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Chat => Photography => Topic started by: Binary Shadow on February 22, 2013, 13:37:46 PM

Title: Astro Photography
Post by: Binary Shadow on February 22, 2013, 13:37:46 PM
After reading Russells thread I thought I would share my experiance.

I to went out to see if I could see the near miss asteroid. Was cold.. and I had nothing but my 7D 100-400mm lens and a tripod.. and I had no chance of seeing it lol.

I took a few snaps anyway: I used the 2 second self timer to try and reduce camera shake when taking the shot, should have broken out the remote really and used shutter lock up, the tripod wasnt as sturdy as it could have been either.

(http://farm9.staticflickr.com/8385/8496865371_8227221eb9_c.jpg) (http://www.flickr.com/photos/12512629@N07/8496865371/)
Moon (http://www.flickr.com/photos/12512629@N07/8496865371/) by Adam Woodford (http://www.flickr.com/people/12512629@N07/), on Flickr

(http://farm9.staticflickr.com/8087/8497968058_37ab675f9a_c.jpg) (http://www.flickr.com/photos/12512629@N07/8497968058/)
Jupiter (http://www.flickr.com/photos/12512629@N07/8497968058/) by Adam Woodford (http://www.flickr.com/people/12512629@N07/), on Flickr

(http://farm9.staticflickr.com/8377/8496863649_d569836511_c.jpg) (http://www.flickr.com/photos/12512629@N07/8496863649/)
Orion's Belt (http://www.flickr.com/photos/12512629@N07/8496863649/) by Adam Woodford (http://www.flickr.com/people/12512629@N07/), on Flickr

(http://farm9.staticflickr.com/8507/8496861821_bbfaf0266e_c.jpg) (http://www.flickr.com/photos/12512629@N07/8496861821/)
Orion's Belt (http://www.flickr.com/photos/12512629@N07/8496861821/) by Adam Woodford (http://www.flickr.com/people/12512629@N07/), on Flickr

I was blown away by what I wasnt seeing.. the naked eye vs even just the 400mm lens, so much I cant see, really fancy a telescope now.

Jupiters moons I believe anyway in shot.
Title: Re: Astro Photography
Post by: Clock'd 0Ne on February 22, 2013, 14:02:06 PM
If I had a decent sized garden I'd love to be able to get outside with a telescope and have a proper look at the sky, the difference is amazing.
Title: Re: Astro Photography
Post by: Eggtastico on February 22, 2013, 14:36:28 PM
i tried a telescope & mount for my camera. was really difficult as when zoomed in that much everything moves really fast.
I even tried hooking it all up to my computer, realised in the end my equipment wasnt up to it. I would love a computerised telescope & not living to far from brecon is handy. Just i know I woudnt have the time to use it & to much light pollution in my back garden

I believe a lot of people remove/replace the IR from the camera sensor to capture more detail.
Title: Re: Astro Photography
Post by: Russell on February 22, 2013, 15:02:02 PM
I went out with pair of binoculars to try and see the asteroid but didn't see it but I'd agree its amazing the amount of stuff you can see with binoculars or a telescope.  With cameras I've found to get the detail out you really need to do a bit of work in Photoshop etc when your editing it to try and get the stars to come out otherwise they just aren't bright enough by themselves without doing a really long exposure.

Looking at your pics it looks like you've boosted the ISO to get the shutter speed down, you might be better putting your ISO on say 200/400 and making your shutter speed a lot longer, you loose detail and dynamic range when you boost your ISO up high.
Title: Re: Astro Photography
Post by: Russell on February 22, 2013, 15:04:14 PM
i tried a telescope & mount for my camera. was really difficult as when zoomed in that much everything moves really fast.
I even tried hooking it all up to my computer, realised in the end my equipment wasnt up to it. I would love a computerised telescope & not living to far from brecon is handy. Just i know I woudnt have the time to use it & to much light pollution in my back garden

I believe a lot of people remove/replace the IR from the camera sensor to capture more detail.

I've got an adaptor so I can attach my camera to a telescope but it takes out the eye pieces which give you most of the magnifictation instead your telescope just becomes a big say 700mm lens, I think most people use webcams attached to the eyepiece to get good results but yeah things move very quickly, you maybe have 10-15 seconds at most whilst watching Jupiter through a telescope so not good for a long exposure shot.
Title: Re: Astro Photography
Post by: Serious on February 22, 2013, 15:44:39 PM
If you live in a built up area a lot of the stars you can't see are unfortunately hidden by light pollution. For proper night sky viewing you need to get away from the security lights, street lights and preferably high up.
Title: Re: Astro Photography
Post by: Eggtastico on February 22, 2013, 16:15:17 PM
i tried a telescope & mount for my camera. was really difficult as when zoomed in that much everything moves really fast.
I even tried hooking it all up to my computer, realised in the end my equipment wasnt up to it. I would love a computerised telescope & not living to far from brecon is handy. Just i know I woudnt have the time to use it & to much light pollution in my back garden

I believe a lot of people remove/replace the IR from the camera sensor to capture more detail.

I've got an adaptor so I can attach my camera to a telescope but it takes out the eye pieces which give you most of the magnifictation instead your telescope just becomes a big say 700mm lens, I think most people use webcams attached to the eyepiece to get good results but yeah things move very quickly, you maybe have 10-15 seconds at most whilst watching Jupiter through a telescope so not good for a long exposure shot.

problem I had with the adapter was Id find something interesting using an eyepiece, then the weight of the camera & adapter when fitting would move the telescope. lot of arsing around & I gave up in the end
Title: Re: Astro Photography
Post by: XEntity on February 22, 2013, 19:26:27 PM
I follow Trey Ratcliff on facebook who is pretty much the god of HDR, if you need to know how to do HDR visit stuck in customs, the other day he uploaded an amazing photo under this category.

http://www.stuckincustoms.com/2013/02/13/the-church-of-the-good-shepherd-under-the-stars/ (http://www.stuckincustoms.com/2013/02/13/the-church-of-the-good-shepherd-under-the-stars/)

Mind blown!
 :o
Title: Re: Astro Photography
Post by: M3ta7h3ad on February 22, 2013, 21:31:43 PM
Take lots and lots of shots. Layer and you'll see lots more.
Title: Re: Astro Photography
Post by: zpyder on February 23, 2013, 09:46:26 AM
When I went to wales last year I took advantage of being in the middle of nowhere one night and took loads of shots. Used the opensource "DeepSkyStacker" program. Didn't have a clue what I was doing, but it did give really good results with not much effort. As M3ta says, stack the shots. I can't remember what the rule of thumb is (if there is one) but I think I was stacking something like 10 shots of 30s each together. I think the idea is that combining the shots brings out the really weak stars, and by using shorter single exposures it compensates for the movement of the earth etc.

If it's clear tonight or tomorrow I might be tempted to head out into the NF or something.
Title: Re: Astro Photography
Post by: Russell on February 23, 2013, 11:44:37 AM
I follow Trey Ratcliff on facebook who is pretty much the god of HDR, if you need to know how to do HDR visit stuck in customs, the other day he uploaded an amazing photo under this category.

http://www.stuckincustoms.com/2013/02/13/the-church-of-the-good-shepherd-under-the-stars/ (http://www.stuckincustoms.com/2013/02/13/the-church-of-the-good-shepherd-under-the-stars/)

Mind blown!
 :o

Oh my!  Saying that however when you look at it full size theres a few bits that are a tad well weird infront of the house, still a great shot though.

Quote
problem I had with the adapter was Id find something interesting using an eyepiece, then the weight of the camera & adapter when fitting would move the telescope. lot of arsing around & I gave up in the end

Think I had the same problem, you really could do with your camera on a tripod itself to hold the weight but then it'd be just about impossible to move around at all so I gave up too  ;D
Title: Re: Astro Photography
Post by: Mongoose on March 20, 2013, 23:04:59 PM
I long ago gave up on trying to use my SLR on a Newtonian, the contrast isn't up to it and as has been observed even the really big ones just end up being a 1000mm F/5 lens. You're better off either using a webcam and stacking or just looking through the thing and marvelling at the wonders of the universe.

For astro photography with an SLR, what you need is refractive optics, and big ones. I have used my 300mm f/2.8 with some success. The other thing you need if you want to get anything other than star trails is an equatorial driven mounting, or a good computer drive with a star tracker. You will also need to be prepared to spend as much time setting your mounting up as you do taking photographs.

I use (or have used in the past, haven't broken it out in much too long) a Celestron equatorial mount which came with a 4.5" Newtonian  telescope. I picked this because it turns out you can get a scope with a single axis driven mount for less than the mount on its own. Go figure. I made some modifications to the mount, basically attached an old air-rifle sight to it, to make it easier to align with the pole star, and at 300mm with careful alignment it's good for a 3 minute exposure. Any more than that and you'll need a computer controlled dual axis drive with a star tracker.

I always think the night sky is worth it though, especially showing it to people who've not seen it before. The only thing more amazing than the planet Saturn is the look on the face of someone who has never seen it before, the first time they look through a big telescope. For some reason, no one is quite prepared for the fact that Saturn looks exactly like you think it does.
Title: Re: Astro Photography
Post by: M3ta7h3ad on March 21, 2013, 00:24:52 AM
There is an interesting YouTube video of a talk at an astronomy symposium from someone who used an SLR, 50mm prime lense and took short exposures to eliminate star trails.

Then used image stacking and post processing not only to remove noise, light  pollution and hot pixels very very effectively but to produce images of the entire messier atlas, a large number of NGC objects and more.

Have a look for astrophotography with an SLR on YouTube.

Sent from my Nexus 4 using Tapatalk 2

Title: Re: Astro Photography
Post by: Mongoose on March 21, 2013, 19:39:15 PM
There is an interesting YouTube video of a talk at an astronomy symposium from someone who used an SLR, 50mm prime lense and took short exposures to eliminate star trails.

Then used image stacking and post processing not only to remove noise, light  pollution and hot pixels very very effectively but to produce images of the entire messier atlas, a large number of NGC objects and more.

Have a look for astrophotography with an SLR on YouTube.

Sent from my Nexus 4 using Tapatalk 2

v interesting, I can see how that could work, I shall go have a look thanks!

Stacking is an extremely powerful technique.
Title: Re: Astro Photography
Post by: Mongoose on March 21, 2013, 20:18:23 PM
M3ta7h3ad, I've just had a look on YouTube and there's a LOT of astro photography vids on there, can't see the wood for the trees if I'm honest. Do you have a link to the one you're talking about? it sounds really interesting.
Title: Re: Astro Photography
Post by: M3ta7h3ad on March 21, 2013, 22:10:33 PM
M3ta7h3ad, I've just had a look on YouTube and there's a LOT of astro photography vids on there, can't see the wood for the trees if I'm honest. Do you have a link to the one you're talking about? it sounds really interesting.

This one: http://youtu.be/11d-JbxXGAA
Title: Re: Astro Photography
Post by: zpyder on July 30, 2013, 13:28:20 PM
I'm off to Wales on Thursday, back early on Sunday. Camping down near St. Davids, so hopefully if the sky is clear, light pollution shouldn't be too bad.

Not sure between going telephoto or wide angle. Will probably do both, using deep sky stacker to stack a mega load of images together. I've worked out my f1.8 40mm would be good for up to 10s exposures, so 100 exposures = 16 minutes. Not much I guess, but it'll be a warm up for going to Yorkshire the week after.

Redundancy is fun!
Title: Re: Astro Photography
Post by: Eggtastico on July 30, 2013, 21:48:43 PM
I recommend the restraunt in porthgain if your out that way.
Porthgain is worth a trip even if your not hungry.
Title: Re: Astro Photography
Post by: Russell on July 30, 2013, 22:18:46 PM
I'm off to Wales on Thursday, back early on Sunday. Camping down near St. Davids, so hopefully if the sky is clear, light pollution shouldn't be too bad.

Not sure between going telephoto or wide angle. Will probably do both, using deep sky stacker to stack a mega load of images together. I've worked out my f1.8 40mm would be good for up to 10s exposures, so 100 exposures = 16 minutes. Not much I guess, but it'll be a warm up for going to Yorkshire the week after.

Redundancy is fun!

Do both but it depends what your after, wide angle is great for getting some foreground interst in or leading lines or something like that, but with telephoto you can concentrate on one particular star cluster or something.  With either from larger the apperture the better so your 40mm will be good if a little bit in the middle focal length wise.

I've never managed to get something stacked with DSS so it'll be interesting to see what you can come up with, I remember watching a video where someone said you do 600/focal length to get the number of seconds before you start to see star trails so you should get 15s but your better off playing around with it when you get there.

Good luck with focusing as well, you don't need the stars 100% in focus for something like a star trails shot but if your not after trails its a bit awkward, live view is your friend but again the larger the aperture the better as it lets more light in, I usually struggle with my 10-20mm at f4 but never tried it on anything better.

Erm can't really think of too much else other than maybe make sure your phones for plenty of charge so you can play around on it whilst you wait around.
Title: Re: Astro Photography
Post by: Mongoose on August 07, 2013, 19:12:34 PM
without a driven mount, it'll be a LOT easier to get deep sky objects with the 40 1.8 than a telephoto. Two reasons for this:

1. wider angle lets you use longer individual exposures

2. f/1.8. I don't know what teles you have available, but that's a good stop faster than the fastest long lens I know of, and 2 or more stops faster than most.

This adds up to a lot more light gathering per frame. This is important because although you'll be using stacking to bring out the faint objects, you still need there to be SOME difference between object and non-object pixels. Exposure stacking is a great tool, but like most post processing it has limitations compared to gathering the photons in one big go.

The Milky Way makes an exciting target for shortish exposures with foreground interest

Pick your targets carefully, some deep sky objects are actually HUGE and you don't really need a telephoto to photograph them. The great nebula in Orion and the Andromeda galaxy leap to mind. Both are larger than the full moon, the Orion nebula quite a lot larger.

You'll also want to consider a dark frame. My camera does dark frame subtraction by default on long exposures, but that doubles the length of acquisition as it captures a second exposure of the same length with the shutter closed. I usually turn this option off and use a separate dark frame taken with the lens cap on. That way I only have to take one per length of exposure/ISO combination I'm using. I assume you're shooting raw, if your usual raw converter doesn't support dark frame subtraction, I have previously used UFRAW for this purpose, and it now appears Rawtherapee also supports it with the latest version, although I haven't tried that yet.

good luck and have fun
Title: Re: Astro Photography
Post by: zpyder on August 07, 2013, 21:27:29 PM
Wales was a blowout due to clouds. Yorkshire tomorrow though for a few days, down by a resevoir, so some good sunset shots, and maybe astro stuff then.

Photos from Wales:

http://www.flickr.com/photos/zpyder/sets/72157634957187426/

(http://farm3.staticflickr.com/2838/9448479231_f8a2561aa5_z.jpg) (http://www.flickr.com/photos/zpyder/9448479231/)
B20.jpg (http://www.flickr.com/photos/zpyder/9448479231/) by Chris_Moody (http://www.flickr.com/people/zpyder/), on Flickr

(http://farm4.staticflickr.com/3819/9451246538_1ea2e622da.jpg) (http://www.flickr.com/photos/zpyder/9451246538/)
Sunset 3.jpg (http://www.flickr.com/photos/zpyder/9451246538/) by Chris_Moody (http://www.flickr.com/people/zpyder/), on Flickr
Title: Re: Astro Photography
Post by: Mongoose on August 07, 2013, 22:50:29 PM
washout for astro  maybe, but the landscapes turned out pretty good, and the clouds make the sky more interesting so not all bad!
Title: Re: Astro Photography
Post by: Russell on August 12, 2013, 13:51:35 PM
Yeah first ones not bad but maybe boost the contrast in the sky to darken it down a bit, make it more moody and at the same time give it a bit of definition between the sky and the ground?

The 2nd one's foreground is good just a shame the suns blown well out, clouds look cool to the left of it though.  Have you done that as HDR?
Title: Re: Astro Photography
Post by: zpyder on August 12, 2013, 20:15:38 PM
HDR + ND Grad. Still learning the ropes with Photoshops "Merge to HDR Pro" tool. I'm thinking the second one would have worked better as two separate HDRs, (sky+sun, and sea and rocks) layered and masked together. I just couldn't seem to get the sky "right" without the sun getting washed out.
Title: Re: Astro Photography
Post by: Russell on August 12, 2013, 20:27:24 PM
HDR + ND Grad. Still learning the ropes with Photoshops "Merge to HDR Pro" tool. I'm thinking the second one would have worked better as two separate HDRs, (sky+sun, and sea and rocks) layered and masked together. I just couldn't seem to get the sky "right" without the sun getting washed out.

Its difficult shooting into the sun, I often try it with some of my shots and they just look a bit wrong at times, in some ways I have no idea how some people manage it tbh, more practice is required me thinks!  But I think if you'd waited around for another 20 mins until the sun had actually set it'd drop in intensity and the DR between the sea and the sky would have lessened to such an extent it wouldn't have blown out.
Title: Re: Astro Photography
Post by: zpyder on August 13, 2013, 09:09:39 AM
Yeah, I hung around for 10-20 minutes until pretty much any colour had disappeared from the sky. On the walk back I realised I'd have been better off photographing away from the sun as the cliffs were still fairly lit up and colourful, oh well!

One thing I'm noticing is that when I've got several HDR shots from the same "set", If I flickr through shot 1, shot 2, shot 3 etc, I think they improve, either due to the light being better, or just the fact that I've progressively tweaked the HDR settings!
Title: Re: Astro Photography
Post by: Russell on August 13, 2013, 21:03:54 PM
Yeah, I hung around for 10-20 minutes until pretty much any colour had disappeared from the sky. On the walk back I realised I'd have been better off photographing away from the sun as the cliffs were still fairly lit up and colourful, oh well!

One thing I'm noticing is that when I've got several HDR shots from the same "set", If I flickr through shot 1, shot 2, shot 3 etc, I think they improve, either due to the light being better, or just the fact that I've progressively tweaked the HDR settings!

I seem to remember some tip I heard years ago before I even got in photography saying you should have the sun over your shoulder, can't remember the anything more than that so could have been for a different aspect of photography but I guess it works to a certain degree.  Thing is most of the colour & contrast is if you shoot in the rough direction of the sun or at least in the same 180 degrees as it anyway.

It could be the light getting better, after a few minutes it can change loads so will be enough to register but like you say could be your just getting better at tweaking the shots as you go could be hard to tell tbh!
Title: Re: Astro Photography
Post by: zpyder on August 17, 2013, 14:31:07 PM
Girlfriend went out with friends last night and I was the taxi. Ended up getting back home at about 2-2.30. Around here they turn the streetlights off after midnight, I was surprised by how dark it was. Still enough light pollution, but I guess it's a good way to practice technique instead of wasting a trip out somewhere more remote

(http://farm6.staticflickr.com/5514/9531014490_ffb60ee113.jpg) (http://www.flickr.com/photos/zpyder/9531014490/)
Astro (http://www.flickr.com/photos/zpyder/9531014490/) by Chris_Moody (http://www.flickr.com/people/zpyder/), on Flickr
Title: Re: Astro Photography
Post by: Russell on August 22, 2013, 21:41:59 PM
Just had a look on flickr and that was a stacked shot?  If so can you give a bit of info on what you took etc, not managed to get a stacking shot to work yet but I'll be trying again later this year hopefully.

Full size it looks like the stars are a little out of focus, or could be the start of some trails but full size you see just how many stars you've managed to get so even if there was a bit of light pollution its come off nicely.

I'd love to get myself something like a Tokina 11-16 f2.8 to get more star stuff, should be getting a 17-50 f2.8 in a few months so that'll have to do for now.
Title: Re: Astro Photography
Post by: zpyder on August 23, 2013, 19:54:18 PM
Stacked shot. 15 light frames 5 dark.
 
Manual mode. F2.8. ISO 1600. 17mm. 20 second exposures. I couldn't be arsed working out the 400/17 so assumed it'd be close to, or slightly above 20 seconds for exposure before star trails. I also used a radio remote control to take the shots (I think if I do this again I'll hook up the tablet computer to the camera and use an app to just interval shoot).

I used deep sky stacker and the RAW files. Pretty much just loaded the light and dark frames and then just processed it as was. I then used Adobe CameraRaw to post process a tad to adjust contrast and colour a bit.

The stars are likely out of focus as I couldn't really tell whether it was in focus due to light. I also recalled something about you don't focus to the limits of the infinity distance, so I focused as far as I could, and then tweaked it back a fraction. Probably a mistake!
Title: Re: Astro Photography
Post by: Russell on August 29, 2013, 13:55:55 PM
Stacked shot. 15 light frames 5 dark.
 
Manual mode. F2.8. ISO 1600. 17mm. 20 second exposures. I couldn't be arsed working out the 400/17 so assumed it'd be close to, or slightly above 20 seconds for exposure before star trails. I also used a radio remote control to take the shots (I think if I do this again I'll hook up the tablet computer to the camera and use an app to just interval shoot).

I used deep sky stacker and the RAW files. Pretty much just loaded the light and dark frames and then just processed it as was. I then used Adobe CameraRaw to post process a tad to adjust contrast and colour a bit.

The stars are likely out of focus as I couldn't really tell whether it was in focus due to light. I also recalled something about you don't focus to the limits of the infinity distance, so I focused as far as I could, and then tweaked it back a fraction. Probably a mistake!

Thanks for the info, hopefully I'll give something similar a go next month, going to Sorrento next week so once I get back from there I'll start keeping an eye open for some nice clear nights and see what I can get.

One thing, by dark frames do you just mean a shot with the lens cap on to use as a reference shot to help get rid of the noise?
Title: Re: Astro Photography
Post by: zpyder on August 29, 2013, 19:27:15 PM
Yeah, bang on. I alternated between around 5 dark and then the light set and then 5 dark again etc. Figured it'd be best to have the dark references at both ends of stacks etc.

Pretty sure that it's not the correct way of doing things, but at the level I am working at though, doing things textbook perfect etc probably is less important than just experimenting and getting the experience to see just what is actually happening!
Title: Re: Astro Photography
Post by: Russell on September 02, 2013, 22:13:01 PM
Yeah, bang on. I alternated between around 5 dark and then the light set and then 5 dark again etc. Figured it'd be best to have the dark references at both ends of stacks etc.

Pretty sure that it's not the correct way of doing things, but at the level I am working at though, doing things textbook perfect etc probably is less important than just experimenting and getting the experience to see just what is actually happening!

I need to do the same, I can do star trails stuff fine but not star fields so I need to have a bit of an experiment and trying to get them right, not too bothered if its not perfect just as long as I can get something that's workable and looks decent.

Its still annoying however that to get some really good results I could do with a full frame body with some nice f2.8 lens, not gonna happen anytime soon doh.
Title: Re: Astro Photography
Post by: Serious on November 14, 2014, 15:38:57 PM
https://www.youtube.com/watch?v=O_d5SaY5bLQ

Canon PowerShot SX60 HS moon video. The zoom on this camera is ridiculous, although later it isn't pure optical.
Title: Re: Astro Photography
Post by: Eggtastico on November 15, 2014, 16:30:13 PM
https://www.youtube.com/watch?v=O_d5SaY5bLQ

Canon PowerShot SX60 HS moon video. The zoom on this camera is ridiculous, although later it isn't pure optical.

next zoom test is on uranus