[androdev]

Let me guess, you have been skipping meals to save up for this gear?

[fiery enzyme]

Fantastic Thread. Thanks for sharing. I did not even know that this existed as a hobby.

[srini1785]

Great. Nice hobby.

Me, personally, I don't see why I need to look at the sky and determine the position of galaxies and planets since by practical experience, I know that I am always under the influence of Shani (40+ years and running).

[KrisTvpm]

Hard to believe, what with the superb photos & professional equipment/software - you started this off as an amateur, graaja!

For an astronomy enthusiast but someone ranking low..down.. on the chain like me, these are no less than Hubble/NASA/ISRO level

Thanks for taking time off to give this detailed writeup with equipment/software details. Some day I aspire to follow your path & be able to capture such beautiful pics of celestial objects. Astronomy has always been a topic close to heart!

Am almost ashamed to post these, compared to yours these are just LKG level! Here are shots of the great conjunction I did with my amateur camera - a humble Nikon Coolpix B700.

The conjunction: Jupiter & Saturn in one frame


Jupiter


Saturn

[graaja]

Originally Posted by haisaikat

Wonderful thread and a unique hobby, I always wanted to own a telescope but never happended. I have one friend living in the Milwaukee who has similar hobby and your shots remind me of him...

Thank you so much for the kind words. And thank you for sharing your friend's website. Those are some fantastic pictures posted there! One of my goals is to photograph most if not all of the Messier objects.

Originally Posted by skyocean

This is very useful information Graaja, thanks once again for the precise sequence of things to do.I will definitely try this soon and post my feedback.
May I ask what's next on the menu ? Do keep us posted if you are planning a stargazing trip anytime in the near future .

Thank you for the kind words! This is galaxy season and many galaxies are in the night sky. I want to photograph some of the major galaxies like Whirlpool galaxy, Pinwheel galaxy, Bode's and Cigar galaxies, Leo Triplets etc. But one problem is the weather. We will have summer showers starting soon here in Coimbatore and clear skies will become scarce. Keeping fingers crossed.

Originally Posted by omranga98

The images are incredible!
I don't have the equipment or much knowledge about this but took these two shots in Darjeeling using my OnePlus 6 and a gorilla tripod
and edited it a bit using a phone app called Snapseed!

Those are nice images you captured with the phone. Try doing multiple captures and stacking the images. You should be able to bring out more details of the milky way.

Originally Posted by androdev

Let me guess, you have been skipping meals to save up for this gear?

Ha ha. A small correction. Three of us (me, wife and daughter) have been skipping meals that contribute to the gear

[Dhar's]

Amazing thread with loads of information. Appreciate your dedication and hard work. Beautiful photographs of the nebula. Looking forward to see more of your astro photography works.

Astro photography makes us realise how minute we are in this great universe. Just a speck of dust.

[mmxylorider]

Wonderful thread and loads of information. While I do have a little bit of interest in Astronomy, Astrophotography will be out of to-do list. That said, for the real enthusiast, quite a few of the National/State parks (here in the US) are designated dark sky parks, where the sky is quite starry due to light pollution control and efforts to preserve that.

Does something similar exist elsewhere, where does one go for a unlit sky.

[ShivrajG]

One Word ! Mesmerizing. This is not a travelogue its a Astrologue . Beautiful pics man Hats Off!

[scatpack392]

Wonderful pictures and a really neat setup Sir!

[graaja]

Originally Posted by KrisTvpm

Hard to believe, what with the superb photos & professional equipment/software - you started this off as an amateur, graaja!
...
Am almost ashamed to post these, compared to yours these are just LKG level! Here are shots of the great conjunction I did with my amateur camera - a humble Nikon Coolpix B700.

Thank you so much for the kind words!

There is absolutely no reason to be ashamed at all. The fact that you noticed the conjunction and put in effort to capture it with the limited tool you have speaks volumes about your interest and commitment. I am sure you will progress over time and capture better and better images.

Originally Posted by Dhar's

Amazing thread with loads of information...
Astro photography makes us realise how minute we are in this great universe. Just a speck of dust.

Thank you for the kind words. You are absolutely right. The scale of time and distances involved in astronomy makes us feel totally irrelevant in both space and time!

Originally Posted by mmxylorider

Does something similar exist elsewhere, where does one go for a unlit sky.

Yes. We do have many such dark sites in India as well. For Bortle class 1, one could go to Leh. The place where I had been in Coorg I believe is definitely Bortle class 3 or lower.

Originally Posted by ShivrajG

One Word ! Mesmerizing. This is not a travelogue its a Astrologue . Beautiful pics man Hats Off!

Thank you so much for the kind words!

Originally Posted by scatpack392

Wonderful pictures and a really neat setup Sir!

Thank you so much for the kind words!

[nerd1200]

Ganesh, Another wonderful thread providing a lot of good detail such that someone who would've wanted to pursue it but did not know how or where to start does now.

Originally Posted by graaja

The Orion Nebula
The Rosette nebula

These images are as good as the ones from astronomy magazines.

[sandeepmohan]

Beautiful captures. Thanks for sharing.

It might be worth exploring the approach of machine learning to clean up your images, because you are dealing with so many at a time. Will require some investment in compute power and data storage.

In my line of work, we do a lot of image rendering. There are two ways you can go about it. Render the image to the highest quality possible, which can take a lot of time (Several hours for one frame). The other approach is render a more noisy frame (Which takes less time) and use machine learning denoise technics to clean up the image. You basically feed or train the system with thousands of images of different kinds. It then identifies what is clean and what isn't and applies a pattern to the noisy image to clean it up. It takes a while to set it up but once you get it going, the results and time saving are significant. We are still experimenting in this space on one of our flagship films due for release in 2023. I have explained this in a very basic way. The subject is quite technical.

[tsk1979]

Originally Posted by graaja

[b][u]F

Guide scope and guide camera: Though a good equatorial mount can track objects within a pixel for long durations like a minute, they will still have some drift and this drift will become noticeable when doing exposures like 3, 5 or 10 minutes or more. This is where a guide scope and a guide camera come in. The guide scope has a shorter focal length and the guide camera has a smaller sensor size. A software chooses some random star from the guide camera and keeps tracking how the star is moving in the frame. Whenever the star drifts on the frame, it issues a correction signal to the equatorial mount. This correction signal along with the equatorial mount's tracking will keep the objects in the same place even for an hour. Below is a graph showing the guide setup working. The solid lines show how the equatorial mount is drifting off in two axes. Whenever there is a drift, the guide software issues the correction pulses (the short +ve and -ve pulses ). As soon as the pulse is issued, you can see how the solid line turns back.

Attachment 2135466

Great thread Graaja!

On your guiding, I see that there is a very significant amount of correction happening. This happens either due to backlash, or due to poor seeing or bad polar alignment. . Are you using multi star guiding. Latest version of PHD2 has multi star guiding feature. You Should use that. Having these corrections would mean you will not get pinpoint stars if you look closely. I do not suspect backlash as your's is a new mount. For polar alignment are you using a camera. Its really useful to use something like iPolar etc., as you can get precise alignment. Alternatively you can use sharpstar etc., or drift alignment

Secondly, colors. Are you using a filter with your 2600? You would at the very least need a IR blocker as ASI2600 (and its twin QHY268M which I use) do not have IR blocker built in. So you need an IR blocking filter. If you image from Bortle 3 or brighter skies, something like a L-Enhance (or L-extreme if you are willing to spend $$$) would be a great investment in cutting light pollution.

For example this image is with a duo narrowband filter, with the moon out.


And this is from a Bortle 9 inner city sky!

[graaja]

Originally Posted by nerd1200

Ganesh, Another wonderful thread providing a lot of good detail such that someone who would've wanted to pursue it but did not know how or where to start does now. These images are as good as the ones from astronomy magazines.

Thank you so much for your kind words!

Originally Posted by sandeepmohan

Beautiful captures. Thanks for sharing.

It might be worth exploring the approach of machine learning to clean up your images, because you are dealing with so many at a time. Will require some investment in compute power and data storage.

Thank you for the details about machine learning. I have no idea of how to go about implementing ML. Is there any software that can do this? The software that I use (Pixinsight) may already be implementing some sort of AI and ML in these processing.

Originally Posted by tsk1979

Great thread Graaja!

On your guiding, I see that there is a very significant amount of correction happening. This happens either due to backlash, or due to poor seeing or bad polar alignment. . Are you using multi star guiding. Latest version of PHD2 has multi star guiding feature. You Should use that. Having these corrections would mean you will not get pinpoint stars if you look closely. I do not suspect backlash as your's is a new mount. For polar alignment are you using a camera. Its really useful to use something like iPolar etc., as you can get precise alignment. Alternatively you can use sharpstar etc., or drift alignment

Secondly, colors. Are you using a filter with your 2600? You would at the very least need a IR blocker as ASI2600 (and its twin QHY268M which I use) do not have IR blocker built in. So you need an IR blocking filter. If you image from Bortle 3 or brighter skies, something like a L-Enhance (or L-extreme if you are willing to spend $$$) would be a great investment in cutting light pollution.

For example this image is with a duo narrowband filter, with the moon out.
Attachment 2136712

And this is from a Bortle 9 inner city sky!
Attachment 2136713

Thank you for these pointers. That is a beautiful capture of the veil!

Polar alignment could be the main culprit here. As I do not have a line of sight to Polaris (I have a building blocking it on the north), I use drift alignment in N.I.N.A or PHD2. I still have about 3 arc minutes of polar alignment error. I need to spend more time in drift alignment and get this right. Right now, I am working on fabricating a pier to permanently fix the mount on the terrace. Once I have this, I will spend more time and iterations on the drift alignment and try to get it to one arc minute or less.

Another improvement I could do is in balancing. Right now, I am using a single 5kg counter weight far from the center of RA axis to balance. The best way to balance is to use more weight and keep the weights as close as possible to the center of RA axis. This will reduce the mass moment of inertia and reduce the load on the RA motor which in turn will reduce the oscillations on the RA axis and should improve guiding. Right now, I have only 5kg counter weights. Two of them is too much even when placed at the highest position on the counerweight shaft. I have ordered a 2kg counter weight. Even on the DEC axis, the setup is a little tail heavy and I ran out of space on my dovetail to move the setup any more to the front. I have ordered a longer dovetail to fix this issue. As soon as the counterweight and dovetail arrive, I will balance the system and do some tests on guiding. Hope it becomes more stable.

Regarding filters, the 2600 does have IR cut filter in front of the sensor. But it does not mention about UV though. All the pictures I took in Coorg are without any filters. For the Rosette, I used a L-Pro filter which should take care of the IR and UV spectra. I may get an L-Enhance soon.



There is one more problem that I need to fix. As there was about 13mm error in my back focus, I have star trails in the corners of the image. I have now fixed the back focus accurately as per William Optics specs, but have not been able to test this due to clouds.

[sandeepmohan]

Originally Posted by graaja

Is there any software that can do this?

Here's one that I picked up from google.

It is worth exploring is all I am saying, to understand if it can help you, or not. As this is a hobby, it maybe too expensive to head down this road. Its a different scenario in film making as we deal with 500,000 images generated a day, on average. Instead of wasting Artist time cleaning up images, we get machine learning to do it. We don't use the above software. Its more in house developed and going through continuous improvement cycles.