Cosmic Geoff

Why would you want 12v or 13.8 volt regulators/converters? I have run mounts directly from my LIFEPO4 power tank for years without incident. The actual output voltage versus discharge state of these batteries can be found on data sheets.

I have a Celestron LiFEPO4 power tank which already has USB ports built into it, not to mention handy red and white work-lights. Note that a "12v" LIFEPO4 battery will require a specialist battery charger - mine came with a 16 volt charger.

The quoted loadings exclude counterweights. For visual use, you can load the mount up to the rated load (e.g 9Kg for an Eq-5). I put a 203p Newtonian (which weighed 9Kg+) on an EQ-5 and it worked well enough for visual use. For imaging, one is recommended not to load the mount to its full capacity. I am now using the same mount for EAA with a 102mm Startravel (I had to buy a smaller counterweight), and that works well. The counterweights on an EQ mount do not weigh the same as the scope and accessories (usually less) as you can position the weights anywhere on the counterweight bar as required. The actual weight needed depends on the physics of levers (q.v.)

You do not need large aperture for imaging, unless you want to image small objects at large image scale. Look at the small refractors that some imagers use. Exposure time makes objects brighter.

Is this for visual or imaging use? The manufacturers may quote for visual use, or for both. Suggested loadings for imaging are much lower. An EQ-5 will take about 9Kg for visual use. I put a 200p Newt on an EQ-5 and it wasn't too bad (for visual use). Logically, if you look up the load capacity of an EQ3-2, the load capacity of your proposed combo with be somewhere between that figure and 9Kg (for visual use). If your aim is imaging with the 150PDS, then forget the EQ3-2 and start saving for a proper mount.

When I had that version of EQ5 I bought a 6 volt lead-acid battery and a charger (the latter intended for R/C gear). Given the ubiquity of 12v power sources you might consider a 12v-to-6v stepdown converter.

If you don't have the user manual for the CPC, you can download it. I have a smaller version, and find it particularly suited to planetary imaging, as well as general viewing. I have also used mine for imaging small planetary nebulae. I have fitted it with two finders, a red-dot for coarse aiming, and a 9x50 RACI finder for fine aiming. The Nexstar 'Precise Goto' menu item is very useful for locating smaller fainter objects. If you don't have a dew shield (essential in UK) you can buy or make one. (If you have deep pockets, a dew heater ring and black aluminium dew-shield are available. The metal dew-shield looks very smart - saw one at at astronomy show.) You can hook the mount (actually the handset) via cable to a laptop, which allows you to control the telescope via various programs. I suggest you read up on Celestron SCT material generally - this may uncover some useful topics and tips. Check out nexstarsite.com. Your mount or handset might benefit from a software upgrade, especially if the GPS doesn't work, but remember the engineer's old saw "If it ain't broke, don't try to fix it." 🙂

Depends what is causing the light pollution. Once upon a time, street-lighting used lamps that emitted a few narrow-band wavelengths easily filtered out. With modern white LEDs it's useless, except that a filter that costs more than your scope outfit might offer a slight improvement. If you are observing gaseous nebulae, narrow-band filters e.g 'OIII' will offer a distinct improvement.

What is your level of experience? What do you expect stars to look like? A star should look like a point of light, irrespective of the telescope's field of view, or the magnification. Anything else is scatter or diffraction in the optics. Maybe if you look for double stars or globular clusters or planetary nebulae you will find those of greater interest. The 10mm kit eyepieces are generally acknowledged not to be much good, and deserving of an upgrade of the same focal length.

You need an EOS to T2 adapter, and a T2 to scope adapter. It seems you already have the latter for the SCT. Some refractors have a T2 thread at the focuser. Seems your Swift has this, so you just need the aforementioned EOS to T2 adapter, and possibly a T2 spacer to get focus.

A 120mm APO and a HEQ5 + accessories would be a good setup. Assuming that this is the kind of scope you actually want. What are you going to do with it? Another thing to consider - keep a cool head and add up the new retail prices of all these items - it does not have to be exact. Another Sky watcher ED 120mm comes in at about £1400, and the HEQ5 is about £1000. If you think this offer is a bit too good to be true, don't part with any money till you have checked this out from all angles, and if possible gone to see the items yourself. As a guide, astro kit on good clean & working condition typically sells used for about 66% of the new price.

I don't have a freedom Find mount but I have a Sky-watcher EQ-5 Synscan and three Celestron Nexstar mounts. I've always preferred the Celestron software - it's a little easier to use and has one or two features that the Synscan doesn't. I have not felt the need of Freedom Find, as though it can take a while for the mount to slew round, I often have little idea where it's going to end up pointing.

I'd say the mount/tripod is inadequate. It might do for visual use but for deep sky imaging it is clearly inadequate. Some imagers use a smaller Newt than that, e.g. a 130PDS, on a much heavier mount (Heq5 or EQ6). By the way, one night I forgot to position the counterweight on my EEVA imaging rig and the EQ5 Synscan was apparently not affected at all.

The most practical solution would be to order a replacement 4/5 SE motherboard, which hopefully you can obtain from Celestron or their distributors. OTOH, if the "chips" are generic resistors, capacitors or diodes, you might be able to source suitable replacements on ebay. This assumes you have the capability of identifying and desoldering/soldering them yourself. If not, you would be better advised to buy the motherboard.

What is your budget? Is weight or bulk a constraint? You could add a Newtonian to that list. Why have you ruled out a Schmidt-Cassegrain? For planetary observing, the bigger the aperture, the better (seeing permitting).

Rather than rushing to buy anything you should take a step back and do two things: 1) Buy the books "Making Every Photon Count" by Steve Richards (a book on deep-sky imaging available from FLO) and "Guide to High Resolution Lunar & Planet Imaging" by Dave Eagle FRAS (see his website www.star-gazing.co.uk for distribution.) Depending on how much you understand of the contents, certain conclusions can be drawn... The investment of £20 +£10 here might save you much more money further down the line. 2) I understand that you already have a camera, and a small telescope. As others have suggested, put the camera on some sort of mount and try imaging the night sky with it. Then attach the camera to the telescope and try imaging something with the combination. Download some free software with which to process the results. After this experience you should have a better idea of what practical astrophotography is like. You will then have a much better idea what to buy in order to progress with the hobby than if you buy expensive kit blindly. The Advanced GT isn't a bad mount. It's obsolete, but similar to the current model AVX. "Scope" I assume refers to the C6, which is a handy scope to have but not a first choice if you want to image anything. The focal length is much too long for widefield and it's on the small side for planetary imaging. Note that you can generally download the user manual for any mount or mount/telescope retail bundle from the Internet. If you are not familiar with GoTo mounts, it would not hurt to download a manual and read it. The instruction manual for my EQ-5 Synscan mount runs to about 50 pages.

You probably need to read up on the techniques for planetary imaging. 🙂 The normal method is to take a short video, but a DSLR may not be well suited for this - serious planetary imagers use a large telescope with long focal length and a planetary camera that can take high-speed video and crop the region of interest.

If you want to image these in particular you should pay close attention to what telescope, camera, filters, mount etc and in what sky conditions the imagers you want to emulate operated. I have tried imaging both these objects from my Bortle 6 location with the gear mentioned above and the results were very poor.

To give you a pointer, for EAA I use a 102mm f5 achromat telescope, an ASI224MC camera and a EQ5 Synscan mount. (Partly because I had all this gear anyway) It works really well for quick images of anything that will fit in a 0.5 deg field, e.g smaller galaxies and various planetary nebulae. It is not much good for imaging planets (too small & focal length too short) or for really wide field images (all of M31), or for taking long exposure award winning images. If you all up the prices you will see this is over £1000 worth of kit, excluding the laptop. You do not need a large aperture for imaging - a bit of exposure time brightens things up marvellously - unless you want to image very small things at a high resolution. If you want to image anything you need a decent mount - you can always change the scope or the camera. You mention dso imaging with a large Newtonian in your initial post - that is not beginner stuff, and generally requires autoguiding. And check the prices of large chip cameras.

You shouldn't believe everything you read online. 🙂 Cutting the IR with visual pass filter and then adding a IR pass (and visual cut) filter is going to mean you don't pass much of anything. The only reason I can think of for using two filters together is to suppress an unwanted pass-band.

Definitely, yes. I found that with an ASI224MC camera, using an IR-pass filter gave sharper images on Saturn, but with an ASI462MC it fails to do so.

I doubt that it matters much which IR pass filter you use unless you have some advanced project in mind, rather than wanting to see what difference it makes. I use the IR pass filter from ZWO (850nm) that costs about £25. The longer wavelength pass filters may give greater suppression of atmospheric disturbance. Using an IR-pass filter should render the ADC much less necessary (or unnecessary), but if you are using a UV-IR cut filter and an IR pass filter in turn, leaving the ADC in place saves you the bother of removing kit and refocusing. In my case I just rotate the filter wheel.

I meant make your own elevated stand e.g with concrete blocks and put the Dob mount on top of it. Like a table-top Dob but on a larger scale. The 8" Newtonian is not 'far too big and heavy for a tripod'. You just have to buy a suitable mount and tripod (not cheap, alas), de-mount the Dob, fit it with tube rings and put it on the mount. In practice it would be less bother to sell the Dob on and buy another Newt with the suitable mount as a package. It's up to you to decide whether you want to do this and set up a heavy mount and tripod + tube assembly every time you use it, and pay out for a suitable mount (the most likely off the shelf solution would be a HEQ5 GoTo at around £1000) Or did you mean the 8" OTA is too big and heavy for you to lift to shoulder height? At the 8" size another option is to buy an 8" SCT with tripod mount (normally GoTo). In terms of weight, size etc this would be much more user-friendly than a Newtonian or Dob. Not cheap though.

A Maksutov would make a good planetary scope, if you are looking for something fairly small and manageable. You should be able to pick one with a mount that is within your budget. A 150mm PL Newtonian and mount might be within your budget, offering more aperture for the money but more bulky. None of these are likely to give you planetary views as good as you'd get with your 200mm Dob (and an elevated stand).

It might prove challenging, given the small field of view. But why would you want to platesolve, other than for imaging (small) deep space objects? I found that when imaging planetary nebulae etc with an 8" SCT and f6.3 focal reducer, the 'Precise GoTo' available on Celestron mounts was usually enough to get the object into the camera FOV.