First Startrail

[JohnP]

Fay - It's a star trail image so why aren't ALL stars showing trails?

[Fay]

can someone enlighten me? Imay put it on PAIG to find out

[RobertM]

I think you've confused the stacking algorithm.  There looks to be double stars around near the perimeter, although it could be the lens I've not seen that before. 

Why don't you just stack all the images and see if there are any duff'uns.

[Fay]

i stacked in two programs and they came out the same

[mickw]

Fay as Duncan said, I think you may have one or two rogue subs there, perhaps a couple of your test/alignment shots at the beginning ?

Take a look at say the first 3 or 4 images and see if there's a noticeable difference - ie Not part of the "trail" collection.
Also check out the very last images for the same

[Fay]

Well this is better. I contacted a chap I know in Durham & he told me to check the last sub as it could have been moved. when i looked, it was lighter than the others. i restacked & voila, lot better!!

[Carole]

That's really nice Fay.  Apart from it being a much better result with no stationary stars, one thing that also is noticeable is that none of the trails now start with a star "blob" which your first process did in some of the outer trails.

What camera lens did you use.  None of my widefield images come out decent and I wonder whether it's to do with the lens.

Carole

[Fay]

Sigma 10-20 Carole

[Carole]

Thanks Fay.

[Fay]

Thanks Duncan & Mick you were on the trail, so as to speak, but i was already sorting it. Being that the last sub was mentioned & it was lighter than the rest, i thought I would try missing it out in the stack, as all of them looked ok to me 

[JohnP]

much better...! got there in the end Fay..

[RobertM]

I'd agree, miles better plus a small meteor to boot

If frames are much lighter then I ignore them unless I'm desperate otherwise they will destroy your signal to noise.

Hope that helps
Robert

[Fay]

where is the meteor?

[JohnP]

10 o'clock position out near top left. I can even see it on my 3inch phone screen...

[Fay]

oh the feint line John