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Power & Aperture?

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WWJ's picture
Joined: 2010-08-06


Suggest visual observers might cite power and aperture employed with estimate, in the comments column. This could be helpful to other observers sourcing “Quick Look “. Only between 4 and 7 keys necessary; example: 8x42 or 80 x203. No technical description is otherwise needed. Deep sky and planetary observers append these details. Surely, equally significant with variable star estimates. Comments welcome.

Maybe add a field in WebObs?
lmk's picture
Joined: 2010-07-23

I am generally of the opinion that more information can never hurt. However, after extensive testing on my own, I have not found much significant difference in estimates between large/small aperture and high/low power, provided there's no substantial color difference issues with the variable and comp stars.

If the colors start to show up with the large aperutre, of course then differences in B-V begin to have an effect on the estimates. So, I think the aperture (primarily) and power would be helpful to differentiate such cases, if the question ever comes up. Another important visual piece of information is whether the estimate is made infocus or defocussed.

Putting them in a required field in the form rather than in the optional comments section makes more sense to me. Most observers would probably omit that sort of info in the comments, especially if they are unfamiliar with this thread.

Mike LMK

But keep in mind that most of
WI's picture
Joined: 2010-09-01

But keep in mind that most of the world uses the metric system. Does that "8" signify 8 inches or 8 centimeters? There should be a rule about aperture numbers included in Webobs, or even better, the observer should make the extra key strokes.

don't do it
paw's picture
Joined: 2010-08-07

Hi all,

My vote is no! No more info is needed. 'Not many key strokes' is still a lot of key strokes when doing a long night of visual observing. I average negatives at one per minute or even more frequently, and positives one every two minutes.

It can't be a default either, because eyepieces change a lot, at least in my case, depending on conditions.

The 'America-centric' aspect of data entry, and I'm NOT saying it should be changed,  that causes trouble for some is the illogical month-before-day in the dates. Much more significant! But for aperture in Australia, a suposedly metric country, telescopes are routinely discussed in inches by marketers, astronomers, shops, and so on, (probably because the American market is so big?) so that's not a problem. But please - no more key strokes.


Power & Aperture
WWJ's picture
Joined: 2010-08-06


Not a lot of enthusiasm! Well...we did try. Never suggested this should be obligatory. Am perplexed about the apparent ambiguities over units. The base plate on binoculars will show something like...”10x50”. It's universally understood that this means a magnification of ten times with an aperture of fifty millimetres. In the same way when Mike's using his “Linnoscope”! With the 3.7mm Ethos eyepiece; we'd expect to see “500x500”.Impressive!

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