ULTRA-transparency

[A Scanner_darkly]

Hi all,
So to put my welcome post to bed;
What is ultra-transparency and how the heck with all the myriad transparency issues could you EVER get ULTRA levels of it ???

Its really simple actually, but first what IS Light Pollution ??
Then, how do you minimize it.

Mother Nature does that by rain, winds, and other complex weather systems interplay and how their various interactions act out for each unique location but essentially, when it rains and blows, it CLEANS all, scrubs the local area of all foreign particles, of all types, pollen, dust smoke and suspended water droplets WHY, and when static, a stagnant entrenched weather pattern, causes the ever increasing amount of that distressing possibly horrendous (and hideous) LP by the continuous added foreign particulates multiplying nefariously. Eg. Exhaust gases, industry.

BACK SCATTER is the CAUSE of why LP is.

Rain cleans it all up and the amount of derived transparency is  directly tied to the amount and extent of its duration.

If a system occurs which gives steady rains, heavy and extended periods of it, thats IDEAL potential conditions for ultra-transparency.

IF after several days of heavy rain know that is really just Mother shining up the windows, for a CRYSTAL CLEAR view out.

Let me tell you a true story of my only successful observation of B33, the HorseHead nebula and IC 434 the background part and NGC 2024 the Flame nebula with Alnitak centred in a TeleVue 70mm F/6.8 Pronto & T2 12mm Nagler.

This is 40X @1.75mm exit pupil and 2°true field.

I lived in Vancouver British Columbia for most my life so really blessed to have tremendoously good seeing AND plenty of rain; with at that time growing up(1980s) good darkness while discovering my love for astronomy (tiny Tasco & Huygens 20mm observing Pleiades nebulosity)  I'd guess B6-7 back then before Bortle, the steady decline in conditions till the present B9+ predicament but the good seeing remains however bad the LP is.

{ I imagine that with the same combo today I'd see EXACTLY the same view given the same conditions but I'm ahead of myself. }

In '94 I purchased my dream refractor and used it ever so briefly, this unit had excellent optics with next to zero SA, of course it showed some colour error but its smoothness of figure was beautiful, so I am impatiently waiting out a deluge of epic proportions, hey Van is known for wet but this was BAD, so 5 days later when it finally pooped itself out and was replaced with majestic seeing I decided what the heck and pointed it at Orions left belt [from close near the CENTER  (Burnaby)] and was STUNNED when in focus their were two (2) clouds ??!!

I was sure it was clear out so I  looked away from the Pronto to peer up and no it was clear so really  perplexed looked again into the Nagler and was floored, ASTONISHED actually, to see a little tiny dark hook precisely where B33 be.

The combination of my good eyesight, a good scope, PERFECT IMAGE SCALE plus a PURECLEAN atmosphere combined to shatter the notion of this being a difficult object WHATSOEVER.

I used 70millimeters remember.

I think its very hard to see because of three main things, too much applied power, poor atmosphere or poor optics or all three and include possible acuity issues and.....

The REAL secret lies in getting the initial view, the small scale contrast information condensed enough to make it more luminous THEN ADD POWER, increasing the image scale THEN, to get further enhancements to the observed target.

Its a very red object also, so if peoples acuity in the longer wavelengths is compromised REDUCE your power more.

It is PERFECTLY counter intuitive to ever try to observe a PERCEIVED  Extremely Difficult Object in the middle of a big city and I also would be blissfully unaware of how EASY it really is but for an impatience making me BREAK THE RULES, reading everyone problems you'd think you have to strain and use massive aperture when nothing could be further from the TRUTH.

Literally two clouds, can you imagine that??!!

REDUCE BACK SCATTER ENOUGH and its like being in outerspace

SO if any LONDONERS or other large population centre astronomers out there WITH good seeing thats also hit with lots of rain type climate, you have a narrow window of PERFECT  opportunity arrive when conditions of ultra-transparency materializes briefly, after heavy rains.

I was never able to accomplish the feat again as some lowlife stole it soon after.

Ultra-transparency;

When hard objects DO make themselves known.

No back scatter
No problems with LP
Simple as that !!

Clear steady and clean skies Y'all

Edited July 25, 2022 by Cornelius Varley
Text size