Author Topic: M81/M82 should I be masking the core out prior to HDRMT?  (Read 585 times)

Offline STAstro

  • Newcomer
  • Posts: 43
    • View Profile
Hi All

I remember this time last year having major problems processing M81/M82 but that was with my 8.3mpx CCD images with a C80ED, now I am using a faster focal ratio and a 20mpx camera, I am having a challenge using HDRMT as it keeps blowing out the core, so should I be masking out the core early on in the processing cycle?

Regards
Simon
« Last Edit: 2018 March 01 12:09:15 by STAstro »

Offline John_Gill

  • PixInsight Addict
  • ***
  • Posts: 269
    • View Profile
Re: M81/M82 should I be masking the core out prior to HDRMT?
« Reply #1 on: 2018 March 01 12:23:08 »
Hi,

I use HDRMT quite late in the workflow.  With HDRMT  my setting are 8-10 layers, Iterations 1, and enable "To lightness" and "Lightness mask".  I also apply a "range_mask - star_mask" that I created with Pixel math.

Look up
John
« Last Edit: 2018 March 12 23:42:18 by John_Gill »
APM 107/700 apo on CGX mount
ZWO Optics - Autoguiding
ZWO1600mm and filters
... when there are no clouds ...

Offline STAstro

  • Newcomer
  • Posts: 43
    • View Profile
Re: M81/M82 should I be masking the core out prior to HDRMT?
« Reply #2 on: 2018 March 01 13:09:04 »
Thanks John

I generally use HDRMT as the first step after the image becomes "Non-Linear", but just can't seem to get it to work here, I'll try your suggestion on the "Range_Mask - Star_Mask" PixelMath and see what happens

Simon

Offline dpaul

  • PixInsight Addict
  • ***
  • Posts: 121
    • View Profile
Re: M81/M82 should I be masking the core out prior to HDRMT?
« Reply #3 on: 2018 March 01 16:31:19 »
Hi Simon,

Just my opion but the second picture looks great with more detail in the core.

David

Offline STAstro

  • Newcomer
  • Posts: 43
    • View Profile
Re: M81/M82 should I be masking the core out prior to HDRMT?
« Reply #4 on: 2018 March 10 12:44:23 »
Can't seem to get it right, but it's not PixInsight, it's my exposures are too long, they're clipping the whites, so I need to opt for shorter subs, I am afer all imaging at F4 :D