Astroimaging Equipment Help, Advice Would be Much Appreciated :)

[LunarLight]

Hey guys

So I have been using my scope for a while now and have been practising with astroimaging with some nice results. I am currently using a skywatcher 200P with a RA tracking EQ5 mount together with a Nikon DSLR camera. I have had fun imaging with this set up but have noticed I can really only take 1 minute subs before star trailing becomes and issue. This interferes with deep sky objects which require much longer subs.

Its time to get into auto guiding I think but I am pretty clueless about the equipment and so I have a few questions.

Do I need to replace my mount with say a heq5 pro synscan (because it comes with a port for the auto guider) or and EQ6 synscan to deal with the extra weight of a guide scope etc?

As I dont know ...well anything about auto guiding can someone tell me what equipment I would need? preferably at the budget/moderate end of the scale

Also I dont own a laptop so I cant use that to control the systems. are there systems which dont require a laptop or do I also need to purchase one of those to?

Thanks for any advice anyone can give it is much appreciated.

Mark

[E621Keith]

I think a 200p is a bit to much for a EQ5, so you should consider replacing the EQ5 with a EQ6. HEQ5 Synscan or EQ6 Synscan will accept autoguider.

There are stand along guiders that will function without a laptop.

Such as this one

Celestron NexGuide Autoguider

and this one

LVI Smart Guider

[Black Knight]

Assuming you got an HEQ5 or NEQ6, you would need a guidescope. Many people use a Skywatcher Startravel 80 (ST80) to act as the guidescope. You can pick one of these up quite cheaply from FLO for around £85 for the OTA only. Obviously you would then need either a dual mounting bracket if you were mounting the ST80 side by side, or whatever dovetail arrangement you would need to piggy-back the ST80 on top of your 200p.

An alternative would be to go the DIY finder-guider route, as several people on here have done, and you may be able to get away with this with your current mount relatively inexpensively. I was tempted to go down this route, but in the end decided to go the whole hog, upgrade the mount, and side-by-side my scopes. I don't know how well a finderguider would perform with the self-contained autoguiders though.

The QHY5 is a popular and relatively inexpensive (£180-ish) guide camera, and it is apparenlty possible to use webcams as guide cameras as well, although since you don't have a laptop neither of these options may be practicable for you. Is your computer situated a long way from where you observe? If not, you could always run a long active USB repeater cable from your computer indoors to your scope and mount. I bought a 12 metre active USB hub for this very purpose .

[Bukko]

Hi, Mark,

congratulations on getting 60 second unguided subs.

I agree with Keith that an EQ5 sounds a bit tight, it would certainly struggle if you add a guidescope as well.

I have done some deep sky imaging and find most objects can be successfully captured with a series of 30 second frames and stacked.

Too long an exposure leads to saturating the sensor and can detract from the final result.

I assume you are integrating many frames using an an alignment and stacking program?

Personal experience, 800 or 1600 ISO, 30-40 second subs, captured in RAW and loads of dark frames to subtract the sensor noise. Must do the dark frames at the same exposure, ISO and camera temperature as the rest. I find 10 frames is enough for a good noise average.

Binning the frames 2x2 also helps, as you don't really need the pixel count of a DSLR.

Orion Nebula only needs 10 to see good detail, 50 will be so rich.

More challenging targets, such as the Iris nebula will take a hundred, or more.

If you really want to try autoguiding, make sure the guidescope is of good quality. The Skywatcher recommended is a good choice. I use an Opticstar PL130M for guiding, the good size CMOS chip helps with finding a suitable star and is around £50 less than the QHY5 recommended below.

A PC is essential. You don't need some high powered thing, so no need to overspend on it. I have seen the self contained autoguiders and they are just so much more difficult to work with, especially in sky lacking bright stars to centre on...

So, maybe for now, exhaust the potential of what you have got while saving up for the EQ6 PRO/Skywatcher ST80/Laptop/guide camera !!

Good Luck !

Gordon

[LunarLight]

hey guys thanks for the advice I posted a simlar thread in the imaging sections because I didnt think anyone would reply to this post :-D

You guys gave the more or less the same advice as on the other thread. I went for the NEQ6 with the st-80 guide scope. So I am just waiting on the arrival of the equipment

yeah I have been taking images for a while now but for the faint galaxies I find its hard to get much detail unless you take LOADS of 50-60 second subs and even then its a bit of a hassle. I take darks flats and bias with each set to...though im still getting the hang of flats lol!

I have done some research and heard that with objects that get burnt out its possible to take a set of shorter exposures with the longer ones and mask them in photoshop to solve that issue.

thanks for the advice guys