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Using refractors for Deep Space Observing

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#1 aa6ww

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Posted 25 April 2012 - 03:10 PM

Do many out here use refractors for deep space observing? Over the years, I've started to move away from my largest scopes in favor or smaller more portable (somewhat) scopes for deep space hunting. These scopes almost always end up being refractors because I love the pin point stars they offer and wide field views. Of course there are still times when the skies are very dark and I take a journey to my dark site location, then I have to set up my biggest SCT, but generally, I find myself moving more toward using my refractors even for deep space observing. My 150mm and 180mm refractors are very fun to use, and still have plenty of aperture for deep space hunting. Maybe unlike most, I find myself more challenged looking for dim objects in my smaller scopes than finding the urge to want larger and larger scopes to dig out distant galaxies.
That seems to be my latest approach to this hobby.
One of my friends calls it "The less is more" mentality. Though my 180mm Refractor is quiet a beast, its still a feather weight compared to my 11 and 14" SCT's. Do others seem to enjoy this approach to astronomy also?

...Ralph in Sacramento

#2 desertlens

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Posted 25 April 2012 - 03:45 PM

Call be crazy (or masochistic) but I enjoy DSOs with an 80mm Triplet. Less aperture presents an interesting challenge and wide field context. Charles Messier certainly did a lot with small refractors.

#3 JIMZ7

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Posted 25 April 2012 - 03:57 PM

Nothing wrong with DSO using refractors. 100% clear aperture & sharp images at lower power. I had a Orion 100mm f/6 & Antares 105mm f/6.3 RFT's & they were fun because of the portability each of them provided. When using 2" eyepieces with 3 or 4 degree fov viewing-it's "jaw dropping" to say the least.

Jim :refractor:

#4 Refractor6

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Posted 25 April 2012 - 04:02 PM

One of my favorites ways to observe when far away from light pollution is with bigger achros. In the past i've suprised myself on more than one occasion on what i've managed to pull in at the ep of my 152 f/6.5 achromatic refractor...this sometimes observing with bigger scopes of other designs right near by that had more difficulty nailing down the same objects such as some challenging galaxies and such.

Karl {Galaxyman} and Mr. Bill and many other members use larger achromats at dark sites for deep sky object observing and targets. The sharp pinpoint stars and very good image contrast afforded by an achro refractor with good collimated optics especially when you get to a 6" class of instrument can't be beat per aperature for the task at hand in my view.

#5 simpleisbetter

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Posted 25 April 2012 - 04:12 PM

I absolutely enjoy refractors on DSO's and find they make very good scopes for it. I moved from a 12" f/5 GSO dob to a 4" f/7 APO which I happily used for 3.5yrs until just recently moving to a 6" f/8 achro. I much prefer a refractor to a reflector, the views just seem more pure for lack of a better way to qualify what I see and "feel". Refractors also cool down much quicker so you get in more quality observing time. And you really can see plenty with them; whether anyone chooses to believe me or not, I've observed Stephen's Quintet with my 4" on two occasions, both very transparent dark nights. I also find refractors to be lower maintenance and easier to clean when needed. All these plusses are what make up for the lower aperture for me. Now if I had a big 16" dob fixed in an observatory at a dark site like Carol...

#6 hfjacinto

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Posted 25 April 2012 - 04:30 PM

While I like the view through my 120 Apo, aperture rules for DSO's. And here is the killer I use my refractor more, it's just easier to use.

#7 jrbarnett

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Posted 25 April 2012 - 04:35 PM

"Do many out here use refractors for deep space observing?"

Yup.

I have a lot of telescopes, refractors included, at my disposal, including, for example, a 16" Dob and 11" SCT. Nonetheless, 4" and 5.5" refractors get more use for DSO observing than the larger aperture scopes.

If aperture is king (debatable) then contrast must be queen and optical quality, prince. No other design comes close to the efficiency per inch of aperture as a quality refractor. Under all but the most perfect of conditions, larger scopes of other designs introduce some amount of "mush factor" into the image. Sure, Jupiter in the 20" Dob at 300x may show additional belts and bands compared to the TC 140 at 200x, but the planet in the TEC is razor sharp, the limb is crisp and the object has three-dimensional shading. The edges aren't crisp in the bigger scope and the inter-belt transitions are a little hairy, even though there are more of them.

It is the ability to deliver 99% of its capability, 90% of the time that makes me come back time and again to refractors as DSO observing tools. Of course, it just makes me want a bigger refractor. :lol:

This year OFLI, my club, will do a week long dark sky trip, and I'll be taking the TEC 140 rather than the Teeter-Lockwood (though the Dob will go on the late summer observing trip to Pinnacles National Monument again this year).

Good post.

- Jim

#8 hfjacinto

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Posted 25 April 2012 - 04:42 PM

Call be crazy (or masochistic) but I enjoy DSOs with an 80mm Triplet. Less aperture presents an interesting challenge and wide field context. Charles Messier certainly did a lot with small refractors.


I don't know if Charles Messier is a good example everything is his catalog is supposed to be comet like, I guess he needed a larger scope to see that none of his objects look like comets.

#9 Jan Owen

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Posted 25 April 2012 - 04:58 PM

Agreed. That pretty much mirrors my thoughts & experience. :like:

#10 GeneT

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Posted 25 April 2012 - 05:07 PM

You are just a refractor guy. If I had the room, I would add a good 4 inch refractor to use with my 12.5 inch Portaball.

#11 desertlens

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Posted 25 April 2012 - 05:23 PM

I don't know if Charles Messier is a good example everything is his catalog is supposed to be comet like, I guess he needed a larger scope to see that none of his objects look like comets.


Nah... He just needed to see they weren't moving.

#12 ken hubal

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Posted 25 April 2012 - 05:36 PM

I will always take the clear aperture of a refractor to that of an obstructed reflector!

#13 rwiederrich

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Posted 25 April 2012 - 05:39 PM

Refractors are all I use. Since I use a 6"f/15 and a 10"f/15 permenantly mounted in an OB...why would I need to switch? The 10"f/15 is awesome on DSO's. Not to mention the 6"f/15 with its Devany Objective.

Rob

#14 Sean Cunneen

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Posted 25 April 2012 - 05:55 PM

Most of the real "WOW" moments I've experienced with DSO's in this hobby were with my refractor. Using it isn't easy but when it pays off, it pays off big! I can still close my eyes and see the detail in the Whirlpool from my view at the Bootleggers star party 2010. I was on my back in the grass with a too-friendly ant crawling on me...

#15 dscarpa

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Posted 25 April 2012 - 06:09 PM

I've got a very good C9.25 and IM715 but find myself enjoying the WO ZS110 for DSOs just as much. A friend of mine has a Meade 10 and he keeps bringing up the DSO viewing he's done with the ZS. There's just something about the star colors he says. David

#16 John59

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Posted 25 April 2012 - 07:32 PM

I have had many scopes over the years and I have made the full circle back to refractors. Currently I have a really nice 12" Goto Dob but it rarely gets used. I seem to always chose the 152MM refractor. As stated below cools faster than anything else and the views are very pleasant.

#17 Friendly Giant

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Posted 25 April 2012 - 07:43 PM

As you can see from my signature, I currently have only a small (72mm F6) refractor and a 10" dob. I went out with some club members to our favorite dark site a week ago (with both scopes). Obviously a 10" dob has more resolving power and light reach, and yet, I found myself enjoying looking at the brighter galaxies more in the 72mm refractor. I looked at M81/M82 in the dob, then in the refractor (same magnification framing the two galaxies together). I just found the view in the refractor more pleasing (crisper, contrastier). I don't think I'll ever get rid of the dob because there are times you just need that resolving power or light reach, but when I look back on that evening my fondest memories are of the views through the refractor.

I'm actually thinking now of getting a refractor at the midpoint between the two... a 5" scope. Although a 130mm Tak would be nice, it would be very expensive and take a while to cool down. I'm therefore also considering a D&G 5" F15 scope. From what I hear, the D&G would give views comparable in quality at least to a top 4" apo, but would have more magnification reach (and also a little more resolving power owing to the higher aperture). The only thing that gives me pause to go for the long D&G is the mounting requirement and being able to work with that long scope as the eyepiece position moves up and down.

#18 mikey cee

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Posted 25 April 2012 - 07:51 PM

I've just started with my setup. True I don't see any detail but then again I'm under a milky suburban light bubble too. A few of the DSO I've seen of late. Messier objects M65-66-95-96-51 and NGC's 205 and 2309. Thank God my refractor darkens the sky enough I can see them heck if I had a reflector no way Jose' they would be lost in the milky white field! :smirk: Mike

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#19 Vondragonnoggin

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Posted 25 April 2012 - 07:51 PM

Very much enjoy my 5" refractor for DSO's. It just makes things look so good. Well for larger DSO's anyway. I think a 6" is in the plans eventually, but for now the 5" is very lightweight and great for DSO's plus more. Was economical too.

#20 watcher

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Posted 25 April 2012 - 08:05 PM

The only mirrored scope I own,(IM715) I only use for planets. Well OK globs too, but that will change when my 6" F/5 ISTAR arrives. Planning on a 9" F/7.7 refractor that will be for DSO only duty also.

#21 galaxyman

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Posted 25 April 2012 - 11:50 PM

Do many out here use refractors for deep space observing? Over the years, I've started to move away from my largest scopes in favor or smaller more portable (somewhat) scopes for deep space hunting. These scopes almost always end up being refractors because I love the pin point stars they offer and wide field views. Of course there are still times when the skies are very dark and I take a journey to my dark site location, then I have to set up my biggest SCT, but generally, I find myself moving more toward using my refractors even for deep space observing. My 150mm and 180mm refractors are very fun to use, and still have plenty of aperture for deep space hunting. Maybe unlike most, I find myself more challenged looking for dim objects in my smaller scopes than finding the urge to want larger and larger scopes to dig out distant galaxies.
That seems to be my latest approach to this hobby.
One of my friends calls it "The less is more" mentality. Though my 180mm Refractor is quiet a beast, its still a feather weight compared to my 11 and 14" SCT's. Do others seem to enjoy this approach to astronomy also?

...Ralph in Sacramento


Hi Ralph

As Stan (Refractor6) mentioned, I only use my refractors for DSO's, and do get great results.

Jim also points out a bit why refractors do so well.

Over the past couple years I've done some hardcore galaxy observing with the 8", and in particular the ARP's.

I also notice you have an APM 7.1" f/6. Is that the APO or achro? A clubmate does have the 7.1" f/6 achro, and he gets great DSO results with that scope.

You also might want to check http://tech.groups.y...ewithrefractors if interested.



Karl
E.O.H.

Chesmont Astronomical Society - www.chesmontastro.org
Deep Space with Refractors - http://tech.groups.y...ewithrefractors
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Homemade (Parks Optics) 12.5" F/4.8 Dob
TMB/APM 8" f/9 Refractor”The Beast”. One great DEEP SKY achro
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#22 Alan French

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Posted 26 April 2012 - 06:13 AM

An odd topic. Why would anyone NOT use a refractor for deep sky observing?

Even a small refractor can show a lot under reasonably dark skies. And one with a short focal length will provide wide true fields not attainable in most other types of instruments.

Clear skies, Alan

#23 Jim Curry

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Posted 26 April 2012 - 07:33 AM

And you really can see plenty with them; whether anyone chooses to believe me or not, I've observed Stephen's Quintet with my 4" on two occasions, both very transparent dark nights.


No surprise there, I've bagged them with my 140. It took the club's 16" to split the close members but smallish refractors can handle their workload. When you think of the equipment upgrade to go from a 13 mag. limit to 16 mag. the small refractors in a dark sky environment will provide endless satisfaction.

Jim

#24 curiosidad

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Posted 26 April 2012 - 09:36 AM

Alan, I have a LP 66ED / 400mm focal lenght, for this, a Truly wide angle vistas..!! Also I have others telescopes much more Big, but for this observations the small refractor I think it´s THE KING!!

#25 aa6ww

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Posted 26 April 2012 - 09:56 AM

An odd topic. Why would anyone NOT use a refractor for deep sky observing?

Even a small refractor can show a lot under reasonably dark skies. And one with a short focal length will provide wide true fields not attainable in most other types of instruments.

Clear skies, Alan



Over the last few years, I find myself doing more and more astronomy either by myself or with one other astronomer whos never lost the passion for astronomy. Everyone else has fallen out of this hobby because its too much hastle for them to put it the effort to get anything out of this hobby. Since now most of my astronomy is close to home, Ive found myself digging my 6" F/5 Celestron Omni with the XLT coating on the front lens. It gives me 6 clear inches of aperture and excellent field of views. The optics are so sharp for excellent star patterns and deep space also, and its such a lightweight fun scope. Im working on my the Herschel 400 with this scope now, it may takes a few years but its a fun game plan and with Ethos, ES and Nagler eyepieces along with my upgrades William optics 10:1 focuser, my larger scopes and mounts ( I use a GP-DX with this scope) will be spending more and more time at home now. Its gonna be another fun year of astronomy, definately! :yay:

...Ralph in Sac






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