niteclicks said:
It's an induro carbon fiber that use with a wimberly mount ... Seems fairly stable with my 300. When I mount the 600 on the tracker its gets a bit wobbly but does ok as well as long as there is no wind.
Upvote
0
Deep Sky Astrophotography
- Thread starter jrista
- Start date
It's an induro carbon fiber that use with a wimberly mount ... Seems fairly stable with my 300. When I mount the 600 on the tracker its gets a bit wobbly but does ok as well as long as there is no wind.
I guess I need to look at one in person. I have an old meade lxd75 that I could not get good tracking out of that I had intended to be portable mount. But at time I was using an 8" Newtonian that acted like a sail in the lightest breeze. I may dig it out and see how it behaves with a lens. I would love to have something easier to haul on trips.
Upvote
0
niteclicks said:
This is the reason I got the Astro-track astrophoto package. The unit is about the size of two Dslrs (excluding the tripod) and I can pack in my luggage with the tripod. It has an st4 interface as well so you can add a scope and guider to the setup for longer exposures. I've taken up to 60 seconds on it and it tracks well even along the ecliptic. Haven't had a need to go much more than that yet due to light pollution. However I am planning a 2 week trip to Yellowstone next year and I'm shaking out all of the new gear now so I Dont have issues once I get there. It seems to be the most portable option yet can easily handle the gear I intend to take with me. 300 2.8L ii, 5d3 and 7d2 Both with grips.
I think it's design capacity is 11kg.
Upvote
0
My third attempt at m42. Canon 5d mkii and Tamron 150-600mm at 600mm f/6.3, 1 second iso 6400, 115 light frames and ten dark frames. Stacked in DSS and edited in lightroom.
116 seconds by Andy Hodapp, on Flickr
116 seconds by Andy Hodapp, on Flickr
Upvote
0
Great stuff, guys! Your really progressing!
One piece of advice: Try to get longer exposures, rather than stacking tons of short exposures. Noise does average out, if it is the right kind of noise. Thing about read noise, it adds in a certain way, and it does NOT average out like dark current noise or photon shot noise.
Here's the math (simplified a bit, it ignores other factors that I don't want to get into with you guys yet):
SNR = (n * S)/SQRT(n * (S + D + R^2))
n = sub count
S = signal
D = dark current
R = read noise
Notice here...R is SQUARED in the square root term. That basically makes it a constant. While everything else is scalar, R is squared, so it compounds as you combine more and more frames. It's the one kind of noise you have to watch out for, as if you combine lots of frames (115, for example) the read noise starts to add up, while all the rest of the noise averages out. The signal is combining as well, and the signal grows faster than the read noise, but read noise does not average out like everything else, so you have to be careful with it.
So, with the math out of the way, what does it mean? It means that getting the highest signal per sub is best. More specifically (and this involves more complicated math), you want to get your signal strength high enough in each sub that you totally swamp read noise with your "background sky". When you do that, you become photon shot noise limited, and read noise is effectively dealt with by a simple offset (i.e. when you stretch your data, you just shift the black point up, and that reduces the read noise contribution to zero.) Doing this with a DSLR doesn't actually require that you know the math...really, exposing long enough that the histogram for your images peaks at the 1/3rd mark (from the left-hand edge on most cameras and in all software, where the black point is) is generally enough to swamp read noise unless your combining more than a couple hundred frames.
I therefor strongly encourage you guys to get the longest subs you possibly can, before you start getting elongated, eggy, or trailed stars. That generally means exposing for much longer than 1 second, and that requires some kind of tracking mount. But the difference is massive. Even if you go from one second to five or ten seconds (which, without a tracking mount, if you have large enough pixels and/or a short enough focal length, that could be possible), that would be a very significant difference in per-sub SNR, which would result in significantly better integrations.
One piece of advice: Try to get longer exposures, rather than stacking tons of short exposures. Noise does average out, if it is the right kind of noise. Thing about read noise, it adds in a certain way, and it does NOT average out like dark current noise or photon shot noise.
Here's the math (simplified a bit, it ignores other factors that I don't want to get into with you guys yet):
SNR = (n * S)/SQRT(n * (S + D + R^2))
n = sub count
S = signal
D = dark current
R = read noise
Notice here...R is SQUARED in the square root term. That basically makes it a constant. While everything else is scalar, R is squared, so it compounds as you combine more and more frames. It's the one kind of noise you have to watch out for, as if you combine lots of frames (115, for example) the read noise starts to add up, while all the rest of the noise averages out. The signal is combining as well, and the signal grows faster than the read noise, but read noise does not average out like everything else, so you have to be careful with it.
So, with the math out of the way, what does it mean? It means that getting the highest signal per sub is best. More specifically (and this involves more complicated math), you want to get your signal strength high enough in each sub that you totally swamp read noise with your "background sky". When you do that, you become photon shot noise limited, and read noise is effectively dealt with by a simple offset (i.e. when you stretch your data, you just shift the black point up, and that reduces the read noise contribution to zero.) Doing this with a DSLR doesn't actually require that you know the math...really, exposing long enough that the histogram for your images peaks at the 1/3rd mark (from the left-hand edge on most cameras and in all software, where the black point is) is generally enough to swamp read noise unless your combining more than a couple hundred frames.
I therefor strongly encourage you guys to get the longest subs you possibly can, before you start getting elongated, eggy, or trailed stars. That generally means exposing for much longer than 1 second, and that requires some kind of tracking mount. But the difference is massive. Even if you go from one second to five or ten seconds (which, without a tracking mount, if you have large enough pixels and/or a short enough focal length, that could be possible), that would be a very significant difference in per-sub SNR, which would result in significantly better integrations.
Upvote
0
The D800/810 with black point hack has already proven to be a formiddable option for astrophotography. Seems soon Canon will not be the only company offering an astro-tuned DSLR:
http://nikonrumors.com/2015/02/01/rumors-new-special-nikon-d810-version-designed-for-deep-sky-astrophotography-with-increased-hydrogen-alfa-sensitivity.aspx/
Difference is Nikon would be offering the D810, a flagship model, in an astro-modded variant. I know a guy who does PHENOMENAL work with the D800:
http://www.astrobin.com/users/whwang/
My 5D III can't do that...at least, not with such little integration time. It's much noisier, even when imaging under extremely dark skies, with longer integration times. I'd need 10 hours minimum to get results that good.
I wonder what Canon's 5Ds will be like. I truly hope Canon addresses their read noise issues...
http://nikonrumors.com/2015/02/01/rumors-new-special-nikon-d810-version-designed-for-deep-sky-astrophotography-with-increased-hydrogen-alfa-sensitivity.aspx/
Difference is Nikon would be offering the D810, a flagship model, in an astro-modded variant. I know a guy who does PHENOMENAL work with the D800:
http://www.astrobin.com/users/whwang/
My 5D III can't do that...at least, not with such little integration time. It's much noisier, even when imaging under extremely dark skies, with longer integration times. I'd need 10 hours minimum to get results that good.
I wonder what Canon's 5Ds will be like. I truly hope Canon addresses their read noise issues...
Upvote
0
So I broke down and ordered a camranger. Mostly so I could use my ipad for micro focus in the field. Anyone else use a camranger for astrophotography and does it provide useful features?
I had been using a laptop for microfocus but I dreaded dragging that off to the midwest when I would have my tablet anyway.
I had been using a laptop for microfocus but I dreaded dragging that off to the midwest when I would have my tablet anyway.
Upvote
0
East Wind Photography said:
I know a bird photographer who uses one. He uses it to get difficult shots, like Kingfishers. I don't know of anyone who uses one for astro...but if it helps you focus, I say more power to you.
Upvote
0
Astronomy has been a interest of mine since I was 10 years old. Now, some 30 years later, an Astrotrac (tripod mounted star tracker (non-guided)), a DSLR and a few lenses have given me a chance of actually taking photos of the objects I saw in astronomy books, magazines, etc - and I am really stoked! Here's a few astro shots taken recently:
The Great Orion Nebula (M42 + M43 + Running Man)
Full spectrum modded 6D + 70-200 f2.8L II lens with x2 TC @ 400mm. Tracked using an Astrotrac.
4x120s, 8x60s, 4x20s, 4x8s and 4x3s at f5.6 on ISO3200. Dark frame subtraction on the 120s and 60s shots.
Aligned with PT Gui and processed with Fitswork.
Lagoon Nebula and the Trifid Nebula
Full spectrum modded 6D + 70-200 f2.8L II lens with x2 TC @ 400mm. Tracked using an Astrotrac.
4x120s, 4x30s, 4x8s at ISO800 + 10x120s at ISO3200. All at f5.6. Dark frame subtraction on the 120s shots.
Aligned with PT Gui and processed with Fitswork.
Eta Carina
Full spectrum modded Canon 6D, 200mm, ISO3200, 4x120s, 4x30s, 4x8s and 4x3s. AstroTrac. Hutech LPS-D1 lens mounted filter
Eta Carina - Wide field
Full spectrum modded Canon 6D, 200mm, ISO3200, 4x120s, 4x30s, 4x8s and 4x3s. AstroTrac. Astronomic CLS-CCD XL-Clip filter
Comet Lovejoy (C/2014 Q2)
Canon 6D
70-200 f2.8L II + 2x TC @ 400mm, f5.6
20x120s exposures at ISO3200
Astrotrac used for tracking the stars
Heart of the Milky Way Widefield
Mosaic using a Sigma 35mm @ f2.2 on a full spectrum Canon 6D. An Astronomic 'L' clip in filter was used. Astrotrac used for tracking.
Hope you enjoy.
The Great Orion Nebula (M42 + M43 + Running Man)
Full spectrum modded 6D + 70-200 f2.8L II lens with x2 TC @ 400mm. Tracked using an Astrotrac.
4x120s, 8x60s, 4x20s, 4x8s and 4x3s at f5.6 on ISO3200. Dark frame subtraction on the 120s and 60s shots.
Aligned with PT Gui and processed with Fitswork.
Lagoon Nebula and the Trifid Nebula
Full spectrum modded 6D + 70-200 f2.8L II lens with x2 TC @ 400mm. Tracked using an Astrotrac.
4x120s, 4x30s, 4x8s at ISO800 + 10x120s at ISO3200. All at f5.6. Dark frame subtraction on the 120s shots.
Aligned with PT Gui and processed with Fitswork.
Eta Carina
Full spectrum modded Canon 6D, 200mm, ISO3200, 4x120s, 4x30s, 4x8s and 4x3s. AstroTrac. Hutech LPS-D1 lens mounted filter
Eta Carina - Wide field
Full spectrum modded Canon 6D, 200mm, ISO3200, 4x120s, 4x30s, 4x8s and 4x3s. AstroTrac. Astronomic CLS-CCD XL-Clip filter
Comet Lovejoy (C/2014 Q2)
Canon 6D
70-200 f2.8L II + 2x TC @ 400mm, f5.6
20x120s exposures at ISO3200
Astrotrac used for tracking the stars
Heart of the Milky Way Widefield
Mosaic using a Sigma 35mm @ f2.2 on a full spectrum Canon 6D. An Astronomic 'L' clip in filter was used. Astrotrac used for tracking.
Hope you enjoy.
Attachments
Upvote
0
EXCELLENT images, Cazza! Your modded 6D sucks out far more Ha than my unmodded 5D III does...really amazing. I'm amazed these are all tracked using the AstroTrac...that little thing must handle the weight very well.
Looks like you have access to more southerly skies. The Carina Nebula is something I can't see, but I find it fascinating. Love your wide field of the area, truly excellent.
Your Lovejoy is superb as well!
Welcome to the forums!
Looks like you have access to more southerly skies. The Carina Nebula is something I can't see, but I find it fascinating. Love your wide field of the area, truly excellent.
Your Lovejoy is superb as well!
Welcome to the forums!
Upvote
0
jrista said:
Thanks jrista!
I live on the Sunshine Coast (about 26deg S) - just north of Brisbane, Australia - so I am lucky to have a full view of the many goodies in the southern sky.
Yes, the full spectrum modification does make a huge difference - like about 400%+ increase in Ha sensitivity. A visible+Ha band pass filter that cuts infrared is essential. The FS 6D is also very handy for daytime (and night time) IR work.
The Astrotrac does pretty well, but can be fiddly to get right. I usually spend about 45min drift aligning before shooting. And you have to keep the center of gravity of the camera and lens close to the center of rotation of the Astrotrac. If I'm lucky, on a good night, I can get 4min subs with a 400mm FL.
BTW - Excellent work on your website! Well done with your recent images of Andromeda, Pleiades, M42 and horsehead - standouts for me. All with an unmodded 5DIII?
Upvote
0
cazza132 said:
Yeah, once you get rid of Canon's stock IR/UV cutoff filter, things improve dramatically for astro. I've resisted doing that with my 5D III, as I don't want to mess with it's existing IQ for my birds and wildlife, and am planning to get a mono CCD with filter wheel and narrow band filters soon here anyway.
The 5D III definitely struggles to get any Ha though.
cazza132 said:
Thanks for the insights. It is possible to use PHD to do very rapid drift align. I am not sure if that would be possible on the astrotrac, PHD has compatibility with certain guide cameras and may not work with a DSLR. I can dial in a PA error of about 30 arcseconds or less in about 10 minutes or so using the technique I describe here, though:
http://www.cloudynights.com/topic/472874-drift-alignment-with-phd2-the-bookmark-technique/
If you can figure a way to make it work, it might get you dialed in much faster.
Upvote
0
Here is another. I just had a run of six clear nights...something I've never seen before...and got a ton of data on several targets. Most were galaxies, the one nebula was Rosette. This is an 11 hour integration (164x240s subs).
5D III + 600mm f/4 + 1.4x (840mm 1.55"/px) on Atlas mount
Two versions, one "narrow band" like and one "natural color":
This is my longest integration to date, at 11 hours. I did this from my back yard with an IDAS LPS-P2 light pollution filter. That's replacing my Astronomik CLS filter, and it's actually quite amazing. Not entirely dark site quality data, but quite good data nevertheless.
5D III + 600mm f/4 + 1.4x (840mm 1.55"/px) on Atlas mount
Two versions, one "narrow band" like and one "natural color":
This is my longest integration to date, at 11 hours. I did this from my back yard with an IDAS LPS-P2 light pollution filter. That's replacing my Astronomik CLS filter, and it's actually quite amazing. Not entirely dark site quality data, but quite good data nevertheless.
Upvote
0
Click said:
+1 Indeed amazing shots
jrista said:Here is another. I just had a run of six clear nights...something I've never seen before...and got a ton of data on several targets. Most were galaxies, the one nebula was Rosette. This is an 11 hour integration (164x240s subs).
5D III + 600mm f/4 + 1.4x (840mm 1.55"/px) on Atlas mount
Two versions, one "narrow band" like and one "natural color":
This is my longest integration to date, at 11 hours. I did this from my back yard with an IDAS LPS-P2 light pollution filter. That's replacing my Astronomik CLS filter, and it's actually quite amazing. Not entirely dark site quality data, but quite good data nevertheless.
these are really beautiful, i like the second one most but both are superb, maybe you should move to a more sunny climate for more chances to get longer exposures, it seem that's your only real limitation
Upvote
0
jrista said:
John,
Outstanding Details! This must look great at 1:1. One comment, on the second image the blue halos around the stars are a bit detracting. Cleaning those up, and a little color correction (less blue) in the stars would really strengthen that image. Im guessing these are left over from your Light Pollution Filter. Excellent work!
Upvote
0
Canon1 said:
Actually, the first image is more what I got strait out of camera. The IDAS LPS-P2 actually produces great stars with great color balance, but it doesn't handle the deeper pinks of emission nebula as well. The blue halos are due to the processing, which I am working on. I need to figure out how to properly reduce the stars in both the luminance and RGB images before combining them. I am also working on doing some pre-stretch masking on the stars in the second color version to prevent them from becoming overly blue (a more neutral white-based would be ideal.)
Upvote
0
Wow, you guys are putting up some amazing shots. I really only started trying my hand at some astrophotography recently, and only using a 70D + 70-200 f/4, but here is my first attempt at the Orion Nebula:
Orion Nebula by Justin Kane, on Flickr
This is nowhere near what some of you guys are doing, but it is really the first deep sky object I have tried to image. I actually took this from the balcony at my house in northern San Diego. This was 87 1.0s, ISO 1600 subs with 48 dark frames and 21 bias frames with my lens @ 200mm f/4. I also tried using 1.6s exposures but was getting some motion blur and didn't think it looked as good. Even though it doesn't fill the frame it is really cool how DSS can clean up the image and show some of these objects.
I am really starting to understand, though, that to step it up to the next level you NEED a tracker to increase your exposure times. I'm not sure if I'm ready to shell out for one though, lol.
Attached is a 50% crop...it was looking kinda fuzzy at 100% crop.
Orion Nebula by Justin Kane, on Flickr
This is nowhere near what some of you guys are doing, but it is really the first deep sky object I have tried to image. I actually took this from the balcony at my house in northern San Diego. This was 87 1.0s, ISO 1600 subs with 48 dark frames and 21 bias frames with my lens @ 200mm f/4. I also tried using 1.6s exposures but was getting some motion blur and didn't think it looked as good. Even though it doesn't fill the frame it is really cool how DSS can clean up the image and show some of these objects.
I am really starting to understand, though, that to step it up to the next level you NEED a tracker to increase your exposure times. I'm not sure if I'm ready to shell out for one though, lol.
Attached is a 50% crop...it was looking kinda fuzzy at 100% crop.
Attachments
Upvote
0
Nice work, Schmave. Glad you gave it a try. I would be willing to bet, with a little bit more tolerance for some noise, that your data has more information in it than you think. It's a classic beginner "mistake" to try and make the background totally black. Thing is, space isn't black (very, very few areas of the sky actually have a black background, and none of the areas with emission nebula, which are all along the milky way, have a black background at all...there is tons of faint dust and filaments of emission nebula scattered all about the milky way.)
I would work on keeping your background level above black...maybe 20-30 levels. You should be able to bring out more of the nebula then. You will have more noise, but noise is just a fact of life with astrophotography...we work with such weak signals.
Keep it up! You've just started a very long journey. The next step would be to get some kind of tracking mount...be it a Polari or AstroTrac, or something larger and more expensive, once you can track, you'll see your ability to get deeper exposures increase dramatically.
Glad you gave it a try. I would be willing to bet, with a little bit more tolerance for some noise, that your data has more information in it than you think. It's a classic beginner "mistake" to try and make the background totally black. Thing is, space isn't black (very, very few areas of the sky actually have a black background, and none of the areas with emission nebula, which are all along the milky way, have a black background at all...there is tons of faint dust and filaments of emission nebula scattered all about the milky way.) I would work on keeping your background level above black...maybe 20-30 levels. You should be able to bring out more of the nebula then. You will have more noise, but noise is just a fact of life with astrophotography...we work with such weak signals.
Keep it up! You've just started a very long journey. The next step would be to get some kind of tracking mount...be it a Polari or AstroTrac, or something larger and more expensive, once you can track, you'll see your ability to get deeper exposures increase dramatically.
Upvote
0