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Hi folks,
I am a new member of the BAA. I have a MeadeLX90 8” and a few basic cameras such as the Meade DSI colour and the Meade DSI pro. I have been limited in what I can do because of a back problem. Setting up takes forever, and polar alignment makes it even longer, impossibly longer. I would dearly love some advice on how I can make it easier to have a way of going outside and drop the telescope onto something and be up and running In a matter of a few minutes.
I have the field tripod the LX90 came with, I have since bought a wedge (not the superwedge), and I know I need to upgrade the setup, but am not sure how. I would be prepared to upgrade to a more expensive scope, but I realise its important that the mount has to come first. My primary interest is in DSO and planets.
I would dearly welcome advice.
Thank you,
Mike White.
I used a Meade LS-8 a couple of years ago. That was a case of shove it on the tripod, put tripod outside, plug in and flick switch. It handled all the leveling, north finding, GPS location/time and pointing refinement with an attached built in webcam. Failed 1 in 10 times and took about 10 mins.
You can take image of up to about 30s (threw away about 25% of pics) before field rotation trails the stars and its fine for planets. Got some quite nice pics with one using a Starlight H18.
Worth considering. Its doesnt get any easier – unless you go for a permanent set up. Richard Miles has an impressive solution…
Hi Mike,
I have a fork-mounted Meade LX90 8″ which I set up from scratch every session. I use it in Alt-Az mode (not mounted on a wedge) which means it takes just 20 minutes to set up and 2-star align to give perfect pointing accuracy. Like you I have a Meade DSI II colour camera with which I have done all the astrophotography you can see on my Facebook page https://www.facebook.com/hugh.astrophotography/photos_albums So a lot can be achieved using the easiest set-up.
Cheers
Hugh
Michael yo tengo un equipamiento de 8 ” pero aprendí de mis colegas que lo mas importante cual sea la marca y la potencia del equipo es conseguir una posición correcta para cualquier observación, yo termine por instalar una columna fija en mi patio con lo cual siempre estoy seguro de estar totalmente alineado y nivelado. Una vez que tengas eso vas a ganar en tiempo y calidad de un seguimiento correcto de lo que estas observando.
Suerte y buenos cielos
Leandro
Hello Mike,
It’s tricky to give precise advice without knowing a bit more about your observing ‘site’. Any kind of fixed pillar in a lawn, or backyard, can be a huge advantage, even if a crude observatory is not possible. Setting up each night is a huge hassle, even for someone without a bad back! Before the planets sank so low I used to do quite a bit of planetary imaging with a 12-inch Newt. on wheels.
See: http://martinmobberley.co.uk/images/Orion12inch_f5p3_mpm.JPGThe entire telescope just rolls out on a carpet from a wooden shelter attached to the house wall. After the telescope was polar aligned for the first time I knew by looking at the angle the base/wheels made with the lawn/paving slabs when the base was correctly aligned. In fact, under the carpet I made crude marks on the slabs indicating where the wheels should sit. This only guarantees polar alignment within a few degrees, but for 2 minute imaging runs on, say, Jupiter, it is more than good enough. Yes, you will get declination drift and a small amount of field rotation, BUT, compared to the problems of atmospheric seeing it will be negligible when the images are stacked with, say, AutoStackert! Deep Sky imaging is more of a problem (especially if you want to use accurate Go To) but, as Grant says, even with Alt-Az systems you can do very short exposures before field rotation trails the stars.
On a few occasions I used a small, fast, system on wheels to image big Deep Sky objects or comets like 17P/Holmes. This was a160mm f/3.6 Takahashi E160 on a Vixen Sphinx mount. See attached image…..
Occasionally this wheeled out on plastic rails, but on other occasions I just wheeled it around the lawn and literally ‘guessed’ the polar alignment by aiming the tube along the polar axis and getting Polaris centred. This was more than good enough for multiple 30 second exposures! If I was planning several sessions over a week I’d just leave the system outdoors covered with a tarpaulin!
Martin
There seem to be two issues here: weight (back problem) and setup time.
These are common problems. I deal with them in my book ‘Setting-up a Small Observatory’ (Springer), and we’ll deal with them again at the Equipment & Techniques Section meeting on 17 November.
I think you have 6 general choices, which address, or not, the two issues, in different ways:
- Leave the tripod and wedge outside, polar aligned, cover it with some sort of cover, and just move the telescope and other equipment in and out each night (may not address weight problem)
- Leave the telescope and tripod outside and cover it with some sort of cover or box, either flexible or rigid, that is completely removed when you observe (might address both problems)
- Build a proper observatory (addresses all problems in the long term, but may be difficult or expensive)
- Get a system that breaks down better into lighter components, maybe tripod, German equatorial mount with dovetail fitting, and optical tube (may not solve setup time problem)
- Get a smaller telescope (solves most problems, but not good for planets)
- Get a tracking alt-az or Dobsonian system (may not solve weight problem)
Damian Peach seems to leave his C-14 outside most of the time, just covering it over with a fabric cover, and it survives. In my experience this method results in corrosion, however, and of course you’ve got a big security problem. You still need to disconnect and take in all the camera etc. More of a proper shelter or box, such the one Richard Miles built, is better. This kind of solution, if well done, allows you to leave everything outside, including cameras, power supplies and wiring, and this saves an immense amount of time.
Nothing really beats an observatory for time-saving and back-saving convenience, and at the meeting on 17 Nov I’ll be describing a ‘An observatory from a £100 shed’.
But going back a stage, without building anything, you do mention polar alignment taking ‘impossibly longer’. Imaging planets does not require very accurate polar alignment, so I wonder if you are making too much of a meal of this. Increasingly also people are using the new CMOS-based cameras from companies like ZWO and Altair to do deep sky imaging in a more ‘planetary’ manner, using stacks of short exposures (1-10s). Then they really don’t need accurate polar alignment at all. In fact planetary imaging, and this sort of short-exposure imaging of brighter deep-sky objects, is possible with the tracking alt-az or Dobsonian system I mention as option 6.
There’s a lot to consider, and in the end only you can tell what your best convenience/performance/expenditure compromise is.
David
Director, Equipment & Techniques Section
Hi John.
For many years before I bought a Pulsar Dome I had my telescope mounted on a pier and used the TeleGizmos Telescope Cover which meant there was no need to lug it in and out of the house every clear night. The only thing then required was a)_ Polar alignment and b) to attach the cables.
With regard to a) this was easier as I had a polar alignment scope.
Hope this helps
Nick
Hello Mike
I have had a variety of telescopes over the years. Never having been able to justify to myself (and my wife!) establishing a permanent observatory, all have had to be set-up anew for each observing session. Some have had robust EQ mounts that almost brought on a back problem moving them! Others had GOTO systems which took even more time to operate than the basic setting up.
These telescopes spent a lot of time doing nothing (a familiar problem). In the end, I reverted to simplicity and bought a 200mm Dobsonian. Setting-up takes me a couple of minutes, the OTA is relatively light and manoeuvrable and is stored in a nearby shed. I have spent more time at the eyepiece with this telescope than all my previous instruments put together, mainly because it is so quick and easy to set up..
This will not necessarily prove an ideal choice for imaging. But if you want something easier than your current set-up, something that will increase your observing time and that will not endanger your health, you may like to consider it.
Good luck!
I support the Dobsonian suggestion though, as noted, it’s not suitable for long-exposure imaging. Lucky imaging of planerts should be fine as each exposure is so short that trailing is likely to be completely overwhelmed by the seeing and / or diffraction. (Maximum drift is 15 arcsec per sec for an equatorial target, or 0.15 arscec at a frame rate of 100 fps where you would need almost a one metre aperture for diffraction to be an issue.)
Indeed, back in the day I kept an 18″ Dob. in my kitchen. Made of plywood, it was still a reasonable task to lug its two sections out onto the back yard for an observing session. Current designs are lighter still. There is absolutely no way that a traditionally mounted 18-incher could be regarded as portable.
Planetary imaging with an undriven mount is very hard work because of the rate of drift at the high focal length used to get good resolution.
Robin
Thank you to everyone for their comments. I have a lot to learn and am grateful for all that advice. I am under light polluted Walsall (UK) skies and have to consider reaching a balance between affordability and reality in what can be achieved. I really do have a lot to learn, so thank you all for your comments.
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