Author Topic: SCT vs DOB  (Read 115 times)

Greg Fleming

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Re: SCT vs DOB
« Reply #15 on: January 13, 2018, 03:58:22 AM »
Thanks for all the great suggestions. I think maybe I'm trying to do too much with one scope. I live in the country and my driveway is gravel so it can be soft or snow covered so I considered putting my tripod w/ scope on wheels, but it didn't seem practical. The center of gravity is high and somewhat daunting (at least for me) if the ground is not smooth. I have/am considering putting my scope in a POD; that would make it easy for home (no moving & always ready to use).

I agree any 12" scope will have heavy parts. It seems like a Dob intrinsically will have a lower center of gravity, especially if it is a truss style (assuming I move it and then assemble). Also, I don't have to lift the mirror, I can roll it. This would be very helpful when camping. As many of you suggested, I need to do some more homework. Thanks again for all the suggestions. This is my first time using this forum and I'm amazed at the speed of response.

faubloginac

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Re: SCT vs DOB
« Reply #16 on: January 16, 2018, 12:23:40 AM »
I would agree with your COG assessment. A Dob would have a lower COG but you still have to roll over gravel so you would want a cart that can take big wheels. So just make one. Should be easy enough if you are at all handy.

13" wheels
http://www.homedepot..._-204405113-_-N

Those would probably do OK on gravel or grass.

A second thought is to go for a smaller scope to supplement your big scope. I have an 8" Dob and an 80 mm refractor as my grab and go.

Maybe a 6" Dob that you could lift and carry. Perhaps a tabletop unit. Will find your targets but you have to track manually. I have the 8" XT8i Intelliscope.
http://www.telescope...rd=Intelliscope

My eye is on anOrion XX14i or XX14G About as large as I can go and still see the eyepiece at zenith without a stool. Will fit on a cart in my garage and can just clear the garage door.

schorerabhat

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Re: SCT vs DOB
« Reply #17 on: January 16, 2018, 11:36:58 PM »
I have goto on all my dobs...i shot my laser thru a 35mm eyepiece and push the beam coming out of the telescope and goto where i want to look.

writgobetfcoo

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Re: SCT vs DOB
« Reply #18 on: January 17, 2018, 01:08:24 AM »
I will go with the Dob any day. Cheaper, versatile and cools much much faster than SCT. Go with the Intelliscope version if your budget permits.

Chris Harwood

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Re: SCT vs DOB
« Reply #19 on: January 18, 2018, 08:49:31 AM »
I would like to learn to star hop. Any suggestions on how to best teach myself? Thanks.

cludertypos

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Re: SCT vs DOB
« Reply #20 on: January 23, 2018, 02:13:21 AM »
Quote
I would like to learn to star hop. Any suggestions on how to best teach myself? Thanks.

One can buy a planisphere to help you find constellations. Also, astronomy magazines usually have a monthly star chart in them. Although not very detailed, they will at least help you find/learn the constellations. Norton's Star Atlas is more detailed, so is Sky & Telescope's Pocket Sky Atlas. Brent Watson is the author of several finder charts one can use in the fieldto locatemore well known objects like Messier objects, etc.His charts arevery helpful if you have a Telrad finder on your scope. Other charts that come to mind are the Cambridge Star Atlas and Sky Atlas 2000.
Andy

trafefupgi

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Re: SCT vs DOB
« Reply #21 on: January 25, 2018, 03:22:51 PM »
I find that there are 3 important elements to enjoyable star-hopping.

First, a good right angle, correct image finder. I have several nice 50mm RACI finders. These give a nice view of star fields that match what you see on your map.

Second, a good star map that is comfortable to use in the field. My favorite is the S&T Pocket Sky Atlas.

Third, a comfortable seat and a small table. It is nice to be able to trace your star-hop on your star map, kinda like hiking in the woods.

As a bonus, a book designed for star-hopping, like Turn Left at Orion.

For example...
You can star-hop with a GoTo scope. The same rules apply, you just use your GoTo to slew to your starting point, and then use your finder and hand controller to go from there.




nuitropheneg

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Re: SCT vs DOB
« Reply #22 on: January 25, 2018, 11:06:48 PM »
A little wire hoop scaled to match the field of your finder is a handy little tool...
It makes a dandy bookmark too!


glyctetabung

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Re: SCT vs DOB
« Reply #23 on: January 30, 2018, 01:05:56 AM »
Quote

I find that there are 3 important elements to enjoyable star-hopping.
First, a good right angle, correct image finder. I have several nice 50mm RACI finders. These give a nice view of star fields that match what you see on your map.
Second, a good star map that is comfortable to use in the field. My favorite is the S&T Pocket Sky Atlas.
Third, a comfortable seat and a small table. It is nice to be able to trace your star-hop on your star map, kinda like hiking in the woods.
As a bonus, a book designed for star-hopping, like Turn Left at Orion.
To add to what John has said:

- Patience. I consider patience, perseverence and curiosity to be the most necessary virtues to be an amateur astronomer. Star hopping is not just a means to an end, each star hop is a journey, it is a learning experience, a joyful experience.

- Telrad: A Telrad is powerful tool that can make pointing the scope very simple. It projects a 1/2, 2 and 4 degree circles against the night sky, you match those circles with a chart and you are done.

- These days electronic charts like Sky Safari 4 or 5, Plus or Pro on a smart phone or tablet are powerful star hopping tools. They can offer deeper databases with far more information than any chart with a planetarium that shows you the sky, the way you see it wherever you are and at the exact moment. No need to figure out the chart rotation. They are highly customizible, zoom, adjust the magnitudes of the stars shown, the DSOs shown. Touch an object and a great deal of information is shown. One can do searches, build observing lists, I often do that right in the field, sitting on my chair..

Sky Safari is great for double star observers, you can search a constellation, multiple constellations, the entire sky for doubles of a variety of types. You can set the magnitude range, the separation range, convert the search results into an observing list and even choose to have each object on the list circled in the planetarium view.

Another nice feature is the compass view. For a device with a compass and one of several sensor types, you hold the device up to the sky and it will align itself with the sky, showing what you are seeing.

- The main thing I think is that one should approach star hopping as a worthy experience in itself. I just enjoy it, even with my scope on GOTO mounts, I star hop, it is just plain fun.

Jon Isaacs

Rick Reiter

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Re: SCT vs DOB
« Reply #24 on: January 30, 2018, 03:11:17 AM »
Quote
I would like to learn to star hop. Any suggestions on how to best teach myself? Thanks.

Star hopping 101 – Video play listhttps://www.youtube....6B0AD5D29A76981

Star hopping guidehttp://www.nightskyi...m/star-hopping/

Star Hopshttp://astrobob.area...ned-from-stars/
www.daviddarling.info/encyclopedia/A/Andromeda.html

Turn Left at Orion - presents realistic examples of what you will see in your eyepiece. Also provides recommendations on targets based on whether you are using binoculars, small telescope or large telescope.
​Lots of good information on telescopes too. My favorite reference book.
http://www.amazon.co...n left at orion

Robert Bass

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Re: SCT vs DOB
« Reply #25 on: January 30, 2018, 06:09:53 AM »
Quote
I would like to learn to star hop. Any suggestions on how to best teach myself? Thanks.

Get the book called, Messier Marathon by Harvard Pennington , it'll teach you the geometric method of starhopping with a telrad with 1/2 , 2 and 4 degree circles, previously mentioned by Jon. It also shows you the views thru a straight and right angled finder scope and finder stars. It also explains all the Messier objects and their appearance thru the eyepiece, FOV and magnifications, etc. 29.95 at most places and well worth it. If you've ever looked at a road map and used the scale , inches to miles, same concept here except your using the telrads red circles on the sky to scale off distances. You want a more detailed explanation, PM me, i'll explain it to you. Another nice atlas, Sky and Telescopes pocket atlas , inside the front cover is a scaled telrad circle you can overlay the charts with. In really light polluted areas its not as effective , but if you can see to Mag 4 stars it'll work. The book Nightwatch is another good primer, Terrence Dickinson.

Kunjan Blanco

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Re: SCT vs DOB
« Reply #26 on: January 30, 2018, 11:50:36 PM »
I also heartily recommend the RACI finder. I starhopped for 20 years and nothing improved the efficiency more than the RACI.

I'm in construction, so I read plans/blueprints all day long. I can read them upside down, over my shoulder, etc, at any angle or orientation. But for some reason, it made my head spin when going back and forth from star charts to the reversed image of a normal non-CI finder. Plus, I stargaze for relaxation and enjoyment, not having to spend brain waves re-positioning things in my head. The CI finder matches the charts, making starhopping a breeze.

ryepittimy

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Re: SCT vs DOB
« Reply #27 on: January 31, 2018, 02:51:19 AM »
Quote
I also heartily recommend the RACI finder. I starhopped for 20 years and nothing improved the efficiency more that the RACI.

I'm in construction, so I read plans/blueprints all day long. I can read them upside down, over my shoulder, etc, at any angle or orientation. But for some reason, it made my head spin when going back and forth from star charts to the reversed image of a normal non-CI finder. Plus, I stargaze for relaxation and enjoyment, not having to spend brain waves re-positioning things in my head. The CI finder matches the charts, making starhopping a breeze.


I used straight through finders for many years and somehow I was able to deal with the reversed-upside down (or rotated if you want) image. I tried RACI finders but I was so used to the straight throughs that they were counterintuitive.

But last year, I desired to switch over if I could and I will say that RACI are more comfortable but also much easier to use with charts. The only downside is that I am I looking at 90 degrees to the direction the scope is pointing so a red dot finder or Telrad is almost a necessity to get pointed in the right direction. My scopes are equipped with Telrads sobthat s not an issue.

Jon

Myron Apostolics

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Re: SCT vs DOB
« Reply #28 on: January 31, 2018, 04:16:57 AM »
The problem that I had with star-hopping was that I learned how to do it way back in the 60's and 70' using homebuilt telescopes that did not even have a finder, so you had to star-hop through the telescope, usually with a Kelner eyepiece. The field of view was so narrow that it made each hop a leap of faith. Very slow and frustrating, though back then it was all I had and I didn't know any better. Jump ahead to the Modern Era, a good 50mm RACI finder is soooooo nice, it has made star-hopping a joy. I've either added a 50mm RACI finder to all of my scopes or I have at least added a Vixen receiver so that I can move one of my RACI finders from one scope to another.

Fun stuff.

P.S.

My new best friend is my Starbound chair. My back instantly thanked me.

P.P.S.

Every now'n then I'll use SkySafari at the scope. It is nice as it lets you flip and rotate the map to match my finder and scope. However, I find the Pocket Sky Atlas to be much more comfortable, easier to use, and a great match for my finders.

ridafimist

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Re: SCT vs DOB
« Reply #29 on: January 31, 2018, 07:38:06 AM »
Quote
Quote

I also heartily recommend the RACI finder. I starhopped for 20 years and nothing improved the efficiency more that the RACI.

I'm in construction, so I read plans/blueprints all day long. I can read them upside down, over my shoulder, etc, at any angle or orientation. But for some reason, it made my head spin when going back and forth from star charts to the reversed image of a normal non-CI finder. Plus, I stargaze for relaxation and enjoyment, not having to spend brain waves re-positioning things in my head. The CI finder matches the charts, making starhopping a breeze.


I used straight through finders for many years and somehow I was able to deal with the reversed-upside down (or rotated if you want) image. I tried RACI finders but I was so used to the straight throughs that they were counterintuitive.

But last year, I desired to switch over if I could and I will say that RACI are more comfortable but also much easier to use with charts. The only downside is that I am I looking at 90 degrees to the direction the scope is pointing so a red dot finder or Telrad is almost a necessity to get pointed in the right direction. My scopes are equipped with Telrads sobthat s not an issue.

Jon
I use a RACI finder on my C8 along with a red dot pointer just to aim my finder scope. (I recently switched from a red dot to a dimmed down Celestron Star Pointer Pro, but that's a minor detail.) If I can see my target or it's exact location in my RACI finder scope, I'm there, as easy as aiming a rifle. More often, I wind up finishing my starhop to a DIM object with my low power eyepiece using little FOV circles on clear plastic on the Uranometria 2000 atlas... Simple, just on a smaller scale. The place where a roughly polar aligned SCT is nice is that it gives the sky an "up & down" and "sideways" using my RA and Dec knobs. I can just turn knobs and count off FOV's til I'm there.
 Marty