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PaulSthcoast
16-06-2024, 07:17 PM
Details as follows:
Hi everyone,

Another post from the clear night 22.06.24

William Optics Zenithstar 81mm
.08 reducer flattener
Zwo 1600mc no cooling
(ambient camera temperature was -3.6)
IDAS LPS2 filter
30 x 120 seconds unguided
Sywatcher azgti

Stacked via asi air.
Processed in Snapseed.

Thanks for looking.

Paul.

Mickoid
19-06-2024, 11:30 AM
Good to get these two classics in the one frame Paul. I have to agree with Martin though, The LP filter is not necessary under dark skies and it's killing your star colours, which always add to a pleasing astro photo. Well done on 2min unguided subs, your Polar Alignmemt must have been very good but in using the LPS2 filter, the extra nebulosity and dust that could be revealed without it has been lost. I'd love to see a comparison shooting the same object, same exposure, from the same location without any filters, except for perhaps a UVIR cut filter if required.

PaulSthcoast
19-06-2024, 05:14 PM
Hi Micheal.

Thanks for your comments.

The main reason I used the IDAS was simply because I couldn't find my 2 inch IR/UV filter.

Rather than loose the opportunity to get some images I went with it.

The IDAS filter is described as following:

Unlike other light pollution suppression filters, IDAS filters are specifically designed for balanced color transmission using the IDAS unique Multi-Bandpass Technology (MBT) process. The balanced transmission allows color photographs to be taken with minimal color cast to broadband emission objects such as stars, galaxies and globular clusters.

Full product info in link here

https://cloudbreakoptics.com/products/idas-light-pollution-suppression-lps-filters-p2

Happy to do a comparison with UV/IR and no filter.

As for the unguided subs.

Yep, as Martin would agree, the mount and PA are the foundations to good imaging.

Thanks again.

Paul.

carlstronomy
19-06-2024, 06:58 PM
Paul

Really nice image for one hour integration, you have some nice detail.

I had a look at your image and noticed you took down the red channel too far.

Try to keep your values of all the channels even and not so low.

Bring some red back and your stars look super nice.

Carl

PaulSthcoast
19-06-2024, 10:14 PM
OK.

So, as requested by Micheal, 30 x 120seconds with UV/IR.

Thanks for looking.

Paul.

Startrek
19-06-2024, 11:12 PM
Paul,
Near full tonight overhead ( I’m currently imaging M8 and my backyard is like daylight )
Using a UV/IR or Lum filter under near full moon is like waving a red flag to a bull , severe reduction in SNR and colour spectrum
Give it a comparison during new moon and I’m sure you will pull more detail and colour given same integration time
Cheers
Martin

PaulSthcoast
19-06-2024, 11:36 PM
Thanks Martin,

yep I know but a comparison was needed.

Hence the sky map.

Besides, who knows if this clear sky will last ?

Paul.

Mickoid
20-06-2024, 09:53 AM
Thanks for showing us the result with just the UVIR cut filter Paul. By the looks of it there is very little difference between the two in terms of nebulosity and detail revealed. I'm just surprised that the UVIR cut filtered one didn't show more star colour in this region but perhaps 120 second subs has overexposed the stars in a dark sky. Like Martin said, a near full moon is going to play havoc on colour balance. Either way, a true comparison would need to involve identical conditions, preferably conducted on the same night and the captured data processed using the same workflow. You were definitely lucky to get another clear night to experiment and taking advantage of that is what you have to do at the moment with the way the weather is. :thumbsup: