Hyades, Pleiades, California and IC348

[ollypenrice]

Capture and Pre-processing, Paul Kummer. Post processing and high res overlays are mine.

This is about half of a 24 panel Samyang widefield. I couldn't get the full mosaic to work, so far, but I liked this reduced FOV because it shows all of the dust structures in which the Plaiedes participate, along with Hyades and California. It's an hour per panel plus high res RASA data for California, Plaiedes and IC348.

Big version is here: https://ollypenrice.smugmug.com/Other/DUSTY-DARK-AND-MILKY-WAY-TARGETS/i-ZPm459C/A

Olly

Edit: Minor tweak to the image and addition of telescopic data for tiny NGC1333. You'll only see a difference in the full size in the link.

Edited February 9 by ollypenrice

[WolfieGlos]

Gorgeous! So much dust, and so well defined as well.

Is that the Embryo at the top? I didn't realise that area was so dusty, or that there was Ha in IC348 (I blame Stellarium showing it as "just" a reflection nebula).

[Knight of Clear Skies]

Well, that's just lovely, a churning roiling dust field. I don't remember seeing a shot quite like this, showing such a coherence of the branching dust structures. Could be a consequence of such a wide field of view and scale of the region it shows. Is that all of the Perseus molecular cloud in view? Would be interesting to compare the distribution of the radio HI signal.

Here's a slightly wider field of view in IR from WISE (W1/W2 channels):

https://viewer.legacysurvey.org/?ra=62.1268&dec=31.2590&layer=unwise-neo6&zoom=6

The IC138/NGC1333 region is particularly interesting in IR:

https://viewer.legacysurvey.org/?ra=54.4457&dec=31.8272&layer=unwise-neo6&zoom=8

[Laurin Dave]

Very nice Olly, along with Chris I hadn't realised there was Ha to the west of IC348, so something to go after next season  .. 

What was the issue with the larger mosaic? Gradients?  Living in an area with many I've found that the following (rather laborious) method works better than any thing else I've tried ... Crop each panel to remove artefacts..   Run SXT ..  run DBE on the starless image (use normalise image option) .. iterate to optimise location of DBE points..  subtract the optimised background from the original image using Pixelmath..  ($T-Background +0.005) (the pedestal ensures no zeros in the resulting image)  .. colour calibrate ...  save ..   when all complete load into APP as TIFS (it'll throw a wobbly with FITS as it'll ask for all the original subs.. ). 

I've done this on an 18 panel mosaic..  ran SXT overnight then about 2 hours work..  I'd be happy to give it a go.

Dave

[ollypenrice]

1 minute ago, Laurin Dave said:

Very nice Olly, along with Chris I hadn't realised there was Ha to the west of IC348, so something to go after next season  .. 

What was the issue with the larger mosaic? Gradients?  Living in an area with many I've found that the following (rather laborious) method works better than any thing else I've tried ... Crop each panel to remove artefacts..   Run SXT ..  run DBE on the starless image (use normalise image option) .. iterate to optimise location of DBE points..  subtract the optimised background from the original image using Pixelmath..  ($T-Background +0.005) (the pedestal ensures no zeros in the resulting image)  .. colour calibrate ...  save ..   when all complete load into APP as TIFS (it'll throw a wobbly with FITS as it'll ask for all the original subs.. ). 

I've done this on an 18 panel mosaic..  ran SXT overnight then about 2 hours work..  I'd be happy to give it a go.

Dave

Thanks, I'll show this to Paul when he's back at his desk. The issue was partly one of stitching, partly of irregular contrasts and partly of tile artifacts in using Star Xt. The tiles were the biggest hassle, very insistent in one part of the image. It would be good if Russ Croman could fix this.

The wider field would have been of interest if ever we wanted further to extend the Orion-Monoceros image but, when I look up at the night sky and see how far the Pleiades are from Orion, I tell myself to be reasonable...

It would be great to have a single panel, short FL image, to act as a template for these monster mosaics. Could this be an excuse to buy a Leica Q???

lly

[ollypenrice]

1 hour ago, WolfieGlos said:

Gorgeous! So much dust, and so well defined as well.

Is that the Embryo at the top? I didn't realise that area was so dusty, or that there was Ha in IC348 (I blame Stellarium showing it as "just" a reflection nebula).

Above IC348 there's NGC1333.

Olly

[gorann]

2 hours ago, ollypenrice said:

Thanks, I'll show this to Paul when he's back at his desk. The issue was partly one of stitching, partly of irregular contrasts and partly of tile artifacts in using Star Xt. The tiles were the biggest hassle, very insistent in one part of the image. It would be good if Russ Croman could fix this.

The wider field would have been of interest if ever we wanted further to extend the Orion-Monoceros image but, when I look up at the night sky and see how far the Pleiades are from Orion, I tell myself to be reasonable...

It would be great to have a single panel, short FL image, to act as a template for these monster mosaics. Could this be an excuse to buy a Leica Q???

lly

Really great mosaic Olly! Amazing to see how much of it appears connected and interacting. What do you mean by "tile artifacts"? I do run into problems with StarXT, or maybe it is created by BlurXT trying to fix coma in the corner stars of my Samyang 135. After stretching I see these dark areas next to the stars. Here is a recent example (zoomed in):

Cheers, Göran

[simmo39]

Another brilliant shot from the Olly pic factory!

[ollypenrice]

2 hours ago, gorann said:

Really great mosaic Olly! Amazing to see how much of it appears connected and interacting. What do you mean by "tile artifacts"? I do run into problems with StarXT, or maybe it is created by BlurXT trying to fix coma in the corner stars of my Samyang 135. After stretching I see these dark areas next to the stars. Here is a recent example (zoomed in):

Cheers, Göran

It sounds as if you might not have experienced the tile problem, Goran. Lucky you! Here's a section with not much happening in the full version of the present mosaic.

Seeing it equalized makes it much clearer, as does using a hard stretch of the faint signal - which I always want to do.

It tends to be a bigger problem on mosaics and I've yet to work out why it strikes when it does.  The pattern here is not connected with mosaic overlaps which are much larger scale.

I do have some thoughts:

1) The pattern is created both in luminosity and in colour, perhaps more in colour, so I wonder if the debayering algorithm might be interacting with SXT.

2) I use SXT in Photoshop. It might be worth trying it in PI.

3) I stretch in Ps so, ditto, I should try something else.

I do use 'Large Tile Overlap' when running SXT.

Olly

Edit. I suddenly wondered if large mosaics run the PC out of enough memory but I just tried destarring a small crop and the tiles were still visible.

 

Edited February 8 by ollypenrice
Stated

[gorann]

16 hours ago, ollypenrice said:

It sounds as if you might not have experienced the tile problem, Goran. Lucky you! Here's a section with not much happening in the full version of the present mosaic.

 

Seeing it equalized makes it much clearer, as does using a hard stretch of the faint signal - which I always want to do.

 

It tends to be a bigger problem on mosaics and I've yet to work out why it strikes when it does.  The pattern here is not connected with mosaic overlaps which are much larger scale.

I do have some thoughts:

1) The pattern is created both in luminosity and in colour, perhaps more in colour, so I wonder if the debayering algorithm might be interacting with SXT.

2) I use SXT in Photoshop. It might be worth trying it in PI.

3) I stretch in Ps so, ditto, I should try something else.

I do use 'Large Tile Overlap' when running SXT.

Olly

Edit. I suddenly wondered if large mosaics run the PC out of enough memory but I just tried destarring a small crop and the tiles were still visible.

 

Ah, I see what you mean. It has happened to me a few times in an earlier StarXT version. I saw somewhere that Russ explained it as a rare consequence of how the program works by dividing the task up into small squares.

[Mr Spock]

Excellent image. There are quite a few of this area but I especially like the framing on this one. Including the Hyades is a master stroke 👍

[Dunc78]

Wow. Another great Image Olly.