Do I need tracking to image the sun with a PST?

[csb]

At the moment I have the Coronado mounted on a EQ4.

I haven't been able to do any imaging yet due to waiting for a laptop part to be returned, as it was faulty.

So, 2 questions :

Do I need tracking to do imaging?

Would a Celestron Nexstar mount (from a Nexstar 114GT) be suitable? - I realise I will need an adapter plate)

[[1ponders]]

Depends on how you are going to image Craig. Using a DSLR then you can do without, using a webcam then yes you do. What do you need your laptop for? Can't you operate the mount from a hand paddle?

[csb]

Hi Paul

I'll be using the DMK - hence the laptop.

Why do I need tracking with the DMK but not a DSLR?

[[1ponders]]

The DSLR will take a single image and then you can recenter the solar disc for the next shot if it has moved significantly. With the DMK you will only get short bursts of AVI to work with as the solar disc moves across the fov. You can get away with that and then stitch the AVI together with Virtual Dub or Bink and Smacker before processing in Registax, but it is much more work.

[csb]

Oh, ok that's what I kinda thought would be the case. I was wondering if just hand-tracking would be ok, but from the last part of your response, I would rather have tracking.

Found some PST's mounted on Nexstar and another Celestron single-fork mount. Seems great.

If I do mount on a Nexstar GoTO mount, do I need to consider the distance of the objective from the pivotal centre of the mount? (I assume not because I haven't found this Q posted/answered on the Net).

Has anyone got a nexstar mount or similar for sale?

[[1ponders]]

If all you need it tracking then I can't see why the Nexstar mount can't be modded to take the PST. Sounds like a great idea. As for objective/pivot point, you probably won't be using goto so I doubt if it will matter, all you want is the tracking.

[csb]

Then the Nexstar 60 SLT seems what I will order. Andrews Comm have them for $400 including postage - great price.

Thanks for your help, Paul

[[1ponders]]

Not bad. Do you have any idea on how you are going to the PST yet or are you going to just play it by ear?

[csb]

Are you asking how I will mount the PST? - your post has some words missing.

I will wait till I get the mount.

There is a product called Ray's Brackets that will do the job but it's not available here & will cost probably about $100 with shipping.

Also I found someone has used a dovetail plate with mounting rings that works well.

Actually I am wondering about the pros & cons of using the Nexstar or fitting a motor drive to my EQ4 mount.

Perhaps I should start another thread and get some more advice. I'd especially like to hear from people that have used the Nexstar mount.

[[1ponders]]

I was using an EQ3 with single RA motor, but have moved up to the EQ4 . Very easy to use. :thumbsup:

[csb]

Ah, I actually have an EQ3 - Celestron CG4.

So is what is difference between these 3 mounts that makes you say the EQ4 is "very easy to use"?

[[1ponders]]

I gather you have the HD-102EQ refractor on the EQ3?

Actually I meant the EQ setup is easy to use. I find it easy to use as there is no mucking around with menus when you start it up. Once I have polar aligned it at night, marked the spots on the concrete where is goes, all I have to do is plonk it in place and away I go. Swing it around to the sun and start imageing. Automated goto is not really needed with the sun, besides which star are you going to use to align on ;).

I prefer the EQ 4 now as I bought it with both RA and DEC motors for easier fine adjustment. I can also carry either my ED80 or 102EQ for white light observing/imaging with the pst piggyback much more easily than the EQ3 with less "wobble"

[rumples riot]

It you plan on imaging the sun in Ha and want to use the PST to do it, then yes you need tracking to get nice images.

Just my opinion.

[csb]

Thanks Rumples

I've just paid for a used nexstar mount.

It will be allright, I think, for my imaging.

Actually, a member here read my desire for this mount, without ota, and offered it to me. Quite fortunate there for both of us. Thanks MikeyB.

1Ponders, I got the mount with a 6" Reflector. But have now sold the scope and only have the PST. Probably late I will get a refractor similar to the 102.