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Topics - contpeeresto

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ATM, Optics and DIY Forum / Overcorrection vs Undercorrection?
« on: December 29, 2017, 12:08:05 PM »
I am continually trying to remember the patterns for overcorrection vs undercorrection. It's best to keep these memory joggers short and simple, otherwise they might not be remembered in the field when star testing.
The way I understand it, overcorrection will have an in-focus image with a fuzzier and larger outer ring, while the out-focus image will be more sharply defined. Undercorrection will have an out-focus image with a fuzzier and larger outer ring, while the in-focus image will be more sharply defined. So for me, it's easiest to recall the difference by keeping in mind "over-in-outer fuzzy" for overcorrection, and "under-out-outer fuzzy" for undercorrection.
Here is a page from which gives images and explanations of overcorrection and undercorrection.

Also, look at page 193, Fig 10.8, of Suiter's Star Testing.
So do I finally have overcorrection and undercorrection correct, or will I have to change that mnemonic before I commit it to long term memory?

ATM, Optics and DIY Forum / Protostar Defunct?
« on: December 27, 2017, 01:37:39 AM »
I purchased some FlockBoard to get a job 3 weeks back, got a confirmation email but never got a delivery confirmation.  I sent them two emails, 1 asking about the arrangement, another to cancel the order after a week and no reply from either.  I've tried calling during their business hours for the previous week also and no response.  They billed my credit card luckily but wondering if anybody knows anything?  Sounds odd to have no reply for weeks!

Eyepieces Questions & Recommendations / A question about barlows
« on: December 24, 2017, 03:00:08 PM »
What impact do these have the quality of your opinion?  How can they affect contrast, sharpness etc?Would a 10mm eyepiece be optically superior to some 20mm eyepiece of the identical household + 2x barlow, simply because it's fewer elements in the optical path?I'm considering buying some new eyepieces - especially for planetary observation, and which ones I get would rely on the benefit of a barlow.My goal is complete maximum contrast and sharpness.

General Astronomy & Observing / Where am I focusing my eyes?
« on: December 24, 2017, 10:00:56 AM »
Maybe not a difficult question... I know when I look up at the stars, I am basically focused on infinity, but what am I focusing when I look through the telescope?  Is it the focal length towards the mirror or something projected on the eyepiece?  Mysteries abound.

Light Pollution Topics / Approaching neighbors about their bright light
« on: December 24, 2017, 01:22:18 AM »
I have one neighbor nearby, a few houses down, that has a very intrusive glowing light that shines right in my own.  It's the only one that mars a relatively dark landscape (for a red zone anyhow).  I don't know them, never met them.  I am considering writing a letter to them explaining my plight.  I was not going to write my name or theirs, just use common terms as "neighbor".  Has anyone done this successfully?  What was your experience?  I looked up and it is a few elderly people, in their 70s.  I guess it does not hurt to try.

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