Let's Talk About ~ Astrophotography!

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I am going camping next weekend and since I doubt I will be able to sleep much during the night (I work night shifts mostly) I thought it might be a good idea to try and learn a little bit about Astrophotography before I go, so I can have a good go at it while I'm there.

I am interested in trying some Landscape shots with foreground interest and the gorgeous star trailed skies you see now and then. I want to get it right, so am open to advice from those who know a thing or two about doing it successfully. This is my first longish holiday in 5 years so I don't want to waste a moment. It's probably also going to be the only chance I have of being away from light pollution for a while to.

I'd also like to have a bash at photographing the milky way, tip on this would also be great.

I will have my laptop with me to do my editing, so are there some neat little bits of free software out there that will help me achieve this kind of stuff? I want to be able to check I have got it right before we come home, as I won't have another opportunity for a long while.

I'm also hoping this won't all go down the pan with bad weather :lol: So please, no more rain dances folks!

The kit I have available to me includes:

Canon 40D
Canon 400mm L f/5.6
Canon 18-55mm Kit lens
Remote switch
Redsnapper tripod and 3 way head :D


Jo
xx
 
This weekend is a waxing gibbous moon and next weekend it will be a waining gibbous (both almost full). When the moon is up it is very challenging to do star trail images. Its possible, but it requires more technical skill and the results just wont be as good. You will be able to see the very brightest stars, but seeing the milky way will be absolutely impossible. (even if you did want to do this you woold be pushing the limit of your gear)

Given that the moon is essentially full you dont have much time between sunset and sunrise so there is no way you are going to get the balcck skes of a new moon or when the moon is below the horizon.

However, if you cant sleep you really can take excellent images in moonlight. http://www.davidclapp.co.uk/image_gallery.php?image_subcat=Moonlight - All. Another strategy would be to try to sleep from 10ish to 4.30 and get up for sunrise.

Best of luck and enjoy your camping.

Alex
 
Oh crap I totally forgot that moonlight and star trails don't work together! I'm planning on some moon shots to, why didn't I remember that? :bang:

Will this definitely not work even if pointing the camera at the opposite side of the sky to the moon?
 
well when the moon is just rising/setting and you pointed in the opposite direction and you have a clear night (unlikely given the forecast) then you will be able to shoot the brightest stars. Because of the long exposure nature of star trail photogrpahy the moons light will very quickly make the sky a bright blue, long before you have trails of reasonable length. To get round this you can take hundreds of shorter (say 30 second) exposures and stack them together in photoshop to create the trails, using the lighten blend mode to ensure the brightness of the sky does not increase. This is a time consuming process, both the capture and processing requires some technical skill and I would say it is beyond the capabilities of most of the people who have not tried it in favourable conditions. For that reason I would say it isnt even worth trying. Besides even the tiniest bit of cloud would absolutely ruin such a shot.

Alex
 
To get startrails:

Set you camera on the tripod, on the strap there should be a little rubber thing that says 'canon', put this over the viewfinder (take off the viewfinder surround first). Zoom out to the widest angle, and manually focus on infinity (this may be hard to do with the kit lens, as infinity isn't always the focus ring turned entirely).

In manual mode, set the camera to a 30sec exposure, widest aperture, iso~400-800. Tungsten white balance, and i would suggest Medium image size (large/raw will be take longer to process)

Look for where the 'big dipper' is. from the farthest star right of the big dipper, trace up to the polaris star:
Polaris-found.jpg


This star will remain still while the other stars rotate around it.

Set the camera to continuous shooting and have the cable release held on. You should end up with MANY MANY pictures. I prefer stacking them, as a 15min + long exposure will give you tons of hot pixels.

http://www.startrails.de/html/software.html <use this software to stack the images. great program.

That's MY technique anyway, I'm sure others can offer different advise. Just go with what works for you. Good luck getting a clear night though, the weather's been awful!

[EDIT] Without a really wide aperture lens and/or an equatorial mount, chances of getting the milky way are low. There is also a lot of light pollution in this small country, even though it is hard to see when you're out in the countryside.
 
alexnail said:
well when the moon is just rising/setting and you pointed in the opposite direction and you have a clear night (unlikely given the forecast) then you will be able to shoot the brightest stars. Because of the long exposure nature of star trail photogrpahy the moons light will very quickly make the sky a bright blue, long before you have trails of reasonable length. To get round this you can take hundreds of shorter (say 30 second) exposures and stack them together in photoshop to create the trails, using the lighten blend mode to ensure the brightness of the sky does not increase. This is a time consuming process, both the capture and processing requires some technical skill and I would say it is beyond the capabilities of most of the people who have not tried it in favourable conditions. For that reason I would say it isnt even worth trying. Besides even the tiniest bit of cloud would absolutely ruin such a shot.

Alex
Click to expand...

Whilst you have some very valid points, I do believe everything is worth trying at least twice :) Thanks though, some sound advice there :)

Paleblue ~ Thank you! That's a very simple explanation, and I hope to be able to produce something. If the weather is too bad (cloudy skies) for this kind of thing, then I will just have to try some long exposure shots of other things to keep me occupied instead. Win win :D
 
what paleblue says is the way to go.
remote locked, 20-30 second exposures depending on ambient light,sit back and wait for 2 hours. when you think you have enough, don't alter anything on the camera at all and take 20 shots with the lens cap on. this gives you some blacks for the startrails program to use for fixing hot pixels,
using 20-30 secs will get rid of most moon pollution. turn up the iso the highest and use that to test you have the focus point then wind it back down, turn off the long exposure noise reduction. ermm:thinking: hang a weight on the tripod, sometimes i put a bean bag on top of the camera as well,if the wind is up. errm:thinking:find a good foreground item for interest, you will kick yourself if you choose a poor one and waste 2 hours.
 
As for general starfield shots... i.e. the milky way... ignoring the fact the moon will wash everything out... have a look at http://www.talkphotography.co.uk/forums/showthread.php?p=1184389#post1184389. I used this technique the other night, both with an experiment with the nifty... needs some work (although I can now use my LP filter with it, and I'm working on mounting it on my tracking mount :D)... and to capture a panoramic of the milky way with the kit lens. Neither are particularly good, but I can post them if you want, more experiments to see how tough it was going to be, I didn't even bother with darks or flats to reduce noise and dirt.
 
(Kinda on topic)
If you have an iPhone, may I suggest getting an app called 'Planets'. It gives you rising and setting times for the sun, moon and all the planets. Also gives dates for full/new moons etc. It might come in handy :)
 
Comfy said:
(Kinda on topic)
If you have an iPhone, may I suggest getting an app called 'Planets'. It gives you rising and setting times for the sun, moon and all the planets. Also gives dates for full/new moons etc. It might come in handy :)
Click to expand...

Thats a great little app, I'm sure it will come in handy, thanks :thumbs:
 
Some great advice folks, thank you :thumbs:
Comfy ~ I don't have an iPhone, I don't even have a camera phone :lol: But thank you ;)
 
Jo, it works just as well on an ipod touch if you have one of those. I also use Moon Atlas, and Star Walk apps on mine. Star Walk has been the most use so far... It helped me a lot locate the Whirlpool galaxy (you do need a scope for this though), it's also got the option of red screen to protect your night vision, which is all well and good, but if the ipod goes to sleep, it comes up in full bright mode till you get back to the app.
 
I almost completely disagree with alexnail, sorry. While bright moonlight can destroy your chances of taking a photo of th milky way, for startrails it is makes them far better. If you don't have a moon you will find it very difficult to get an exposure of the foreground, with a moon and using multiple exposures (with startrails.de) you can get a beautiful well lit foreground and a beautiful set of startrails. The benefit of using multiple exposures is also that you don't have to worry as much about the battery running out, condensation or knocking you camera accidently, as you can just use the program to stitch up to the point it went wrong.

One thing as you mentioned already, is that you really need the moon behind you somewhere, so it lights up your foreground interest (it can also be to the side if you want shadows).

Technique and kit wise you will want to use your kit lens, focus it on the moon and then put it in manual focus (maybe tape it down to stop you knocking the focus out) so you have infinity focus. Make sure you have Long Exposure Noise Reduction off!!! (it will only be on if you changed the custom function). If you have it on you can throw away your photos as the star trials will look like morse code, and not trails. Once you have done that set the camera up (maybe with the north star in a corner so you get some rotation around a point?) and set the exposure..

Exposure wise you will want ISO 200, a high f/stop (say f/4 or even wide open, you want as much light as possible) and then set your exposure length. Exposure length is what you will use to change the exposure of the scene, I suggest around 2 minutes for a full moon, but vary it depending on the exposure of the sky and foreground (it won't affect the brightness of the stars or the number of stars, that is affected by the aperture and ISO). I would suggest trying to get the longest exposures you can as you will end up with less frames taken, meaning less space and more importantly less gaps in the trails (you will have a tiny gap between each frame as the stars move during exposures).

Once you have set the exposure (as mentioned before, you can use the high ISO trick for this, as well as for checking focus and framing) set your remote timer (if you have one, if not I recommend getting one off the bay for around £20) to the exposure length you want and the number of exposures you want (til the battery runs out?) and set it off. If you don't have a remote timer you will need to use your remote switch to take another exposure, and probably stop the exposure as well. If you do it this way make sure you click the button as fast as possible, so the time between exposures is as small as possible. TBH I don't take any dark frames any more, I don't find I need them, as you will usually have to clone out aircraft trails anyway, so hot pixels can be cloned out at the same time.

For foreground interest you want something bold and prominent in the sky, with not too much detail (ie something with a prominent outline), you will get some detail in shot if exposed right, but it's more about the shape than detail. The most widely done are things like Tors (or other rock outcrops), old building (churches, castles) and standing stones (eg stone henge) for this very reason. You can also try taking photos of your tents (which will glow if you are inside them with a light on) or even a bonfire.

One thing you do need to watch out for is cloud, it can ruin a shot (making massive gaps in the trails for one), however if well behaved it can be used well in the shot too. Also you could try some trails just before sunrise, or after sunset too, when there is still light in the sky.:)

Some examples of all this from my work are:

Startrails+final.jpg


Sheeps Tor
Full moon (to my right) with the 18-55 kit lens on a 400D, around 30 exposures (manually done!) at around 2 minutes (ISO100 and wide open)

Campfire-rotatedandlenscorrect.jpg

Death Valley

Yes, it was shot in one of the most remote place on earth, however there is a large fire letting out lots of light, but also making an interesting focal point. 8 exposures of 6 minutes at ISO200, f/4.

Who says Startrails can't be done in towns and cities!

Startrails+finished+copyll.jpg

Smeatons Tower
The Lighthouse was moved from offshore to the Hoe in Plymouth. Behind and to the sides of me are the streetlights of Plymouth. ISO100 I think, wide open and around 30 exposures of 30 seconds a piece.

Good luck with trying, they can become horribly addictive, which is a pain, as you invariably have to end up in the middle of nowhere, on your own, in the cold, sat in the dark for hours on end... :p

EDIT: One last thing, make sure you shoot RAW, White balance can be a right pain to get right, especially in more built up areas. Either set a custom white balance or do it with the RAWs. As for processing the best bet is to open the first RAW, do the processing you want to it, save the photo AND the settings, and then paste the settings onto the other RAWs, saving them as TIFFs. Stick those TIFFs into startrails and output to TIFF the finished photo, then import it back into your image editor for the final touches (which can include taking the foreground from a single frame and pasting it in front of the foreground of the star trail (the connecing of the trails can sometimes cause the foreground to become blurred, and at any rate you will want to seperate the foreground from the sky to process them seperately).
 
:eek: Amp, thank you sooooo much for taking the time to type that all up for me. It's easy to read and ... well, I now feel confident :D I can do this :woot:

I am thinking of trying this out with Whitby Abbey as the foreground interest. Or I may go down onto the beach and get the piers in, or something else, we shall see.

I'm going to save your post as a text document, as I won't have internet out there (:eek: I'm going 5 days without internet *gulp*), and I don't currently have a working printer. I want to make sure I can read it over again if I need to. I hope this is OK with you?

Again, thank you so much :D :clap:
 
A very good post AMP34 and some very good advice (great shots too) :thumbs: Just to add to it....... No don't need to, just seen the edit :lol:
 
Thanks, it was no bother, as you may have guessed, it's a bit of a passion of mine :lol::) .This thread has also reminded me I need to get round to writing a tutorial on this for my website, if I do i'll stick a link to it here so you can read that if you want too Jo :)

It's pretty easy so confidence is the key, and the other key is the foreground, which you look like you have sussed already, an Abbey/Church like is Whitby is a shot I have been wanting to do for ages. :thumbs:

Look forward to seeing your shots. :)
 
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