Ags

I think that’s a great improvement!

What was the imaging scope / camera combination?

It works fine for me but the source of my image file is DSS. Possibly images generated by other programs are not supported? Even if two programs generate the same format, they may use different optional features of that format...

I saw a bright star turn a very small part of the sky blue. Mizar through fairly thick cloud.

I carry my RC6 and mount out in one go, that’s one minute. Then it cools as night falls. Carrying it from its sheltered spot to the Scope Operating Zone is a minute, including rough polar alignment. Nailing polar alignment is two to three minutes. Then there’s five minutes calibrating the guide scope and fussing over focus. Maybe 10 minutes all in all.

This books coming along very slowly. My laptop has died last week, waiting to get it repaired before I can continue.

Free 😀

No idea, but try free GraXpert 3 on your linear data. It has AI gradient removal and AI noise reduction. I think it's brilliant.

On 22/10/2022 at 15:44, gorann said:

Yes, but we amateurs also use NB filters and I never seen or heard of bright stars completely disappearing. However, maybe they do, some apparently only show up in IR. I had a look at Liverpool Telescope HaRGB data (a 2 m RC on La Palma) that I processed several years ago (https://www.astrobin.com/286659/). And, those additional star seen in the JWST image are NOT there, so clearly JWST Near-IR images reveal stars that we do not see in visible light. I am still puzzled.

Cheers, Göran

Dust stops light with a wavelength smaller than the dust grain size. So longer wavelengths pass through dust like it’s not there. I have been meaning to try a NIR filter on a partially transparent dust cloud like the Iris Nebula to see if it can resolve any hidden stars.

On 27/04/2024 at 07:38, josefk said:

I’ve never looked through a Mewlon. I guess (purely from reading the experiences of others) the Mewlon will be better than the CC8 on axis but the DK prescription of the Mewlon would be worse than the classical cassegrain prescription of the CC8 off axis. Off axis is important to me. I use the field stop quite a bit so I like things tidy fully across the FOV. 

I saw a spot diagram for the Mewlon 180 once - off axis performance is unbelievably poor according to Takahashi’s own diagram.

5 hours ago, Vash said:

Astrosharp

I find Astrosharp provides a fairly good sharpening without introducing artifacts or making noise worse, as long as you don’t overdo it.

3 hours ago, MarsG76 said:

try Astro Denoise PY 0.5.2 for noise reduction....

I think that is created by the developer of GraXpert, which now features a very powerful noise reduction ability too.

@Vash I am using a script, I got it from here:

https://siril.org/tutorials/star-reduction/
 

I find it works best if the stars are not too bad in the first place. So be careful with initial stretches…

Using Astrosharp for decon and better stretching in Siril. And more data.

Got better (and more) data last night.

This was captured on a 99% Moon night, with strong city light pollution too. I only got an hour between clouds and I am using an uncooled camera so the image is dominated by noise. I am trying to get my stars smaller and get a bit more contrast and detail in the galaxy.

My process is currently:

1. Graxpert removes the gradient and denoises the image.

2. Siril removes green noise, does a photometric color balance, and does a first stretch.

3. Astrosharp does the sharpening.

4. Siril does a star reduction.

5. Final tweaks to the histogram in Gimp.

Great capture!

I've been playing with Astrosharp this weekend, and I am quite pleased with the results so far. My test data is very noisy, I am hoping to gather some cleaner data tonight.

However, the Astrosharp docs are nonexistent so I am not clear about the finer details of the tool. Which model is best to use - I am assuming Dual PSF for now. There is also an Astro clean model, but that seems to be a fairly potent noise reduction model? Has anyone out together a page describing what the different models do?

Better software and better processing will definitely help, but for now I am focusing on trying to get more data and get the basics of processing right. 

Svbony’s sales blurb makes a point about the eyepiece being well suited for “premium refractors” so that makes me think the curvature is matched for those grab and go apos and not a big newt. I can’t say I’ve seen curvature in my 66 or 90 mm refractors. I love this eyepiece, it gives everything from one degree FOV to max magnification in the fracs, so I don’t need any other eyepieces!

Ah no, forgot. I was racing cloud.

I had a bit of clear sky and tried out the mount with its updated handset. No difference in goto accuracy unfortunately. Added 30 minutes to M51 but then the clouds came back!

Downloaded and tried Graxpert for the first time today. The noise reduction and everything else  works very well for me (standalone Windows version). Why not add sharpening and star reduction as well? You know you want to 😃

I turned the noise reduction dial of Graxpert 3 to "11".

I was using the hand controller, I just never bothered putting a battery in the hand controller or setting up date/time on it - I thought that would all come from the Air... The air does set some info like location, but not all, it would seem.

I object to setting up the hand controller. Having two sources of time and location information is very, very wrong and asking for trouble. But it is what it is.

Now of course I have to babysit the setup through a few meridian flips as by attempting to fix the goto I might have broken the flips.