Need some advice & guidance about night/astrophotography

[SJ]

Last night im trying to capture milky way, but i dont see any milky way at the sky, but at least i got one photo to share. This is my 1st attempt to capture night skies , hopefully u all can give me some advice & guidance about night skies/astrophotography & how to find the milky way

This picture taken with 5DMIII + 24-70II, iso 800, f/4, 30 sec, manual focus.

TQ

 

[noisejammer]

Finding the Milky Way
I suppose the easiest way is to download a copy of Cartes du Ciel, or if you're willing to spend a couple of bucks, an app for your smartphone or tablet (assuming you have one.) I use Cartes to plan observing sessions and "The Night Sky" by iCandi on my mobile devices. Cartes is completely free and can be had from http://www.ap-i.net/skychart/start .

On photographing the Milky Way,
1. You really want to get to the darkest site you can find. The light from the MW is very faint and if there is any light polution, it will be overpowered. So... look for a place far from the maddening crowds.

2. Choose a clear, moonless night - the moon can wash out the MW too.

3. Try wind the ISO up to 1200 or 2400 - on a 5D2, these offer the same noise as 800 and 1600 ISO respectively and you can do some noise filtering later.

4. Use a wide angle lens because it will allow a longer exposure without visible smearing of the stars. This is dependent on the direction you're facing (as well as the pixel size and lens resolution) but a reasonable rule of thumb is 15-30 seconds with a 24 mm lens. If the focal length doubles, the exposure must half. I made the calc for a 5D2 - if the pixels get smaller than 6 microns, the exposure must get shorter too.

5. Select a lens that has no focal plane curvature when it's focused at infinity. Ideally it will be reasonably fast - say f/1.4 or so so that you can stop down to f/2 and improve the image quality and vignetting considerably. A manual focus lens (read Zeiss) is probably your very best bet.

6. Use a very stable tripod, mirror lock up and either a timer or cable release to start the exposure. I usually use sunlight white balance.

7. Turn off autofocus and use magnified live view to focus the image manually. Use a Zacuto 3x loupe if you can afford one. Finally, it's best to focus at about 1/3 to 1/2 of the way from the edge of the field because that tends to get most of the image reasonably sharp.

Ok - it may be bad form but I may as well make a plug for the Canon DSLR Digital Astrophotography group on Yahoo! We have something like 2300 active members. Full disclosure - I'm one of the moderators.

 

[TexPhoto]

You might also consider picking up a cheap film body if you want to capture the light streaks of the stars as they move. Assuming you have a 2nd lens, a film body or 2 can allow you to set-up and shoot multiple photos at the same time. Esspecially handy when some of those photos have 1+ hour wait times.

 

[MintMark]

Another good "sky simulator" is http://www.stellarium.org/... it can show you the constellations and the milky way (and loads of other objects) for any time of night at whatever location you put in, past, present and future.

You'll see that some parts of the milky way are brighter than others (brighter looking to the centre of the galaxy, near sagittarius), so if you can see that it's a good target. To capture a given view you have some flexibility... you can select a time of year and stay up until the right time of night or you can select a time of night and wait for the right time of year... whatever fits your schedule. You might also want it in a particular area of the sky... for example, away from a distant town's light glow, or overhead where's there's less atmosphere in the way. A little planning can help a lot. For me August is milky way time.

Everything that noisejammer said is true... and there's loads of information about on the web.

 

[SJ]

Thank you for sharing information.. im really appreciate it.. u all awesome 8)

 

[Hector1970]

Some great advice above from Noisejammer.
I must check out Cartes Du Ciel. I hadn't heard of that before.
The iPhone Apps are good for finding out what is what in the sky (amazing really - but we are just getting so used to the technology).
My little piece of advice is to check out a Samyang (Rokinon/Wallimax) 14mm F.28 Lens.
It's super on Full Frame for Wide Field Astrophotography.
There isn't a hard infinity stop, infinity is a little before the end of the focus
This is a relatively cheap lens (all manual - which I think actually helps learning - but may cause initial confusion).
I've used their 8mm Fisheye on an APS-C camera as well with good results (this is F3.5).
I shoot at ISO 1600, F2.8 and 30 Secs normally on a 5D Mark III.
The sky helps too.
I was in Australia recently - it was amazing at night time away from civilisation.
It's not so easy at home in Ireland when you can't guarantee what the sky will be like (and will be cloudy most nights)
Here's an example from Australia

http://www.flickr.com/photos/fergalocallaghan/8398523233/#in/photostream

 

[woollybear]

Another thing that Stellarium can be used for...it can show you what the camera will see based on sensor size and focal length. Kind of fun to see what your picture is supposed to look like

 

[Axilrod]

Read the thread about the spiral arm of the Milky Way above this post, there is a lot of good information in there. I didn't read any of the responses to this so some of this may have been covered, but more or less:

•Bump your ISO WAY UP - ISO1600 at least but I'd go ISO3200
•Set your lens wide open or very close
•30 Seconds is too long for a 24mm lens. In order to figure out the maximum exposure time before the stars turn into a pill shape you divide 600 by the focal length (although some say 500/FL to be safe) and that's the max exposure time. So 600/24 = 25, so you were about 5 seconds over on this one. Now 600/14 is 42.85, so if you picked up a Samyang 14mm you could go over 40 seconds no problem.
•Turn off all noise reduction/highlight tone priority
•Cover your viewfinder with tape
•Turn on silent shooting and mirror lockup
•Use a remote trigger or use the 2 second delay

And the absolute most critical part:
Get as far away from light pollution as possible, this makes absolutely all the difference in the world. Look at this map http://www.blue-marble.de/nightlights/2010 and find a really dark spot. Also it looks like you went out when it was a bit cloudy, you want to go when visibility is high.

As for getting the Milky Way, it has to be the right part of the year and it depends on what part of the world you are in. If you are in the Northern Hemisphere the brightest part of the Milky Way is visible during the summer months, and that part is near the constellation Saggita.

Download this app called Stellarium http://www.stellarium.org, which will allow you to put yourself at any spot on the Earth on any given day at any given time and if you hit play it will show you what will move through the sky over any period of time. IMPORTANT: when you launch the app, make sure you turn the atmosphere off (gives you a more clear view) and turn "constellation labels" on and look for Saggitarius. That's where you want to point. There are other parts of the Spiral arms visible here and there, but that is the part that you see in the Milky Way pics that "wow" you the most.

Good luck!

 

[SJ]

Thanks for the information/guide/advice