What is the exact area of unconformality of bipolar oblique conic conformal?

General discussion of map projections.
Piotr
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Re: What is the exact area of unconformality of bipolar oblique conic conformal?

Post by Piotr »

daan wrote: Sun Apr 19, 2020 2:23 pm Or just use the same process you already used but with much smaller maximum angular distortion setting for distortion visualization in order to arrive at something more obvious that you might understand? Do you need something more precise than this?

BOC1.jpg
— daan
So why then is bipolar oblique conic conformal marked as a Conformal projection, when it fails conformality in infinitely many points?
daan
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Re: What is the exact area of unconformality of bipolar oblique conic conformal?

Post by daan »

Piotr wrote: Sun Apr 19, 2020 10:24 pm So why then is bipolar oblique conic conformal marked as a Conformal projection, when it fails conformality in infinitely many points?
Because it’s perfectly conformal over nearly the entire region that it intends to map. Most maps that are “almost conformal” have no conformal regions. Bipolar oblique conic conformal is an unusual case. Calling it non-conformal seems less useful than calling it conformal.

— daan
Piotr
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Re: What is the exact area of unconformality of bipolar oblique conic conformal?

Post by Piotr »

daan wrote: Sun Apr 19, 2020 10:29 pm
Piotr wrote: Sun Apr 19, 2020 10:24 pm So why then is bipolar oblique conic conformal marked as a Conformal projection, when it fails conformality in infinitely many points?
Because it’s perfectly conformal over nearly the entire region that it intends to map. Most maps that are “almost conformal” have no conformal regions. Bipolar oblique conic conformal is an unusual case. Calling it non-conformal seems less useful than calling it conformal.

— daan
But doesn't it introduce misinformation in Distortion Visualization by not showing unconformal regions?

What is the exact boundary of bijectivity in bipolar oblique conic conformal?
daan
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Re: What is the exact area of unconformality of bipolar oblique conic conformal?

Post by daan »

Piotr wrote: Sun Apr 19, 2020 10:47 pm But doesn't it introduce misinformation in Distortion Visualization by not showing unconformal regions?
Yes.
What is the exact boundary of bijectivity in bipolar oblique conic conformal?
I don’t know. The “stitching” function Miller created to fill in between the two conics starts misbehaving not far outside of the region Geocart uses as a boundary. I have never had occasion to investigate the effects.

— daan
Piotr
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Re: What is the exact area of unconformality of bipolar oblique conic conformal?

Post by Piotr »

daan wrote: Sun Apr 19, 2020 11:08 pm
Piotr wrote: Sun Apr 19, 2020 10:47 pm But doesn't it introduce misinformation in Distortion Visualization by not showing unconformal regions?
Yes.
Why do you put misinformation in Geocart?
daan
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Re: What is the exact area of unconformality of bipolar oblique conic conformal?

Post by daan »

Piotr wrote: Mon Apr 20, 2020 1:20 am Why do you put misinformation in Geocart?
Because bipolar oblique conic conformal, as a unique case, is not valuable enough to drive Geocart’s behavior for all other projections, in my opinion. In the unique circumstance of someone (you) caring about the behavior in the non-conformal region of BOCC, you are able to get the information you want by other means within Geocart anyway.

— daan
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