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Astrophotography

SLD

Veteran Member
Not sure if others share my passion for astronomy, but on the off chance others do, I thought I’d start a thread of Astrophotography. I’m not that great and don’t have the really expensive equipment necessary for the really great shots but I did this last night. It Messier 65 and 66, and yes I was trying for the entire Leo Triplet, but missed one. That’s OK! This is only 25 subs at 2 minutes a piece with 10 darks and 45 bias shots. Canon T3i modified on an Explore Scientific 127mm scope. ISO 1600. Stacked and processed in ImagesPlus and PSExpress. I need to add flats. Maybe later, chores now.

31315CCC-7D6F-424A-AEE8-FFB6279E18AC.jpeg
 

Treedbear

Veteran Member
That's an incredible image especially taken by a hobbyist. Not that I know anything about the the state of the art these days. I once owned a 8" Celestron reflector, but never got very far with it. So I had to google the scope you use and came upon this guy's website: Astrobin.com and Chuck Ayoub's gallery posting below (sorry for the large size of the image):

WxgPfVGt6JTy_1824x0_cczXV3LN.png

Really amazing that something like that can be attained from someone's backyard in Alabama. Anyway, I'm posting it because what I've always wondered is whether these are true color images and what someone in a spaceship would actually see with the unaided eye. I've been assuming that most of what they show on TV science documentaries is color enhanced to reflect the wavelengths associated with various elements.
 

crazyfingers

Super Moderator
Staff member
That's an incredible image especially taken by a hobbyist. Not that I know anything about the the state of the art these days. I once owned a 8" Celestron reflector, but never got very far with it. So I had to google the scope you use and came upon this guy's website: Astrobin.com and Chuck Ayoub's gallery posting below (sorry for the large size of the image):

View attachment 33434

Really amazing that something like that can be attained from someone's backyard in Alabama. Anyway, I'm posting it because what I've always wondered is whether these are true color images and what someone in a spaceship would actually see with the unaided eye. I've been assuming that most of what they show on TV science documentaries is color enhanced to reflect the wavelengths associated with various elements.

Almost certainly with just an 8" reflector this was taken using a clock drive and perhaps hundreds of individual timed shots stacked and aligned with special software to get the true colors. You just don't see true colors like this just looking through the eyepiece or just one photograph.
 

Shadowy Man

Veteran Member
That's an incredible image especially taken by a hobbyist. Not that I know anything about the the state of the art these days. I once owned a 8" Celestron reflector, but never got very far with it. So I had to google the scope you use and came upon this guy's website: Astrobin.com and Chuck Ayoub's gallery posting below (sorry for the large size of the image):

View attachment 33434

Really amazing that something like that can be attained from someone's backyard in Alabama. Anyway, I'm posting it because what I've always wondered is whether these are true color images and what someone in a spaceship would actually see with the unaided eye. I've been assuming that most of what they show on TV science documentaries is color enhanced to reflect the wavelengths associated with various elements.

Yes, these are quite likely false colors because the dominant color will be red from hydrogen. Also, the surface brightness of these things are pretty low so it won’t look as impressive in person as in a long exposure photograph.
 

crazyfingers

Super Moderator
Staff member
A few years ago I took this photo of the Orion's belt and the Orion nebula using my Canon PowerShot SX50 superzoom at 215mm equivalent. I believe that I used night shot which would have taken several individual photos and stacked them. I took it resting the camera on the roof of the car.

2012 12 30 19 29 06.jpg
 

SLD

Veteran Member
That's an incredible image especially taken by a hobbyist. Not that I know anything about the the state of the art these days. I once owned a 8" Celestron reflector, but never got very far with it. So I had to google the scope you use and came upon this guy's website: Astrobin.com and Chuck Ayoub's gallery posting below (sorry for the large size of the image):

View attachment 33434

Really amazing that something like that can be attained from someone's backyard in Alabama. Anyway, I'm posting it because what I've always wondered is whether these are true color images and what someone in a spaceship would actually see with the unaided eye. I've been assuming that most of what they show on TV science documentaries is color enhanced to reflect the wavelengths associated with various elements.

Yes, these are quite likely false colors because the dominant color will be red from hydrogen. Also, the surface brightness of these things are pretty low so it won’t look as impressive in person as in a long exposure photograph.

The guys on Astrobin can be quite amazing. I have a few pics there myself. Narrowband imaging, like this picture, is very difficult. They typically are taken over several nights, totaling often 60 hours of data. Plus additional dark, bias and flat frames. I only had time for 10 darks last night. I need to add flats. That would eliminate the glow in the middle. Bias shots are easy and I have them prestored. For narrowband, typically people choose the Hubble palette (same filters) so their pictures look like they come from the Hubble telescope itself. Of course those are “false” colors. Almost all colors in space are. If you look at any of these nebulae through a telescope, you won’t see any colors. Just a faint cloud of stuff. If you use an OIII filter to observe though (increases contrast) you’ll notice it turns the nebula green. So not exactly false. H-alpha is near the red end of the spectrum. Hubble makes it almost brown.

One advantage Chuck has over me is a dedicated astronomy camera. He’s using a cooled camera, and the cooling, often 20 degrees Celsius below ambient makes a huge difference in noise. My Canon DSLR actually heats up above ambient so it’s even worse. A real camera is m next big purchase but I need to get better first. They can easily run you over $2K.
 

SLD

Veteran Member
A few years ago I took this photo of the Orion's belt and the Orion nebula using my Canon PowerShot SX50 superzoom at 215mm equivalent. I believe that I used night shot which would have taken several individual photos and stacked them. I took it resting the camera on the roof of the car.

View attachment 33438

There’s some inexpensive mounts for wide field like this. A friend has something called a move shoot move rotator. I think it’s only a few hundred dollars. He takes amazing wide field shots with it. Utterly mind blowing. I’ve enjoyed a bit of wide field but it’s best under far less polluted skies than I am near.
 

Shadowy Man

Veteran Member
Back in my professionally active days, I got the chance to observe with the 0.9m telescope on Kitt Peak, just outside of Tucson, Arizona. I observed a few nebulae, including M27 (aka Dumbbell Nebula) and IC 63. I took narrowband images in lines of hydrogen, sulfur and oxygen. The three individual images are shown below and then the composite three-color, where I colored them red, green, and blue, respectively. I arbitrarily adjusted the brightness of each image to make for a nice color balance, which is why the stars ended up looking yellow/green.

m27_rgb.jpg

m27.jpg

And the below is how the combined image ended up looking for IC 63, a nebula illuminated by Gamma Cassiopeiae.

ic63_lin.jpg
 

Jimmy Higgins

Contributor
This is on the to-do list. We (8-yo daughter and I) recently got an 8-inch'er with EQ mount. She is really into it. The tracking mount makes things so much easier to keep an 8-yo's head in the game. Finally got Jupiter done, early morning thing, and my daughter leapt out of bed when I told her the scope was targeted on it. So she has seen Mars (crappy underwater quality, but big), Jupiter (washed out, turn good), Saturn (pretty good), and Uranus. We had gotten the scope just before the conjunction (took two months to get!), but it was cloudy skies for literally one month straight! :(

Need to get the adapter to get the camera on it. I think I also need to get a north star tool for alignment. I think our equipment, including camera (Sony, which is good with low light) is the minimum required, so the shots should be adequate, nothing great. My Uncle is a "pro", well, "pro-amateur". He did this stuff back in the 80s when you really needed to know your stuff. He now how a pole mounted into the ground for a "tripod", and can take ridiculously long exposures, half-hour plus! He was sent me some mind blowing stuff.
 

SLD

Veteran Member
This is on the to-do list. We (8-yo daughter and I) recently got an 8-inch'er with EQ mount. She is really into it. The tracking mount makes things so much easier to keep an 8-yo's head in the game. Finally got Jupiter done, early morning thing, and my daughter leapt out of bed when I told her the scope was targeted on it. So she has seen Mars (crappy underwater quality, but big), Jupiter (washed out, turn good), Saturn (pretty good), and Uranus. We had gotten the scope just before the conjunction (took two months to get!), but it was cloudy skies for literally one month straight! :(

Need to get the adapter to get the camera on it. I think I also need to get a north star tool for alignment. I think our equipment, including camera (Sony, which is good with low light) is the minimum required, so the shots should be adequate, nothing great. My Uncle is a "pro", well, "pro-amateur". He did this stuff back in the 80s when you really needed to know your stuff. He now how a pole mounted into the ground for a "tripod", and can take ridiculously long exposures, half-hour plus! He was sent me some mind blowing stuff.

Polar alignment is essential for good tracking. It takes me a good hour to get a proper alignment. Often have to redo it several times. Get a good guidescope and a guide camera. Then you need PhD guiding, which is a free software. Once you have that up and running you can 3 minute shots. No more than that usually. Don’t forget darks, flats and bias shots. Still need a better way to do flats. I’m missing them above and it shows.

You can do planetary imaging without it.
 

Jimmy Higgins

Contributor
Looked it up, and apparently the mount I have actually has a place for a polar alignment scope, it is well hidden. So I order that up, a t-mount adapter, and a bulb clicker for the camera, etc... and will see how this works out. With that bulb clicker (for whatever reason Sony made the older one obsolete), I'm going to need to do some waterfall stuff with the ND filter.

But astro first, it'll be tricky with leaves. Out. Hopefully the Sisters are farther along their path and clear. I think the Orion Nebula is blocked for a while. I'll need to check the moon rising and setting.
 

SLD

Veteran Member
Looked it up, and apparently the mount I have actually has a place for a polar alignment scope, it is well hidden. So I order that up, a t-mount adapter, and a bulb clicker for the camera, etc... and will see how this works out. With that bulb clicker (for whatever reason Sony made the older one obsolete), I'm going to need to do some waterfall stuff with the ND filter.

But astro first, it'll be tricky with leaves. Out. Hopefully the Sisters are farther along their path and clear. I think the Orion Nebula is blocked for a while. I'll need to check the moon rising and setting.

There’s plenty of good apps for planning. I like Orion sky safari, but it’s about $16. Stellarium is free and also great. There’s also a free polar alignment app that I find helpful.

Orion is great for photography because it’s so bright. You only need 30 second shots of it to get a good overall photo. More than that and you blow out the trapezium. But it won’t be back until the fall. But summer Galaxy shots are great. There are lots of bright nebulas you can capture. M20, M8, M16. To go beyond 30 seconds you’ll need a guidescope and guide camera. Used ones are easily found and fairly cheap. Mine were actually free, given to me by others who were upgrading. Download PhD guiding as it’s a free app. Also download ImagesPlus a free Astrophotography software. You’ll need to watch a YouTube video about it first to understand what to do. But it’s a real good processing program specifically designed for Astrophotography.

The moon’s up for the next couple of weeks, but contact me off line when you’re going up and I’d be happy to help. And here’s my Orion done about a year and a half ago.

602D5CF3-D12E-4213-A99D-BD81AE72EC4C.jpeg
 

Jimmy Higgins

Contributor
That is incredible.

Received the stuff yesterday. Had to go out and get a metric set of hex wrenches. *YAK!* (Thank goodness I had a Hex wrench < 1/16", otherwise I would have got that first... and then realized I needed metric). But the polar scope is aligned with the mount.

T-mount adapter fits the camera. So seem to have the pieces. We'll see how things are tonight. Start with the moon.
 

Jimmy Higgins

Contributor
Here is a question, is film better than digital? IE, it is possible to use a film camera and stack photos onto a single frame, without using any computers. I get that noise can become an issue, but if you stack short frames, does that mitigate that problem? Obviously, this would be for Deep Space stuff. I'm not clear on when noise becomes a problem, ie, whether it is simply an aggregate thing or a length of exposure thing.
 

Shadowy Man

Veteran Member
Here is a question, is film better than digital? IE, it is possible to use a film camera and stack photos onto a single frame, without using any computers. I get that noise can become an issue, but if you stack short frames, does that mitigate that problem? Obviously, this would be for Deep Space stuff. I'm not clear on when noise becomes a problem, ie, whether it is simply an aggregate thing or a length of exposure thing.
All professional astronomy is done with digital detectors now so I don’t feel that film could be superior. I’m not sure how you’d stack film photographs.

Noise comes in a few flavors, but if the noise is random then stacking more images will help. If it is systematic noise then it won’t help. Longer exposures may be preferred when read noise is high, but shorter exposures can help in other ways.
 

Jimmy Higgins

Contributor
Here is a question, is film better than digital? IE, it is possible to use a film camera and stack photos onto a single frame, without using any computers. I get that noise can become an issue, but if you stack short frames, does that mitigate that problem? Obviously, this would be for Deep Space stuff. I'm not clear on when noise becomes a problem, ie, whether it is simply an aggregate thing or a length of exposure thing.
All professional astronomy is done with digital detectors now so I don’t feel that film could be superior. I’m not sure how you’d stack film photographs.
Some film cameras allow you to not advance the film, so you can take multiple images on a single frame. For normal photography, you could take 4 shots of a length that is 1/4th that required for a proper exposure so the aggregate length is still the same. I did this to get a ghost effect of people on a boardwalk.

4004957558_50fb2a29d6_c.jpg

Noise comes in a few flavors, but if the noise is random then stacking more images will help. If it is systematic noise then it won’t help. Longer exposures may be preferred when read noise is high, but shorter exposures can help in other ways.
I figure people aren't stacking for the fun of it and it makes things work better.
 

Loren Pechtel

Super Moderator
Staff member
Here is a question, is film better than digital? IE, it is possible to use a film camera and stack photos onto a single frame, without using any computers. I get that noise can become an issue, but if you stack short frames, does that mitigate that problem? Obviously, this would be for Deep Space stuff. I'm not clear on when noise becomes a problem, ie, whether it is simply an aggregate thing or a length of exposure thing.

Some film cameras allow you to not advance the film, so you can take multiple images on a single frame. For normal photography, you could take 4 shots of a length that is 1/4th that required for a proper exposure so the aggregate length is still the same. I did this to get a ghost effect of people on a boardwalk.

View attachment 33632

Noise comes in a few flavors, but if the noise is random then stacking more images will help. If it is systematic noise then it won’t help. Longer exposures may be preferred when read noise is high, but shorter exposures can help in other ways.
I figure people aren't stacking for the fun of it and it makes things work better.

Stacking is used to help eliminate noise and to avoid having to track the stars. Multi-exposing film would get rid of both of these benefits. If you are using film mount your camera on a mount that tracks and simply leave the shutter open as long as your exposure calls for.
 

Shadowy Man

Veteran Member
Some film cameras allow you to not advance the film, so you can take multiple images on a single frame. For normal photography, you could take 4 shots of a length that is 1/4th that required for a proper exposure so the aggregate length is still the same. I did this to get a ghost effect of people on a boardwalk.

Sure, but since you’re still using the same piece of film you haven’t gained anything in terms of dynamic range. So, how would this be any different than a long exposure? I guess if you’re not tracking an astronomical object and you need to adjust pointing so as to not smear out an image as a longer exposure would do. But if you are interested in deep space photography that requires long exposures you better be tracking.
 

crazyfingers

Super Moderator
Staff member
I could be completely wrong but I thought that one of the points to stacking multiple images was that real objects like star will be consistent but noise totally random and so easy to filter out in processing.
 

Shadowy Man

Veteran Member
I could be completely wrong but I thought that one of the points to stacking multiple images was that real objects like star will be consistent but noise totally random and so easy to filter out in processing.

Yes. That makes sense with digital imagery. But I am trying to understand why you’d take four separate exposures on one piece of film using 1/4th of the total needed exposure time, as Jimmy said, and expect that to be different than one exposure of the total time. I gave one possible option but I don’t know any others.
 

Loren Pechtel

Super Moderator
Staff member
I could be completely wrong but I thought that one of the points to stacking multiple images was that real objects like star will be consistent but noise totally random and so easy to filter out in processing.

Yes. That makes sense with digital imagery. But I am trying to understand why you’d take four separate exposures on one piece of film using 1/4th of the total needed exposure time, as Jimmy said, and expect that to be different than one exposure of the total time. I gave one possible option but I don’t know any others.

There would be no reason to.

Multiple exposures with film are done to combine different images, not for stacking.
 

Jimmy Higgins

Contributor
Well, need to get extension tube for the telescope adapter. I'm just a bit short of out of focus. Battery also dead in camera, so I needed to charge it a little to test. Glad I did and didn't give up. I was able to get focus on the moon, but by holding the adapter outside the eyepiece area. I hate being stupid with the scope. Get the scope out, trying to polar align, it isn't there. It should occur to me that I haven't leveled the damn mount! But no, that'll take 5 to 10 minutes to remember.
I could be completely wrong but I thought that one of the points to stacking multiple images was that real objects like star will be consistent but noise totally random and so easy to filter out in processing.

Yes. That makes sense with digital imagery. But I am trying to understand why you’d take four separate exposures on one piece of film using 1/4th of the total needed exposure time, as Jimmy said, and expect that to be different than one exposure of the total time. I gave one possible option but I don’t know any others.
And for the record, I was throwing it out there and asking, not claiming it.
 

Treedbear

Veteran Member
I could be completely wrong but I thought that one of the points to stacking multiple images was that real objects like star will be consistent but noise totally random and so easy to filter out in processing.

Yes. That makes sense with digital imagery. But I am trying to understand why you’d take four separate exposures on one piece of film using 1/4th of the total needed exposure time, as Jimmy said, and expect that to be different than one exposure of the total time. I gave one possible option but I don’t know any others.

There would be no reason to.

Multiple exposures with film are done to combine different images, not for stacking.

I'm totally guessing but maybe four separate exposures allows you to take full advantage of the film's or camera's dynamic range. Then the digitized data can be summed to obtain 4 times the sensitivity. Also, I'm not sure about film but with digital cameras I think random noise doesn't just contribute "background" noise but also contributes to the saturation of useful data points and therefore degrades the dynamic range over longer exposures. On the downside, for digital cameras readout noise will increase with increasing number of frames.
 
Last edited:

Loren Pechtel

Super Moderator
Staff member
There would be no reason to.

Multiple exposures with film are done to combine different images, not for stacking.

I'm totally guessing but maybe four separate exposures allows you to take full advantage of the film's or camera's dynamic range. Then the digitized data can be summed to obtain 4 times the sensitivity. Also, I'm not sure about film but with digital cameras I think random noise doesn't just contribute "background" noise but also contributes to the saturation of useful data points and therefore degrades the dynamic range over longer exposures. On the downside, for digital cameras readout noise will increase with increasing number of frames.

With a digital camera you take multiple shots without tracking the stars--each exposure will be in a slightly different position on the sensor. You align the images when stacking. The pixels representing the stars reinforce each other but the noise pixels do not.
 

Jimmy Higgins

Contributor
Starting slow. I really need something to make the focus easier on the scope. Here is a picture of a large rock I saw orbiting the Earth. Also, officially I hate mosquitos. ;)

DSC01031 (002).jpg
 

Jimmy Higgins

Contributor
Nice. I just found this article on low light ISO and sometimes where the noise comes from. I'm just programmed to use ISO 100, but with low light (or maybe longer exposure is more appropriate?) it is using too big a sieve.
 

Shadowy Man

Veteran Member
Here's a daytime shot of the crescent Moon with Venus to the left of it. I had spotted Venus in the morning and noted its relative position to the Moon. That's how I was able to find it later in the day -- this photo was taken at about 12:45 my time. Tamrom AF 70-300mm lens at full zoom, ISO 100, F/7.1, and 1/500th second exposure.

10757725696_IMG_9517b.jpg

I like how you can see how much greater the surface brightness of Venus is than the crescent Moon.
 

crazyfingers

Super Moderator
Staff member
I don't know that I've ever tried Saturn with the camera. To try I'd have to look up where it is these days. For Jupiter I can tell that it's a disc and can see that there are moons. My guess is that Saturn might show that rings exist depending on the angle. Moons would look like stars. There would not likely be any colors.

It looks like Saturn can be seen in the early evening by the end of this year from where I am in the northern hemisphere. However it's on the other side of the sun at the moment so it would not appear as large as it would if it was on our side of the sun. Not sure what difference the distance would really make. But it will be another 15 years roughly before it's on our side of the sun. So worth a try come fall into winter this year.

I think that I looked at it back when I first got my Meade 6" reflector telescope. That was over 20 years ago. If I am recalling correctly it was a white oblong smudge.
 

barbos

Contributor
I don't know that I've ever tried Saturn with the camera. To try I'd have to look up where it is these days. For Jupiter I can tell that it's a disc and can see that there are moons. My guess is that Saturn might show that rings exist depending on the angle. Moons would look like stars. There would not likely be any colors.

It looks like Saturn can be seen in the early evening by the end of this year from where I am in the northern hemisphere. However it's on the other side of the sun at the moment so it would not appear as large as it would if it was on our side of the sun. Not sure what difference the distance would really make. But it will be another 15 years roughly before it's on our side of the sun. So worth a try come fall into winter this year.

I think that I looked at it back when I first got my Meade 6" reflector telescope. That was over 20 years ago. If I am recalling correctly it was a white oblong smudge.

It's visible most of the time of the year and there is no need to wait for 15 years to get close to it. it happens every year and the difference is not that large,.

https://stellarium-web.org/

find it there and take the picture. It says closest approach will be around July 4 - 8.94 a.u.
And farthest 10.9 a.u. around February 4.
 

Shadowy Man

Veteran Member
Saturn is about 10 AU from the Sun so it should vary from about 9-11 AU from Earth.

Wikipedia says the angular size of the disk will range from about 15-20 arcseconds, with the rings being almost double that across - actually wider than Jupiter’s disk.
 

steve_bank

Contributor
What are all those dots? Camera noise?

Hard to imagine a 10 inch scope with a video camera is far better than astronomers had to work with.

I was never eally into it but I went to Stelaphane in Vt in the 80s and heard Dobson speak.

He made mirrors out of scrap Navy port hole glass and gave scopes away around SF.
 

barbos

Contributor
Saturn is about 10 AU from the Sun so it should vary from about 9-11 AU from Earth.

Wikipedia says the angular size of the disk will range from about 15-20 arcseconds, with the rings being almost double that across - actually wider than Jupiter’s disk.
Well, with 1" lens of typical long zoom camera I expect Saturn to be 2 pixels wide and rings twice of that. Just wonder if it can really be resolved as something other than a point object.
 

crazyfingers

Super Moderator
Staff member
Saturn is about 10 AU from the Sun so it should vary from about 9-11 AU from Earth.

Wikipedia says the angular size of the disk will range from about 15-20 arcseconds, with the rings being almost double that across - actually wider than Jupiter’s disk.
Well, with 1" lens of typical long zoom camera I expect Saturn to be 2 pixels wide and rings twice of that. Just wonder if it can really be resolved as something other than a point object.

This is a photo I took of Jupiter with the same camera I used for the moon above. Jupiter is definitely not a point object. If Saturn's rings are at an angle, I'm pretty sure that the camera would be able to show that the rings exist but as I mentioned, probably no colors. The camera is one of those superzooms. It has a small point and shoot sensor but a very long zoom. In the case of this photo, 204 mm. The camera can zoom farther. I expect that when I took this in 2012 that I backed off the zoom to get the moons in.

I don't recall how much care I took taking this or if the camera was in single shot mode or night shot which takes multiple shots and stacks them. The camera could probably do a bit better if I didn't take this hand held which I believe that I did.

2012 12 30 18 46 25.jpg
 

Jimmy Higgins

Contributor
I don't know that I've ever tried Saturn with the camera. To try I'd have to look up where it is these days. For Jupiter I can tell that it's a disc and can see that there are moons. My guess is that Saturn might show that rings exist depending on the angle. Moons would look like stars. There would not likely be any colors.

It looks like Saturn can be seen in the early evening by the end of this year from where I am in the northern hemisphere. However it's on the other side of the sun at the moment so it would not appear as large as it would if it was on our side of the sun. Not sure what difference the distance would really make. But it will be another 15 years roughly before it's on our side of the sun. So worth a try come fall into winter this year.

I think that I looked at it back when I first got my Meade 6" reflector telescope. That was over 20 years ago. If I am recalling correctly it was a white oblong smudge.

It's visible most of the time of the year and there is no need to wait for 15 years to get close to it. it happens every year and the difference is not that large,.

https://stellarium-web.org/

find it there and take the picture. It says closest approach will be around July 4 - 8.94 a.u.
And farthest 10.9 a.u. around February 4.
Looks like the minimum size if about 15 arc seconds and largest is 20 arc seconds for Saturn. Of course, Saturn is always worth looking at.
 

Jimmy Higgins

Contributor
Saturn is about 10 AU from the Sun so it should vary from about 9-11 AU from Earth.

Wikipedia says the angular size of the disk will range from about 15-20 arcseconds, with the rings being almost double that across - actually wider than Jupiter’s disk.
Well, with 1" lens of typical long zoom camera I expect Saturn to be 2 pixels wide and rings twice of that. Just wonder if it can really be resolved as something other than a point object.

This is a photo I took of Jupiter with the same camera I used for the moon above. Jupiter is definitely not a point object. If Saturn's rings are at an angle, I'm pretty sure that the camera would be able to show that the rings exist but as I mentioned, probably no colors. The camera is one of those superzooms. It has a small point and shoot sensor but a very long zoom. In the case of this photo, 204 mm. The camera can zoom farther. I expect that when I took this in 2012 that I backed off the zoom to get the moons in.

I don't recall how much care I took taking this or if the camera was in single shot mode or night shot which takes multiple shots and stacks them. The camera could probably do a bit better if I didn't take this hand held which I believe that I did.

View attachment 33857
Saturn is definitely smaller than Jupiter. Controlling the shutter length would be critical to keep it from overexposing.
 

crazyfingers

Super Moderator
Staff member
Ya Saturn will be smaller though if the rings are at a good angle I should be able to tell that they exist. That's really all I'd expect.

I'm sure that I didn't mess with my metering exposure ISO, etc setting for the jupiter picture. I would have used my custom setting to capture a bird in a bush. Focus and metering set on spot center and let the camera choose what it thinks is best. I'd need to do some serious fiddling for astronomy photos.

And if the camera was on night shot, that's mainly for taking photos of a city skyline at night. Surely not the best for astronomy.

But the lens and sensor should be good enough to take better astronomy photos if the settings provided that flexibility. It's still just a point and shoot camera with a huge zoom.
 

SLD

Veteran Member
Planetary imaging can be very difficult because they have a small angular size, but are very bright. The best way to do them is to set the camera for a high speed, typically 1/100, but do video for 10 minutes. That’s 60,000 frames. There are programs that delace your frames and throw out those that have been distorted by the atmosphere. The rest are stacked and processed.
 

barbos

Contributor
Planetary imaging can be very difficult because they have a small angular size, but are very bright. The best way to do them is to set the camera for a high speed, typically 1/100, but do video for 10 minutes. That’s 60,000 frames. There are programs that delace your frames and throw out those that have been distorted by the atmosphere. The rest are stacked and processed.
ordinary cameras don't have big enough lenses for atmosphere to be a problem. Unless you take pictures during day time over Mojave desert.
 

barbos

Contributor
Saturn is about 10 AU from the Sun so it should vary from about 9-11 AU from Earth.

Wikipedia says the angular size of the disk will range from about 15-20 arcseconds, with the rings being almost double that across - actually wider than Jupiter’s disk.
Well, with 1" lens of typical long zoom camera I expect Saturn to be 2 pixels wide and rings twice of that. Just wonder if it can really be resolved as something other than a point object.

This is a photo I took of Jupiter with the same camera I used for the moon above. Jupiter is definitely not a point object. If Saturn's rings are at an angle, I'm pretty sure that the camera would be able to show that the rings exist but as I mentioned, probably no colors. The camera is one of those superzooms. It has a small point and shoot sensor but a very long zoom. In the case of this photo, 204 mm. The camera can zoom farther. I expect that when I took this in 2012 that I backed off the zoom to get the moons in.

I don't recall how much care I took taking this or if the camera was in single shot mode or night shot which takes multiple shots and stacks them. The camera could probably do a bit better if I didn't take this hand held which I believe that I did.

View attachment 33857
That's better than I expected. Saturn's rings have roughly the same angular size as Jupiter. So I suspect Saturn can be seen as a planet with rings.
So take a picture of Saturn. And use maximum aperture and different setting for exposure (exposure priority)
By the way what is the aperture of your camera? (diameter of the lens)
 

Jimmy Higgins

Contributor
And if the camera was on night shot, that's mainly for taking photos of a city skyline at night. Surely not the best for astronomy.
Not certain, but the night-time will raise the ISO, which from what I read is what you want to do anyway. So ISO 800 or 1600, as there will be signal noise at lower ISOs. Obviously, the other issue would be a tripod if available. That'll help, unless you have surgeon hands, with the super zoom, the camera needs to be super still. The aperture will likely be as wide open as it can for nighttime mode.

If you can't do shutter priority or aperture priority to limit the shutter, it could become hard to resolve Saturn in the final image.
 

crazyfingers

Super Moderator
Staff member
This is a photo I took of Jupiter with the same camera I used for the moon above. Jupiter is definitely not a point object. If Saturn's rings are at an angle, I'm pretty sure that the camera would be able to show that the rings exist but as I mentioned, probably no colors. The camera is one of those superzooms. It has a small point and shoot sensor but a very long zoom. In the case of this photo, 204 mm. The camera can zoom farther. I expect that when I took this in 2012 that I backed off the zoom to get the moons in.

I don't recall how much care I took taking this or if the camera was in single shot mode or night shot which takes multiple shots and stacks them. The camera could probably do a bit better if I didn't take this hand held which I believe that I did.

View attachment 33857
That's better than I expected. Saturn's rings have roughly the same angular size as Jupiter. So I suspect Saturn can be seen as a planet with rings.
So take a picture of Saturn. And use maximum aperture and different setting for exposure (exposure priority)
By the way what is the aperture of your camera? (diameter of the lens)

The diameter of the lens glass is about an inch and a half. I am able to set for Av Aperture priority. Tv, etc.. there are a lot of sittings. Before Saturn comes up at a reasonable time in the fall I will try to figure it out.

My newer camera, also a superzoom, the Canon PowerShot SX70, which I'm still getting used to, has about a 1.7 inch lens. It has all the various setting that the older one has.
 

crazyfingers

Super Moderator
Staff member
And if the camera was on night shot, that's mainly for taking photos of a city skyline at night. Surely not the best for astronomy.
Not certain, but the night-time will raise the ISO, which from what I read is what you want to do anyway. So ISO 800 or 1600, as there will be signal noise at lower ISOs. Obviously, the other issue would be a tripod if available. That'll help, unless you have surgeon hands, with the super zoom, the camera needs to be super still. The aperture will likely be as wide open as it can for nighttime mode.

If you can't do shutter priority or aperture priority to limit the shutter, it could become hard to resolve Saturn in the final image.

The camera does have Av and Tv modes though I don't know if I have those controls and others are available under Night Shot. As I mentioned, night shot takes several shots and stacks them. I am not sure yet, before really studying the manual, what controls I have under that special scene mode. I expect not as many. Even metering. Under my usual uses I can set metering for evaluative ( the entire field of view) center weight or spot. Since most of my photos are of birds in a bush or similar, I have the metering set on center spot, along with focus. Lots of studying and lots of experimentation is needed to really set this for astronomy.

I do have a tripod. I can at least set it and set the timer and let it shoot hands free.
 

barbos

Contributor
And if the camera was on night shot, that's mainly for taking photos of a city skyline at night. Surely not the best for astronomy.
Not certain, but the night-time will raise the ISO, which from what I read is what you want to do anyway. So ISO 800 or 1600, as there will be signal noise at lower ISOs. Obviously, the other issue would be a tripod if available. That'll help, unless you have surgeon hands, with the super zoom, the camera needs to be super still. The aperture will likely be as wide open as it can for nighttime mode.

If you can't do shutter priority or aperture priority to limit the shutter, it could become hard to resolve Saturn in the final image.

The camera does have Av and Tv modes though I don't know if I have those controls and others are available under Night Shot. As I mentioned, night shot takes several shots and stacks them. I am not sure yet, before really studying the manual, what controls I have under that special scene mode. I expect not as many. Even metering. Under my usual uses I can set metering for evaluative ( the entire field of view) center weight or spot. Since most of my photos are of birds in a bush or similar, I have the metering set on center spot, along with focus. Lots of studying and lots of experimentation is needed to really set this for astronomy.

I do have a tripod. I can at least set it and set the timer and let it shoot hands free.

in your place the best time for taking pictures is just before sunrise. Now Saturn is slightly to the right of Jupiter and actually higher - 23 degrees over horizon.

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1.7*1.22*58232*2./(150e6*9.44)/(0.6e-6/0.0254) = 7.22137115630885 pixels resolution
for Saturn itself on 1.7" lens
 

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