SPSP 10 time lapse part 2

[Bassnut]

Pointed at the sky, taken with a modded 40D, 50mm lens fisheye bolt on, 80 odd 30sec exposures at 1600ISO, total time I dont remember.

Enough with the WW jibes OK :mad2:.

[Octane]

lol.

Where's the image?

H

[Bassnut]

Yeah well, it aint flash, how do you get the dots to join?

[Octane]

Fred,

You know what? That looks pretty darn cool. I really like how you've got the pole towards the pole of the sphere itself. Reminds me of the droplets that would appear in LightWave 3D for when you wanted to create texture maps for your models. The trails themselves form the lines of lattitude. Very cool!

I've never tried fixing gaps betwen star trails (I have one I'm working on at the moment). I'd imagine you'd need to find the centre of rotation and rotate the image around that point. But, then, you run the risk of screwing up the trails that are further out in the image as they often curve due to lens curvature.

How long was the gap between exposures?

My understanding is if you wish to have no gaps, then, you need to allow at maximum 700/focal_length as a rest between images.

H

[kinetic]

Fred, H,

I've got a real rough recent result of the SCP.
I will try and dig it out. Edit: posted
I had an 18-55mm DSLR lens at 18mm and used 30sec exposures
but only 10 sec apart.
This , when stacked with no registration(ie straight stack on stack)
gave nil gaps....
Steve

[Octane]

Steve,

That would make sense, because, using the formula 700/18, gives you about 39 seconds to leave as a gap between images at 18mm to avoid trailing.

H

[Bassnut]

Yes, 10 sec gap would do the trick, I think mine were 2 to 5 min.

700mm is to embarrising to try, perhaps "morphing" would do it.

[kinetic]

Actually Fred, it is still there on mine.
A 1x1 view of a crop shows gaps.
The resized down for full screen viewing artificially joins the gaps.

Steve

[batema]

Fred,

I took about 50 two minute shots but only had about 3 seconds gap between shots. I have overdone it with the colours but you can only see the gaps if you zoom in. I used the program star trails.

Mark

[alexch]

Hi Steve, Fred

"Dust & Scratches" filter Photoshop cleans up those gaps reasonably well without destroying the image too much. The gaps on Fred's original image are a little too wide for the filter to do a decent job.

On the attached image I used Radius: 2, Threshold: 12

Cheers,
Alex

[Bassnut]

Yes, the dimmer trails are solid, anyway the joined gaps look OK there.



Thats nice Mark, smooth, the trail colours are good too. I didnt know there was a program just for trails. I had much longer than 3 sec gaps, but then the subs were only 30 secs, too short, which became a problem trying to stretch them all for a video sequence, still working on that.



Thats a good hint, ill remember that.

[jase]

People in glass houses should throw stones punk! :D

Not bad Fred. Artistic angle.

[TrevorW]

Reminds me of "The Time Tunnel"

[gregbradley]

Interesting shot Fred. When I have done star trails I just had the shutter open for several hours. Worked fine.

Greg.

[Phil Hart]

good to see what you ended up with after all that stuffing around with cold batteries eh! i think you could make it better if you removed the one odd exposure at the start (or is it the end?). the regular sequenced images would then look alright..

even when i use 'continuous shooting' mode on the camera so that it is rolling from one frame to the next as fast as it can, i still get (small) gaps in my widefield star trails (which surprised me). i used to try and get a star trail and a timelapse out of the one sequence of images, but have given up and now i go either for either the timelapse (short exposures, high iso) or for a star trail (single long exposure, low iso). having the aperture wide open and high iso for the timelapse also burns out the stars so there's very little colour left. i also still use film for star trails too - no hot pixels and nice natural colour balance in long exposures!

but just think.. you could have got a nice deep widefield shot of the milky way too, if only you had an EQ6 :lol:

Phil

[Bassnut]

Thanks Jase, I chuck em every chance I get ;-).

Trevor, yes the other one is even more pronounced cone effect.

Greg, yes a single long exposure was the otherway, but any hick up (stumble) would have wrecked it.

Phil, I know, theres a couple of stray exposures there, but I couldnt be bothered finding it, although it looks like its the 1st one. Ididnt take the exposures as fast as I could, cause I wouldve ended up with hundreds of exposures and even less battery time.

"you could have got a nice deep widefield shot of the milky way too, ", ummm, and why would I want that ;-)

Have a look at this one http://www.iceinspace.com.au/forum/showthread.php?t=61680 , its got you in it.