2889 replies to this topic

[Lucas Bittar]

Hi! I'm new to astrophotography and have been reading a lot about using webcams for planetary imaging (prime focus method). This is my question: what are the advantages of using a webcam over a smartphone camera (afocal method)? I understand that resolution isn't important and that frame rate is what matters, so that having a fancy high-res camera doesn't make a difference. But I see most people recommend Microsoft's Lifecam Cinema Webcam, which shoots at 30 fps 720p. Why should I shell out the money for that if I already have a Samsung Galaxy S7, which shoots at 60 fps 1080p? Are there any other advantages to using a webcam other than frame rate? By the way, I have an adapter which allows me to mount the phone to the eyepiece, so stability isn't an issue.

[Den25]

Hi! I'm new to astrophotography and have been reading a lot about using webcams for planetary imaging (prime focus method). This is my question: what are the advantages of using a webcam over a smartphone camera (afocal method)? I understand that resolution isn't important and that frame rate is what matters, so that having a fancy high-res camera doesn't make a difference. But I see most people recommend Microsoft's Lifecam Cinema Webcam, which shoots at 30 fps 720p. Why should I shell out the money for that if I already have a Samsung Galaxy S7, which shoots at 60 fps 1080p? Are there any other advantages to using a webcam other than frame rate? By the way, I have an adapter which allows me to mount the phone to the eyepiece, so stability isn't an issue.

I'm curious about this, too.  How can you get a decent image with a smartphone?

[SeaBee1]

I have found that smartphone astro photography is difficult at best. I can get fair pics of the moon, but the camera hasn't been able to "latch onto" anything else. Just not enough light coming through the eyepiece, even on Jupiter or Saturn. I use an adapter to attach to the eyepiece, but it doesn't help with anything less bright than the moon. I did get lucky last spring and got a pic of M42 but I was not able to repeat it. The following is the pic I took of M42, the Orion Nebula, with my Celestron 102 XLT Omni...

 

 

And next is a pic I took of the crescent moon last weekend with my 10"...

 

 

Not first rate quality, as you can see... passable if you just want to say "I took these", but not really astro photography. If you REALLY want to take astro photos, I think you will need to open your wallet and get the proper gear...

 

But this is just my opinion based on my experience... YMMV

 

Clear skies!

 

CB

[Dartguy]

Here are a couple of handheld with a Samung G6

 

 

 

[Vesper818]

Someone in the outreach forum recommended this little gadget.

https://www.amazon.c...0?ie=UTF8&psc=1

I just got one in the mail yesterday, but have not tried it out. Nicely made, all metal, and clips firmly onto my Samsung galaxy with a padded clamp. The ring with 3 set screws should be adjustable for most standard 1.25 eyepieces.
It will be my first attempt at "astrophotography". But I'm also curious if it would work well to turn the phone into a vidio viewer.
Should be entertaining !

[Pinbout]

 

shoots at 60 fps

 

that's good

 

I could never get my phone to expose the planets correctly.

 

 

the moon...is different

 

 

and the sun is another PITA

 

Edited by Pinbout, 11 September 2016 - 10:30 PM.

[bleep]

Try googling iastrophotography   Theres tips on how to take pics with the iPhone that might help

[sg6]

Primary difference is that with a smartphone you have a lens infront of the actual camera sensor so whatever light is entering that really needs to be collimated light, so you therefore need an eyepiece in the scope.

 

With a webcam you remove the lens from the webcam, leave the filter in place and then you focus the image from the scope directly on to the sensor.

 

For planetary imaging you generally take a video so the camera needs top be held immobile for say 60 seconds. You as a person cannot do that, but a webcam holder on a scope more or less can.

 

A smartphone will also I half suspect sort of do its own thing, you do not in effect have the control over the smartphone camera that you would over a webcam for setting assorted functions.

 

People point at the moon and get an image but the moon is the one object that falls into almost "normal" photography. I have found that with the moon the DSLR I have will determine correct exposure and the autofocus (spot) is fine on it. In effect the moon is bright enough for a DSLR in Auto whereas most (all ?) DSO's and widefield are not.

[Dartguy]

Someone in the outreach forum recommended this little gadget.

https://www.amazon.c...0?ie=UTF8&psc=1

I just got one in the mail yesterday, but have not tried it out. Nicely made, all metal, and clips firmly onto my Samsung galaxy with a padded clamp. The ring with 3 set screws should be adjustable for most standard 1.25 eyepieces.
It will be my first attempt at "astrophotography". But I'm also curious if it would work well to turn the phone into a vidio viewer.
Should be entertaining !

I ordered on of those on Friday, as well.  Looking forward to it!

[justfred]

Also look into an app called NightCap Pro. Gives you a little more flexibility.

 

Fred

[astrochef]

The Samsung cell phone cameras have some decent manual settings. I'm still experimenting with them but have had some promising results. Definitely not true AP quality stuff but, on a budget, still some fun pics to share with friends and co-workers. My kids enjoy taking them to school to show their friends what they can see with the scopes. The planetary filters come in handy for cutting some of the glare on planets and help the phone avoid some of the "over exposure" glare. It helps to fiddle with the brightness and contrast after in the Photo editor also. I haven't tried stacking multiple images yet but I'm told it will help sharpen the detail even with cell phone pics.

My best Saturn so far from earlier this Summer...

 

 

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[astrochef]

Spent a couple hours on the Moon last night and felt pretty good about this shot of Clavius

 

 

 

 

 

 

Just keep practicing and trying different settings and magnifications. I delete more pics than I save, but the good ones make it worth while, for me anyway

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[Jon Isaacs]

Hi! I'm new to astrophotography and have been reading a lot about using webcams for planetary imaging (prime focus method). This is my question: what are the advantages of using a webcam over a smartphone camera (afocal method)? I understand that resolution isn't important and that frame rate is what matters, so that having a fancy high-res camera doesn't make a difference. But I see most people recommend Microsoft's Lifecam Cinema Webcam, which shoots at 30 fps 720p. Why should I shell out the money for that if I already have a Samsung Galaxy S7, which shoots at 60 fps 1080p? Are there any other advantages to using a webcam other than frame rate? By the way, I have an adapter which allows me to mount the phone to the eyepiece, so stability isn't an issue.

 

Webcams are primarily used for planetary imaging.  The resolution is very important.  The way it works is that a video stream is captured and processed, the images are aligned and then signal processing techniques are applied that reduce the noise and enhance the image.  It is the combining of maybe a thousand images that results in the high resolution images of the planets that webcams produce.

 

For this process, it is important that the video be uncompressed, the processing needs to be done on the raw video rather than the compressed video, the compressed video has a variety of artifacts and issues.  A cell phone is very unlikely to allow the saving of the raw, uncompressed video. 

 

Many years ago, we were using a video camera to record the motion of an electro-polymer.  It was piece of material that would move when excited by electricity.  One day one the graduate students burst into my office, sharing with me that they had found that the electro-polymer moved in steps rather than continuously as had been assumed.  I asked the student if he was using a compressed video format and as I had guessed, sure enough he was.  Uncompressed video taken later showed that the motion was continuous but in an effort to save space, the compression algorithm had decided that it was not necessary to record the slight change of position. 

 

The same sort of thing happens with images, the algorithm decides that a particular detail is insignificant, it is those very details that the signal processing uses to enhance the image.

 

Jon

[Lucas Bittar]

Thank you all for the replies. I took this one today with my S7 and my Zhumell 8 inch Dob!

 

[SeaBee1]

Nice! I have not been able to do that with mine yet... now a question.... did you do any post processing on the image?

 

Best regards!

 

CB

[Lucas Bittar]

Nice! I have not been able to do that with mine yet... now a question.... did you do any post processing on the image?

 

Best regards!

 

CB

Yes, sir! I shot this with the phone (short 30 second clip, for some reason the larger 3 minute one came out much worse), extracted the frames with PIPP, stacked with AutoStakkert and did some adjustments with Photoshop. And I shot it by holding the phone against the eyepiece manually. I think the results will be quite better after I make (or buy) an adapter!

[astrochef]

Great shot of Saturn. I really need to delve into stacking. Keep posting those pics.

[SeaBee1]

 

Nice! I have not been able to do that with mine yet... now a question.... did you do any post processing on the image?

 

Best regards!

 

CB

Yes, sir! I shot this with the phone (short 30 second clip, for some reason the larger 3 minute one came out much worse), extracted the frames with PIPP, stacked with AutoStakkert and did some adjustments with Photoshop. And I shot it by holding the phone against the eyepiece manually. I think the results will be quite better after I make (or buy) an adapter!

 

 

OK, the 3 minute ones came out poorly because of tracking, most likely... I had the same experience, but my trouble even with shorter exposures was the phone camera had trouble with focusing and I AM using an adapter to hold the phone... I am obviously doing something wrong... I'll look into this a bit more. If I can ever get a good shot, I will then hand off to my wife, who is a photographer and an expert with PS.

 

Ah, so much fun with this stuff! Thanks for posting!

 

CB

[Joe Gerardi]

I've gotten two things to get ready to do AP with my Galaxy S5- a cell phone holder for the scope, to set it in place and be able to take longer shots, and a free app called Camera FV-5. In fact, I've removed the original camera app and use FV-5 for everything now.

 

It basically has all the DSLR controls available to you to make the pictures come out better, and even an intervalometer to get time lapse shots.

 

I'm probably going to even buy the full version, something I almost never do with apps.

 

http://www.camerafv5.com/

 

..Joe

[astrochef]

Very cool looking app. I'm eager to hear how it works for you. Hope you'll post some images when you get a chance.

[Lucas Bittar]

a free app called Camera FV-5.

Wow, what a coincidence! I downloaded it yesterday. Haven't tried it yet. I'm going to try to capture a better Saturn this weekend. If I succeed I'll post it here!

[ianstone]

Fv5 gets laggy when try to set resolution or it's just me ?

[astrochef]

Well it's supposed to rain here for the rest of the week so I got out while I could. Set the Z-10 out to cool this morning around 5:00 and took my daughter to swim practice. Came home and pointed the scope at M-42. Just got the Dob in May so it was it's first glimpse of Orion. Decided to clamp on the phone adapter and see how it would do. My focus was a bit off for the camera. (might need to try wearing the reading glasses to check focus on the phone screen next time) And the seeing wasn't all that great this morning but I'm pretty encouraged...

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[Den25]

Someone in the outreach forum recommended this little gadget.

https://www.amazon.c...0?ie=UTF8&psc=1

I just got one in the mail yesterday, but have not tried it out. Nicely made, all metal, and clips firmly onto my Samsung galaxy with a padded clamp. The ring with 3 set screws should be adjustable for most standard 1.25 eyepieces.
It will be my first attempt at "astrophotography". But I'm also curious if it would work well to turn the phone into a vidio viewer.
Should be entertaining !

Thanks! Let me know how it works.  I put it on my wishlist jic

Edited by Den25, 27 September 2016 - 08:43 AM.

[Dartguy]

 

Someone in the outreach forum recommended this little gadget.

https://www.amazon.c...0?ie=UTF8&psc=1

I just got one in the mail yesterday, but have not tried it out. Nicely made, all metal, and clips firmly onto my Samsung galaxy with a padded clamp. The ring with 3 set screws should be adjustable for most standard 1.25 eyepieces.
It will be my first attempt at "astrophotography". But I'm also curious if it would work well to turn the phone into a vidio viewer.
Should be entertaining !

Thanks! Let me know how it works.  I put it on my wishlist jic

 

It isn't great.  My Samsung G6 must be heavy, the clamp isn't strong enough to hold the phone flat, making it necessary to hold the phone with my hand.