Jump to content

NLCbanner2024.jpg.2478be509670e60c2d6efd04834b8b47.jpg

Failed Moon Mosaic! Looking for tips


Xiga

Recommended Posts

Evening all

I had a 1st attempt at doing a moon mosaic recently using my C8 and Canon 60D. Things didn't go too well, firstly i waited too long to get started, meaning i lost the moon to my neighbour's house before i could finish, plus i'd say at least the last quarter of my captures were tainted due to the view being partially obscured by the neighbour's satellite dish and then gutter before it disappeared alltogether. I could tell simply based on how dim and murky the liveview was getting over time. 

Anyhoo, i thought i'd give it a go at processing anyways, just for some practice as i've never done a mosaic before. I had 44 captures to play with, each one about 45 secs long at 60 fps and using the movie crop mode of the 60D. I converted them to avi files using PIPP, then stacked the best 10% for each in AS! (so about 2,700 frames in each). I also outputted the autostakkert _conv sharpened files as well, even though i know they are over-sharpened.

I then di my own sharpening in Registax 6 for each one. I didn't spend long on each one admittedly, mostly just cranking up Level 1 fairly high, with a little of either Level 2 or 6. The effect was definitely more subtle but far superior to the AS! sharpend ones. 

I then used Microsoft ICE to stitch them together. However, it would only work with the AS! _conv sharpened files, it simply would not work with my own sharpened images. Does anyone have any idea why this might be? Id' be gutted if i had another go and was forced to use the over-sharpened files.

Furthermore, as you can see from below, i also missed out some sections. I've done some reading and i think i might know how to avoid this in future, but i'd like confirmation first (or a better method if one exists). Does one avoid this by having the camera oriented in such a way that when i slew right, that the camera moves in a horizontal line? i.e insert the camera and take a long exposure of a star while slewing right or left and watching the star trail that gets traced. Then repeat as necessary until you get the star trail as level as you can get it. Once done you are then free to make a start on the mosaic. Is this right?

Lastly, if anyone has any processing tips, such as making sure none of the seams are visible, then i'd love to hear them. I'm a total noob when it comes to this stuff! lol

Can't wait to have another go now, as even though the image below is just a very rough approximation of what i should be able to achieve, i'm excited to try and put together a high resolution image that will hold up well under a fair bit of zooming. Will be a lot of work to complete even a half-moon on this evidence though. But that's ok, i like a challenge ;-)

 

 

3783__MVI_3783_pipp_g3_ap72_conv_stitch.jpg

Link to comment
Share on other sites

I see you have an HEQ5. You could link this to EQMOD which has a mosaic option to ensure nothing is missed out.

I did an unplanned Moon mosaic a few weeks back, didn't use EQMOD, and so missed a chunk! Had to insert a slice from the next day but conditions weren't so good. I stitched this all together using Hugin.

You have to be systematic and plan plenty of overlap. It gives you more leeway when cropping too. One thing Hugin requires is that all frames be the same size. Could be why you couldn't mix and match yours. Also, make sure you apply identical post-processing (assuming capture done on one night) to each stack as this may be the cause of the seams showing.

Moon_Mosaic_C.jpg

Link to comment
Share on other sites

With what you have there Ciarán is some great lunar detail, well done.

It's a shame about the overlapping issue as it's a lot of work to do large mosaics. It's better to overlap more than than you think than not enough. Good processing advice there from Jokehoba.

Link to comment
Share on other sites

When you have made your panes you will need to crop them all to get rid of the stacking artifacts around the edges.  These are the "lines" and "white strips" that are clearly visible around each pane in your stacked image.  If you do that you should find that the stacking software (MS ICE or whatever) will stitch your images together.  You seem to have just enough overlap to do that.  As said you need more overlap than you think to make a successful mosaic - I generally go for at least 20% but 30% is better if you can manage it.

Link to comment
Share on other sites

Jokehoba that's a superb image mate! I see you too have an 8" SCT and a Canon DSLR, if i can achieve anything even close to what you have i'll be well chuffed.

That's a good idea about Eqmod. I do actually use it in conjunction with my HEQ5 Pro for Polar Alignment and for platesolving within APT, but i hadn't thought about using it for a Moon Mosaic. Actually, up to now i haven't really been using my netbook at all for any planetary or lunar imaging, i've just been using the camera screen at the scope, but i feel it might be time for a trial run (once i've checked out the Eqmod video on youtube first of course!)

I had a very quick go at using Hugin, but i was totally lost tbh. It looks a lot more in-depth than MS ICE, but is definitely not as plug-and-play. 

Roger, i don't know why i had forgotten to crop my panes! lol. I guess i just thought if MS ICE was able to stitch the first lot of panes together ok with the over-sharpened files from AS! then i didn't think it was necessary. But i went ahead and cropped them all. Alas though, it made little difference as MS ICE still refused to stitch any more panes than those in the OP. I really under-estimated the amount of overlap required, and as it turned out most of the subsequent panes had either very little overlap, or sometimes even none at all to work with, so it's not that surprising in the end i suppose. Plus, the latter panes were significantly darker and murkier than the ones at the beginning, so in the end i had to stitch the rest by hand in PS. This turned out to be a complete PITA, due to the unequal illumination of each pane (plus my rudimentary PS skills didn't help either! lol). I presume that under normal circumstances (with no clouds or obstructions to deal with) that unequal illumination is not something one normally has to worry about is it? I've heard it's better to cover the entire terminator first, as it's the part that changes brightness the quickest, but do most stitching programs usually handle brightness smoothing in addition to alignment? 

One last query (sorry!). Considering that another attempt at this is going to require me to be capturing at the camera for over an hour, do i need to worry about re-focusing at any point, or will that just introduce a risk of ruining things altogether? I'm not too sure how confident i would feel about focusing by hand on the lunar surface mid-capture, after first focusing by bahtinov mask.

So the final image is attached below. Again, due to the uneven illumination across panes it's a bit rough in places to say the least, but it was fun to put together nonetheless, even though i knew it would be forever incomplete :-(

Moon Mosaic_incomplete.jpg

Link to comment
Share on other sites

Good first attempt. It is easy to miss a bit, if you have a lot of movement some times you can force the software to stack more of the pane. but this only helps if the bits missing are slight.

EQ Mosaic is worth getting into I think. I plan on trying myself at some point.

Link to comment
Share on other sites

On ‎6‎/‎7‎/‎2016 at 13:46, Jokehoba said:

I see you have an HEQ5. You could link this to EQMOD which has a mosaic option to ensure nothing is missed out.

I did an unplanned Moon mosaic a few weeks back, didn't use EQMOD, and so missed a chunk! Had to insert a slice from the next day but conditions weren't so good. I stitched this all together using Hugin.

You have to be systematic and plan plenty of overlap. It gives you more leeway when cropping too. One thing Hugin requires is that all frames be the same size. Could be why you couldn't mix and match yours. Also, make sure you apply identical post-processing (assuming capture done on one night) to each stack as this may be the cause of the seams showing.

Moon_Mosaic_C.jpg

Whats your experience like with EQ mosaic I want to try it soon in a big way, with a ASI 290 And SW 300P

Link to comment
Share on other sites

19 hours ago, Xiga said:

 I see you too have an 8" SCT and a Canon DSLR, if i can achieve anything even close to what you have i'll be well chuffed.

You have all the same tools! I used APT in LiveView mode, zoomed in x5 (works better than full-frame), and manually focussed. Then used the Planetary feature (the Record LiveView option) to capture 300 frames. APT places them nicely in a folder under LV. Then used Registax, taking the best 150 frames per tile. Cropped each to all the same size for stitching together.

Link to comment
Share on other sites

16 hours ago, neil phillips said:

Whats your experience like with EQ mosaic I want to try it soon in a big way, with a ASI 290 And SW 300P

I confess that I haven't used it (:hiding:), just know it's there.

But having just watched Chris Shillito's video tutorial again, I realise that it's very straightforward, and only a click away. It would have saved me missing that segment! I will definitely use it in the future, especially as I am planning to do a mosaic of M31 come the autumn.

Link to comment
Share on other sites

May i suggest that next time you try to get a mosaic of just one part of the Moon - maybe four panes high and wide - with overlap?  That way you can make a decent mosaic and perfect your technique.  If you have time then maybe try a second similar area.  As your experience grows you can work towards getting a full disc.

Don't forget that the image of the Moon gets bigger as the Moon approaches full - and this takes more mosaic panes to cover it!

Also the trick with the "terminator first" is due to the lunar "sunrise" or "sunset" moving surprisingly quickly across the image.  if you take a terminator pane and then the "next one" an hour later your stitching software may well refuse to stitch them together! So run a set of terminators first and then build up the rest of your mosaic.

I use imerge to help me.  This takes the first frame of your avi and allows you to manually make a rough mosaic of these first frames on a "blank canvas".  Very useful if you want to avoid the "missed a bit" club.  Its old software and a bit clunky but it works!  http://jaggedplanet.com/imerge.asp

Link to comment
Share on other sites

2 hours ago, Jokehoba said:

I confess that I haven't used it (:hiding:), just know it's there.

But having just watched Chris Shillito's video tutorial again, I realise that it's very straightforward, and only a click away. It would have saved me missing that segment! I will definitely use it in the future, especially as I am planning to do a mosaic of M31 come the autumn.

I just need a usb interface between EQ MOSAIC and my neq6 mount. think flo sells them. what interface are you thinking of using ?

Link to comment
Share on other sites

18 hours ago, neil phillips said:

I just need a usb interface between EQ MOSAIC and my neq6 mount. think flo sells them. what interface are you thinking of using ?

I have a Hitecastro EQ Direct cable, which was bundled with the NEQ6. It looks like that's what FLO supply. Works a treat.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.