steviemac500

What is the best way to construct an LRGB mosaic. I am using APP and have not had much luck with my data recently. I want to know if i should create a mosaic of each colour first then combine them in PI or if i should create separate RGB panels and colour calibrate each panel separately then construct after that? I was having real issues with colour being off between frames. Thanks, Steve

I'm only posting this as I've had a nightmare trying to complete an RGB mosaic of Andromeda. Getting the field illumination matched and the colour calibration correct across the panels (6) was just beyond a joke, especially where the frames meet. I had to shoot an extra panel to fill in a tiny gap between frames too. It has been valuable experience but has shown me that I need to do more RGB shots as I am very much out of practise. So this is the L only of M31, 7 panels of approx 5 hrs each not looking great!!! The mosaic was constructed using APP which i cant fault and some post processing done in PI - I am now moving on from this target and treating it as a learning experience. It doesn't always go right!!!

?I think we’re agreed it’s a bit odd. Morphological selection but tbh I didn’t really spend as much time as I normally would and I only did one pass too.

Only one pass, but yes I think it looks a bit odd too ?. Like they’re an after thought put in with a very light pencil.

This is a 4 panel mosaic consisting of 24 x 1200s in 7nm HA. Shot over a few nights in my BYO. Mosaic was constructed in APP (great software) and then process in PI with a heavier contrast than normal and LHE to bring out the bubble more. I also did one with the stars reduced but not sure which i prefer? Cant decide whether to add RGB to this or leave it as stand alone HA. CCs welcomed as always, hope you like it. http://astrob.in/321080/0/

? I added them later with ps!

Hi, it’s my ED80 and Moravian G2-8300.

This is a 4 panel mosaic consisting of 6 hrs in each. Captured with a Baader 7NM HA filter. Processed in PI and the mosaic constructed in APP. I added a few diffraction spikes in PS just because I like them! Shot from my BYO in Cyprus. Hope you like it! http://astrob.in/317111/0/

Thanks everyone!

I shot this whilst collecting data for a mosaic I'm making and I'm pretty happy with the result. Its only 8 hours of total integration but its come out well i think. Taken over 2 nights form the BYO in LRGB. Processed in PI with a bit of NR and then a final touch up in my trial version of APP. C/C welcomed as always. http://astrob.in/316689/0/

I've been taking some subs of this to fill time before my Flaming star/Tadpole mosaic becomes available later on. 45 x 1200s in HA. Processed in PI. Combination mask used to allow LHE to target the nebula and to sharpen the detail. I will probably add some O3. Hope you like it. C/Cs welcomed as always. http://astrob.in/315891/0/

Thanks Sara, I appreciate the help.

I spent some time this morning doing that with my red data and I have to say the mosaic construction is impressive. Much easier than PI and no pinched stars to deal with.

Sara, any idea when i process the stack in APP i get this glow on either side yet when i use exactly same cal frames in PI it comes out perfectly? Is there a setting i have wrong - it looks like a cal issue.

Thanks. Don't go anywhere.......I can see me needing more help. Really good videos by the way.

Thanks Sara. So if I go back and calibrate each panel separately then play with the settings for the mosaic after that?

Yes, it does Sara. Any tips on getting these seams sorted? I've tried all sorts of variations!!!!

Having gotten a liking for mosaics and after reading Sara's write ups, i have been trying the trial version of APP. I'm having a few issues though..... 1. I find it incredibly slow - the idea of being able to feed it all my frames and then have it generate the mosaic is amazing but as soon as the number of frame increases, the time it takes to process jumps massively. E.g. I am currently building a 6 panel of M31, i loaded the Red frames this morning at 0830 and it has just finished at 1600. Granted there was a total of 137 frames to sort but it still seems a long time. 2. After this large integration, there are loads of issues with seams even though it has clearly made an attempt to improve the joining of the panels. But 8 hours is a long time to wait to find that the end result is this. See below - i have attached the result of this morning one before any adjustments and the other after cropping and light pollution removal and a stretch in PI. Is anyone having better luck with this amount of data and can offer advice, particularly with the seams?I think this software could be great but I'm struggling to justify the cost at the moment.

it seems to be moon LP. The shots from last night from the second panel of with the 38% moon are much better.

Anyone?

I have to admit it's been a while since I've done any LRGB shots - mainly NB. I'm shooting a mosaic of M31 and stupidly shot whilst the moon was up and took in some quite bad LP into my shots. I'm using my G2 -8300 with 1.25" internal filters. I know there is some vignetting but normally my flats have taken care of this and I have had no trouble with any of my NB shots. However, the rings in the corner of this is typical of all 6 panels and I'm not confident I know what it is. Do you think the moon LP has exacerbate the vignetting on these and will reduce as the moon goes away? I've also noticed that the dust motes haven't been taken care of either and the flats match these up perfectly so I'm sure they are ok - again no issues with the NB stuff??? Thanks. Edit - I should add that these are simply autostretched to highlight the issues.

Dammit, I was hoping no-one noticed!

I had real trouble with the o3 data and spent 3 days battling the mosaic construction. Had issues with intensity across the panels which Dlinear fit eventually sorted. There are still some issues with visible seams but I got fed up toward the end. So this is a 6 panel mosaic. 5 hours in HA and Oiii in each panel for a total of 60hrs. I might go back to this but I need a change of target!!!? http://astrob.in/309066/0/

Thanks Olly. The unprocessed panels are below with an STF applied. To my eye there is a hint in the Network and more so in the Triangle. The conditions here in Cyprus have been consistently good so I trust the data but I do think that ABE has exaggerated it in both. See what you think........

A little Sara. The biggest problem was uneven brightness in one of the panels which seemed to sort itself with a couple of more goes at registering. I had to play about with the feathering as I was getting a few pinched stars on the borders but I'm pretty happy now. The Pelican I did felt much easier ?