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07/12/2014 12:10:31 PM · #151
the "moon illusion" has been a topic of discussions in many forms over time, what ever the cause the camera and the human eye see 2 different things

this is another example of the "moon illusion". the red/orange colored moon was taken when it was just slightly above the horizon, you can see the mirage/reflection of the red portion below the full disc, the lighter color was taken a few hours later when the moon was much higher above the horizon.

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the reason I posted this was to see if people could go out and do this for themselves just as something to do for giggles.
07/12/2014 12:22:07 PM · #152
The moon is actually 1.5% larger when directly overhead because it's about 3,900 miles closer. If you look straight up at the moon, the distance is directly from your eyes to the lunar surface, but if you look at the moon on the horizon you're looking across the radius of the earth plus the distance to the moon.
07/12/2014 04:49:57 PM · #153
Originally posted by scalvert:

The moon is actually 1.5% larger when directly overhead because it's about 3,900 miles closer. If you look straight up at the moon, the distance is directly from your eyes to the lunar surface, but if you look at the moon on the horizon you're looking across the radius of the earth plus the distance to the moon.


I thought about this as well. Perhaps this is what jab's camera caught, but I'd have to ask him if the bigger image was the one high in the sky?
07/14/2014 08:26:38 PM · #154
Originally posted by DrAchoo:

Originally posted by scalvert:

The moon is actually 1.5% larger when directly overhead because it's about 3,900 miles closer. If you look straight up at the moon, the distance is directly from your eyes to the lunar surface, but if you look at the moon on the horizon you're looking across the radius of the earth plus the distance to the moon.


I thought about this as well. Perhaps this is what jab's camera caught, but I'd have to ask him if the bigger image was the one high in the sky?


From the both the description and the image, it would seem so. Amazing the amount of distortion in the "near the horizon" image!
07/14/2014 10:44:44 PM · #155
Anyone familiar with deep space objects and techniques? I have a Nexstar 5SE that tracks but I just can't figure out the next step no pun intended. I hear people combining multiple shots to get nebulas and such, but no one quite tells you the just of it. Thanks
07/15/2014 12:15:37 AM · #156
Originally posted by coronamv:

Anyone familiar with deep space objects and techniques? I have a Nexstar 5SE that tracks but I just can't figure out the next step no pun intended. I hear people combining multiple shots to get nebulas and such, but no one quite tells you the just of it. Thanks


easily the most difficult thing to do in all of photography.
07/15/2014 12:16:44 AM · #157
There is a (free) program called Registax which is designed for stacking astronomical photos, I presume for contrast/exposure enhancement and noise-reduction. Haven't used it but I know it's been around for a long time ...
07/15/2014 12:49:03 AM · #158
Originally posted by coronamv:

Anyone familiar with deep space objects and techniques? I have a Nexstar 5SE that tracks but I just can't figure out the next step no pun intended. I hear people combining multiple shots to get nebulas and such, but no one quite tells you the just of it. Thanks


i tried this for a few years and was never really successful at it. The key item to have is a very sturdy tripod and very good Equatorial mount that tracks very accurately, which means lots of money ($1,000+ range). yes you can use a cheap EQ mount, but you will be limited on exposure length, unless you are willing to dedicate a lot of trial and error time to getting a low cost rig to work. The telescope is not that big of a deal unless you are going to get VERY serious in astrophotography.
I have officially given up on that. Im sticking to the moon or just wide angle stuff like night scapes.

The Nexstar mount is an ALT/AZ mount and is really only good for the moon and planets for photography. you could do deep sky with it, but your limited on the exposure and then you would have to de-rotate the images so they all line up before you stack them
you will need to take many images with the same settings, then a few with faster shutter speeds to get a dark background. Your looking at images of up to several minutes each, or several hundred shorter exposures.

basically in a nut shell, using several images stacked together to get a final clear image is reducing the signal to noise ratio, which brings out more detail and reduces the noise. You simply can not use the same image over and over. you need multiple individual exposures with several different groups at different ISO and shutter speeds
for it to work.

07/15/2014 12:54:21 AM · #159
Thanks Guys now to go find a new mount for my scope and beat my head in the wall.
07/15/2014 09:54:12 AM · #160
Originally posted by coronamv:

Thanks Guys now to go find a new mount for my scope and beat my head in the wall.


this is one area that you should really research extensively before you buy anything. Also look for one that has an Auto Guider port. Using an Auto Guider will allow for much longer exposures. You may not need to use that now, but after you get up and running and get things worked out, then you might want to expand into using an auto guider to get some longer exposures.

if at all possible, try to meet up with a local astronomy club on one of their viewing nights so you can get a first hand look at some setups and ask questions.
07/15/2014 10:36:32 AM · #161
Excellent advice ' . substr('//www.dpchallenge.com/images/user_icon/21.gif', strrpos('//www.dpchallenge.com/images/user_icon/21.gif', '/') + 1) . ' jab119.
It's a very technical road to travel, and is loaded with all kinds of interesting hardware that should be carefully researched before making purchases.
Meanwhile, the Moon and Saturn are good at this time, and you have the gear now to shoot those.
You might look at a point n' shoot bracket for digiscope shooting. With the point n' shoot, you can get much more magnification for bright objects than with a DSLR with it's larger sensor coupled directly to the telescope.
One other simple suggestion is that mirror lockup helps a lot with vibration when telescope shooting with the DSLR.
07/15/2014 10:59:35 AM · #162
Originally posted by jab119:

this is one area that you should really research extensively before you buy anything.


Originally posted by melonmusketeer:

It's a very technical road to travel...


Agreed wholeheartedly on both counts!
One thing to keep in mind... for deep sky astrophotography, high magnification is not always necessary or even desirable. As magnification increases, the challenges with accurate tracking go up dramatically, and so the cost of the equipment needed goes up dramatically as well. Low-magnification (think 24mm to 100mm) is a good place to start and hone your skills, then move up to higher magnification gradually and improve your technique and equipment as you need to, and once you understand exactly what improvements are required.
Right now your biggest deficit is your lack of an equatorial mount. One way around this is to buy a basic used mount, but you really need to do your research before jumping into that. Another way might be to look into the AstroTrac. The AstroTrac is intended for low-mass loads, but can easily handle a DSLR and moderately-sized lens. Tracking is better than a lot of mounts that cost many times more. What you give up is the ability to carry large loads, and tracking is limited to a couple hours (more than enough for all but the die-hards).
07/15/2014 12:08:16 PM · #163
Originally posted by kirbic:

Originally posted by jab119:

this is one area that you should really research extensively before you buy anything.


One way around this is to buy a basic used mount, but you really need to do your research before jumping into that. Another way might be to look into the AstroTrac. The AstroTrac is intended for low-mass loads, but can easily handle a DSLR and moderately-sized lens. Tracking is better than a lot of mounts that cost many times more. What you give up is the ability to carry large loads, and tracking is limited to a couple hours (more than enough for all but the die-hards).


Earlier this year I purchased the iOptron Skytracker

I used it out in Big Bend NP for a few shots. I havent had much time to really put it through its paces, but I was able to get some decent wide field @ 4 minutes
07/15/2014 02:08:20 PM · #164
And yet another option in the (relatively) low-cost realm. As with the others, some accessory equipment, namely a sturdy tripod and two heads are required.
07/15/2014 02:26:06 PM · #165
Originally posted by kirbic:

And yet another option in the (relatively) low-cost realm. As with the others, some accessory equipment, namely a sturdy tripod and two heads are required.


A friend of mine just bought it. If we get it before Thursday we will try it that night :)
07/16/2014 08:23:27 PM · #166
Typhoon Neoguri in Moonlight

Message edited by author 2014-07-16 20:23:52.
07/16/2014 11:11:53 PM · #167
Yeah Many new toys out since I first bought the telescope. Some not to bad some quite expensive. Anyone use a GPS system to setup a scope?
07/16/2014 11:26:00 PM · #168
Originally posted by coronamv:

Yeah Many new toys out since I first bought the telescope. Some not to bad some quite expensive. Anyone use a GPS system to setup a scope?


i am familiar with the Meade GPS system fro years ago. all it does is enter in your current location and time into the hand controller (computer) for alignment. Its great if you take the scope around to many different areas frequently. but if your only going to use it as the house, its kinda pointless as you can set the location once manually and your done, you will just need to enter in the current time each time you set up.

I would not pass up a set up that has GPS with it.
07/17/2014 02:31:29 AM · #169
I did find a fix for my scope dropping due to the weight of the camera. There are two points on the arm that can be tighten to allow for the extra weight. The equatorial mounts are a little out of my price range at the moment. I could move my tube but may be better off waiting and upgrading the whole system later down the line.I was thinking about one of these for now to see if I can get a better lock.
07/17/2014 09:11:18 AM · #170
Originally posted by jab119:

Earlier this year I purchased the iOptron Skytracker

I used it out in Big Bend NP for a few shots. I haven't had much time to really put it through its paces, but I was able to get some decent wide field @ 4 minutes


I also invested in the iOptron Skytracker last year as an alternative to carrying around my full scope rig (8 inch SCT. the whole weighs about 60 lbs) and have been very happy with it.

Grand Teton Milky Way
Teton II

Earlier this month I spent some time on a western road trip and did some shooting for traditional milky way shots in the Cascades:
Cascades I
Cascades II

And a new style of this "terrestrial astro" that I've not done before - lighting the landscape with the light of the moon:
Crater Lake by Moonlight
Moonlight Tetons
Moonlight Tetons II
07/17/2014 09:43:23 AM · #171
Originally posted by coronamv:

I did find a fix for my scope dropping due to the weight of the camera. There are two points on the arm that can be tighten to allow for the extra weight. The equatorial mounts are a little out of my price range at the moment. I could move my tube but may be better off waiting and upgrading the whole system later down the line.I was thinking about one of these for now to see if I can get a better lock.


definitely save up for a good mount
07/17/2014 09:46:28 AM · #172
Originally posted by strangeghost:



I also invested in the iOptron Skytracker last year as an alternative to carrying around my full scope rig (8 inch SCT. the whole weighs about 60 lbs) and have been very happy with it.

Grand Teton Milky Way
Teton II

Earlier this month I spent some time on a western road trip and did some shooting for traditional milky way shots in the Cascades:
Cascades I
Cascades II

And a new style of this "terrestrial astro" that I've not done before - lighting the landscape with the light of the moon:
Crater Lake by Moonlight
Moonlight Tetons
Moonlight Tetons II


Good stuff. Im going to be up in Arches, Tetons and Yellowstone in 4 weeks and plan on having the iOptron with me to do some similar shots.
07/17/2014 09:52:33 AM · #173
Just wanted to share my comet I captured.. what I love about this picture is it shows it near a plane that was flying by.. I was actually trying to practice sky shooting with that plane.. was not expecting to capture that little comet too, let alone see one.. I am having to start to read by this thread from post one and I will catch up :-)) This is a great thread by the way, thank you..

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This was a picture I captured with my point and shoot.

I also love astronomy photography but never really had the equipment to do so.. Now, with the DLSR I really plan on getting some shots when I go out on vacation next month and I am really hoping to get some good skyline pictures..

I plan on using my ISO 100, bulb mode, tripod/remote, F11 or so (I think) and my 70-300 lens..

Message edited by author 2014-07-17 09:54:36.
07/17/2014 11:25:38 AM · #174
Originally posted by jgirl57:

Just wanted to share my comet I captured.. what I love about this picture is it shows it near a plane that was flying by.. I was actually trying to practice sky shooting with that plane.. was not expecting to capture that little comet too, let alone see one.. I am having to start to read by this thread from post one and I will catch up :-)) This is a great thread by the way, thank you..

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This was a picture I captured with my point and shoot.

I also love astronomy photography but never really had the equipment to do so.. Now, with the DLSR I really plan on getting some shots when I go out on vacation next month and I am really hoping to get some good skyline pictures..

I plan on using my ISO 100, bulb mode, tripod/remote, F11 or so (I think) and my 70-300 lens..


which comet is this?
07/17/2014 11:30:54 AM · #175
Im not so sure this is a comet. Your exposure settings would need to be very long to capture a comet, Maybe a meteor (shooting star) would be a better guess, could be a satellite as well
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