Lovejoy from Adelaide....sort of

swannies1983 (Dan) · #1 23-12-2011, 06:25 AM

I wasn't happy with my spot yesterday morning so I did a bit of work looking at Google Maps. Came across a few potential spots near McLaren Vale. After going for a drive to investigate these spots last night, the first thing I said was "wow, it's amazing how little light pollution there is 20mins away from my home. I think I've found a spot to do some imaging."

Anyways, I made my way back to my spot at around 3.30am. I could already see the comet tail coming up from the horizon. Unfortunately, cloud started coming from the SW. A quick look at the satellite image revealed a bank of cloud, only about an hour wide, would spoil the show

Here's the best I could manage. Shots taken with Canon 400D, using standard 18-55mm lens. Boy it's hard to focus with this lens! Still not quite happy with focus but it's better than yesterday's attempt. Are these lenses capable of getting better stars than what I have shown?

1st and 2nd shots taken at 18mm, 30secs, F3.5, ISO1600. 3rd shot at 50mm, 15secs, F5.6, ISO1600. Not happy with focus but it was a struggle to get that image as I was just about to pack up.

jjjnettie (Jeanette) · #2 23-12-2011, 06:45 AM

Dan, you got a better look in than most of us up north.
To get better stars with the lens, you have to knock your F Stop up a couple of notches. Which means longer exposures or upping your ISO to compensate. It's all a balancing game isn't it.
I like the wider field shots myself. It shows the comet in it's natural environment.

swannies1983 (Dan) · #3 23-12-2011, 06:51 AM

Thanks. I've just added in ISO details. I have been taking them at ISO1600 which is the highest the 400D will go. I see a number of people shooting at ISO3200. Obviously they are newer models than mine.

I had noise reduction turned on in this case. I might try 45-60secs and bump up the F number. I was just concerned about star tails shooting longer than 30secs.

Liz · #4 23-12-2011, 07:48 AM

Well done Dan, some great shots there with the longtailed comet amidst the Milky Way.

swannies1983 (Dan) · #5 23-12-2011, 08:04 AM

Thanks Liz. I was happier with this effort compared to yesterday's (apart from cloud). Just have to sort out camera settings and I should be good to go.

jeff@sa · #6 23-12-2011, 08:05 AM

Hi Dan,
Great shots.
I have 2 400D's. One of them is Modded for deepsky shots but I find that shooting past ISO800, even with the noise reduction on, gives too much noise.
It is also better to drop you F-ratio a couple of stops to keep the images sharper. You may find it easier autofocussing during daylight and fixing the focus ring with tape and switching off the auto focus.
These are just a few things that I have tried.
PM me if you want to discuss further.
Cheers,
Jeff

swannies1983 (Dan) · #7 23-12-2011, 08:16 AM

I was just about to comment on your pic. Focus has been killing me so far, but today's effort was better. I agree re noise. I might drop it back to 800 and up the exposure to 60secs. I see that's what you did with yours. However, I see you have left it at f3.5. Is that with a standard lens?

I have two lens. One the standard lens that came with canon. I also have a lens that came with a film slr camera that also works with my canon. I might set one up for widefield and the other for a bit of zoom. Definitely needs some tape. Is that what you did for the comet shots?

jeff@sa · #8 23-12-2011, 08:27 AM

Hi Dan,
No, this time I sacrificed the sharpness of stars for better detail in the comet.
The shot at f4 was just a bit too dark and as I was guiding on an EQ mount and had foreground detail I didn't want to blur that too much.
As for focus, this morning I was lucky to have a bright light in the distance which I spot-autofocused on before switching off the AF.
Cheers

lepton3 (Ivan) · #9 23-12-2011, 10:24 AM

Nice shots Dan. I had the same issues with the low cloud bank.

-Ivan

swannies1983 (Dan) · #10 23-12-2011, 10:29 AM

Quote:

Originally Posted by jeff@sa

Hi Dan,
No, this time I sacrificed the sharpness of stars for better detail in the comet.
The shot at f4 was just a bit too dark and as I was guiding on an EQ mount and had foreground detail I didn't want to blur that too much.
As for focus, this morning I was lucky to have a bright light in the distance which I spot-autofocused on before switching off the AF.
Cheers

I also have an EQ6 but I can't be bothered dragging that out with me. I will try bumping up to f4-5, reduce ISO down to 800 and increase exposure to 45-60secs. I gather I will get some star trails but it's the best I can do without tracking.

swannies1983 (Dan) · #11 23-12-2011, 10:30 AM

Quote:

Originally Posted by lepton3

Nice shots Dan. I had the same issues with the low cloud bank.

-Ivan

So annoying wasn't it. It was such a narrow cloud band but couldn't have happened at a worse time. Now look at the day. Not a cloud in sight.