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BHZ or BST


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Partly personal choice, not everyone gets on with zooms. The downside is that they give the least field of view (AFOV) at their lowest power so the Starguiders will outdo the BHZ, in that respect, at all except highest power. The upside is convenience of not swapping EPs. Usual advice is to get a low-power EP for maximum field-of-view to complement a zoom, e.g. 32mm Plössl.

Not sure of your scope details but BHZ + Barlow gives down to 4mm, which is maybe too much magnification?

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The true answer is that only you can answer that with experience.

 

The Starguiders will be wider in apparent field from 16-24mm but otherwise it's a toss-up.

The zoom gives you the option of the perfect magnification for conditions, but the individual eyepieces will allow a change of magnification

without all the in between magnifications you don't want.

In other words, when you want to change the size of an object in the field by increasing magnification, you rarely want to change the magnification 5% or 10%--you want the change to be substantial and give you

an entirely different view of the object.  That can be nicely accomplished with, for example, a 40% change in magnification between eyepieces.

The Zoom hits all the points in between and requires more adjustment to find the increase you were looking for.

If you have a zoom from 24mm to 8mm, you have every tenth of a mm focal length in between.

If you had a set, it might run 24mm--17mm--12mm--8mm.  After a short while, you'd already know which other eyepiece to pick for the view you want.

 

A zoom does mean you don't change eyepieces in the focuser, which keeps you in your seat with your eye against the eyepiece.

But, doctors say we should get up and move around periodically for health, so there may be some side benefits from getting up, moving to a table, and selecting another eyepiece from your box.

 

There is no really definitive answer here.  For me, the narrow fields of view in zooms at low powers would keep me using fixed focal length eyepieces for much of the zoom range, and then what's the point of a zoom?

 

My last point is that SCTs have very narrow fields of view intrinsically.  I would argue that eyepieces even wider than the Starguiders might be a better match.

I'd look for eyepieces of 68-70° at a minimum, many of which are available for modest prices.  That way, the fields of view won't seem as narrow.

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I actually have both the Baader Hyperion Zoom and a set of BST Starguiders. I use both of them and it’s really what you like best. In my Maksutov i use my Starguiders for the FOV and in my Dobsonian I seem to use the zoom more. I am actually in the process of getting 82 degree eyepieces to compensate for the limited FOV in my Maksutov 

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3 hours ago, Guest 12green said:

Would Baader Hyperion 10mm @ 68fov be a good high power option over 8/12mms BST?

If you particularly want a 10mm, you might have a look at this one:

https://www.ebay.co.uk/itm/284532210530?hash=item423f70fb62:g:MYgAAOSwLh1hRukg

Discussion here :

https://stargazerslounge.com/topic/386326-ultima-edge-eyepiece/#comment-4170293

 

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On 13/12/2021 at 12:41, Zermelo said:

I bought a couple of the Svbony 10mm Ultra Flat Field eyepieces a few weeks ago and I've been very impressed when using them in both cyclops mode, and with a binoviewer.

There very small and light with no undercuts (hallelujah!), but they feel solidly built and give great views. I got my pair direct from China for the princely sum of £75.40 delivered and I notice Svbony are doing an offer on their website with various products on sale including the 10mm and 18mm UFF eyepieces. I suspect you'd struggle to find better eyepieces around those focal lengths for the money.

The only caveat is that I think Svbony sell direct from China so delivery times are longer than through a UK reseller on eBay and getting a return or replacement in the event of a problem could be a bit more involved.

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It is true that the long established argument between zooms and fixed focal length eyepieces is one of personal choice. My personal choice is both . I like using the zoom on double stars and planets where field of view is not such an issue. When attempting to find the correct mag for splitting a double, swapping ep’s can be a right pain. So a zoom is perfect 

On the other hand, a lof DSO’s require a wider fov which is where fixed come into their own…..so my view is that, eventually, over time, it’s best to have a good zoom (and the BHZ is excellent) and a full set of quality fixed focal length ep’s as well as a quality Barlow 

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A small factor in favour of a zoom which hasn't been mentioned: it's far more convenient if you're observing with a filter. One filter for several different mags rather than swapping it each time you change EP.

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49 minutes ago, cajen2 said:

A small factor in favour of a zoom which hasn't been mentioned: it's far more convenient if you're observing with a filter. One filter for several different mags rather than swapping it each time you change EP.

You can put filters on the end of diagonal and eyepiece adapter barrels rather than on the end of an eyepiece barrel. If putting one on an eyepiece adapter, check that your eyepiece barrels will not contact the filter before using that approach.

 

 

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26 minutes ago, John said:

You can put filters on the end of diagonal and eyepiece adapter barrels rather than on the end of an eyepiece barrel. If putting one on an eyepiece adapter, check that your eyepiece barrels will not contact the filter before using that approach.

 

 

You can....if you have a diagonal or an adapter. I haven't. ☺️

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Not every zoom eyepiece has filter threads.  My Celestron Regal 8-24mm zoom does not as it was intended for spotting scope usage.  I'm guessing the Leica ASPH, Zeiss Vario, and Swarovski zooms don't either since all were intended for spotting scopes.

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