December 20, 2014, 01:18:35 PM

Author Topic: jrista et al, Why Astrophotography?  (Read 4710 times)

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #15 on: May 10, 2014, 08:19:02 PM »
Let me try it this way. Have you seen images produces with PlaneWaves on Paramounts, AP mounts, and 10Micron mounts? Have you ever compared them with the images your AT72ED produce?

I don't mean to offend, honestly...but no, I do not believe an AT72ED and a ZEQ25 are going to produce IQ that even remotely compares to a PlaneWave or RCOS scope on a high precision mount. I spend a lot of time looking at peoples images on AstroBin. A LOT of people use the Astro-Tech refractors (well, a LOT of people use Astro-Tech scopes period, including me shortly here as I'm about to order either the 8" or 10" RC) because they are an extremely good deal for the quality you ARE getting. Even those who are quite skilled and know how to get round stars still can't get the kind of CLEAN stars that a PlaneWave gets you.

If you look around and compare what $3000 worth of equipment can produce in the majority of cases, vs. what $20k-$40k can do in every case...you'll understand where I'm coming from.

My $13,000 lens could probably serve me a hell of a lot better if I put it on a higher quality mount. I'd also probably get at least twice as much sky time out of it if I had it on a mount I did not have to constantly fiddle with to keep tracking smoothly, or to get pointed at the right place in the sky, etc. There are just things you have to deal with when using lower-end equipment that consumes a very considerable amount of time. I have a four hour window to image from my backyard, given how the trees and houses around me affect my line of sight. On any given night, I usually get about 2 hours of actual time imaging. The rest is spent fiddling with getting my polar alignment down to 1' or less, getting my guiding set up and running (If you have ever used the Orion SSAG with PHD, you would know how you have to first find an acceptable guide scar (which, with the really low sensitivity of the SSAG, is often a real PITA), then let it calibrate which, assuming you use the recommended ~20 steps, can take at least five minutes, then let it "settle" once it actually starts guiding), then get your focus dialed in, frame and center your subject, get your imaging sequence set up and finally get it started. If the temperature is changing throughout the night, you gotta keep an eye on your focus, so you usually produce about five subs, then refocus, produce five more, then refocus, etc. If ANYTHING happens to your guide star...a light high altitude cloud of just the right density moves over it, you can lose it, then you lose your guiding, and your tracking goes to hell (from 2" to 15" or worse!) You can automate a lot of this, but all these little things take time. Using SGP, you can automate your pointing, centering, dithering, guide recalibration, focusing, filter selection, etc. All of those things consume about 40% of that 4-hour window.

Now, throw in a high end tracking mount that doesn't need guiding at all. Suddenly, the only things you have to do every few subs now are check focus, and maybe choose a new filter. All the other cruft to make sure your still pointed at the right thing, still properly centered on it, all the guiding crap, etc. is just no longer necessary. Focusing can still take away some time, but not nearly as much, so you have the ability to produce a lot more subs during your window of opportunity each night. Having enough subs to stack and average out all the noise is one of the most important things that I see high end imagers doing differently. You might see people using lower end equipment getting 30 4-8 minute subs with a DSLR, when they need at least 100 to reduce noise to manageable levels. The guys with RCOS and PlaneWave scopes are getting 15-20 10 minute Luminance subs, along with 9-15 10 minute subs each for R, G, and B. That's anywhere from 42 to 65 frames, each of which are higher quality with more signal and better SNR, than the 30 low SNR subs the guys using modded 350Ds on Orion or Astro-Tech refractors. It's a total integration time of at least 650 minutes, vs. a total integration time of maybe 240 minutes or so.

I understand why imagers with AT72EDs and ZEQ25's or AT6RCs and Atlases using modded DSLRs or $700 Atik OSC CCDs don't get more than 2-3 hours worth of subs. There are very good reasons for it, not saying there aren't. It's a far greater effort, requiring a far more active investment to keep your setup producing subs that don't need to be culled and will contribute nicely to the final integration, when using lower end equipment. I think that just speaks volumes about why someone would invest some serious money into high end equipment if they want to take their imaging to the next level, where their stars aren't just round, but perfect, where their color saturation isn't just good, it's sublime, and where their detail is just mind blowing. ;)

While I do agree with everything you say, it's just that not everyone can spend 40,000$ to get optimum results. :(  Also, if you own a 13,000$ telescope (your 600mm lens) Why didn't you get a high precision EQ Mount? ???
« Last Edit: May 10, 2014, 08:21:12 PM by traingineer »
7D | 24-70mm F2.8 I | 50mm F1.8 II

canon rumors FORUM

Re: jrista et al, Why Astrophotography?
« Reply #15 on: May 10, 2014, 08:19:02 PM »

jrista

  • Canon EF 400mm f/2.8L IS II
  • *********
  • Posts: 4814
  • EOL
    • View Profile
    • Nature Photography
Re: jrista et al, Why Astrophotography?
« Reply #16 on: May 10, 2014, 08:43:13 PM »
While I do agree with everything you say, it's just that not everyone can spend 40,000$ to get optimum results. :(  Also, if you own a 13,000$ telescope (your 600mm lens) Why didn't you get a high precision EQ Mount? ???

Oh yeah, I'm not saying everyone can or even should spend that kind of money. Just saying that if you want to get great quality, it tends to cost a whole lot more to get it with astrophotography than it does with normal photography. With normal photography, if you have the skill, you can get very good results with fairly minimal gear. The gear matters, but not as much. With astrophotography, the quality of the gear has rather exceptional importance, which makes it a very (saddeningly, even) expensive hobby.

I do plan to get a 10Micron GM2000HPS UP mount. It's a $20,000 mount, one of the best (personally, I think it is the best...at the moment, 10Micron is the only manufacturer that has moved all the sky modeling right into the mount. The other high end manufacturers like Astro-Physics or Software Bisque still have all the modeling in software, that has to run on a computer plugged into the mount.) I haven't gotten it yet because, the obvious reason, it's ridiculously expensive. :P I just bought my 600mm lens less than a year ago (summer last year), and I still haven't really recovered from that expense.

The other reason is as much as I'd like to have it now, I can still learn with the ~$2500 worth of mount gear and my 600mm lens. Before I invest in a 10Micron mount and even an Astro-Tech AT16RC Truss (which would be $27,000), I want to have more skill. Acquiring images is only a small part of the process of producing great astrophotography images. Since you do astrophotography yourself, you surely know this: Processing is at least half, it not more like 2/3rds, of the art. I might spend six to eight hours acquiring images, which really involves about 2-3 hours of actual personal time invested (the rest is just the mount and imager and guider doing their things on their own.) I can easily spend a few hours sifting through my subs, picking the good ones and culling the bad ones and finally stacking, then another 10 hours at least of processing and tweaking and fine tuning my images in PixInsight and Photoshop. I've revisited some of my works two or three times, trying to get better results each time. In my Rosette image, I've probably got 20 hours of processing time in. I just started revisiting my Monkey Head image, which has at least 15 hours already, and I think I'll be spending at least another 5-10 hours on it to get noise levels down to an acceptable level and lift up some of the dimmer nebulosity.

Given that so much of the artform of astrophotography involves everything that comes AFTER image acquisition, I decided I should get good at that first, and make sure I am even capable of achieving the skill level I believe is necessary to produce Robert Gendler or Russel Croman level images...before I dropped $30k or more into more equipment.

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #17 on: May 10, 2014, 08:54:57 PM »
While I do agree with everything you say, it's just that not everyone can spend 40,000$ to get optimum results. :(  Also, if you own a 13,000$ telescope (your 600mm lens) Why didn't you get a high precision EQ Mount? ???

Oh yeah, I'm not saying everyone can or even should spend that kind of money. Just saying that if you want to get great quality, it tends to cost a whole lot more to get it with astrophotography than it does with normal photography. With normal photography, if you have the skill, you can get very good results with fairly minimal gear. The gear matters, but not as much. With astrophotography, the quality of the gear has rather exceptional importance, which makes it a very (saddeningly, even) expensive hobby.

I do plan to get a 10Micron GM2000HPS UP mount. It's a $20,000 mount, one of the best (personally, I think it is the best...at the moment, 10Micron is the only manufacturer that has moved all the sky modeling right into the mount. The other high end manufacturers like Astro-Physics or Software Bisque still have all the modeling in software, that has to run on a computer plugged into the mount.) I haven't gotten it yet because, the obvious reason, it's ridiculously expensive. :P I just bought my 600mm lens less than a year ago (summer last year), and I still haven't really recovered from that expense.

The other reason is as much as I'd like to have it now, I can still learn with the ~$2500 worth of mount gear and my 600mm lens. Before I invest in a 10Micron mount and even an Astro-Tech AT16RC Truss (which would be $27,000), I want to have more skill. Acquiring images is only a small part of the process of producing great astrophotography images. Since you do astrophotography yourself, you surely know this: Processing is at least half, it not more like 2/3rds, of the art. I might spend six to eight hours acquiring images, which really involves about 2-3 hours of actual personal time invested (the rest is just the mount and imager and guider doing their things on their own.) I can easily spend a few hours sifting through my subs, picking the good ones and culling the bad ones and finally stacking, then another 10 hours at least of processing and tweaking and fine tuning my images in PixInsight and Photoshop. I've revisited some of my works two or three times, trying to get better results each time. In my Rosette image, I've probably got 20 hours of processing time in. I just started revisiting my Monkey Head image, which has at least 15 hours already, and I think I'll be spending at least another 5-10 hours on it to get noise levels down to an acceptable level and lift up some of the dimmer nebulosity.

Given that so much of the artform of astrophotography involves everything that comes AFTER image acquisition, I decided I should get good at that first, and make sure I am even capable of achieving the skill level I believe is necessary to produce Robert Gendler or Russel Croman level images...before I dropped $30k or more into more equipment.

To he honest, post processing is my least favourite part, until I finished the image , and good luck to getting that mount! c:
« Last Edit: May 10, 2014, 08:56:39 PM by traingineer »
7D | 24-70mm F2.8 I | 50mm F1.8 II

jrista

  • Canon EF 400mm f/2.8L IS II
  • *********
  • Posts: 4814
  • EOL
    • View Profile
    • Nature Photography
Re: jrista et al, Why Astrophotography?
« Reply #18 on: May 10, 2014, 09:10:28 PM »
To he honest, post processing is my least favourite part, until I finished the image ,

I hear that! :) I haven't had many of those moments lately...I tried to do galaxy imaging with my wide field 600mm lens...wasn't nearly as successful as I originally thought it would be. It's pretty hard to do galaxy imaging in a wide field under polluted skies.

and good luck to getting that mount! c:

I'm actually really hoping the price on the absolute encoders these mounts use drops in the next couple of years, so that by the time I'm finally ready to invest in one, they'll be cheaper. Astro-Physics just started adding encoders to their mounts (they don't seem to be doing it as well as 10Micron). Their lower-end mounts (which are still all ultra high end in general) cost around $8000 or so without the encoders. Just adding the encoders pushes the price up to $15,000 or more. That's almost double the cost. If the cost of these high resolution, absolute encoders comes down in the future, these nice high end mounts should come down in cost as well, and I intend to be all ready to pounce the moment they do. :P

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #19 on: May 10, 2014, 09:16:50 PM »
To he honest, post processing is my least favourite part, until I finished the image ,

I hear that! :) I haven't had many of those moments lately...I tried to do galaxy imaging with my wide field 600mm lens...wasn't nearly as successful as I originally thought it would be. It's pretty hard to do galaxy imaging in a wide field under polluted skies.

and good luck to getting that mount! c:

I'm actually really hoping the price on the absolute encoders these mounts use drops in the next couple of years, so that by the time I'm finally ready to invest in one, they'll be cheaper. Astro-Physics just started adding encoders to their mounts (they don't seem to be doing it as well as 10Micron). Their lower-end mounts (which are still all ultra high end in general) cost around $8000 or so without the encoders. Just adding the encoders pushes the price up to $15,000 or more. That's almost double the cost. If the cost of these high resolution, absolute encoders comes down in the future, these nice high end mounts should come down in cost as well, and I intend to be all ready to pounce the moment they do. :P

You know, there is 1 main advantage I noticed with inexpensive telescopes/mounts, they're usually a lot lighter and smaller.
7D | 24-70mm F2.8 I | 50mm F1.8 II

jrista

  • Canon EF 400mm f/2.8L IS II
  • *********
  • Posts: 4814
  • EOL
    • View Profile
    • Nature Photography
Re: jrista et al, Why Astrophotography?
« Reply #20 on: May 10, 2014, 10:02:06 PM »
You know, there is 1 main advantage I noticed with inexpensive telescopes/mounts, they're usually a lot lighter and smaller.

Very true. I guess that's one of the biggest pros of going inexpensive. If you need portability, then high end stuff just isn't viable. That's one of the reasons I got the Orion Atlas...I do take it out to dark sites about 40 miles away or so. The 10Micron GM2000HPS has an ultra portable version, where the head disassembles into two lighter weight parts, plus the control box. But it's still heavier than the Atlas...

I do love using my 600mm lens as a telescope. It's relatively short, so good for wider field work. Optically, it's as good as the $12,000 Officina Stellare HiPer API 152, and faster. Once I get a mono CCD camera, it will make for a superb wide field setup. I also like using my 100mm and 50mm lenses with my DSLR mounted to a Vixen dovetail for really wide field stuff. I haven't had many opportunities to do that...but the first clear night in almost four weeks is supposed to happen on the 13th...I plan to take the Atlas, my DSLR and those two lenses out to a dark site and see if I can get some wide field shots of the milky way core, scorpius, and a few of the Ha nebulas near the galactic core. :) I've been waiting for the 13th for so long, I'm kind of chomping at the bit. :P

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #21 on: May 10, 2014, 10:58:24 PM »
You know, there is 1 main advantage I noticed with inexpensive telescopes/mounts, they're usually a lot lighter and smaller.

Very true. I guess that's one of the biggest pros of going inexpensive. If you need portability, then high end stuff just isn't viable. That's one of the reasons I got the Orion Atlas...I do take it out to dark sites about 40 miles away or so. The 10Micron GM2000HPS has an ultra portable version, where the head disassembles into two lighter weight parts, plus the control box. But it's still heavier than the Atlas...

I do love using my 600mm lens as a telescope. It's relatively short, so good for wider field work. Optically, it's as good as the $12,000 Officina Stellare HiPer API 152, and faster. Once I get a mono CCD camera, it will make for a superb wide field setup. I also like using my 100mm and 50mm lenses with my DSLR mounted to a Vixen dovetail for really wide field stuff. I haven't had many opportunities to do that...but the first clear night in almost four weeks is supposed to happen on the 13th...I plan to take the Atlas, my DSLR and those two lenses out to a dark site and see if I can get some wide field shots of the milky way core, scorpius, and a few of the Ha nebulas near the galactic core. :) I've been waiting for the 13th for so long, I'm kind of chomping at the bit. :P

Luckily, it won't be Friday on the 13th but anyway, I tried using my Sigma 105mm on the 7D, and I found it near impossible to get near accurate focusing, especially on the moon. Mainly because you have to quickly turn the ring slightly to make the focusing system move, otherwise, it doesn't focus. :'( I also have an image of Jupiter and it's moons.
(deep sky stacker was used)
« Last Edit: May 10, 2014, 11:01:59 PM by traingineer »
7D | 24-70mm F2.8 I | 50mm F1.8 II

canon rumors FORUM

Re: jrista et al, Why Astrophotography?
« Reply #21 on: May 10, 2014, 10:58:24 PM »

jrista

  • Canon EF 400mm f/2.8L IS II
  • *********
  • Posts: 4814
  • EOL
    • View Profile
    • Nature Photography
Re: jrista et al, Why Astrophotography?
« Reply #22 on: May 10, 2014, 11:02:44 PM »
You know, there is 1 main advantage I noticed with inexpensive telescopes/mounts, they're usually a lot lighter and smaller.

Very true. I guess that's one of the biggest pros of going inexpensive. If you need portability, then high end stuff just isn't viable. That's one of the reasons I got the Orion Atlas...I do take it out to dark sites about 40 miles away or so. The 10Micron GM2000HPS has an ultra portable version, where the head disassembles into two lighter weight parts, plus the control box. But it's still heavier than the Atlas...

I do love using my 600mm lens as a telescope. It's relatively short, so good for wider field work. Optically, it's as good as the $12,000 Officina Stellare HiPer API 152, and faster. Once I get a mono CCD camera, it will make for a superb wide field setup. I also like using my 100mm and 50mm lenses with my DSLR mounted to a Vixen dovetail for really wide field stuff. I haven't had many opportunities to do that...but the first clear night in almost four weeks is supposed to happen on the 13th...I plan to take the Atlas, my DSLR and those two lenses out to a dark site and see if I can get some wide field shots of the milky way core, scorpius, and a few of the Ha nebulas near the galactic core. :) I've been waiting for the 13th for so long, I'm kind of chomping at the bit. :P

Luckily, it won't be Friday on the 13th but anyway, I tried using my Sigma 105mm on the 7D, and I found near impossible to get near accurate focusing, especially on the moon. I also have an image of Jupiter and it's moons.
(deep sky stacker was used)

How are you focusing? Live view 10x? You should be able to get pretty accurate in-camera, especially with the short focal length of 105mm. Trying to focus through the viewfinder is pretty much impossible. I can't even do that with my 600mm lens. I either use live view at 10x zoom, or I use BackyardEOS in it's focusing mode while tethered to the camera.

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #23 on: May 10, 2014, 11:15:08 PM »
You know, there is 1 main advantage I noticed with inexpensive telescopes/mounts, they're usually a lot lighter and smaller.

Very true. I guess that's one of the biggest pros of going inexpensive. If you need portability, then high end stuff just isn't viable. That's one of the reasons I got the Orion Atlas...I do take it out to dark sites about 40 miles away or so. The 10Micron GM2000HPS has an ultra portable version, where the head disassembles into two lighter weight parts, plus the control box. But it's still heavier than the Atlas...

I do love using my 600mm lens as a telescope. It's relatively short, so good for wider field work. Optically, it's as good as the $12,000 Officina Stellare HiPer API 152, and faster. Once I get a mono CCD camera, it will make for a superb wide field setup. I also like using my 100mm and 50mm lenses with my DSLR mounted to a Vixen dovetail for really wide field stuff. I haven't had many opportunities to do that...but the first clear night in almost four weeks is supposed to happen on the 13th...I plan to take the Atlas, my DSLR and those two lenses out to a dark site and see if I can get some wide field shots of the milky way core, scorpius, and a few of the Ha nebulas near the galactic core. :) I've been waiting for the 13th for so long, I'm kind of chomping at the bit. :P

Luckily, it won't be Friday on the 13th but anyway, I tried using my Sigma 105mm on the 7D, and I found near impossible to get near accurate focusing, especially on the moon. I also have an image of Jupiter and it's moons.
(deep sky stacker was used)

How are you focusing? Live view 10x? You should be able to get pretty accurate in-camera, especially with the short focal length of 105mm. Trying to focus through the viewfinder is pretty much impossible. I can't even do that with my 600mm lens. I either use live view at 10x zoom, or I use BackyardEOS in it's focusing mode while tethered to the camera.

I used 10x live fiew and manual focusing, turning the ring as slowly as possible.
« Last Edit: May 10, 2014, 11:16:49 PM by traingineer »
7D | 24-70mm F2.8 I | 50mm F1.8 II

jrista

  • Canon EF 400mm f/2.8L IS II
  • *********
  • Posts: 4814
  • EOL
    • View Profile
    • Nature Photography
Re: jrista et al, Why Astrophotography?
« Reply #24 on: May 10, 2014, 11:26:25 PM »
How are you focusing? Live view 10x? You should be able to get pretty accurate in-camera, especially with the short focal length of 105mm. Trying to focus through the viewfinder is pretty much impossible. I can't even do that with my 600mm lens. I either use live view at 10x zoom, or I use BackyardEOS in it's focusing mode while tethered to the camera.

I used 10x live fiew and manual focusing, turning the ring as slowly as possible.

Well, that's the right technique. Are you having trouble because the camera is shaking? Sometimes it actually helps to pretty much grab the whole rig, and balance it against yourself with as much surface area as possible. When the camera just kind of hangs free, it is sometimes actually more susceptible to wild shake than if it is being actively balanced by you. You'll still have some shake, but it should be slower and less problematic for your focusing.

BackyardEOS is a program that runs on a laptop or Windows 8 tablet that has a focusing mode that can control the lens' focus group directly. It has fast, medium, and slow controls, and it's actually the best way to focus DSLRs. The program costs about $50, but I've found it to be completely invaluable, especially for focusing my DSLR for astrophotography. If you can't get your focusing figured out using live view and 10x zoom, and are serious enough to spend the fifty bucks, BYEOS will definitely do the trick.

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #25 on: May 10, 2014, 11:29:36 PM »
How are you focusing? Live view 10x? You should be able to get pretty accurate in-camera, especially with the short focal length of 105mm. Trying to focus through the viewfinder is pretty much impossible. I can't even do that with my 600mm lens. I either use live view at 10x zoom, or I use BackyardEOS in it's focusing mode while tethered to the camera.

I used 10x live fiew and manual focusing, turning the ring as slowly as possible.

Well, that's the right technique. Are you having trouble because the camera is shaking? Sometimes it actually helps to pretty much grab the whole rig, and balance it against yourself with as much surface area as possible. When the camera just kind of hangs free, it is sometimes actually more susceptible to wild shake than if it is being actively balanced by you. You'll still have some shake, but it should be slower and less problematic for your focusing.

BackyardEOS is a program that runs on a laptop or Windows 8 tablet that has a focusing mode that can control the lens' focus group directly. It has fast, medium, and slow controls, and it's actually the best way to focus DSLRs. The program costs about $50, but I've found it to be completely invaluable, especially for focusing my DSLR for astrophotography. If you can't get your focusing figured out using live view and 10x zoom, and are serious enough to spend the fifty bucks, BYEOS will definitely do the trick.

Shake wasn't an issue, as I said before, the Sigma's focusing ring is just not good enough for slow/steady turning. I have already looked at Backyard EOS before and it is a very nice program. The 2 shots I have were just quick/rushed ones I did a few hours ago, just step up the tripod, kept it stable, point at object, focus and take the images.
7D | 24-70mm F2.8 I | 50mm F1.8 II

jrista

  • Canon EF 400mm f/2.8L IS II
  • *********
  • Posts: 4814
  • EOL
    • View Profile
    • Nature Photography
Re: jrista et al, Why Astrophotography?
« Reply #26 on: May 10, 2014, 11:31:26 PM »
How are you focusing? Live view 10x? You should be able to get pretty accurate in-camera, especially with the short focal length of 105mm. Trying to focus through the viewfinder is pretty much impossible. I can't even do that with my 600mm lens. I either use live view at 10x zoom, or I use BackyardEOS in it's focusing mode while tethered to the camera.

I used 10x live fiew and manual focusing, turning the ring as slowly as possible.

Well, that's the right technique. Are you having trouble because the camera is shaking? Sometimes it actually helps to pretty much grab the whole rig, and balance it against yourself with as much surface area as possible. When the camera just kind of hangs free, it is sometimes actually more susceptible to wild shake than if it is being actively balanced by you. You'll still have some shake, but it should be slower and less problematic for your focusing.

BackyardEOS is a program that runs on a laptop or Windows 8 tablet that has a focusing mode that can control the lens' focus group directly. It has fast, medium, and slow controls, and it's actually the best way to focus DSLRs. The program costs about $50, but I've found it to be completely invaluable, especially for focusing my DSLR for astrophotography. If you can't get your focusing figured out using live view and 10x zoom, and are serious enough to spend the fifty bucks, BYEOS will definitely do the trick.

Shake wasn't an issue, as I said before, the Sigma's focusing ring is just not good enough for slow/steady turning. I have already looked at Backyard EOS before and it is a very nice program. The 2 shots I have were just quick/rushed ones I did a few hours ago, just step up the tripod, kept it stable, point at object, focus and take the images.

If it really is the manual focus ring, then BYEOS might just do the trick. It focuses electronically, so the build quality of the manual focus ring really doesn't matter. If the lens focuses well when using AF, then you would have very fine grained control with BYEOS. You should be able to get things tack sharp.

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #27 on: May 10, 2014, 11:48:47 PM »
How are you focusing? Live view 10x? You should be able to get pretty accurate in-camera, especially with the short focal length of 105mm. Trying to focus through the viewfinder is pretty much impossible. I can't even do that with my 600mm lens. I either use live view at 10x zoom, or I use BackyardEOS in it's focusing mode while tethered to the camera.

I used 10x live fiew and manual focusing, turning the ring as slowly as possible.

Well, that's the right technique. Are you having trouble because the camera is shaking? Sometimes it actually helps to pretty much grab the whole rig, and balance it against yourself with as much surface area as possible. When the camera just kind of hangs free, it is sometimes actually more susceptible to wild shake than if it is being actively balanced by you. You'll still have some shake, but it should be slower and less problematic for your focusing.

BackyardEOS is a program that runs on a laptop or Windows 8 tablet that has a focusing mode that can control the lens' focus group directly. It has fast, medium, and slow controls, and it's actually the best way to focus DSLRs. The program costs about $50, but I've found it to be completely invaluable, especially for focusing my DSLR for astrophotography. If you can't get your focusing figured out using live view and 10x zoom, and are serious enough to spend the fifty bucks, BYEOS will definitely do the trick.

Shake wasn't an issue, as I said before, the Sigma's focusing ring is just not good enough for slow/steady turning. I have already looked at Backyard EOS before and it is a very nice program. The 2 shots I have were just quick/rushed ones I did a few hours ago, just step up the tripod, kept it stable, point at object, focus and take the images.

If it really is the manual focus ring, then BYEOS might just do the trick. It focuses electronically, so the build quality of the manual focus ring really doesn't matter. If the lens focuses well when using AF, then you would have very fine grained control with BYEOS. You should be able to get things tack sharp.

Okay!
7D | 24-70mm F2.8 I | 50mm F1.8 II

canon rumors FORUM

Re: jrista et al, Why Astrophotography?
« Reply #27 on: May 10, 2014, 11:48:47 PM »

jrista

  • Canon EF 400mm f/2.8L IS II
  • *********
  • Posts: 4814
  • EOL
    • View Profile
    • Nature Photography
Re: jrista et al, Why Astrophotography?
« Reply #28 on: May 11, 2014, 01:12:56 AM »
Here is an example of how sharp you can get the moon with BYEOS:





This is effectively perfect focus. The fine-grained controls in BYEOS allowed me to find the exact focal plane where the moon sharpened up to maximum. One tiny step forward or back, and things got visibly less sharp and atmospheric turbulence was visibly worse. IMO, even if all you do is shoot the moon, BYEOS is totally worth the money. :P

It also has a planetary imaging mode that will take video clips, automatically string them together, and offers a few other features (such as 10x zoom video, which when the planet only fills a tiny area of the sensor, can be quite useful).

traingineer

  • EOS M2
  • ****
  • Posts: 193
    • View Profile
Re: jrista et al, Why Astrophotography?
« Reply #29 on: May 11, 2014, 11:33:19 PM »
You know, why don't you get the Planewave 0.7m CDK Telescope System? Seems like a good option for 200,000$
7D | 24-70mm F2.8 I | 50mm F1.8 II

canon rumors FORUM

Re: jrista et al, Why Astrophotography?
« Reply #29 on: May 11, 2014, 11:33:19 PM »