Posts tagged “stars

An Astro-photo plan comes together for once!

Plan last night was to head down to Marine Drive in Edinburgh which is right on the coastline next to Cramond where there was a chance of photographing the moon rising over the water. Using The Photographers Ephemeris on the Mac it was possible to see where the moon would rise and there was nothing but water in-between last night. Better still, it was a fairly clear night so off I trotted.

Marine Drive is a funny place. Actually pretty dark, has great views over to Fife and is a prime spot to look for aurora, the only downside is that is seems to be a popular dogging spot which means you get random cars drive up, park, check what you’re up to and head off back up to the dark part of the road!

If you can put up with that though it’s a prime photo spot with a few possible shots, doggers not included.

When I got there the eastern horizon was so dark you really couldn’t tell if there was any cloud there or not but with 10 minutes to go before the moon came up I used the view west for a few shots. Over an hour after sunrise there was a fantastic colour in the sky on the western horizon, too good to miss in fact when you also take into account the slowly receding high tide catching the last of the golden light.

These shots were the result, no filters, just a bit of PP work and that’s about it. The 2nd shot looks closer in towards the Cramond Island causeway.

Cramond Sunset 5 Sept 2012

Sunset over Cramond Causeway 5 Sept 2012

By this point though, it was clear there was cloud on the horizon as the moon hadn’t appeared but there was some hope, a very faint orange glow so worth hanging about for.

In the meantime I took a few shots of the planes on final approach to Edinburgh Airport. This is right under the main flight path and in the dark you can get some pretty dramatic trails.

2 things stood out on the sky at this point, the bright red star Arcturus to the west and the constellation of Cassiopeia, that distinctive W shape. After watching a few landings I got the compositions right and this was the result. 1st shot is past Arcturus and 2nd is past Cassiopeia.

Plane passes Arcturus

Plane passes Cassiopeia

Finally though the moon had started to show, that faint orange glow was now very obvious so on went the bigger lens, after some playing about I got the shots I was after. This might be better with a thinner crescent moon, as the exposures might be closer, as it was I had to really overexpose the moon to get any detail in the foreground.

Moonrise over the Forth 5 Sept 2012

Moonrise over the Forth 5 September 2012

Just a wee bonus, I was back in the car heading for home to get the telescope out when I spotted a plane heading right for the moon, a chance to get that elusive plane in front of the moon shot. With everything packed away I had about 20s to get the tripod out, extended and the D7000 adjusted and on top. No time for the remote so I had to press the shutter button and hope. This was the result, really not clear but I’ll get it next time now I know roughly where and when I can get it from.

Plane in front of the moon

All in, a good night for the 40 minutes or so I was there, much better than the dreadful night had with the telescope later but that’s a story for another day…


Easy time-lapse movies from still images

I stumbled across this earlier totally by accident but I can see it becoming a little obsession for a while.

While shooting the fireworks one camera had a really cheap remote control on it, the sort where you can push the button up and if you have the camera set to high speed drive it’ll just keep taking pics until you run out of memory space. This meant I just engaged that camera to run and I manually triggered the other one. The upshot was, I had long sequences of shots, one after the other which when flicked through in iPhoto sort of looked like a little movie…

An energy saving lightbulb lit up gradually over my head and I ended up going through all the pics taken on Sunday night with the D90 and found quite a few multi shot sequences.

These were all in RAW so I had a hell of a lot of processing to do, the trick being to take each sequence and process every shot in exactly the same way, I done this by saving the settings in ACR and applying to every shot in the sequence.

Next up with all the shots processed was to order them, as I saved with the default name I just ordered by name.

Now, using iMovie on a Mac you simply have to drag all the files in one go into iMovie. From here, highlight all the pics and set the time interval to 0.1 or 0.2s in the clip adjustment menu (little blue drop down in the bottom the highlighted pic. Now pick the Cropping, Ken Burns and Rotation menu, whatever Ken Burns is it’s a pain. Switch all the shots to Fit and click done. This will stop that stupid zoom in thing on every shot from happening. You might also have to go into File — Project Properties and change the Initial Photo Placement drop down to Fit in Frame.

With this done you can now preview the movie and make any further adjustments. Now go to Share — Export Movie and pic the best option for you. I picked the 1080p HD option but beware, 167 12mp frames ended up as a 70+mb .mov file. The .mov is fine for upload to You Tube, Facebook and Flickr so I would assume it’ll upload to other video services too.

And that’s about all there is to it, I’ve also now applied this to sequence of shots meant for a star trail that shows the movement of the stars once you give it the time lapse treatment.

You can check out the final movies on You Tube:

Astro-photography success at last?

Who’d have thought that within a week of buying a new telescope I’d have had 3 clear nights to try it out? It’s almost unheard of, especially in Scotland this year but not being one to miss a decent chance out came the new Celestron NexStar 5SE.

First impressions of this little scope are it’s incredibly well built. Everything about it is solid and the tripod it comes on isn’t a million miles away from the EQ5 I had previously, it’s even got a basic built in wedge. The Alt-Az mount is very different however and must be powered up to use, once you get used to it though it’s pretty easy to use and the GOTO is pretty accurate as long as you take time to align it properly.

First night out I made a schoolboy error and didn’t use a dew shield, the result was a dewed up scope once I had it aligned and ready to take a pic or 2. A roll of thin camping mat and some Velcro has done wonders to address that particular issue!

2nd night out was more about getting a decent alignment and trying to get at least one usable shot. Aligning the scope is easy enough. I’ve not managed to get the SkyAlign 3 star method to work yet but the Auto-2 star works fine and if I sync with another 3rd star it seems pretty accurate, in as much as I can see objects in the field of view if not dead in the centre of the 25mm supplied eyepiece.

One thing I have noticed is that placing the wedge hinge (even if you are not using it) facing north and making the mount totally level really pays off and it worth taking time to setup properly.

Using Artucus and Altair as the alignment stars and then syncing with Vega seems to work fine and since these 3 are visible in the twilight it lets me get setup for the fainter objects in good time.

From the first attempts at photography the real pain I discovered was finding the focus point with the camera. It’s a fair bit away from the focus point with the 25mm eyepiece and unless there’s a really bright star in the field of view you won’t be able to focus through the viewfinder. The solution is to use a really bright star and focus with the eyepiece. Switching to the camera you can note which direction to focus and how many turns it takes to get there with the camera. For the 5se, around 1 full turn right is the starting point and from there you can fine tune.

First target of night 3 was the Double Cluster, Caldwell 14 in Perseus. This looks great in the eyepiece and the stars are nice and bright so it was a good first target. Alignment was reasonable and I was able to stretch exposures to about 8s with no star trailing. The end result showed a lot of stars and some nice colours in the stars too. I’ve not attempted stacking yet so these are all single shots in RAW and processed in Photoshop.

Double Cluster, Caldwell 14 8 August 2012

Next target was the Great Globular Cluster in Hercules, or M13. In the eyepiece M13 is just a grey fuzzy patch and there’s not a lot of bright stars around it so I had to go with the one turn right method of focus and fine tune from there. It took a good few goes but I got a reasonable result, which I’m pretty happy with for a first attempt.

M13 Hercules Cluster 8 August 2012

The next target I tried was the Ring Nebula. This was visible in the viewfinder using averted vision but very faint. As it was nearly straight up though there wasn’t enough room to fit the camera on the scope with the mount base being in the way so that’ll have to wait for another night when it’s better placed.

Next target was the Andromeda Galaxy. I was biting off more than I could chew here and the result shows. We’ll try that one again in the winter nights!

Andromeda Galaxy

I ended the night up on the Moon as it rose about the houses around midnight and considering it was behind thin cloud the result was pretty good.

Moon 9 August 2012

All in though, a pretty good night and I made more progress with the NexStar 5se in 2 nights than I made with the 200P/EQ5 in 4 months which has to be good. As an aside I should also point out that this is what a rank beginner can achieve with a modest investment in a light polluted area.

If that’s not enough to spur you into giving it a go, while out last night on what was a warm and still night I also caught sight of the International Space Station twice and at least 8 meteors from the Perisids which peak this weekend.

Space quite simply, is awesome!

Stars, Planets, Snow, Hail and Wind!

One thing about Astro-photography, you’re totally at the mercy of the weather. No matter what’s going on in the night sky, you can only see it if the clouds let you see it. There’s nothing you can do about it other than cross your fingers and hope that as darkness falls the skies clear. Which predictably they don’t 9 times out of 10. The conjunction of Venus and Jupiter last month being a perfect example. The night the 2 planets were at their closest in the sky thick cloud hung about all night over Edinburgh spoiling the celestial display.

With the weather rollercoaster central Scotland was experiencing yesterday I held out little hope of even seeing, let along photographing 2 meetings of night sky objects last night. All afternoon the weather swung from heavy snow/hail showers to broken cloud and back again. As the twilight approached this was still the case so getting anything was going to take timing and a hefty dose of luck.

With this in mind, I set up the camera and tripod in the garden shed. This is the kit I’ve been using until I finally get my telescope. It’s a Nikon D7000, fitted with a Sigma 70-200mm f2.8 EX HSM and 2x tele converter which gives me a 400 f5.6 lens, 600mm on the Nikon crop sensor. The D7000 is fitted with a Hahnel Giga T Pro remote receiver so I can use the powerful IR remote to trigger the camera. Exposure delay mode is on the try and minimise any shake. At 400mm the slightest movement will be obvious, more so when the subject is many thousands of light years away.

The first object to try for was the conjunction of the planet Venus and the Pleiades open star cluster, also known as M45 or the Seven Sisters. Venus has been steadily getting closer this month and on April 3rd it was sat right on the edge of the cluster to our view. 400mm fills the frame nicely and even though M45 wasn’t visible in the twilight sky, the camera could see it. There was just the small issue of the passing torrential hail shower to wait out first. As the dirty ominous clouds passed I got my first few shots at the target which was made difficult with a biting strong wind. 18″ long lens setups and strong winds don’t go too well together.

So, high ISO of 1600 and 1s exposure to try and keep the stars as dots rather than oblongs and the full 400mm was the order of the day. The wind affected a lot of shots but this was the pick of the bunch. Venus is of course very bright and the star cluster much dimmer, so I exposed for the stars and let Venus appear as an attractive starburst. Exposing for Venus would leave the stars not visible at all.

Venus Pleiades M45 3 April 2012

This shot was taken later on in the night with a darker sky and the 2x teleconverter removed to try and combat some of the “wind wobble”. ISO1600, 200mm and f5.6, 0.8s exposure time.

Venus Pleiades M45 April 3 2012 2

The 2nd object of the night was the close proximity of the Moon to Mars and the star Regulus forming a celestial triangle in the constellation of Leo. The clouds hadn’t parted at all over this part of the sky and it took a while to get any hope of photographing it. With the 2x tele removed due to the distance between the objects around 9.45pm the clouds moved and I got my first shot at the Moon. The final shot had to be a blend of 2 shots, one for the Moon and one for the planet and star. To expose for the very bright Moon left Mars and Regulus nearly invisible, to expose for Mars and Regulus burned out the moon totally and worse still caused huge lens flares.

Moon Mars Regulus in Leo

As the clouds rolled over again the final shot of the night was a closer shot of the moon with the clouds looking all atmospheric. ISO800 at 400mm, f5.6 and 1/25th exposure time done the damage. It’s hard to get decent focus with clouds moving over the moon so I consider this a fairly lucky shot.

Cloudy Moon 3 April 2012

An enjoyable, if cold, night but hammers home the need for a telescope again, even just for tracking purposes it would be invaluable. I’ve pretty much decided on a Skywatcher Explorer 150p Newtonian on an EQ3-2 mount which I’ll fit with the optional motor drives. Hopefully I’ll have it soon when the real fun and steep learning curve will start.

Photographing the International Space Station (ISS) from the UK

Valentines Day this year saw the start of another series of visible passes from the UK of the International Space Station, which if timed correctly can provide a nice photo opportunity. Lot’s of satellites are routinely visible from Earth but with sheer size of the ISS makes it a worthwhile subject to hunt down.

When it’s visible essentially what you will see if a very bright dot in the sky moving at a fair pace. You won’t confuse it with aircraft as it doesn’t have any flashing lights, it’s a steady white light similar to a bright star moving across the sky. For it to be visible though you need to catch it when it’s not in the Earth’s shadow as the light is provided by the sun reflecting off its surfaces, if it’s out of reach of the sun, you won’t see it.

Predicting where it will pass is pretty easy if you have access to app’s such as Star Walk on the iPhone, or any similar night sky tracker that show’s satellite positions. With Star Walk you can locate the ISS and then fast forward time to see where it will be at any given time, what it won’t show you though is if it will be visible from your location or not.

To determine visibility you’ll need the Heavens Above website. Simply select your location in the configuration settings and then look at the ISS predictions for the next 10 days, this will show you all the visible passes. Remember to deduct 1hr from the time for current UK time. Also check how long it will be visible for, it might be only a handful of seconds, it might be minutes depending on the position of the Earth shadow. The lower the mag value, the brighter the pass will be.

Armed with this information, what you need now is a nice dark location with a good view to the West and South and a clear sky, the ISS will arrive from the West travelling east. On a shorter visible pass your best bet is to setup the camera looking approx South-West, if you have access to the Star Walk app, try to see which easily identifiable star constellation it will pass near, that will help you decide where to point the camera. At the moment, it’s passing very close to Orion, one of the easier constellations to find.

Usual star photography settings apply, you want to be (in a very dark location) around ISO1600, lens as wide as you can get it (f3.5-4.5 is fine) and exposure should be enough so the sky looks light but not blown out, you can darken the sky back down again in post processing but for now we want to be sure we’re picking up as much image data on the stars as we can. In more light polluted area’s you’ll have to drop the ISO to maybe around ISO400 to stop the image blowing out.

After that it’s a case of watch and wait. Take a few test exposures so you know what field of view you’re going to capture in the shot, as you see the ISS (it’ll be fairly obvious) approach your field of view, hit the shutter (with a remote obviously) and keep taking exposures until it’s gone or you’re sure it’s out your field of view.

You can always combine multiple exposures in a programme such as Startrails.exe or StarStax to get a full trail of the ISS over the frame later.

This is an example of pointing the camera to much to the South and not enough to the South West, the little streak on the bottom right is the ISS but despite having watched it for a good 20s before it went into the shot it then went into the Earth shadow and that was it, gone for the night! There are loads of opportunities though over the next few days so if you don’t get it first time, try, try and try again!

ISS over the Pentlands

If you get a dark enough location you might also be lucky enough to get some decent star shots in general just now, with the moon well out the way of the early evening night sky the stars are nice and bright to the point it’s even possible to pick out (faintly) the Milky Way just a few miles outside light polluted Edinburgh.

Stars over Harlaw

Star trails revisited, 10 easy steps to better star trails pictures

It’s been a learning curve the star trails shots. What I’ve noticed is that I’m pulling more stars out the shots now than when I first started and this is turn leads to denser trails. So what’s the difference and how do you get more stars?

1. You MUST shoot in RAW.

2. Compose your shot and expose to the point that you can see a lot of stars in the preview but don’t totally blow out anything else you might have in the shot. In light polluted areas I’ve been using 30s at around f7.1 and ISO400, in darker areas I can drop to around f3.5 quite happily.

3. Take at least 20 shots, the more the longer the trails. Focal length plays a big part here. At 18mm 20 shots will give a short trail, at 50mm it’ll be a longer trail. a cheap 50mm f1.8 is the perfect lens, but if you need wider try and get more frames.

4. What I do now, is to take all the RAW images and dump them into a folder. Now with Adobe Camera Raw (this will transfer to Lightroom too), open the first 10 RAW files. Select the first file and hike the clarity up to 100%.

5. Now drop the exposure slider to the right until you are bringing out stars, bumping up the fill light also helps.

6. Now swith to the Tone Curve tab, at the bottom of the box are 4 sliders, you want the light and darks sliders, make the lights lighter and darks darker until you get a balance of the stars with a darker sky. You will also need to go back to the basic settings and fine tune Temperature and Hue.

7. Once you have a nice balance save the settings and these will now appear in the Presets menu under the name you saved it as.

8. Now select all the images you opened and apply this preset to the all and click Open Images.

9. Once all images are open simply save each jpg and close the shot, repeat for all the RAW files you have.

10. Combine the processed JPG images in your chosen programme for blending, usually StarStax or StarTrails.exe and save the final image.

Once you have that final image you can fine tune with a little colour balance if needed. A bit of dodge and burn can go a long way to to lightening and darkening areas a little at a time until you get the shot you’re happy with. Once that’s done, save and admire!

Both these shots were processed in the way above, both are only around 30 exposures (which if it’s under 0c outside is more than enough!), but the first shot was as 18mm, the 2nd shot at 50mm where you can see a big difference with regards to the trails.

18mm shot:
Newhaven Star Trails

50mm shot:
Telegraph Star Trails

by way of a comparison, this was the first star trails shots I took, you can see the difference in the amount of stars I’m managing to extract now with different processing.
Forth Bridge Star Trail - Explored

The easy guide to photographing star trails

So, star trails. Striking images certainly but surprisingly easy to do with the right software.

First things first, to make your life a million times easier, if you’re using a Mac, download StarStax and on a PC, Startrails.exe, Google them, easy to find and both a free download. This is the software that will combine your final set of images into the star trails shot. If you really enjoy spending ages with Photoshop you can blend each image separately but these make life a lot easier.

Other than that all you need is a camera capable of doing 30s exposures, a tripod, remote control and a nice dark area where you can see plenty of stars. Don’t underestimate the power of light pollution to ruin a shot, the example below was taken in my garden in a built up area of Edinburgh, the light pollution is easy to see so try and get out of town somewhere.

The effects of light pollution

With everything in place you now need to locate Polaris. It’s not essential but if you can keep Polaris in the image then the stars will nicely rotate around it. To find it look for the Plough, one of the more well known star clusters. It’s in the shape of a soup ladle (roughly) so follow the handle around to the scoop and locate the last 2 stars in the Plough. From there in a straight line around 3 times as far away as the 2 stars are from each other will be a slightly duller star, this is Polaris. Or even easier, get one of the smartphone apps such as Star Walk on the iPhone and use that to locate Polaris.

With this done compose your image. You want a 30s exposure that doesn’t overexpose any foreground interest but shows up a lot of stars in the preview image. Usually you’ll be around f7.1 or wider and ISO400 or above to get what you want. The more stars you see on the preview, the more trails you’ll get in the final image. Shoot in RAW mode too if possible. I’ve also found that the wider the lens the better. You’ll want to be on manual focus, and with focus set to infinity.

Once you’re happy with the shot it’s time to settle in for the long haul. You’ll need at least 40 shots to get a decent trail in your final image. The more the better but you’ll be there longer to get them. A decent compromise is around 60 shots if you are picking up a lot of stars. You’ll either need to fire the shutter every 30s or if you have a programmable remote set it to 30s exposure with 32s delay to give the camera time to process each image.

With your shots in the bag, it’s time to thaw out and start the process magic.

First thing to do is to process the first RAW image, how you do it is personal preference but make sure that you get a decent mix of stars in the sky, the sky kept darker and don’t blow out any foreground. Once you have a image you’re happy with, save the settings and then process every image with the same settings. It doesn’t take that long to do with ACR or Lightroom, and save each as a jpg.

Now, open all the jpg’s in your processing software, either StarStax or Startrails.exe and start it off processing them using blend lighter to combine the images. After less than a minute you’ll have the stacked image. If you find cloud has passed through the shot you can exclude these images and start again but remember you’ll get breaks in your trails. Best plan in this case is to try and blend again missing the offending frames and see if it’s any better, sometimes the cloud doesn’t matter that much.

Save the final image and open it in Photoshop or similar. From here you can do your final adjustments, usually darkening the sky, upping contrast and that it, and this is what you should get…

FRB Star Trails 29 Dec

This panoramic shot was slightly different to do. Had I shot this with the bridges at the bottom of the shot the verticals of the bridges would have been hugely distorted, to get around this I shot a single long exposure image with the bridges in the middle of the frame where the distortion isn’t an issue. I then moved the camera to where I wanted the bridges in the final shot and shot the multiple star images. I finally took the long exposure image, moved the bridges to the bottom of the shot and extended the sky with content aware fill, I then blended in the star trails image and selectively erased the bridges until I had the correct verticals version overlaid with the star trails. A bit more mucking about but a much more pleasing final image.

Forth Bridges Pano Star Trails

So, a final checklist…

Warm clothes if doing this in winter, a simple MUST have.
Sturdy tripod
Camera capable of 30s exposures
As wide a lens as possible
StarStax or Startrails.exe software
Remote control for camera
A clear night
A dark(ish) location

That’s it. Off you go and shoot those stars!