Lookout

[CapturingTheNight (Greg)]

Thank you very much Nicole

Originally Posted by Octane

Greg,

Noting that you took 30 second exposures, you would have to have taken a few seconds to recompose the next image. If this was 8 panels, then, there's 4 minutes of exposure in total, and, a whole bunch of seconds for the recomposure for the next shot. Do you find that when stitching the panels that there's a bit of an error zone where the stars don't necessarily line up? Or, do you not worry about it, considering that it will only ever really be noticeable in print?

H

Hi H,

I have found that it really isn't an issue. Yes there is 4+ minutes between the left of the image and the right of the image, but I am not stitching the left and the right together (if that makes sense). You are only joining one image to it's neighbors and the difference there is 30 seconds. Barely noticeable (if at all) even with the full res.
I also don't have much delay at all between shots. I pre-visualise the scene, level the tripod, compose and take the first shot (usually the left most one) and then as soon as the exposure has finished I move the pan head around abit to the right and press the remote trigger. I would say a maximum of 2 or 3 seconds between shots.
It can be an issue if you are doing a 360 degree pano and coming back to where you started from. Then you can have 10+ minutes difference in the stars positions. But even then you can do a few things to make it barely noticeable. You can start and finish your pano close to the south celestial pole where the star movement is minimal, or start and finish in a fairly featureless area of sky with no 'famous' stars or constellations. I certainly wouldn't try and start and finish a 360 right on the central bulge of the Milky Way for instance.
The most difficult stitch I have ever had was when I did one with a 50mm lens. It was from memory a 14 shot pano, but it was 2 rows of 7. That one took a lot of masking to make right.

Cheers
Greg

[CapturingTheNight (Greg)]

Originally Posted by Ian Cooper

Hi Greg,

congratulations on another fine composition.

Just a few comments about this latest effort, and your earlier posting. You have captured probably more than you might realize. I've added a few lines to your "Aurora In The Alps" photo to highlight what I am talking about.

You will see a pair of curved lines at the top. These mark out a very weak "SAR Arc," also known as a 'proton' or 'hydrogen' arc. This is a quite rare auroral phenomenon and usally only occurs during strong geo-magnetic storms. In my experience Kp6 is the minimum level required to get one. The SAR arc is often sub-visual except where it meets the horizon.

The second picture attached is from the first time I encountered one, unfortunately without knowing it. This rough stitch of 5 photos was taken at the start of an all night Great Geo-magnetic Storm on March 31st, 2001. I used a 28mm (film) lens with 30 second exposures on 400 ISO Fuji Film. The bright red, curved horns on the left and right were actually the base of the SAR arc. The rest of this homgenous band passed through my zenith, if I had bothered to look! I think I was too mesmerised by the uplifted 'discrete' or 'green' arc. To see the discrete arc lift off the horizon is rare from here. If you have a close look you will see Corvus in the eastern SAR arc while Eridanus and Rigel are in the western end.

The 3rd line that I have added to your image is the top of the red rays coming off the discrete arc at the bottom. What looks connected in your image is actually a few hundred km's apart! In other words the SAR arc is well ahead (north) of the main display and therefore it appears higher.

During the Mar 31st 2001 storm the whole display remained stable but was steadily reducing in size, actually receeding southwards, for nearly three hours, then all hell broke loose! If you ever catch the "Breakup" of a major auroral storm then consider yourself really lucky. The first 'breakup' often occurs around 11p.m. (non-daylight time) locally and can last up to 40 mins. There can be several 'breakups' in a night.

This sunspot cycle may have another peak to it going by this last display so hopefully we will all get a chance to catch aurora australis again (with apologies to those too far north to see them.)

Cheers

Ian

Hi Ian,
Thank you SO much for all that. I'm slowly learning a bit more about aurora. Fascinating stuff. They are so rare from my latitude. I saw some great images from Tas with the SAR arcs clearly disconnected from the main aurora. As you say, with my perspective, it looks like it is all one. I will be in Tas in May, so fingers crossed that we have another display like this whilst I am down there.
Great aurora pano of yours by the way. Oh to see a display like that.......
Cheers
Greg

[Octane (Humayun)]

Cheers Greg! I figured it may be like that.

H

[Ian Cooper]

Good one Greg, I hope you have some luck in Tassie in May. It will be the 35th anniversary of my first auroral observation that month. I will be in the bottom of the South Island in May for a conference but unfortunatley just a week before full moon. Still you never know your luck!

Ian

[Ian Cooper]

Greg, what a beautiful, fantastic place! No wonder you want to view from up there. You are so much above a lot of the crud we view through at sea level. We have a mountain range that high (1,700m) to my north east but the highest point you can drive to is just over 900m. We viewed Halley & Hyakutake from up there, it certainly made a difference.

Just eye-balling it from the little map I posted on Colin Legg's thread I would say that your geo mag lat is close to -47, while mine is -46, so we see very similar aurorae. I will post the geographic coordinates to Bob Evans the head of the Aurora & Solar section so that he can convert them and see how close my guess is.

Cheers,

Ian

[colinmlegg (Colin)]

Originally Posted by Ian Cooper

Greg, what a beautiful, fantastic place! No wonder you want to view from up there. You are so much above a lot of the crud we view through at sea level. We have a mountain range that high (1,700m) to my north east but the highest point you can drive to is just over 900m. We viewed Halley & Hyakutake from up there, it certainly made a difference.

Just eye-balling it from the little map I posted on Colin Legg's thread I would say that your geo mag lat is close to -47, while mine is -46, so we see very similar aurorae. I will post the geographic coordinates to Bob Evans the head of the Aurora & Solar section so that he can convert them and see how close my guess is.

Cheers,

Ian

Ian, we are lucky to have you here imparting so many years of wisdom. I always learn something new when you post

I'm just rendering my timelapse that covered the entire night from SW WA. I will post it soon and be interested in your views on how it compares to other KP 6 events you've witnessed.

I was up there with Greg in January imaging from the very top peak. It's a fabulous view and light pollution free from WSW -> ENE. Perfect for aurora viewing. I have a 360 x 195 degree shot that I will post showing the full panorama.

Your 2001 pano is jaw dropping!

[Ian Cooper]

Hi Colin,

we will all be looking forward to those posts.

Re the March 31st, 2001 storm, one local described me as being like a 'farmer in a flood!' To say that I was excited would be putting it mildly.

Cheers

Ian

[marc4darkskies (Marcus)]

WOW! That's just a ridiculously beautiful image Greg! Sublime!

Cheers, Marcus

[CapturingTheNight (Greg)]

Thank you so much for the great feedback Marcus

Originally Posted by marc4darkskies

WOW! That's just a ridiculously beautiful image Greg! Sublime!

Cheers, Marcus

[CapturingTheNight (Greg)]

Thank you so much once again Ian. Yes, it is a wonderful spot for night sky photography. As Colin said there is basically no light pollution to the south at all. Thank you also for the map in Colins thread. It does appear that we are at very similar geo mag lats

Originally Posted by Ian Cooper

Greg, what a beautiful, fantastic place! No wonder you want to view from up there. You are so much above a lot of the crud we view through at sea level. We have a mountain range that high (1,700m) to my north east but the highest point you can drive to is just over 900m. We viewed Halley & Hyakutake from up there, it certainly made a difference.

Just eye-balling it from the little map I posted on Colin Legg's thread I would say that your geo mag lat is close to -47, while mine is -46, so we see very similar aurorae. I will post the geographic coordinates to Bob Evans the head of the Aurora & Solar section so that he can convert them and see how close my guess is.

Cheers,

Ian

[strongmanmike (Michael)]

Better throw my wow in

WOW

Mike

[RobF (Rob)]

Stunning.
Inspiring.
Incredible.
Beautiful.
Moving.
Should definitely be award winning.
And downright fascinating as well (with one raised eyebrow).

[CapturingTheNight (Greg)]

Thank you so much Mike and Rob Really appreciate the great feedback.