Gonna pull the trigger and hope the recoil isn't too bad

[Kirscovitch]

After  a bunch of thought and see sawing back and forth whether or not I should or shouldn't do it, I think I'm going to get a 10" dob.

Now I know that I'm pretty new and that I've only had my first scope for a couple months, but there is some reason to my madness.

One reason is that when the sky is not cooperating I'm doing some research and I've made some decisions of what I want to get out of astronomy. As much as AP is appealing and some of the pictures I've seen on SGL are simply stunning, I don't think I have the time or patience for proper AP. Instead of setting up for a shot on a DSO and spending a couple hours taking exposures and dark frames and who knows what else, I could take that time and view a lot of different objects. I work 2nd shift so most nights I don't leave work till 2 a.m. By the time I get home and get the scope outside and let it cool down and get everything set up it's after 3 and the sun will be coming up in a couple hours. My imaging sessions will most likely be for lunar and planetary objects using my Starshoot. 

Another reason is cost. More bang for the buck. And I'm sure most would agree that aperture is key to good a good scope.

And going along with cost is probably the reason that pushed me over the edge to get a new scope so soon after getting the first. Right now I have the funds to be able to get it. At first I was going to wait at least 6 months to a year to get it but I figured that since I have the funds to get it now I might as well do it. 

Yea, most likely it's the newb in me with aperture fever but I know the opportunity is there now. It may not be in a year. 

Now to figure out a way to explain the huge box to the old lady when it gets delivered 

[Minimalist__]

It seems like a perfectly justified and reasonable decision!

If you know that you are going to be a visual astronomer above all else with a focus on DSOs, then a Dobsonian is probably the most appropriate choice. At that point it's just a case of buying as large an aperture as you can afford, and it seems like that's exactly what you did. So, clear skies for when the 'scope arrives!

[Kirscovitch]

Well I haven't done it yet. Waiting on confirmation that the scope is in stock. Problem is that it gives me time to think.... Things like, "I was gonna get the 10 but there is a 12". And it's not that much more." 

[hippie]

I have the 10" skywatcher Dob and am now a convert to dob's   If you can go for the 12" I sometimes wish i did ?, But i have to lug mine up & down stairs  into the car and up again each time i go out with it?, 

Welcome to the Dob club  .

[estwing]

if your moving it a lot,stairs and steps...go 10" if not then go big!!

[Luke]

Just me, but I would take the 10, which is probably different to what I would have said a year ago! In the last year I've changed my outlook a bit, from what sounds most exciting to what is more practical for me, and I'm enjoying things more than ever.

Some nights after a long day at work and with the weather forecast iffy, I ask myself if I can be bothered to put the scope outside to cool down. Then I remind myself what a breeze the 10 is to put outside, and 95% of the time, I put it out. And then I've had some lovely sessions on those nights where it cleared for a while

I'd still be super happy with a 12, I just sway to the lighter weight as 10 is enough aperture for me to have a lot of sky and great sights to pick from. I love my 16, but the 10 always impresses me with how deep it can go for the price I paid.

I may one day go back to a 12 as my workhorse scope, but it would be for a premium 12 that is not heavier than my 10.

I'd say, go with your gut instinct!

[kirkster501]

The 12" is significantly bigger and heavier than the 10".  Even as quite a strong, fit bloke the 12" is heavy and unwieldy.  Had I not got a double garage there is no way madame would have a 12" in the house.  A 10" I could possibly negotiate but no way a 12" !

[Nakedgun]

For DSOs, 44% more light with a 12", that's a lot.

But as Luke said, and like when I had a my 10", it was very easy to set up/take down, which meant it got more use than my 12.5" does today.

Every decision has a price. Good luck. 

[Kirscovitch]

Thanks everyone for the input. I went with the 10. 

Now to find a place to hide it from the missus lol.

[estwing]

congrats and welcome to the dob mob!

[Moonshane]

great choice I think. a 10" dob is a fine instrument.

I agree to some extent with the comments above re having a scope you want to use most often. I have a 16" dob which is fabulous at star parties or when a weekend meets a good clear night but my most often used scope is my 12" f4 as this is so light and easy to set up. I store my scopes indoors and it takes me maybe 5 minutes max to set up any of them but the 12" cools quickly and is much easier to lug back in if it starts raining.

with your 10" you'll be able to observe at low power from just a few minutes after putting it out. the view will improve with more time but don't wait if time is short.

[swamp thing]

Good call on the 10". Great size

But then I would say that

I find a 10" the perfect balance between aperture and portability. It's ready to go in seconds and still delivers a punch at the eyepiece.

[Kirscovitch]

I think I made the right choice. Getting almost 2x the aperture than my 130. The 12 would be nice but I plan on taking it to my nearby dark site so the lighter 10 just made sense. 

The missus didn't seem to put off by the idea of the new addition. All she wanted was a new sewing machine so that was purchased just after 

If she's happy, I'm happy!!!

[Phil Fargaze]

 A man`s best friend is his dob!  I`ve had my bouts of aperture fever but I`ve stuck with the old faithful 10" for nearly ten years now and it has served me well on many an adventure.

Good choice, have fun!

[Moonshane]

happy wife = happy life (other spouses may also apply )

[Kirscovitch]

Seems to me though that with the higher aperture and the way longer focal lenghth (1250 compared to 650) that I might need to rethink my EP selection. Right now my 25 EP gives me 26x but with the new dob it will raise it to 50x. So I picked up a 38mm wide angle EP to go with it. Seemed like a logical choice?

[swamp thing]

Watch your exit pupil size with those long focal length eyepieces Matt

[Kirscovitch]

Watch your exit pupil size with those long focal length eyepieces Matt

Is there a formula I can figure that out with?

[swamp thing]

Exit pupil.

The smallest cross-section through the beam of light from an eyepiece through which all of the light from the eyepiece passes. The observer's eye should be at the exit pupil to see the full and brightest field of view. The diameter of the exit pupil is the focal length of the eyepiece divided by the focal ratio of the telescope. Thus an 18-mm eyepiece will have an exit pupil of 3 mm on an f/6 telescope. A simple way of finding the diameter of the exit pupil for binoculars is to divide the aperture by the magnification. For 7 × 50 binoculars, the size of the exit pupil will therefore be just over 7 mm. If the exit pupil is larger than the diameter of the dark-adapted eye (about 7 mm on average), some light will not enter the eye and will be wasted.

[Kirscovitch]

Exit pupil.

The smallest cross-section through the beam of light from an eyepiece through which all of the light from the eyepiece passes. The observer's eye should be at the exit pupil to see the full and brightest field of view. The diameter of the exit pupil is the focal length of the eyepiece divided by the focal ratio of the telescope. Thus an 18-mm eyepiece will have an exit pupil of 3 mm on an f/6 telescope. A simple way of finding the diameter of the exit pupil for binoculars is to divide the aperture by the magnification. For 7 × 50 binoculars, the size of the exit pupil will therefore be just over 7 mm. If the exit pupil is larger than the diameter of the dark-adapted eye (about 7 mm on average), some light will not enter the eye and will be wasted.

Ok. So that 38mm in the new f5 scope would be 7.6 so thats pushing it.

[swamp thing]

Ok. So that 38mm in the new f5 scope would be 7.6 so thats pushing it.

It is a bit

Better to use higher mag with wider fields. My goto eyepiece in my 10" Dob is a 20mm 82degree AFOV one. This gives the same field as a 32mm 50deg plossl at higher more contrasty power. Kinda win win.

Remember we up aperture to increase image scale. That's the primary reason to get a bigger scope.

[Kirscovitch]

Ok I can understand that. I'm assuming the 20mm is what you use on DSO's?

[swamp thing]

Yes Matt. It gives a real nice power and black sky background.

I very rarely use any eyepiece of lower power than this. It just isn't needed In my 10" f/4.5 scope. Anything that doesn't fit in this field needs a smaller scope, or bins

I often use this eyepiece plus a Powermate (Barlow) and that's it for the evening. A 20mm and a 10mm at 82deg AFOV what else does one need?

[Kirscovitch]

Mind my asking what kind of EP's these are? I've done some searching and the largest afov I can find in a 20mm is 70.

[Moonshane]

it's a 20mm Type 5 Televue Nagler

there's also a 21mm TV Ethos with a 100 degree field.

both quite expensive.