A Guide to Smartphone Astrophotography [pdf] • Hacker News Board

Re: A Guide to Smartphone Astrophotography [pdf]

#31

Post by Deletionk » Sat, Jun 25, 2022, 2:03 PM UTC

mgraczyk wrote: post #23

Plug for my team at Google. One of the cool things in the Pixel camera is an "astrophotography mode", which takes far more pictures than normal with longer exposures. https://ai.googleblog.com/2019/11/astrophotography-with-nigh... You can try it out on any recent Pixel device by holding the phone very still (probably need to mount it) when it's dark. You can get incredible images with no additional effort, just point…

I'm curious if those algorithm would be usable with existing DSLRs.

But I think that the app might do more than just taking a few pictures and calculating stuff on it after.

Is there any CMOS magic it does like reading the chip in a way that it's not the same of taking a few pictures?

Re: A Guide to Smartphone Astrophotography [pdf]

#32

Post by alok-g » Sat, Jun 25, 2022, 6:24 PM UTC

nshm wrote: post #7

Interesting this field is changed significantly last 20 years. One thing is light pollution need to buy a big telescope if you can't transport it to the dark place. You have to drive 100+ from a big city. Second is advanced image processing with deep learning. There is no need for accurate sky tracker anymore, you just shot many images and software combines.

Can you pls. explain more on how to combine? :-)

Re: A Guide to Smartphone Astrophotography [pdf]

#33

Post by groby_b » Sat, Jun 25, 2022, 6:30 PM UTC

dylan604 wrote: post #29

groby_b wrote: post #26

Earlier quoted context omitted.

I think the weight is really the biggest problem. Even fairly light DSLRs weigh a bit, and you'll soon start stacking counterweights. (Which has a lot of potential to amplify vibrations :)

Most mounts can take the amount of weight of your scope plus a DSLR as you probalby have more mount than scope (if you've purchased well), and if you're using an equitorial mount, you using counter weights already. The worst part of the weight is on the focus tube itself. Whenever I'm using my DSLR, I determine where the scope will be pointing and position my scope and camera rig so that it is never going to rotate s…

AltAz, alas.

I still don't get why "camera on top" is problematic, though - unless you're using Newtonian/Refracting? Is there something I'm missing where I'm setting myself up for disaster due to my ignorance?

Re: A Guide to Smartphone Astrophotography [pdf]

#34

Post by nshm » Sat, Jun 25, 2022, 10:56 PM UTC

alok-g wrote: post #32

nshm wrote: post #7

Interesting this field is changed significantly last 20 years. One thing is light pollution need to buy a big telescope if you can't transport it to the dark place. You have to drive 100+ from a big city. Second is advanced image processing with deep learning. There is no need for accurate sky tracker anymore, you just shot many images and software combines.

Can you pls. explain more on how to combine? :-)

I don't know of easy to use software for this, but algorithms are there like in https://benedikt-bitterli.me/astro/

Re: A Guide to Smartphone Astrophotography [pdf]

#35

Post by alok-g » Sun, Jun 26, 2022, 7:34 AM UTC

nshm wrote: post #34

alok-g wrote: post #32

Earlier quoted context omitted.

Can you pls. explain more on how to combine? :-)

I don't know of easy to use software for this, but algorithms are there like in https://benedikt-bitterli.me/astro/

This was a good read. Thanks!

Re: A Guide to Smartphone Astrophotography [pdf]

#36

Post by dylan604 » Mon, Jun 27, 2022, 6:16 PM UTC

groby_b wrote: post #33

dylan604 wrote: post #29

Earlier quoted context omitted.

Most mounts can take the amount of weight of your scope plus a DSLR as you probalby have more mount than scope (if you've purchased well), and if you're using an equitorial mount, you using counter weights already. The worst part of the weight is on the focus tube itself. Whenever I'm using my DSLR, I determine where the scope will be pointing and position my scope and camera rig so that it is never going to rotate s…

AltAz, alas. I still don't get why "camera on top" is problematic, though - unless you're using Newtonian/Refracting? Is there something I'm missing where I'm setting myself up for disaster due to my ignorance?

Oh, I forget people still try to use AltAz for imaging. You have my sympathies for the troubles endured.

I didn't have the focus tube screws locked tight enough. I walked away from my rig for the comforts of my bed while the gear worked through the night. When I returned to the rig, I found that due to the way the rig was rotated in/on the mount ended with the camera directly ontop of the optical tube. Since the screws were not tight enough, the weight of the camera pushed the focus tubes into their most compact state. This clearly blew focus on all of the images from when ever it started to move. I have some lovely out of focus shots of a total eclipse for sale if you're interested ;-)

After that, I learned to manualy rotate my rig through the motion it will undertake through out the night in advance so that the camera is not side slung with the weight never to come straight down like that. I also try to arrange it so that it is always adding tension to the weight so that it is not pulling against the motion.