Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

A Guide to Smartphone Astrophotography [pdf]

spacemath.gsfc.nasa.gov

Post reply on HN
Print view View original

21–30 of 36 posts

Re: A Guide to Smartphone Astrophotography [pdf]

#21

Post by dekhn »

nshm wrote: post #20
dekhn wrote: post #9

Earlier quoted context omitted.

I don't have any problems in a suburban area of the Bay Area with a small refractor. I can see bright nebulas, etc. The only reason for the big scope in a dark area is if you're trying to look at deep sky objects. You still need a sky tracker to get enough exposures and generally, you want the item centered because that's where the optics are best.

We all know Bay Area is a great place to live geographically ;) Try to find black zone around Chicago for example.

I live in the middle of the peninsula- I can see orange in every direction I look at night. I just think this only matters when looking at DSOs. And generally, cities are bad for astro because of all the heat turbulence.

Re: A Guide to Smartphone Astrophotography [pdf]

#22

Post by dylan604 »

dekhn wrote: post #14
dylan604 wrote: post #13

Earlier quoted context omitted.

Except live view is just that, live just like your eye on the scope. To really get the benefits of a DSLR, you want long exposures like 20sec or longer to really pull in those photons. Then you probably want some auto-guiding to get longer to avoid trails, blah blah. So other than planets, live view will just show the same thing you can see through the eyepiece (black and white). If you're zooming in on the digital z…

You use the ISO setting (which is Gain on a webcam, often not a changeable paramter) which is much better than your eye on the scope. For example, looking at M42 through the Live View, you can easily see all the colors and fainter parts that aren't visible through an eyepiece. It's clearly picking up light the eye doesn't process or report to the brain through an eyepiece. I'm not using an eyepiece. I have the DSLR a…

At that point, you might as well take an HDMI out connected to a larger screen to make it even more visible to those that wander by. I've seen a group do this with a camera designed for purpose that has software running stacking so that the longer the image is being viewed the better the image. They then project this for a larger visible image. Sounds weird as projector == bright light which is frowned up, but they always setup in a way that is not disturbing and since the image projected is pretty dark it's not as bad as one might think. They do everything they can to never blast white.

As far as wowing people, it's pretty impressive. Once they go to the next celestial object, you can watch as the image stacking starts working as you see the fainter object continue to become more and more distinct.

Re: A Guide to Smartphone Astrophotography [pdf]

#23

Post by mgraczyk »

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 pointing it up at the sky.

Re: A Guide to Smartphone Astrophotography [pdf]

#24

Post by shreyshnaccount »

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…

Or get not so good but still pretty decent and cool photos by downloading a port of the gcam app on another android phone. Like i did to get pics of the moon, Mars, jupiter and venus today!

Re: A Guide to Smartphone Astrophotography [pdf]

#25

Post by mgraczyk »

shreyshnaccount wrote: post #24
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…

Or get not so good but still pretty decent and cool photos by downloading a port of the gcam app on another android phone. Like i did to get pics of the moon, Mars, jupiter and venus today!

Would you mind linking to the port?

Re: A Guide to Smartphone Astrophotography [pdf]

#26

Post by groby_b »

dekhn wrote: post #14
dylan604 wrote: post #13

Earlier quoted context omitted.

Except live view is just that, live just like your eye on the scope. To really get the benefits of a DSLR, you want long exposures like 20sec or longer to really pull in those photons. Then you probably want some auto-guiding to get longer to avoid trails, blah blah. So other than planets, live view will just show the same thing you can see through the eyepiece (black and white). If you're zooming in on the digital z…

You use the ISO setting (which is Gain on a webcam, often not a changeable paramter) which is much better than your eye on the scope. For example, looking at M42 through the Live View, you can easily see all the colors and fainter parts that aren't visible through an eyepiece. It's clearly picking up light the eye doesn't process or report to the brain through an eyepiece. I'm not using an eyepiece. I have the DSLR a…

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 :)

Re: A Guide to Smartphone Astrophotography [pdf]

#27

Post by gmiller123456 »

yreg wrote: post #2

I find it funny (but cool!) that this is a full on 190 page book on the topic.

It looks like most of it is just about astrophotography and astronomy in general. There is some specific to smartphones, but even a lot of the example images Hubble/professional images taken with professional equipment. Unless I'm just not seeing it somehow, it seems to be completely lacking in how to affix your phone to your telescope, which would probably the most important thing to know specific to phone photography. Additionally, focusing is a huge issue with phone cameras when dealing with low light astrophotos, and I didn't see anything on that.

Re: A Guide to Smartphone Astrophotography [pdf]

#28

Post by Alakbar »

mgraczyk wrote: post #25
shreyshnaccount wrote: post #24

Earlier quoted context omitted.

Or get not so good but still pretty decent and cool photos by downloading a port of the gcam app on another android phone. Like i did to get pics of the moon, Mars, jupiter and venus today!

Would you mind linking to the port?

https://www.celsoazevedo.com/files/android/google-camera/

Re: A Guide to Smartphone Astrophotography [pdf]

#29

Post by dylan604 »

groby_b wrote: post #26
dekhn wrote: post #14

Earlier quoted context omitted.

You use the ISO setting (which is Gain on a webcam, often not a changeable paramter) which is much better than your eye on the scope. For example, looking at M42 through the Live View, you can easily see all the colors and fainter parts that aren't visible through an eyepiece. It's clearly picking up light the eye doesn't process or report to the brain through an eyepiece. I'm not using an eyepiece. I have the DSLR a…

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 so that the camera is on top facing down putting all of it's weight on the focus tube screw locks. I always try to position it so that it is hanging to the side. I've made that mistake only once.

Re: A Guide to Smartphone Astrophotography [pdf]

#30

Post by shreyshnaccount »

mgraczyk wrote: post #25
shreyshnaccount wrote: post #24

Earlier quoted context omitted.

Or get not so good but still pretty decent and cool photos by downloading a port of the gcam app on another android phone. Like i did to get pics of the moon, Mars, jupiter and venus today!

Would you mind linking to the port?

I can't.. I've tried dozens of them so I've lost track which one actually worked
Post reply on HN