Telescope advice

[milkyjoe]

Hi,

I am a returning member to this site and would like some help with a new scope.

I was outside the other night under a cold, crisp, clear night and was having a go at imaging, with not much success.

I don't have a lot of money to spend, but I would like a simple tracking system so that I can practice my imaging without the dreaded star trails!  I was looking at the Skywatcher Heritage scopes, in either the 90p or 114p Virtuoso; are these any good for imaging, what is the tracking like?

Thanks,

Rick.

[happy-kat]

Having read the No EQ DSO challenge thread I am in the process of trying my Virtuoso mount with just my DSLR and 85mm lens to see if I can get the maximum 30 second exposure length.

This type of mount can never do more as it moves in left/right/up/down increments which do not account for the earths rotation but cloudy nights have stalled my test. I hadn't properly aligned my latitude so I only managed around 10 seconds.

[billyharris72]

As happy-kat has said, you'll always be limited with an AZ mount (though there are some quite nice pics on the forum from AZs). What are you imaging with? If you've a DSLR then what about building a barn door mount? That'll leave you with change from £30 and will support wide field with a focal length of up to about 200mm. Exposures of up to about 10 minutes are achievable with these.

Another option, since you have a couple of scopes already, would be to spend all the money on the mount. You might be able to pick up a used EQ3 and RA drive for a similar cost to the 114p Virtuoso. That will work well with a DSLR and I should think would handle the 102 for 30 seconds or more.

[milkyjoe]

Thanks for your replies happy-kat and billyharris72.

I have just been watching this vid: https://www.youtube.com/embed/oySbet53cnI, and I am quite tempted to buy one as it seems very versatile, or is it not as good as he's making out?!

At the moment, I'm using a tripod with my Canon M and 55-250mm lens attached, but that pic of the Orion Nebula was taken with my SW ST102 with the Canon M attached to it, but my main problem is tracking; I know astrophotography is a very expensive hobby, but that Virtuoso seems like a decent option for people with a limited budget.

I've read the minimum mount you need is a HEQ5 Pro which cost £749 - I can't afford that!!

I will look into widefield photography though billy.

Thanks.

[happy-kat]

This is a great read by SGL member.

Link here

If you were looking at processing software then StarTools (not too expensive) has functions to help remove the chromatic aberration you would get from your ST102.

 

Looking at your equipment why not mount just your dslr and a lens on your motor driven eq1.

If looking second hand money does stretch further on just s mount.

 

[milkyjoe]

Thanks for the link, happy-kat.

That was an interesting read, I will be sure to give that a go!

[Waldemar]

Did you try to make many, many short exposures and stack them?

[milkyjoe]

Hi Waldemar,

No, I haven't taken lots of short exposures, but that is an interesting idea!

Thanks.

[SonnyE]

If you want to image, and not get skidding stars, you will need to get a Go-To EQ type of mount, and also auto guiding.

Unfortunately, they get a bit pricey.

Alt/Az mounts tend to not track well enough for good imaging. They are sufficient for visual observing because your brain is helping your eye to stay on your object.

But a camera is depending on the mount to aim and stay steadily on what you want to image.

I really don't think there is any easily affordable ways around that.

[Davey-T]

I think the best option to get into imaging with a DSLR is the SW Star Adventurer it can do excellent unguided images, I can do 90secs @ 300mm and many minutes at 50mm with mine.

Dave

Couple of examples 300mm lens single 90sec exposures

[milkyjoe]

Thanks for the info, SonnyE.

Davey-T: some nice images.  The SW Star Adventurer looks good. 

[ollypenrice]

The Mak in the video would be fine for fast frame lunar and planetary imaging but for deep sky you need a fast F ratio and, for unguided, a very short focal length. That's why lenses and the Sky Adventurer are such a good idea.

Olly

[happy-kat]

Your EOS-m is a nice camera stick your 22mm lens on it and mount just that on your EQ1.

Get an introvalometre so that you can release the shutter without touching the camera.

Don't extend the tipod legs fully (it will help reduce wobbles).

link here

[milkyjoe]

Thanks for the link, happy-kat.

I was outside last night as the skies were near perfect, I had my camera attached to a tripod with my new 55-250mm is stm lens and tried a bit of imaging; I read somewhere that if you divide 400 by the diameter of your lens this will give you how long you can do a exposure for before you get star trials, but I found this did not work.

I attached my camera to my SW 102 with the help of an extension tube attached so I could achieve focus, but again, tried to do a 4 sec exposure, but still got star trials!?

So I decided to take 20x 1 sec exposures of the Orion Nebula.  I now need to stack them together; I had a go with Registax v6, but it's too complicated to use I found. :-(

[happy-kat]

You have a tracking EQ1 but it will do better I think if it is carrying less weight. So if trying your camera use just your camera and lens.

It is 400 / the focal length of your lens. So 400 / 600 of the ST102 is less than 1 second.

Registax is for AVI video. Still frames use DSS.

[milkyjoe]

Aaah, that's where I went wrong! lol.

Thanks.

[happy-kat]

EQ1 used to take M42 with a camera and a lens.

Link here

How to polar align an EQ1

Link here

Polar scope added to this EQ1 and got over 2 minutes in exposure.

Link here