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wasnapper
09-09-2014, 10:46pm
I would like to have a go at star or milky way photography. I have an f8 mirror lens or 18-55 and 55-250 or 70-300 zooms with widest aperture of 3.5.

What would be the best lens and exposure for this?

wasnapper
10-09-2014, 8:11am
Hmmmm

Granville
10-09-2014, 8:26am
I have no idea, but I do have the same question. Waiting to see what responses this brings.

Allann
10-09-2014, 9:21am
Your 18-55 will prob be best as you'll get more of the sky in. But you want your fastest lens as you iso will be high and your shutter slow. Just do a quick search on here, or check previous posts in the night/astro forum for what others have already posted.

Allann
10-09-2014, 9:22am
Can even check out the learning section for hints.

wasnapper
10-09-2014, 9:33am
Thanks John. I'll have look at the learning section after work [emoji4]

Granville
10-09-2014, 1:46pm
This is what I am struggling with at the moment, and one of the reasons I want to get a fast, wide lens. For Milky Way and Night sky shots I am pretty much stuck with a shutter speed that avoids start trailing. So, 30 seconds or so. In order to gather more light I need a higher ISO, or a wider aperture. The higher ISO has a bit of a small ceiling on a D3100, so the choice comes down to wider aperture on as wide an angle lens as is practical. I have the standard Nikon kit lenses, a 50mm 1.4 (too narrow) and also a Tamron 18-270 3.5 -6.4(?) PZD. I have been thinking about a Tokina 11-14 2.8 but they aren't cheap. I know I would use it for landscape photography as well, but I am naturally slow to make decisions, so it waits for a while.

Having said that, I have taken Milky Way shots at 18mm 3.5, but my PP skills with Lightroom, which I have only just purchased, are not good enough to know whether or not I can enhance what I have with sufficient quality. They might be perfectly acceptable if I learn Lightroom well enough.

wasnapper
10-09-2014, 5:52pm
Granville, Perhaps you could post one of your shots and ask if someone can give you a workflow for lightroom. I don't use it myself

Allann
10-09-2014, 5:53pm
I use a 17mm f4 lens for most of mine, so what you have should be fine. best advice i can give, make some new images, share them here and ask for specific advice.

111594

ISO 3200 17mm f4 30sec

All processing was done in Lightroom so that should give you an idea of what is possible. I don't by any stretch of the imagination call myself good at this sort of image but like you I'm dabbling in this stuff too.

RJD
10-09-2014, 6:30pm
I use a 17-50mm f2.8 Tamron, at the wide end obviously, and I have found that to be a really good lens for that and landscapes, as well as indoors when I can't use a flash.

wasnapper
10-09-2014, 9:32pm
Thanks for the info. I have ordered a fisheye lens but might have a go with the kit lens (when the sky clears lol) pretty poor in Perth just now

Granville
11-09-2014, 2:03pm
Thanks all. I'll see if I get one of my old photos and post it up. Or perhaps I have an excuse now to get out in he bush a bit and take some fresh ones. Must find that fishing rod. Honey! We're going camping. :)

wmphoto
11-09-2014, 7:21pm
I went as low as 8mm at f4.5 (Sigma 8 -16) which isn't particularly sharp at 8mm and wide open. I found my best results were at 17mm f4 (Canon 17-40). As a rough guide for exposure time to avoid star movement, the formula is 500 / (mm * crop factor) = seconds. i.e..

Crop body factor 1.6
Focal length 17mm

So = 500 / (17*1.6) = 18.4 seconds exposure.

I actually ended up going 25secs and still got good results. Shoot wide open and bump up the ISO as high as noise levels let you. I went ISO1600 on my 450D and ISO3200 on my 7D before the noise became too much.

Edit - turn off IS, sturdy tripod and no wind are a must.