Shooting the Stars in Wyoming

imhotep wrote in post #5878890
What kind of mount are you thinking of using? The reason I ask is because the ONLY reason I was able to get away with using an EQ-1 for astrophotography is the extremely short FLs I'm working with here. Autoguiding is necessary for practically all long-exposure work on deep sky objects if you really want to get good results.

Hopefully the moderators won't mind this subject popping up in the Canon forums too. Keep the questions coming if you have them. I'm happy to help.

Curt,
Andromeda's size was one reason I selected it as a potential target. A shorter FL than would be required for some of the other DSOs. I figured some stacking of different exposures would be required. Fantastic image of the Orion Nebula! I'm envious (or perhaps motivated is a better way to say it). Someday!

Currently I only have an altitude/azimuth mount to work from so I still have declination errors to limit my exposures. However, I've been thinking about buying an inexpensive EQ mount. I have the same tripod so the 3/8" connection is great news. This would provide me with an interim solution until the hobby fund refreshes a bit.

Astrophotography is currently my next step for my combined photography/astronomy hobby(ies). My telescope inventory is limited right now to a small 60mm goto and a big 10inch Dobsonian - also with goto - neither of which is suitable for piggyback. I'm considering an Orion 102 ED on either a Skyview Pro or Sirius mount also from Orion. I'm not sure about the quality of Orion's small autoguider camera but that was also on my list of potential purchases with a small companion scope for guiding. At one time I thought about getting an Atlas and lashing my XT10 OTA to it but that seems too far fetched especially for astrophotography (can't imagine ever getting vibration or wind sensitivity out of that combination). You hit the nail on the head when you talked about how much money astrophotography can run - even entry level is pricey.

I'm also on Cloudy Nights. Excellence resource for any level but especially beginners.

Thanks moderators, for allowing the fringe discussion.

(PS - Curt, have you tried using a green laser for polar alignment? It gets you very close but for the final few seconds I'm guessing a more sophisticated process for alignment is needed. I'm inexperienced with EQ mounts so I'm uncertain how well the laser might work.)

WOW!!!! I have attempted this just this last weekend but I didn't have a motor drive thingy and even at 800 ISO the shots where hard to use. How did you get such low noise from a 240" 1600 ISO?

just awe inspiring......wow.

boblybill wrote in post #5881076
WOW!!!! I have attempted this just this last weekend but I didn't have a motor drive thingy and even at 800 ISO the shots where hard to use. How did you get such low noise from a 240" 1600 ISO?

In my case it was the low ambient temperature that kep the noise down. The camera had been normalizing outside for perhaps an hour before I shot those images and by then the temp was in the mid 40's.

Brian, good to know that you're already familiar with the CN community. You probably also know that, for better or worse, there are a lot of very knowledgeable and experienced people there. My tenedency is usually to just share my own experiences in hopes that it will benefit someone else. There are so many ways to get from A to B that I would never claim mine to be the "right" way. So definitely weigh all of the following against other oppinions and testimonials as you progress along the journey.

BigBadBrain wrote in post #5881037
Astrophotography is currently my next step for my combined photography/astronomy hobby(ies). My telescope inventory is limited right now to a small 60mm goto and a big 10inch Dobsonian - also with goto - neither of which is suitable for piggyback.

What is it about these scopes that poses a piggyback issue? I'm just curious because these two instruments sound like an ideal pair to get started with. For a long time I was shooting with a 70mm refractor riding piggyback on a very heavy 8" schmidt-newtonian. You can get piggyback kits that include rings and a bar that will fasten to many different types of OTA rings found on larger dobsonians like your 10". You could definitely use a 60mm/10" combo to climb the learning curve for awhile and figure out what you really want to use long term.

If you get the 102ED (awesome scope for the money by the way. I have the 80ED and it really surprised me) then you could easily use your 60mm as a guidescope for starters.

There are two Sirius mounts at the monthly imaging event I attend. One of my friends has taken some awesome images with two refractors mounted to the Sirius. A little known fact about is that the Sirius has the exact same drive that the Atlas does. The Atlas has more reinforcement in the drive housings and overall is stouter. It really depends on how heavy your scopes and cameras are.

The same friend I mention above is using the Q-guider on his TV-85 for autoguiding. It is a pretty nifty little camera and doubles as a very capable planetary imager. I"m currently autoguiding with a DSI Pro which is the only job I'll ever use it for. Sometimes I wish I had a Q-guider because you can find a color version that will shoot great planetary images.

That's my next step with the EQ-1. A green laser pointer that is carefully aligned with the RA axis will be more than accurate enough for SWA focal lengths. They're just fun to have around anyway. Here's an image of my buddy Carlos looking at Jupiter through a 12.5" dobsonian. The green laser is simply used as a finder on this scope.

http://picasaweb.googl​e.com …photo#520932535​7742497874

On polar-alignment in general, my first computerized mount was a Celestron CG-5 ASGT which I used to climb the learning curve for about a year. It's a very no-frills kind of mount but hard to beat for the money when you're just starting out. I have always used a freeware program called Polar Finder to get my alignment as close as possible without having to invest an hour in drift alignment (some people swear by it....but yuck). The user inputs their longitude, date and time and the software produces an image of where Polaris is relative to the NCP at that particular moment and location. Most polar scopes on popular mounts will have a crosshairs and then a little eyelet off to the side. If you use Polar Finder as a reference it is simply a matter of orienting the eyelet as seen on the laptop screen and then placeing polaris inside it. The NCP should now be very close the center of the crosshairs. This also assumes you've taken the time to align your polar scope to the RA axis before taking it into the field. I usually do this at home with a dot taped to the wall across my living room. In my experience this method will get you well within the capabilities of autoguiding to remove whatever error remains.

About EQ mounts - The EQ-G models (Sirius and Atlas) have some VERY nice ammenities in the polar alignment department. Both feature illuminated polar scopes as well as a screen that displays the relative locations of the big and little dippers as well as Cassiopeia. You see all of it just by putting your eye to the polar scope. This is arguably enough to get yourself within the capabilities of autoguiding to remove remaining error, but I still use Polar Finder with my Atlas anyway.

One final sales pitch and then I'll shut up. The Sirius is like $1200 new and the Atlas is $1500 new. IMHO the greater value is in the Atlas. Granted it is heavier and bulkier so take that into consideration. The Atlas can be found used on Astromart for around $1200 typically. BUT, the Sirius is still a great mount and if compactness/weight is an issue then it is significanlty lighter and smaller than its bigger brother.

Yikes, you guys have really got me talking now. Sorry about the dissertations. Feel free to send me PM's or keep this discussion going. I started this thread and I certainly don't mind talking about this stuff to anyone who is interested.

Wait. Are you saying everything from the tripod plate up was only $107? Got links to this stuff?

Your shots are beautiful. Now I will go back and read the rest of the thread.

I found the link to the mount and motor drive. Can you describe how do you set it up so it knows where true north is? I have some limited experience using equitorial mounts from my teen years, but it's been awhile. I suppose there are instructions somewhere?

Wow, something new to try. I even have the Tokina 12-24 and I think the same tripod your using.

canonloader wrote in post #5885602
Can you describe how do you set it up so it knows where true north is? I have some limited experience using equitorial mounts from my teen years, but it's been awhile. I suppose there are instructions somewhere?

Well, it's not much of a procedure compared to the ritual I go through on my main imaging rig. Let me photoshop a graphic real quick to make this more clear.

Byte size: ZERO | Content warning: NOT AN IMAGE

Thanks Curt, all very clear, and thanks. I use to be able to use a sextant too, so it all makessense. I will have to get out my old Mgellan and put some batteries in it and find out where I am here in La Crosse.

So if I got this right, once the angle is set, I line up the RA axis to NCP and fine tune it? Here's where I get lost. So once the camera center focus point is on NCP, then I can swivel the whole thing on the lower mount to any part of the sky?

I'm sure it will all make sense once I see the gear. I can't pass this up. I have everything else.

Great shots and great information. Thanks for sharing!

canonloader wrote in post #5886643
So if I got this right, once the angle is set, I line up the RA axis to NCP and fine tune it? Here's where I get lost. So once the camera center focus point is on NCP, then I can swivel the whole thing on the lower mount to any part of the sky?

Unfortunately this is all much clearer when shown rather than described. I think you are 99% there and the remaining 1% of understanding will come naturally when you have the mount in front of you. The beauty of these simple GEM mounts is how simple they are to operate. Everything is pretty much a bolt or screw to be turned that will set an adjustment.

This may make it a little clearer though.

1. Attach the EQ-1 to your tripod.

2. Set the tilt of the mount to match your longitude. NOTE: you're mount is now set in terms of up/down, but this won't be perfect for two big reasons - A) human error, and B) your tripod may not be perfectly level.

3. Pick up the tripod and turn it to aim the RA axis of your mount at the NCP. NOTE: your mount is now aimed in terms of right/left (i.e. east/west) but this won't be perfect for the same two reason given above in #2.

4. Now do a visual appraisal of your alignment and make any adjustments you deem necessary. This is hard without a polar scope installed inside the RA housing, which allows you to place your eyeball such that the imaginary line drawn through your mount's RA axis (And subsequently through the NCP) will literally pass into your eye and strike your retina. In our case we don't have that luxury and I feel guilty even writing about it. What I did was sort of wink with one eye and then the other while looking behind the RA axis. If polaris is being hidden by the backside of your RA housing while you are gazing in line with that axis, then that's as close as you can get with this sorry method. BUT, sorry or not, I got error-free images of 12-seconds at 28mm. A MUCH BETTER method would involve a green laser or red dot finder attached to the side of your RA housing that has been carefully calibrated to the center of your RA Axis's rotation. Again, this is what I'm goign to be doing in the future. If you can start out this way, do it.

Latitude?

OK, yes, I have the mental image of how to get the angle to Polaris. But now that it is, I want to shoot say a part of the Milky Way, to the South. This is where I am getting totally lost. And no doubt will have a duhhh moment as soon as I set up my mount on the tripod. What part of the mount turns the camera to that part of the sky?

I did PM you about the IR filter in your camera. I was wondering what the images will look like with the normal filters in digital cameras.

Your very helpful answering these questions, I am already buying my mount and drive, but not so much for star work, for the Northern Lights this winter.

Absolutely outstandingly fantastic shots. What is more impressive, is that you are taking the time out to teach the rest of us on how to take a shot like that. Thanks for sharing it with us. I'll be checking back to see what other tips you give us.

I am speechless! Just amazing.

My order just went in.

We'll be looking for those shots Mitch!