ithurtssobadly

53 minutes ago, Elp said:

You can get a Black Shark cooler, some people have adapted them onto non cooled astro cameras but they only work due to conduction from the internals of the camera. But that's not your main issue. You're using a tiny sensor, with a tiny lens so your light gathering capability on the sensor is hindered from the off, the phone is compacted so heat builds up quickly on a phone camera sensor too (an external cooler will not remove the heat from the sensor as there's no direct physical link to it from the outside).

What you need to do is take lots of long exposure images without star trailing and stack them via Deep Sky Stacker, Siril or equivalent.

Then you have to post process the image via software, without this you will never get the results you see on the internet, camera raw data doesn't come out any camera like this by default.

Ooh.. thanks! should i use osc preprocessing without dbf script?(in siril)

38 minutes ago, Elp said:

It's just the nature of cameras and how they convert to digital format, you'd need to keep a camera extremely cold in order to minimise it (hence availability of cooled astro cameras which pale in comparison to space satellite cameras). Noise is generated by heat within the camera and sensor. If you take an image in complete darkness you'll see the noise in the image. Noise is reduced (averaged) by total time taken with an image (many many hours) and still noise will remain. The vast majority of AP images will have a noise reduction process applied to the image to get the smooth results every beginner expects.

any way to cool my phone..?

18 hours ago, Elp said:

Cropping the image will have no effect on how a target is framed via your optics. You asked why the outer region is noisy, if you crop it out it'll be removed from the image when you post process further so you won't see it anymore.

makes sense but also why is the image also kind of noisy ?? 
By the way your Location is funny

22 hours ago, Elp said:

Why not just crop the centre of the image into a square then continue post processing?

andromeda wouldnt fit then because my telescope's lowest magnification is 48x
I probably should have gotten a telescope that comes with an eq mount for its low magnification
like example astromaster 130

But i did hear dobsonians were better

21 hours ago, carastro said:

You say you have taken a small number.
normally the more you take the less noisy it is.  Darks  help but nothing beats lots of data. 

Last time i have taken 100 of them but no luck (I deleted them because i was too tired that day not being able to get any data)

I have taken a small number of light images, dark images, flat and bias images. The thing is that after stacking the images it is still so noisy.. It bugs me off about that stacking problem for some reason
I am doing Afocal Astrophotography (deep sky imaging/planetary imaging with a phone)  if that is the problem in this case
The images of Andromeda galaxy non-stacked and stacked are given in the attached respectfully..
But my question is why does still get noisy after adjusting curves to brighten the image? I thought they kind of reduce using dark flat bias frames?
(Why does the dark area around the circle fov get noisy too?)

1 hour ago, Louis D said:

I was reading up on your phone's cameras, and near as I can tell, simply choose lower resolutions.  It will result in lower resolution images, but, for instance, 2x2 binning at 1/2 the linear resolution (1/4 total pixels) results in 4x as much light gathered per pixel.  Give it a try at various resolution levels to see which produces the best compromise between resolution and image brightness.  Lower resolution results in a shorter exposure time to get to the same image brightness (density) as at higher resolution.  If your mount doesn't track, keeping exposures shorter will reduce image blurring as the Earth rotates under the sky.

and should i also use an uhc filter which (possibly) can reduce light pollution?

23 hours ago, Louis D said:

Don't use an ultrawide angle camera lens with an eyepiece during afocal projection photography.  As you've discovered, it results in a massive mismatch in fields of view if you do.

Try using the wide angle and then the telephoto cameras to see if you get a better field of view match.  For night photography, you'll definitely want to do pixel binning with those high resolution imagers behind those camera lenses.

You could try taking ultrawide angle images of the night sky using that ultrawide camera.  Just mount the camera to a tripod and take some images of different exposure lengths to see what you get.

but how do i do pixel binning

I've used sharpcap's collimation to try
But what do you think? Is this collimated?

1 hour ago, Louis D said:

Don't use an ultrawide angle camera lens with an eyepiece during afocal projection photography.  As you've discovered, it results in a massive mismatch in fields of view if you do.

Try using the wide angle and then the telephoto cameras to see if you get a better field of view match.  For night photography, you'll definitely want to do pixel binning with those high resolution imagers behind those camera lenses.

You could try taking ultrawide angle images of the night sky using that ultrawide camera.  Just mount the camera to a tripod and take some images of different exposure lengths to see what you get.

I see. Will try!

13 hours ago, Cornelius Varley said:

The black area around the central image is caused by the eyepiece.

Please upload a jpeg or PNG version of the image so that it can be viewed in the browser.

Ok, here

14 hours ago, Louis D said:

If you are indeed performing afocal astrophotography and the black area outside the eyepiece's apparent field of view is bothering you, buy an eyepiece with an angular apparent field of view wider than the angular diagonal field of view of your camera.

My phone camera is around 120 degree fov maybe.. (using samsung s23 ultra) I can't find anything higher than that

Also is there a way to fix this color noise in my image?

Hello. I just started astrophotography like 1 year ago and I still can't figure out how to counter this (zoom sometimes reset for my camera)
I do smartphone astrophotography and i use Deepskycamera app to take pictures 
Everytime I observe, there's this black background around the circle fov which i really can't get rid of...
Example is the image attached below

This same black background ends up white after stacking all my light dark flat bias frames...
Is there any way i can get rid of it?

Thanks.

Lights_0005_20231031_232140198000000.dng