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xelasnave
18-04-2019, 05:31 PM
With the clouds interupting and my early experience with poor polar alignment lately I have gone for not only short exposures but incredibly high gain..upto 450 which I think is breaking the rules...but the exciting thing is that approach has desirable advantages.
Let me list them.
Polar align can be less than perfect although ironically now that I have selected short exposures to manage the clouds I find with polemaster my polar alignment manages 2 minutes unguided...
Two..with clouds around you will need to drop many subs..better dropping 1 minute than dropping 5☺
Three...Short exposure helps give sharp images.
...there are more advatages but I have to go for dinner so what are your thoughts☺
Alex

glend
18-04-2019, 06:30 PM
Don't worry about culling them as you go, use an image grading app to score each sub, saves a lot of time. SGP has a standalone image grader. It will run the contents of a file and sub files, and break them down into filter groups, computing a score and calculating the variance from the mean. I find it very helpful, with no need to eye ball each sub. The app can rename the bad subs for easy deletion or move into another file.

http://www.mainsequencesoftware.com/Products/ImageGrader

xelasnave
18-04-2019, 07:09 PM
Thanks for that Glen.
The ones I cull mainly at that stage is where the camera spits the dummy and half the image is gone..I dont know why it does that..maybe the compiter overloads because I am checking images☺
Hopefully I will be out again tonight..did not get the eight out but for the moment spending quality time with my daughter watching a music vid...but when they go to bed hopefully...you would think I would get sick of it..still stacking for Eta whilst enjoying quality time☺
Alex

easternSea
21-04-2019, 12:02 PM
I am just getting back into this after a long hiatus and this time I had the money to put together a much more advanced rig than before.

The polemaster is pretty amazing for alignment. I swear a good quarter of my night was spent drift aligning. And the Vixen SXD2 mount is much smoother than the old second-hand EQ5 I used to have. So I can now do 10 minute subs as opposed to the 30 second subs I used to be limited to.

But I am not seeing big differences between 15x10 min vs 300x30 sec on the bright objects at least.

Of course, I need some dimmer targets to be sure, but for scratching an itch and to have some data to muck around with on a Sunday, I think there's something to be said for the fast imaging philosophy.

Happy Easter too, if that's your thing.

xelasnave
21-04-2019, 12:15 PM
Mmm I think I would waste half the night sometimes and still did not get pa acceptable☺ although taking star circle trails worked rather well it but most of the time it could be time comnsuming.

The only disadvantage for many short exposures I have found so far is the time it takes to stack..I am working up an Eta Carina image that used mainly 30 sec subs and a few 60 sec subs about 3 hours plus...after stacking them all and running them thru star tools I found due to an alignment error I had to start again...all night the night before last night..all last night and now it says only one hour to go☺ .... so in an hour into star tools to process eight groups and then to photoshop to put them together...
Alex

The_bluester
21-04-2019, 08:22 PM
Having bought one this year I reckon a Polemaster is basically an essential piece of kit.

At the moment I am doing more testing than anything else, but the ability to set up outside the garage and be aligned and running in less time than the camera takes to cool makes it possible for me to do this stuff during the week when I have to work the next day.