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mikeyL
member
Reged: 12/17/07
Posts: 22
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So I am a lurker who has read much, but not really done anything yet. Through a fortuitous coincidence, I have been working with a Paramount ME through some tasks on my job. Now for about a month, the mount is going to stand unused, and I have convinced my boss to let me piggyback my 40D and 70-200 f/4 IS onto the mount and try to image some things. I also have an 85 f/1.8, 50 f/1.8, and 10-22 if I wanted to try for some wide field stuff. The location is really in between a badly light polluted location and a really dark sky location. I have obstructions (the house) to the east, and some more significant light pollution to the south, and mountains to the west. I am very adept at driving the mount with TheSky software, and we have a pretty accurate and stable set up atm with the mount able to remain set up and having run a TPoint model to get our polar alignment to a reasonable value. So I am going to go up to the site this evening, and look at getting the camera and lens mounted. One last constraint is that I only have 2 camera batteries and no way to currently run the 40D off external power, so I will potentially have that to consider as well. On the plus side, I have a USB connection with extenders that should let me run the EOS utility on a separate computer right next to the mount control computer from the comfort of the garage, which should be prett cool. 
So what would be some reasonable targets to try, given the FOV of the lenses I have, and the time of year? I may get to experiment a little this evening even, but I mostly want to have everything optimized and set up to be ready by the coming new moon period (weather permitting of course).
I of course like deep sky stuff, but have no real magnification, so for that reason and for the reason of being a beginner I likely need to pick the right targets. I was thinking perhaps either M31, or perhaps M33 would be a good potential choice? Of course, I also don't really know a lot about what exposure subs to take, and what ISO might be the best compromise either. I have used DeepSkyStacker a little bit, so I will certainly be taking some dark frames to match whatever light frames I end up with.
So obviously, a bit of a strange situation with a newbie having access to a real high-end type mount, with no experience astroimaging, but lots of familiarity with my 40D in general. I am excited  , and don't want to waste this unique opportunity, so I am hoping to get some input from all the more experienced who have gone before 
Anyone want to chime in with a few ideas and guidelines?
Thanks bunches  ,
ML
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Jimmy2K63
Pooh-Bah
Reged: 04/26/09
Posts: 1184
Loc: Kentucky
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You will only have a short window to do imaging before the moon comes into play this evening but I think M31 sounds like a good one to try out. Just be sure and focus well, and that may be the biggest challenge so if you can, try to focus the camera on a distant object in daylight so you have a reference point to begin with. Good luck.
James
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http://astronomyguy63.blogspot.com/
LXD75 SN6-UHTC
Cave Astrola 10" f/5
Garrett 15x70/FarSight
Canon XS (1000D)
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mikeyL
member
Reged: 12/17/07
Posts: 22
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Thanks James! Ya, I know the moon is not my friend this evening  I was thinking to use live view to focus with - I have had some luck with that in the past although it can be a bit tricky at times. Assuming the camera mounting and cabling tasks get done in time I'll try to get some sort of an inifinity focus onto a far target while there is still some daylight, since I know from experience that if the focus starts too far off, live view can't really help much.
Thanks!
ML
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cdndob
professor emeritus
Reged: 07/28/06
Posts: 657
Loc: The Great White North
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You should be able to auto focus (use center spot) with the 70-200 on a bright star (vega, deneb, capella, etc) and that will get you real close or dead on. For future times look at making a Bahtinov Mask if you want to get it spot on.
I agree with James, M31 is a good target providing the light polution is low. Other targets you might consider depending on the time and moon position, M45, the double cluster, NGC7000, and the M42 area.
I'd be interested in seeing how the 85 does at 1.8, should get a lot of data in a short time using it wide open.
You probably shouldn't worry about the batteries, 2 gets me through an entire night on my 400d providing its not really cold out.
Hope you have fun your first time out and look forward to seeing the results!
Steve
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Falcon-
sage
Reged: 09/11/09
Posts: 240
Loc: Gambier Island, BC, Canada
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Rather nice to be able to start with a Paramount ME! That may spoil you, but at least you will have some of the common frustrations removed for the first couple attempts.
I am not much further along then you are, also shooting with just camera lenses, but I will try and give some advice...
For the two batteries - this is less of an issue then you think. I have an XT (350D) with two batteries in a battery-grip. I find that so long as I make sure they are fully charged up before heading out they last for quite a few hours of continuous shooting! Enough to get framed up, focused, and shoot at least one target with a good number of frames. One thing that makes a LARGE difference in battery time is the Review feature - turn it off! Go into the camera's settings and set Review Time to off so that it will not turn on the LCD on the back every single time it snaps an image.
For your 200mm M31 is certainly a good target. It is bright enough to let you capture it with fairly short exposures and large enough to be satisfying as a first target! I have not tried M33 myself but it is also of a nice size, and given your mount you should be able to play with longer exposures if it is faint for you. M42 is also a good target - being slightly larger then M33 and quite bright (but with lots of detail and faint bits too). I think because of the relative brightness I would start with M31 or M42 and then move on to fainter objects.
I recently got some excelent advice on how to use the histogram of a capture to determine minimum exposure time. You may find that handy.
As for focusing, you MAY be able to autofocus on one of the very bright stars, I understand some people have good success with that. As an alternative what I do is use now is an inexpensive application called Nebulosity rather then EOS utility as it has modes that help you get a nice sharp focus and will manage the capture series. It also of does stacking and processing of your series.
For ISO you are probably best of just sticking with ISO 1600 for your first attempt and playing with all the other settings.
As for number of frames - I would say you should go one of two ways. Either get a good focus and shoot 50+ exposures (if you want the best looking output possible), or shoot only 5-10 frames per series and mess with your settings (if you want to make it a learning/experimenting session). I managed to get this shot of M31 with only 10 frames (300mm lens, f/5.6) so you can still end up with nice results, just not as good as 50 frames would have been!
A tip to remember... putting the lens-cap on moves the lens enough to put you out of focus!
Hope some of this helps.
- Sean
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Tasco 11TE-5 'Lunagrosso': 4.5" Newtonian, 900mm f/7.9
Meade DS-2114S: 4.5" Newtonian, 1000mm f/8.8
Galileoscope: 50mm Achromatic Refractor, 500mm f/10
Tasco EQ-2-like mount w/ clock drive
Celestron CG-5GT mount
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cdndob
professor emeritus
Reged: 07/28/06
Posts: 657
Loc: The Great White North
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Quote:
A tip to remember... putting the lens-cap on moves the lens enough to put you out of focus!
Good general advice but the 70-200 is fixed length, focus and zoom are internal so no worries. I had good success with mine wide open but you can always try stopping it down a little. Now the 50 f/1.8 you basically have to tape the thing so the focus doesn't move.
Steve
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Falcon-
sage
Reged: 09/11/09
Posts: 240
Loc: Gambier Island, BC, Canada
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Fixed length! That is rather handy. Would have saved me some re-focus time a couple nights early on... (and most of the night's images the first time)
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Tasco 11TE-5 'Lunagrosso': 4.5" Newtonian, 900mm f/7.9
Meade DS-2114S: 4.5" Newtonian, 1000mm f/8.8
Galileoscope: 50mm Achromatic Refractor, 500mm f/10
Tasco EQ-2-like mount w/ clock drive
Celestron CG-5GT mount
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Ptarmigan
Carpal Tunnel
Reged: 09/23/04
Posts: 2351
Loc: Arctic
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Andromeda Galaxy
Double Cluster
Pleiades
Hyades
Orion Nebula
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Ptarmigans=Cute and Cuddly
Meade Starfinder 8
Nikon 10x50
Rebel XT
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mikeyL
member
Reged: 12/17/07
Posts: 22
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Sean,
Thanks very much for the fine reply, and the links. The link to Samir's site with his extremely helpful discussion on exposure times for subs and using the histogram was particularly enlightening (no pun intended  ) And I must say your M31 shot is very encouraging too!
Thanks,
ML
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mikeyL
member
Reged: 12/17/07
Posts: 22
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Thanks to everyone for all the good input. It would seem that my original idea of M31 would seem to be a good choice based on the consensus. I had not thought of The Pleiades - that would also be a decent first target as well.
Last night I was able to get the mount rebalanced with my camera mounted, but ran into problems with interfaces. In our work setup with the Paramount ME, we had been using a USB (with an extender) to control the mount, and we had another piece of equipment that was running over an RS-232 connection. The distance from the control computer to the mount was about 100 feet, so we had a USB extender for the mount and some RS-422 converters and dedicated cabling for the RS-232. My plan was to swap the mount over to the serial connection, and then to use the USB to run the camera. Unfortunately I could get neither of those interfaces to play. The serial connection to the mount did not work, perhaps because the the RS-422 converters are self powered of the RS-232 port (maybe it requires the presence of some RS-232 handshake lines to power it - I'm not sure of the Paramount RS-232 has this...) Not sure what the problem would have been for the 40D USB control over the extender, but it just didn't recognize the device. I had the 40D working over a conventional 10 foot USB cable with the EOS utility on Thursday night, so I know the software and drivers were installed ok.
I guess my fallback position of I can't get the interfaces to play will be to return the mount to USB control, and to use my intervalometer timer (a TC80N3 clone) to control the 40D. Not as slick, but better than nothing I guess.
I realize this may not be the right forum to ask this, but does anyone out there have any experience with either a Paramount ME running serial control, or with running a USB extender to control a Canon DSLR over the USB port?
ML
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