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100 Degrees eyepieces are thay worth it!?


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Hi all my current scope is a Meade 12” sct cassagrain ACF (coma free) 

my current eyepieces consist of 

Exsplore scientific 40mm 68 degree Argon purged 

Televue 27mm panoptic (68 degree ,Delos 10mm 72 degrees and soon to be purchasing Delos 17.3mm 

For visual purposes it seems that the refractor offers wider field of views so owning something like an 100 degree ethos or similar brand would give a space walk type of experience as some have described what the views look like and certain optical systems like the maksutov has a more narrow field of veiw due to the optical design the sct has a similar optical set up as the maksutov however the field of view is slighty better.so for exsample would I actually notice any beneficial advantages of me useing 100 degrees eyepieces.as I don,t mind spending money when I can actually see some visible gain or is 100 degree eyepieces only really gain more benefits in useing a instrument like the refractor which usually is a shorter focal length and designed for more wide field purposes.

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I've moved this to the eyepieces section - it should get more responses there.

I have left a link to it in the original posting location so people will find it from either place.

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On your subject, I'm not sure you will see any benefits with your scope from 100 degree eyepieces, apart from the wider field of view.

You current eyepieces are of very good quality - the Delos are a touch better than the Ethos.

So, unless you really yearn to see that additional true field, there might be other ways to spend your money !

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It’s not really a question of widefield scope or not, it is simply whether you want to see a wider field than you currently get with your eyepieces.

This is a comparison between the 10mm Delos and Ethos in your scope. I tend to agree with John’s opinion that your scope is not about widefields, so the Delos May be the best option.

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20 minutes ago, Supernova74 said:

For visual purposes it seems that the refractor offers wider TRUE field of views so owning something like an 100 degree APPARENT FIELD OF VIEW ethos or similar brand would give a space walk type of experience as some have described what the views look like and certain optical systems like the maksutov has a more narrow TRUE field of veiw due to the optical design the sct has a similar optical set up as the maksutov however the TRUE field of view is slighty better.so for exsample would I actually notice any beneficial advantages of me useing 100 degrees APPARENT FIELD OF VIEW eyepieces.as I don,t mind spending money when I can actually see some visible gain or is 100 degree APPARENT FIELD OF VIEW eyepieces only really gain more benefits in useing a instrument like the refractor which usually is a shorter focal length and designed for more wide field purposes.

You're conflating true field of view with apparent field of view.  A telescope's focal length determines it's maximum true field of view.  In general, refractors generally have shorter focal lengths than SCTs and especially Maks.  Newtonians tend to span all focal lengths.  A telescope's true field of view determines the maximum amount of sky visible through it in one view.  This has nothing to do with the apparent field of view of the eyepiece used to view that image.

An eyepiece has a focal length and an apparent field of view.  The focal length determines the magnification.  Just divide the telescope focal length by the eyepiece focal length to calculate the magnification for the combination of the two.  This determines the image scale.  The apparent field of view is how big the image circle appears to the eye, and thus how much of the image at a given magnification is visible in one view.  To a first approximation, divide the eyepiece apparent field of view by the magnification to determine the true field of view on the sky of the combined system.  Thus, a 40mm eyepiece with a 50 degree apparent field of view would show approximately the same true field of view as a 20mm eyepiece with a 100 degree apparent field of view.  The exit pupil would also be half as big in the latter creating a darker sky background.

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