Hi all
Does a refractor scope require more bending to use than a refelector does, given that the eyepiece is on the rear/lower end of the scope rather than the top end like a reflector?
Posted 21 May 2025 - 09:47 PM
Hi all
Does a refractor scope require more bending to use than a refelector does, given that the eyepiece is on the rear/lower end of the scope rather than the top end like a reflector?
Posted 21 May 2025 - 10:24 PM
Fast and smaller refractors tend to have easily managed eyepiece swing, so they tend to be pretty comfy standing or seated. Slower and larger refractors tend to have more eyepiece swing, and tend to put the eyepiece comparatively low for the region of sky that's most likely to have the best transparency, and that requires some extra management. In general, I find the eyepiece swing of small tripod (alt-az) mounted Newts and Dobsonian mounted Newts up to 10" more comfortable and easier to use, even with a static chair. Smaller refractor observing bliss can be attained with faster/smaller refractors by using a photo/video tripod with sufficiently heavy duty crank elevator- this allows you to put the eyepiece exactly at eye height either standing or seated.
Posted 22 May 2025 - 01:33 AM
Some great info.
Thanks!
Posted 22 May 2025 - 01:57 AM
My eyes (since fixed) and bendy things (that can really break in the night) are the two reasons I almost completely dumped visual astronomy. It's the little things that can really impede enjoyment of an extended visual viewing session and discouraging going out in the future.
I use both Newt's and APO refractors for casual visual observing (using a Voyager II manual alt-az mount ... discontinued ... the same as the twilight 1 mount you can purchase today). All my refractors have faster focal ratios (F/6 to F/7). I tend to use an AT28 UWA (82 deg) eyepiece as a finder instead of using finder scopes for this mount. Once tuned (and regreased for cold weather motion) this is a really nice and lightweight manual mount for poking around the night sky. I also tend to quickly adjust the mount to a vertical position before observing (2-d level on the mount head .. you can see this on the bottom 2 scope images) and it allows quick vertical adjustments so I can quickly sweep to find objects.
Note on lack of a finder to ergonomically use a manual scope: I have used a Celestron 9x50 right angle RACI finder on my SCT in the past. It has a 5o field of view - so the scopes below have very similar fields of view with my finder eyepiece. A laser finder (I periodically use) is nice and very ergonomic as long as I can bend enough to view the sky directly. Red-dot finders tend to be less useful in my skies - the bending part is a pain and the pointing accuracy and visibility is poor. A Telrad is much better but is a bit large for these OTA's. Maybe a Rigel quick finder could make sense in the future. I really like just using a decent quality finder eyepiece on these scopes to directly navigate to objects of interest.
The 72 is the most ergonomic setup ... hands down. I suspect a 90'sh mm F/6 refractor would be very comfortable for manually viewing the sky - the perfect grab-and-go with ergonomics and performance .... this sized scope is just outside my price threshold at this time. The Quattro 150P and AT102ED are very different ergonomically (different things are convenient for each) but I consider them tied for ergonomic comfort.
Notice I am using the 150P like a tabletop dob that has good slow-motion controls. I personally like this arrangement much better than a traditional Dob arrangement (and I can swap my scopes around). The 6" Newt side is good enough for me visually ... I rarely get into really dark skies where big Dob advantages can shine ... and my EAA rigs blow away 20-30" Dobs in detail, (color), and reach.
Observing chairs - critical for ergonomic visual viewing of the sky
I have two different observing chairs. An older Canadian "Beer chair". I broke it recently using it in really dumb ground conditions, but it glues back up nicely. I also made a custom observing chair (AT102 image) that has gradually been improved to provide a solid foundation for viewing. I mostly travel with the "Beer chair" and use my custom chair for use at home. My custom chair makes it easier for me to lean back and visually look high in the night sky. This can be a good advantage finding the areas of interest visually for the scopes. Not being able to view high in the sky before even getting to the telescope can really inhibit my viewing pleasure at night.
And a small step stool can be a critical piece for viewing the night sky as we get older ... think about this as a routine part of your observing kit.
Edited by Mark Lovik, 22 May 2025 - 04:07 AM.
Posted 22 May 2025 - 02:19 AM
Hi all
Does a refractor scope require more bending to use than a refelector does, given that the eyepiece is on the rear/lower end of the scope rather than the top end like a reflector?
Edited by quilty, 22 May 2025 - 02:21 AM.
Posted 22 May 2025 - 02:50 AM
Yes. surely a 5" frac and larger is less convenient than a 5 to 9 inch SC or 5 to 7 inch Mak
While a Newt doesn't provide much comfort
That's why I limit myself to an AT102ED for visual. At F/7 is nearer my limit for convenient viewing ... but still works. Smaller refractors have the least bending of all - and it's so convenient to use a single setup to both find and view the objects in the sky. I figure this size is a good competitor to a 5 or 6" SCT or Mak when you consider resolution and light gathering power. It also can view larger patches of the sky at night (when desired).
I consider my AT72EDii much more ergonomic than any SC or Mak ... at any size. It's really easy to setup for grab and go and does surprisingly well for the moon and planets. It's great for brighter comets in the sky, and does a nice job sweeping across all the richness of the milky-way at night. The 102 is not as ergonomic, but goes deeper on the moon and planets, and does a nice job on matching DSO's.
A Newt may not be ergonomic, or very ergonomic depending on the details (here we have a variety of mounting choices). My choice of a 6" F/4 Newt on an alt-az mount with slow motion controls is very ergonomic. Bigger sizes ... maybe not. Then you need to consider that Mak and SCT's ergonomics also change dramatically with size (saw a 14 or 16" SCT at a star party last year ... it was impressive ... but an industrial level effort to setup and teardown).
I tried a 6" Mak for a bit -- the long focal length is great for lunar and planetary. It's garbage for finding objects without some assistance (well setup finders and other junk). The Mak tends to be a less effective choice for deep sky objects. As long as the ergonomics work, a refractor can handle high powers and large fields of view ... maybe not at the same time Mak implementations often are two darned heavy for their own good ... and it's unnecessary for the design. A goto can make things easier - but the manual centering of 3 stars can be the ergonomic pain we are trying to avoid in the first place.
I started visual using my 8" SCT. Its form factor is good for ergonomic viewing, but I rapidly started going in different directions visually. By the time I can be setup and aligned for visual viewing, I can be deep into visual with my little Newt and fracs. The 150P is not much different in form factor than my 8" SCT it's really short and light. I now use my SCT exclusively for EAA/AP. With modern software and plate solving I can be up and running in a fraction of the time I need for a visual setup. The EAA/AP approach completely avoids the bendy things that are ergonomically painful. So I really like my SCT ... and my Schmidt-Newt ... just not for visual. The Schmidt-Newt would be a nightmare visually unless it was put on an elevated Dob mount. I could still use the SCT on my EAA mounts ... I just don't see the need to do all this technical fiddling to make the SCT ergonomic anymore.
A 6" SCT could be an interesting alternative. It's just about the limit for my alt-az manual mount. Dropping from a max field of view from 3-5 degrees (my little Newt and fracs) to 1-1.2 degrees for an SCT makes the ergonomics of finding objects more difficult (needing more than just the OTA's field of view to find the object). I am thinking DSO's here ... the moon and bright planets tend to be easier to find (mostly). Finding something like M10 or M12 (did this last week in the 102mm frac) becomes more difficult if you are using a manual mount and a narrow maximum field of view.
Edited by Mark Lovik, 22 May 2025 - 03:10 AM.
Posted 22 May 2025 - 03:36 AM
Hi all
Does a refractor scope require more bending to use than a refelector does, given that the eyepiece is on the rear/lower end of the scope rather than the top end like a reflector?
Not really. With a reflector, if the eyepiece is at eye level when the scope is pointing straight up, you will have to bend over when viewing nearer the horizon. Same concept with a refractor, but the opposite: if the eyepiece is eye level when the scope is pointing straight up, you will have to move to a higher viewing position when viewing near the horizon. In both situations, an adjustable height observing chair really helps. Or, as has been pointed out, you can put your scope on a tripod with an adjustable central column. One thing I have learned from using refractors is that it is best to set the tripod fairly high. That way you don't have to bend too low when viewing at the zenith. Then, when viewing nearer the horizon, just put the viewing chair in a higher position, or crank up the elevation of the tripod.
Posted 22 May 2025 - 05:07 AM
Does a refractor scope require more bending to use than a refelector does, given that the eyepiece is on the rear/lower end of the scope rather than the top end like a reflector?
Yes, refractors have a terrible problem with eyepiece height compared to Newtonian reflectors of comparable capability. It's possible to alleviate the problem with an adjustable-height chair and/or an adjustable-height mount. But with a Newtonian, the problem is much smaller to start with.
With a refractor, the eyepiece is lowest when viewing the zenith and highest when viewing the horizon. With a Newtonian, it's just the opposite.
When using a scope with a 90-degree viewing angle -- which includes refractors used with star diagonals as well as Newtonians -- your head is above the eyepiece when the scope is pointing horizontally and below the eyepiece when the scope is pointing to the zenith.
With a refractor, your head is below the eyepiece when the eyepiece is lowest and above the eyepiece when the eyepiece is highest, so the two effects reinforce each other. With a Newtonian, they tend to cancel each other.
When I use my 100-mm f/6 refractor on a fixed-height mount, I need to slide the seat of my adjustable-height chair most of its range as I move from the horizon to the zenith. When I use the same chair with my 130-mm f/5 tabletop Dob, which has an almost identical focal length and very similar capabilities, I don't move the seat at all. With my 7-inch f/5.4 Dob I move the seat up and down about 8 inches.
Posted 22 May 2025 - 05:07 AM
That's why I limit myself to an AT102ED for visual. At F/7 is nearer my limit for convenient viewing ... but still works. Smaller refractors have the least bending of all - and it's so convenient to use a single setup to both find and view the objects in the sky. I figure this size is a good competitor to a 5 or 6" SCT or Mak when you consider resolution and light gathering power. It also can view larger patches of the sky at night (when desired).
I consider my AT72EDii much more ergonomic than any SC or Mak ... at any size. It's really easy to setup for grab and go and does surprisingly well for the moon and planets. It's great for brighter comets in the sky, and does a nice job sweeping across all the richness of the milky-way at night. The 102 is not as ergonomic, but goes deeper on the moon and planets, and does a nice job on matching DSO's.
A Newt may not be ergonomic, or very ergonomic depending on the details (here we have a variety of mounting choices). My choice of a 6" F/4 Newt on an alt-az mount with slow motion controls is very ergonomic. Bigger sizes ... maybe not. Then you need to consider that Mak and SCT's ergonomics also change dramatically with size (saw a 14 or 16" SCT at a star party last year ... it was impressive ... but an industrial level effort to setup and teardown).
I tried a 6" Mak for a bit -- the long focal length is great for lunar and planetary. It's garbage for finding objects without some assistance (well setup finders and other junk). The Mak tends to be a less effective choice for deep sky objects. As long as the ergonomics work, a refractor can handle high powers and large fields of view ... maybe not at the same timeMak implementations often are two darned heavy for their own good ... and it's unnecessary for the design. A goto can make things easier - but the manual centering of 3 stars can be the ergonomic pain we are trying to avoid in the first place.
I started visual using my 8" SCT. Its form factor is good for ergonomic viewing, but I rapidly started going in different directions visually. By the time I can be setup and aligned for visual viewing, I can be deep into visual with my little Newt and fracs. The 150P is not much different in form factor than my 8" SCT it's really short and light. I now use my SCT exclusively for EAA/AP. With modern software and plate solving I can be up and running in a fraction of the time I need for a visual setup. The EAA/AP approach completely avoids the bendy things that are ergonomically painful. So I really like my SCT ... and my Schmidt-Newt ... just not for visual. The Schmidt-Newt would be a nightmare visually unless it was put on an elevated Dob mount. I could still use the SCT on my EAA mounts ... I just don't see the need to do all this technical fiddling to make the SCT ergonomic anymore.
A 6" SCT could be an interesting alternative. It's just about the limit for my alt-az manual mount. Dropping from a max field of view from 3-5 degrees (my little Newt and fracs) to 1-1.2 degrees for an SCT makes the ergonomics of finding objects more difficult (needing more than just the OTA's field of view to find the object). I am thinking DSO's here ... the moon and bright planets tend to be easier to find (mostly). Finding something like M10 or M12 (did this last week in the 102mm frac) becomes more difficult if you are using a manual mount and a narrow maximum field of view.
Edited by quilty, 22 May 2025 - 05:15 AM.
Posted 22 May 2025 - 05:37 AM
A possible fix for eyepiece swing in a refractor is to get a tube ring, attach lead weights to it, and clamp it around the eye end of the optical tube assembly when you observe. Egg-shaped lead fishing sinkers are available in one-pound sizes which will do for small refractors, larger ones may require melting some lead in (e.g.) a mini-loaf bread tin and fastening the whole to the tube ring.
Take note that lead is quite toxic, and is a cumulative poison. Try not to touch it, and encase the lead in any tube balancer that you make in some kind of covered container that will keep it away from human skin.
Clear sky ...
Posted 22 May 2025 - 06:02 AM
Edited by quilty, 22 May 2025 - 06:09 AM.
Posted 22 May 2025 - 06:45 AM
SCTs, Maks and most folded/compound designs have the best overall observing comfort.
Many somewhat fast apo refractors in the 130mm F6-F7 and smaller range are very comfortable to use. You must employ a chair that can be raised and lowered and use a diagonal and probably a right-angle finder.
Newtonians that are smaller than say 10" F5 are also very comfortable to use. Again, an observing chair that can be raised and lowered is your best friend.
Obviously, with larger and slower refractors (which will need wide swings to reach various targets) and larger/slower Newtonians (which will need ladders), observing comfort degreases somewhat proportionally to the size of the telescope and with longer focal lengths.
Personally, along with optical finders, I like laser pointers for initial pointing. Lasers can save your neck/back from getting into uncomfortable positions.
For longish lunar and planetary sessions, as long as I'm seated, I'm comfortable; no matter what telescope design I'm using.
Bob
Posted 22 May 2025 - 07:08 AM
I find it helpful to mount 1x finders- I prefer Rigel Quick Finders- further up refractor tubes, often on the dew/glare shield, to reduce contortions. On larger refractors, I can stand comfortably next to the ota and look through the 1x finder. Green laser pointer finders are also a very comfortable and functional option (not at star parties.)
I very rarely use magnifying finders, but when I do, I use a Rigel to point at the jump-off point, then a right angle correct image finder for hopping.
Here's a fun trick for light polluted skies: With the Rigel (or whatever 1x) near the objective end of a refractor, you can comfortably stand next to the ota and use low-power wide-angle binoculars (or a monocular) to look through the Rigel (with one side of the bino); you'll see the bino field with the targeting reticle super imposed on the field.
For most targets though, under moderate light pollution, I can generally triangulate to targets without magnifying aid. Difficult targets, like dimmer doubles in dense star fields, or threshold DSO's, still need a magnifying finder.
Posted 22 May 2025 - 08:53 AM
Hi all
Does a refractor scope require more bending to use than a refelector does, given that the eyepiece is on the rear/lower end of the scope rather than the top end like a reflector?
No. With the proper height of the tripod and mount, plus a nice observing chair, my refractors (and SCTs, etc.) are very comfortable telescopes to use. You don't have to bend over - you simply bow your head to look down into the star diagonal and the universe is right there, in front of you. It's awesome!
Ron
Posted 22 May 2025 - 09:42 AM
No. With the proper height of the tripod and mount, plus a nice observing chair, my refractors (and SCTs, etc.) are very comfortable telescopes to use. You don't have to bend over - you simply bow your head to look down into the star diagonal and the universe is right there, in front of you. It's awesome!
Ron
One thing people need to realize is that you generally want a tripod with adjustable legs if you are using a refractor. I'm always comfortable with my 102mm f/11 refractor. A long refractor does not have to be uncomfortable. I generally adjust the legs only 2 times during an observing session - sometimes not at all. I set the legs where I want them for a region of sky and spend my time in that area. I also have 4 thinner, firm cushions that I can slide in and out on the chair I use while observing. I can make small adjustments up or down with the cushions until my targets require adjustment of the legs.
Another factor to consider is that how much the eyepiece height changes is not just about the f/ratio. Where does the OTA seat in the rings for balance? My 102mm f/11 actually seats with most of the OTA above the rings. In contrast the 115mm f/7 seats more centrally in the rings. So there is not much difference between the two in terms of variation in eyepiece height. For the 102mm f/11 it is the objective end that has the major swing. The eyepiece end varies in height about the same as the 115mm f/7 so I have to adjust the 115mm f/7 as often as the 102mm f/11.
I'm describing use with an alt-azimuth mount arrangement.
Posted 22 May 2025 - 09:51 AM
Most comfortable rig I've ever owned. Megrez 90FD on a Vixen Porta II alt/az. The chair has 6" of vertical adjustment. I never had to bend over. Just adjust the chair height and set my eye over the eye piece. I've always favored short-tube refractors.
Edited by BlueMoon, 22 May 2025 - 06:29 PM.
Posted 22 May 2025 - 11:08 AM
The TeleVue Air Chair is a bit pricey, but every time you use it your back will thank you! I love mine and only wonder why I did not get it years earlier!
https://www.televue...._page.asp?id=70
Posted 22 May 2025 - 12:16 PM
I have been using the Star Bound Observing Chair for about 20 years and it works great. Set your tripod height for the telescope, your personal preferences, and adjust the chair. Then sit down and enjoy the view!
Ron
https://www.highpoin...ir-sb-black-1-2
Posted 22 May 2025 - 12:46 PM
Drum Thrones are a superb alternative: https://gibraltarhar...M82r-MiNzGXPhBk
Posted 22 May 2025 - 01:20 PM
Hi all
Does a refractor scope require more bending to use than a refelector does, given that the eyepiece is on the rear/lower end of the scope rather than the top end like a reflector?
Yes, it usually does, especially in the case of the longer f/9 and f/11 refractors--but it doesn't have to. The best accessory I ever purchased was an adjustable seat observing chair, as has been discussed already here. With refractors--and any scope, really--the idea is to try to keep your back straight while observing. With long refractors that can be accomplished by using some type of pier extension column and extending the tripod legs out far enough such that when the scope is pointing nearly straight upward toward the Zenith you can sit nearly straight up without slouching and look in the eyepiece with the adjustable seat at a comfortable height:
Even with Newtonians an observing chair comes in quite handy. While the eyepiece does not swing through as large an arc as it would with a refractor of the same focal length, the observing chair can be positioned so that your back is straight pretty much all the time:
Edited by Oldfracguy, 23 May 2025 - 12:17 AM.
Posted 22 May 2025 - 02:11 PM
I consider my AT72EDii much more ergonomic than any SC or Mak ... at any size.
Have you used a small SCT or mak? I love my AT72EDII, it's probably my favorite scope. But it's not more ergonomic than my C5. They are about the same length (12-13 inches) but the 72's focuser moves outward making the system length longer (more so for terrestrial use) and changing the balance.
The Synta 4" mak I have is shorter yet (~12 inches), and the 5" mak is slightly longer than the C5 (~15 inches). In practice all of these scopes are pretty similar in their ergonomics. Even my C8 is only 17 inches so still not too far off in range of eyepiece movement.
For manual mounts I prefer a tripod with an adjustable center column for ultimate comfort.
Now comparing a Newtonian to a refractor, I will add the caveat that I haven't really used a Newt much. But it's hard for me to understand why the Newt (whether on a traditional mount or on a dobsonian mount) would have less movement than a shorter f/7 refractor. Besides the typical longer length of the Newt (more aperture) aren't they mounted further away from the eyepiece?
Edited by maniack, 22 May 2025 - 05:47 PM.
Posted 22 May 2025 - 05:10 PM
Posted 22 May 2025 - 05:59 PM
A good observing chair (that will go to a sufficiently low level) and a diagonal take much of the 'yoga asanas' out of observing.
Two diagonals work even better. It's a different experience using them.
Posted 22 May 2025 - 06:01 PM
Yes, refractors have a terrible problem with eyepiece height compared to Newtonian reflectors of comparable capability. It's possible to alleviate the problem with an adjustable-height chair and/or an adjustable-height mount. But with a Newtonian, the problem is much smaller to start with.
With a refractor, the eyepiece is lowest when viewing the zenith and highest when viewing the horizon. With a Newtonian, it's just the opposite.
When using a scope with a 90-degree viewing angle -- which includes refractors used with star diagonals as well as Newtonians -- your head is above the eyepiece when the scope is pointing horizontally and below the eyepiece when the scope is pointing to the zenith.
With a refractor, your head is below the eyepiece when the eyepiece is lowest and above the eyepiece when the eyepiece is highest, so the two effects reinforce each other. With a Newtonian, they tend to cancel each other.
When I use my 100-mm f/6 refractor on a fixed-height mount, I need to slide the seat of my adjustable-height chair most of its range as I move from the horizon to the zenith. When I use the same chair with my 130-mm f/5 tabletop Dob, which has an almost identical focal length and very similar capabilities, I don't move the seat at all. With my 7-inch f/5.4 Dob I move the seat up and down about 8 inches.
You need to specify "Dob" Tony, not "Newtonian". Put that 7" Newtonian tube of yours on a German equatorial mount and then lets have the conversation about convenience. Refractors are very comfortable to use when properly equipped, I know because I have them in sizes from 65mm to 150mm
Clear Skies,
Brian
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