stefano Delmonte

Stefano Delmonte

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Posted 22 January 2022 - 04:40 AM

Ooh that's will be great, in reality we don't need a formula to know is not true, just accumulate years and notice the change.

From the other side one parameter is corret and many times forgotten:  the experience.  Many times I've tried to show subtle details on planets to novice and they simply cannot see them.

An old italian saying: when you have teeth you have no bread and when you finally have bread you have lost your teeth

Ste

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### #5 ziggeman

ziggeman

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Posted 22 January 2022 - 06:30 AM

Ooh that's will be great, in reality we don't need a formula to know is not true, just accumulate years and notice the change.

From the other side one parameter is corret and many times forgotten:  the experience.  Many times I've tried to show subtle details on planets to novice and they simply cannot see them.

An old italian saying: when you have teeth you have no bread and when you finally have bread you have lost your teeth

Ste

It could be one of the several reason the italians love the other delicious wheat product , pasta so much

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### #6 TOMDEY

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Posted 22 January 2022 - 06:35 AM

Hi. I've seen several formulas that states that the older you get, the fainter the stars you can see!. How do they come up with this idea. Anyone?

https://www.cruxis.c...ngmagnitude.htm

There's a bit of legerdemain in that spread sheet thingy. The fallacy is in that age is transformed to the geriatric statistical diametric pupil-solve (so far, so good) but then only that pupil size is used in the computation, without regard for the inexorable/unavoidable/available geriatric eye degeneration statics. So it uses statistics re' one parametric, but ignores statistics for others. This selective practice is also rampant in many/most "Scientific Papers" --- especially when funding or political considerations supersede the stated intent of ~Science~ ... which is (theoretically) --- truth.    Tom

Oh! Thomas points out that they do indeed caution interpretation in the discussion. So that's good! Note also... the reason that smaller pupil favors discrimination is that the central region "of an otherwise healthy, youthful eye" is more efficient in getting photons to the retinal target cells.    Tom

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