Cape Leveque Nightscapes with the Vixen Polarie

[iceman]

It was night 3 of our tour, our 2nd night at Cape Leveque (http://www.mikesalway.com.au/tag/cape-leveque) and I was down on the beach at about 11pm, all alone with nothing but the dark skies and expanse of the Milky Way above me.

I was testing out the Vixen Polarie, and was keen to see how it could be used for nightscape photos (landscape astrophotography) in addition to the straight 'sky' shots, like this Milky Way image (http://www.mikesalway.com.au/2012/08/25/milkyway-galaxy-with-the-vixen-polarie/). The challenge of course, is that in normal nightscape photos we have to keep the exposure short enough so that the stars remain as points and not trails. When using the Vixen Polarie, we've got tracking on so can use longer exposures and the stars still remain as points, but during the tracked exposures, the foreground is also shifting and will become blurry.

The solution then, is to take 2 shots - one with the Polarie tracking on (to keep the stars sharp), and one with tracking off (to keep the foreground sharp). The images can then be combined in Photoshop using standard layer masks.

Depending on your foreground, it may be more difficult to get the layer mask correct, but with these rocks at Cape Leveque, the edges made for easy masking, especially when using a tool like Topaz ReMask.

The first image shows the Emu diving into the Indian Ocean. Both the foreground and sky are single 90 second exposures, with the Canon 5D Mk II, Samyang 14mm f/2.8 lens @ f/2.8, ISO3200.

The red haze near the horizon might be airglow, and was visible on the back of the camera and I certainly noticed 'something' with my eyes but the colour wasn't visible.

In the second shot, the Small Magellanic Cloud (SMC) has just risen above the horizon. Both the foreground and the sky are single 2 minute exposures, one with tracking on and one with tracking off. They were combined in Photoshop.

In the 3rd shot turning around to the North East, the Milky Way wasn't quite as bright but the rocks gave a great foreground scene. In this shot, both the foreground and sky are single 2 minute exposures.

- Large 1 (http://www.mikesalway.com.au/download/287)
- Large 2 (http://www.mikesalway.com.au/download/290)
- Large 3 (http://www.mikesalway.com.au/download/288)
- Blog (http://www.mikesalway.com.au/2012/09/03/cape-leveque-nightscapes-with-the-vixen-polarie/)

Overall, I'm very happy with the performance of the Vixen Polarie. There's very little trailing in the 2 minute sky shots, considering I didn't polar align accurately. It also helped that I was using such a wide focal length.

There's quite a bit of interest in these small, portable 'trackers' now - especially as landscape astrophotography / nightscapes is becoming a much more popular genre of photography. For the price, the Vixen Polarie (at AU$495) is good value, small and portable and can handle the weight of a standard DSLR and lens. Well worth checking out.

Thanks for looking.

[gregbradley]

That's fabulous. I like these a lot. A tad warm in colours perhaps with too much yellow, reds and browns in it.

The Polarie seems very very handy. There doesn't look like there would be much more advantage to doing 5 minutes there. What do you think?

How hard would it be to polar align with Octans being so hard to spot?

Greg.

[multiweb]

That's terrific. The milkyway is so bright. It looks like a raging fire column. Superb colours :thumbsup:

[sheeny]

They're gorgeous Mike.:thumbsup:

I'm still very envious of your trip.

Al.

[h0ughy]

yeah i am sick of the way he keeps posting things weekly to rub our noses in it;):P:lol:. i agree it looks a tad "warm" but with all that milky way sky it could have been the colours surrounding as well from the local landscape? Nice work Mike.:thumbsup:

As for the polar alignment - get the polar scope for this - worth its weight in gold. I used it several times as Astrofest and it made life very good – my 46 minutes worth of shots on crux hardly moved – I never cropped the image. So when you get it right it works well. If I had have trusted it more I could have gone a lot longer in the exposure department – live and learn.

[lacad01]

Outstanding shots Mike. They look like the scene from "Contact" when Jodie Foster is on the beach meeting the alien/dad :)
The more I see shots taken with the aid of a Polarie, the more I want to get one now :P

[StephenM]

Fantastic images Mike! I nearly bought one of these last month, but went for the Tokina 11-16 lens instead... but I think a Polarie is back on the wish list!

Cheers,
Stephen

[ReaPerMan]

Terrifics shots Mike! The polarie is on my must have list. Might have to thin out some of my other gadgets first!

All the best

Paul

[CapturingTheNight]

Nice images Mike :thumbsup: I see many absolutely horrible "composite" images but I like the fact you kept these nice and subtle and I know you did these at the same location and time. Far to often do I see a desaturated daytime shot used and some tracked shot (usually stolen) pasted in the background. For me personally, any image produced using different equipment (in this case, tracking on and off) falls outside of what I consider to be a genuine photograph (but only fractionally) and enters the realm of composites. Please understand that this is just MY thoughts. I personally have never done it and don't have plans to do it anytime in the future. It crosses my personal border. I like the challenge of trying to do images all in the one frame (panos and star trails excluded). I'll copy and paste an extract from an online article I read once about "authentic" photos versus composites. It pretty much mirrors my personal tastes....

"Here is what I think must be true for a photo to be an "authentic" photograph.

1. Photo(s) used in the final image must be taken at the same focal length and using the same equipment.
2. And within the same 24 hour period.
3. With no introduction of or removal of elements except those that are "small distractions". E.g. noise, an overly bright or overly dark element such as shiny trash or a tripod shadow, Or cloning out an object that moved between exposures as in HDR.

I find these acceptable:

-Cropping – any amount.
-Sharpening, or Blurring (smoothing)
-Color correction, saturation or desaturation (but not color change. Green eyes should not become blue ones – though "red eye" correction is certainly ok).
-Selective coloration, including black and white, duo toning, etc.
-Perspective or lens aberration corrections.
-Vignetting
-Framing
-HDR, or bracketed exposure combinations together with tonal compensation.
-Contrast enhancement

For me the following cross the line from Authentic Photographs into Composites

-Use of any elements taken a different focal lengths or with different equipment unless those elements are resized proportionately and placed in their correct and actual location.
-Using elements taken at different dates or from different directions (e.g. combining a photo of lightning with anything that the lighting did not actually strike)
-Moving elements in a single image to other locations (except incidentally to clone out or cover over issues)."


Phew. Sorry for the long post. Again, nice shots mate.
Cheers
Greg

[colinmlegg]

For what it's worth, I tend to agree with Greg. They should be labelled composites. When I did my first trip to the Bungles in 2009 I did similar shots combining longer exposure landscape and shorter exposure skies. The results were pretty spectacular, but I never felt comfortable and never showed them to anyone.

I do see the other side of the argument though. In the future, with improved sensors, we should be able take shots like this in a single frame. You probably won't be able to tell the difference.

[iceman]

Thanks for the feedback guys.

Greg Bradley - I haven't got the polar scope, but after houghy's recommendations I may have to look into it.

I think for a widefield nightscape like this, there's going to be limited benefits to going much longer than 2 minutes. I guess you could reduce the ISO and try and get a less grainy image (than at ISO3200), but I think it's fairly acceptable to have some grain in these type of images. Of course the less the better :)

I'm still trying to get through the images - I'm probably 20% through, that's why there's only 1 image a week coming out - limited time!

Thanks for your thoughts, Greg.

I completely agree about composites that include elements taken on different days, different times, with different equipment etc.

And I agree also with the quoted description of 'acceptable modifications', but I'm also not a complete hard-arse purist about it. As long as it's specified up front and not trying to dupe anyone into believing it's a single exposure.

I'm ok with *this* type of composite, that was taken at the same time, same equipment, same direction - everything the same except one with tracking on/one with tracking off.
Like this one done way back in 2007 (http://www.mikesalway.com.au/2009/02/13/from-the-vault-observing-the-milky-way/), it just wouldn't have been possible without a composite.

Each to their own though. As long as people are honest and upfront about how they made the image, then anything is fair game. It just might cross some people's line about what's 'illustration' or 'art' as opposed to a photograph of a moment caught in time.

There was a nightscape photo that I saw on Facebook a few weeks ago, where the photographer rotated the milkyway to improve the composition, and included elements taken later with light painting etc.
In some of the comments, the rotation of the milky way stepped over the line for some people.

Even this now famous photograph of the perseids (http://www.flickr.com/photos/davidkingham/7769126492/in/photostream), included LOTS of alterations, including one from sunrise to help light up the foreground. It's a brilliant photograph, very well planned and executed with excellent photo editing skills.

Is it a real photograph? To me, it's stunning and I'd have been very pleased to produce it myself.

But everyone has their own 'rules'.

[gregbradley]

What about any deep sky image then? They are all composites and no single exposure would compete.

I guess this is a purist approach but I find Mike's image totally acceptable.

If I do a composite filtered image to create colour and its autoguided is that not an authentic photo?

Otherwise until technology develops much more you would be very limited as to how deep you can go and all will have some star trailing to a greater or lesser degree.

What if the resulting image were all done in camera? (no such routine exists but I am sure some smart programmer would have no trouble coming up with a routine, the D800 already can create a time lapse internally).

Greg.

[iceman]

They are labeled as composites though, Colin?

Were you speaking generally, or specifically?

I'd like to see your Bungles shots ;)

[iceman]

Quite right - timelapse can now be done in camera, and with probably very little extra programming, a star trails image could not be done in camera too (with shorter exposures instead of a long one).

Bracketing and even now HDR composites can be done in-camera.

Where does the line cross when you do it yourself in software, versus the camera doing it?

Interesting discussions..

[colinmlegg]

Yeh, generally Mike. I'll have to hunt them down.

[CapturingTheNight]

As you say Mike it is each to their own. Everyone is going to have their personal boundary. Sorry if I opened a can of worms. I just wanted to voice my opinion on these sort of shots. People often think I use tracking on my nightsky scape work. The real benefit of doing shots in this way is noise control. Instead of 2 minutes at ISO 3200 for each shot, you could do shots for 16 minutes at ISO 400 for exactly the same result but with significantly less noise.
Greg B.- For me, Deep Space images are not composites in the sense I was talking about because you are stacking/adding frames of the same object (just different filters and exposure lengths sometimes). If however someone blended a shot of the Horsehead Nebula with a widefield shot of Eta Carina, that would cross my line. Now that is an extreme example in terms of Deep Space photography and I'm sure no one would ever do it but I have seen plenty of examples of that sort of thing with landscape astrophotography.

[CapturingTheNight]

and I totally agree. As long as someone is upfront about it (as you have been Mike) then do what ever you want and I will totally respect that person for it and I will be looking at the image for it's aesthetics alone.

[colinmlegg]

Here's one Mike - from 2009. Looking back now I probably could have achieved the same look with a single frame, but back then I struggled to bring up the shadows without adding excessive noise. Combines 2 images, one short exposure for sky and a 2nd longer narrower aperture exposure for landscape.

[Deeno]

Love 'em Mike!
Its what was there, even if you had to 'cheat' to capture it.
Big fan of these composites, HDR, star-trails , ect....

[iceman]

Don't be sorry, it's been a great discussion!


Great photo, Colin! I'd find that perfectly acceptable and doesn't cross my boundaries. I guess the only thing you did differently, was changing apertures for the foreground to bring it more into focus.


Thanks Deeno!

[Octane]

Lovely images, Mike. The glow is superb.

These are fine in my books, too. Although, I do tend to agree with Greg (I'm one of those stinkin' purists), I would be upfront about compositing several images from different times, or systems, etc.

H

[Phil Hart]

nice effort Mike. did you shoot these on sunny white balance and leave that alone in post processing? if so the colours are probably pretty 'real'. certainly the red airglow is.

did you try the half speed option? you could have done a 1 minute exposure at half speed and not noticed any more trailing of either stars or foreground than in a normal 30 second exposure. you'd have kept greg and colin happy and saved yourself the processing hassle? ;) of course that's one stop less exposure than what you got but still pretty good..

and i question (again) this notion that one day technology will make today's 2 minute shot possible in 30 seconds. what is the limiting factor in these shots.. i'd say shot noise rather than 'noise' internal to the camera (which used to be the case). is technology going to increase quantum efficiency by a factor of four? (and yes.. i do have a chip on my shoulder about this! :rolleyes: ;)).

great shots (from the whole trip really!) and an interesting thread.

Phil

[colinmlegg]

Of course there's still that untapped technology going on inside your head, Phil. :P
Copying that should get some pretty incredible images with a 30 second integration. ;)

[gregbradley]

What about using a physical mask over the lens that you hold in place with your hand so the foreground exposure is controlled to be about 20-30 seconds and blocking out the sky then turning the polarie on and masking the foreground section.

Haha ! A true authentic photo Octane grad filters style!

Greg.

[CapturingTheNight]

:lol: That idea is actually not that dissimilar (apart from the tracking component) from the technique know as the "magic glove" that I use to get images like Rising Tide http://www.iceinspace.com.au/forum/showthread.php?t=91345

[iceman]

Thanks H and Phil.

Phil, I didn't try the half-speed option. That would still be a compromise and would end up with slightly trailing stars and a slightly blurry foreground.

I can see it would be useful for those times where a composite isn't practical or possible - maybe the foreground would be too hard to mask or whatever other reasons.

[Analog6]

Fabntastic shots, Mike has said straight up front they are composites so why all the debate in the first pkace? This is more an image in stacked style than an obvious 'insert'.

Anyway, I came to ask Mike if this is just with the basic Polarie. Does one need the $200 fine tracker Polar Axis Scope? I plan to shoot wide shots, not tele lenses.

I do plan to get one soon and try for some good star shots. On that note, at the moment I will be using either Canon 1DsMkII or 40D body with 17-40 f4 lens. Now I realise f4 is not ideal but can't shell out for the 16-35 till I sell the Blad and it is not shifting, I think it likes me and wants to stay here LOL.

What exposures wpuld I be looking at with an f4 lens for these type of scenes?

[iceman]

Hi Odille

You don't need the polar scope. I didn't have the polar scope for any of these shots. Just aligned south with my iPhone compass, and set the latitude (on a very rough scale) to the latitude I was at.

At f/4 you'll need around 1min exposures, which is more than possible with the polarie when aligned. You'll want to use ISO1600 on your 40D. Not sure about the 1Ds.

[AstroJunk]

Great shots, and I think the gentle exageration of the nightscape with some layering of shots is fine.

Greg - I'm largely in agreement with your rule set, but I would be slightly more restrictive on point 2 and demand that all images are taken in a single session (which may be a long one!)

Maybe we take a little lesson from the US National Press Photographers Association: "Editing should maintain the integrity of the photographic images' content and context. Do not manipulate images or add or alter sound in any way that can mislead viewers or misrepresent subjects."