A New Direction .... AGAIN!!!!

[Stu1smartcookie]

Good evening to you all .

Firstly , i'm so glad this site exists ... i've been talking to my wife endlessly about astro equipment over the last few months and she's all telescoped out !

i have changed direction again and now want to buy a nexstar 5 . I have never owned an SCT before so i just wanted to know if anyone on here had any advice or  first hand experience of these scopes . 

i am choosing the 5 because it has a built in wedge... does that change the mount into a EQ?  Also  it seems a portable scope that can be set up in a few minutes. Also i think it should give decent views . I did dabble with a skywatcher 127 Mak ... is there a lot of difference between the Mak and the nexstar ? Also , how quickly would one of these scopes cool down ... it will be stored in the house so the temperature difference will be considerable in the winter months . 

regards , 

Stu 

[Cosmic Geoff]

Why do you want a wedge? And why do you want the option of turning the mount into an equatorial?  If you need an equatorial, it would be better to buy a German equatorial GoTo at the outset.

SCTs have thousands of happy owners - they work just fine.

No doubt somebody will point out a difference in performance between a C5 and a 5" Mak, but I don't think it will be major.   The C5 should cool down quicker than some other scope types, quicker than the 127 Mak for instance.  Maks are not renowned for quick cooling - they have thick corrector plates.

[Stu1smartcookie]

Hi Geoff ... thanks for the reply , well , the wedge is on this  mount , but celestron actually sell them for their larger scopes as an extra . It certainly isn't the main factor for buying the scope , but , it must have its use ... i really don't want another german eq mount . I live in Herts , just 6 miles from stansted airport and the LP is a pain .. i like the idea of travelling to a darker site , so portability is key . Also i have been made aware that these scopes hold collimation well. I have owned dobs that needed collimating everytime i used them and i got obsessed with it ( i spent 2 hours tweaking mirrors one rainy afternoon lol) . I want visual astronomy , and the chance to take a few pics of planets (mainly) .

[Louis D]

Are you talking about the NexStar 5SE?  If so, it's already fully goto in alt-az, so tipping it with a wedge adds nothing for visual observing except additional vibrations.  In pre-computerized goto days, the equatorial wedge was the only way to track with a fork mount.  That's no longer true.

[Stu1smartcookie]

9 hours ago, Louis D said:

Are you talking about the NexStar 5SE?  If so, it's already fully goto in alt-az, so tipping it with a wedge adds nothing for visual observing except additional vibrations.  In pre-computerized goto days, the equatorial wedge was the only way to track with a fork mount.  That's no longer true.

But , does it stop "rotation" if you use the wedge when taking photos ?

[Starwatcher2001]

I only take "snaps", but I'd think if you want the wedge to be accurate for tracking in just right ascension, and handle field rotation then you'd have to fairly accurately polar align it. As others have said I think that would be better achieved on a proper EQ mount.  Being an alt-az mount, I'm sure it will track fairly accurately even with the wedge in, but likely by using both motors.

The biggest benefit for me of the NextStar (9.25") is ease of setup. I can be up and visually observing in 20 minutes including carting all my ancillary junk outside. Given the lousy weather here, it makes the difference between getting some observing in and not bothering.  I don't think cool down on that scope will be very much longer than the setup time. Get the tube out first and by the time you've got it assembled, aligned, eyepieces ready and a coffee in your hand, you'll probably be good to go.

 

[Stu1smartcookie]

3 minutes ago, Starwatcher2001 said:

I only take "snaps", but I'd think if you want the wedge to be accurate for tracking in just right ascension, and handle field rotation then you'd have to fairly accurately polar align it. As others have said I think that would be better achieved on a proper EQ mount.  Being an alt-az mount, I'm sure it will track fairly accurately even with the wedge in, but likely by using both motors.

The biggest benefit for me of the NextStar (9.25") is ease of setup. I can be up and visually observing in 20 minutes including carting all my ancillary junk outside. Given the lousy weather here, it makes the difference between getting some observing in and not bothering.  I don't think cool down on that scope will be very much longer than the setup time. Get the tube out first and by the time you've got it assembled, aligned, eyepieces ready and a coffee in your hand, you'll probably be good to go.

 

Thanks for the reply ... as i am mostly visual , the photography is just an interesting sideline that i will use . I won't ask about polar alignment as there are YouTube vids out there that can help . 

I agree with you about ease of set up ... i used to get bogged down setting up  my HEQ5 pro and EQ5 mounts only to see clouds rolling in and observation time cut to a few minutes . 

[Louis D]

5 hours ago, Stu1smartcookie said:

But , does it stop "rotation" if you use the wedge when taking photos ?

Yes, it stops field rotation.  But to quote you above:

18 hours ago, Stu1smartcookie said:

I want visual astronomy , and the chance to take a few pics of planets (mainly) .

Neither of these use cases requires the suppression of field rotation in an SCT.  For planets, you takes tens of thousands of very short exposures and use software to select the best images, derotate them, and then align them.  Since there are no diffraction spikes from spider vanes, you don't have to worry about rotating diffraction spikes between frames as there would be with an alt-az Newtonian.  For big Dobs and planetary imaging, folks generally use an equatorial platform to control diffraction spike rotation across frames, at least within one, one hour tracking pass of the platform.

Here's an image of the NexStar 5SE with the equatorial wedge raised:

That doesn't look stable at all.  I've got to think there's lots of flex and opportunities for vibrations to keep ringing through the system.  Any sort of breeze could set it to vibrating like a mechanical clock work.  It certainly would be useless visually in that mode.  Anytime you touched the focuser or bumped the eyepiece, it would take forever to settle again.

Compare it to this older C5+ equatorial wedge:

That thing looks a whole lot more stable with 3/8" metal plates everywhere.  I'd also wager that fork arm is metal rather than plastic.

Being equatorially mounted wasn't an afterthought back then.

[Stu1smartcookie]

yes i see ... and its a point well made , Louis . Iam pretty glad i asked for advice on here regarding this scope .