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alocky
24-10-2015, 05:14 PM
I've loaded a timelapse of my "unattended" imaging session last Saturday, https://flic.kr/p/zSF2gS
and here's (http://www.astrobin.com/221663/B/) what the 10" was doing on M74.
One basic mistake - I hadn't connected the secondary mirror dew-heater as it's no longer necessary this time of year, and the wire had unclipped from the secondary spider, so I earned an extra fat diffraction spike at 45 degrees to the usual from dangling cables.
Another thing I've noticed is that the meridan flip has caused a collimation shift, so the red channel (post-flip) is causing a few flares on stars.
Anyway - 10 minute subs, 8 for each channel in LRGB, QSI683wsg camera, losmandy G11.
Once I sort out these issues, this will be a great target to revisit with this scope!
Andrew.
Thanks for looking.

ReaPerMan
24-10-2015, 06:33 PM
There is always something isn't there. It what makes Astrophotography so challenging. The striving to get the good picture is a dance of knowledge, skill, hardware, software and of course a seasoning of luck. Nice target :thumbsup:

Placidus
25-10-2015, 06:21 PM
The M74 is good, but the video is excellent!

DJScotty
25-10-2015, 07:02 PM
Very rarely is there a trouble free imaging session. But a great image nonetheless.
I agree with mnt the video is excellent

blink138
25-10-2015, 07:52 PM
where was the video taken andrew?
pat

alpal
25-10-2015, 08:14 PM
Hi Andrew,
you picked a tough target with a very low surface brightness.
You might be able to get a bit more out of your
picture if you make a pseudo luminance layer from the RGB data & blend it with the actual luminance.
The video is interesting too.

cheers
Allan

glend
25-10-2015, 08:17 PM
I can never resist zooming in on these images. When zoomed in I noticed two more small galaxies in the shot in the 7:30 position down near the bottom left (if looked at as a clock face with 12 noon at top).
Draw a line through the three bright stars in a straight line on the right side of M74, carry your view onalong that line to the lower left just abve the bottom are to two faint background galaxies.

alocky
26-10-2015, 12:03 AM
Thanks Glen - I've probably been a bit harsh on the black clip, as in the raw stretched luminance image they're everywhere. It's amazing to think we can image these anonymous gx with such small scopes these days.



Thanks Allan - I'll definitely revisit this one next month and get some more data too.



Hi Pat - it's a nice open area out near Talbot Hall, just 10 minute this side of York. Usually infested with a few >20" dobs around new moon...



Cheers - the D800 has a built in timelapse mode that's pretty foolproof!


Thanks MnT - glad you enjoyed it!



I don't think I've ever had a night's imaging go smoothly! Like you say, there's always something. This time the meridian flip failed for no apparent reason too. It's as if the thing has moods...

gregbradley
26-10-2015, 07:59 AM
That looks great Andrew. One of my favourite galaxies and one I have been waiting for to rise to image fully.

You can run a bit of deconvolution on the red subs to help match them.

Greg.