What Do I Need For Widefield Imaging

Keshdogga (Casey) · #1 09-04-2011, 09:26 PM

Hey IIS It's been a while,

I don't know about everyone else but I've had no chance in the past month to get out and image but It's got me thinking about what else I can do with with my gear. I'm really interested in DSLR widefield imaging but have never had the chance/ability to try It. I understand I would need some way to connect the DSLR to my mount (either by piggyback or some other means) so my question is how should I go about this? Blue tack was the first to come to mind but I somehow think it might not be enough

I use a Canon DSLR if that makes a difference.

And Ponders, if you're out there and happen to stumble on this I'd really like to know where you got that nifty little gadget you have attatched to the aluminium base plate that you use when widefield imaging.

So if anyone has any advice on widefield imaging they'd like to pass down I'd love to hear it

Cheers,
Casey

jjjnettie (Jeanette) · #2 09-04-2011, 09:30 PM

What do you need for wide field imaging??
Clear skies!!!

Keshdogga (Casey) · #3 09-04-2011, 09:36 PM

Tsk tsk not much of that around now jjj

[1ponders] (Paul) · #4 09-04-2011, 09:42 PM

What do you need for widefield imaging; clear skies to start with. I'm not home and its clear skies.

don'tcha just love it.

I have a manfrotto ball head Casey. I think from memory a 484R, but I'd have to find it first. There are plenty out there. I know h0ughy has a great ball head. Mine will just hold a DSLR and moderate lens (135mm) relatively comfortably. It needs to be of good solid quality if you are considering going much longer that 100-135mm. If Dave see this he might still have a link for it.

However 135mm while still of moderate FOV to go Widefield you have roughly choice of from 17-24mm Canon, not a lot done at 35mm but could be a good focal length if you can find a good lens. The Canon 50mm f/1.8 (nifty fifty) is usually a good starter if you can find the better version. Then there is the Canon 85mm f/1.8. Both need to be stopped down a bit (find the 85 a bit more chromatic) but they can produce great results. Not many zooms do well unless you are prepared to stop down considerably or spend a bit of money. Go for primes rather than zooms if possible.

Apart from that, very good polar alignment so you can go unguided. Nice and simple

Keshdogga (Casey) · #5 09-04-2011, 10:28 PM

Thanks Paul

It doesn't look too clear from nambour tonight so i don't think you're missing out too much. I have the stock Canon lense (17mm - 24mm) so will that do? Aside from that I'll have to look around for some suitable ball heads

Is there any place you recommend I check out that sells them? Oh and also where would i attach the ball head to lol?

h0ughy (David) · #6 09-04-2011, 10:31 PM

you need to track if your doing 135mm or higher, but you can get away with some shorter shots with the smaller lenses unguided. the ballmount is a KB3 Benro

Keshdogga (Casey) · #7 09-04-2011, 10:48 PM

That's quite the setup you had going there H0ughy

When was that taken? And thanks for the tip

I'll probably be be getting my polar alignment nice and accurate in any case.

A23649 (Nathan) · #8 10-04-2011, 11:38 AM

i just got one of those bendy tripods, tied it around a tree branch and started shooting

AdamJL · #9 10-04-2011, 01:14 PM

Hi Keshdogga

I took this last night north of Lithgow. I used a 5D, 24 f/1.4 and a sturdy tripod with cable release.

You don't need too much to do widefield so long as you don't do exposures for too long, otherwise the stars begin to trail. Which of course, is an artform in itself

http://adamlawler.smugmug.com/Astrop...08_yoQiF-M.jpg

AdamJL · #10 10-04-2011, 01:17 PM

Quote:

Originally Posted by h0ughy

you need to track if your doing 135mm or higher, but you can get away with some shorter shots with the smaller lenses unguided. the ballmount is a KB3 Benro

oooooo, an Astrotrac

How do you find it?

Keshdogga (Casey) · #11 10-04-2011, 10:59 PM

Great Pic you have there Adam

How long was the exposure(s)? Also, given I have a tracking GEM how long could I push my exposures? I'm really looking for some detail to come out in the shots so how long can I go before I start to over expose?

h0ughy (David) · #12 10-04-2011, 11:01 PM

Quote:

Originally Posted by Keshdogga

That's quite the setup you had going there H0ughy

When was that taken? And thanks for the tip

I'll probably be be getting my polar alignment nice and accurate in any case.

queensland astrofest last year

h0ughy (David) · #13 10-04-2011, 11:02 PM

Quote:

Originally Posted by AdamJL

oooooo, an Astrotrac

How do you find it?

i now own 2

[1ponders] (Paul) · #14 11-04-2011, 06:32 AM

Casey here's a couple of simplified formula for working out how long to expose without tracking.

From 0 deg Dec to around -/+ 60 deg: Tsec=700/FL of lens
From 60 deg Dec to pole: Tsec=1000/FL of lens

If you are tracking on your HEQ then you won't be constrained by trailing but more likely light pollution.