Cheaper Astro-Imaging

Nov 2020


Without stating the obvious, there is a lot of stuff we buy that's imported by the US Dollar which comes from China. It's mostly single source too, so hunting for a new bargain is folly, as dealers work from the same price list. Equally, there's a huge amount of stuff for sale secondhand, since COVID-19 made astronomy the lockdown hobby of 2020. Apart from your local astronomy clubs there's also the Facebook groups, Astro Buy/Sell UK and companies like ENS Optical.

Then, there's Us.

If you think about it, there are literally tens of thousands of computerised EQ mounts in the UK (and across Europe too). It's possible to pick up a bargain, but HEQ5 and EQ6 mounts can be pricey secondhand, (sorry, not sorry) so they should be circa £450-£600 for an HEQ5, and £500-£700 for an NEQ6 dependant on age or condition. It's still worth going down this route and sending us the mount for a once over, as well as tuning it to extract more performance. It's likely that the mount is several years old and while it may be an improvement on the one you've already got, like a secondhand car it won't be as good as the one in the showroom.

If it's not been serviced or rebuilt and sold as a 'tuned' mount then do check for damage. Especially on the EQ6 around by the RA collar behind the polar-scope. If there are teeth marks from a strap, or, if you get a chance to take out the polarscope, check the end of the shaft. They're often hit by a hammer. Hard. Very Hard. Not advised on what is a precision mount. Adjust price accordingly, or walk away.

The EQ3-2, EQ5-HEQ5-EQ6-NEQ6-AZEQ6GT are all popular, but older Meade LXD55/75 are not. Flaky electrics that don't do damp, and are now legacy products. Celestron's like the CG5-GT, AVX and CGems, can all be guided, and will certainly benefit from a QHY Polemaster. However, I've seen few successfully guide over 15 minutes and they are difficult to extract more performance from. Again, bit of logic and shameless plug, one of our StellarDrive or StellarTune Mounts do occasionally come up for sale, and even though they often attract a premium, they still outperform new mounts, even at 3-5 years after rebuild.

Secondhand iOptrons are a bit rarer in the UK, due to their numbers but their performance is unquestionable. The ZEQ25 does require care, as it suffers overcurrent issues, and needs careful balancing due its geometry. They are however, all interesting mounts. If you're lucky enough to bag a CEM25P, or CEM60 then it can be a very trusty steed.

Don't forget to check out webcams and older CCD's and CMOS cameras that work with PHD guiding and programmes like SharpCap. The cooled stuff is not cheap and normally kept for years, as it's so fast moving they date quickly. Increasingly, you'll find some of the old cameras do still work with Windows 10, do your own research on the drivers. Download the latest copy of PHD2, and see from the list what it runs, before you go out searching. Which ones, you ask? ZWO and QHY have the lions share of the low to mid range cameras, as its sensor control that dominates here as much as quantum efficiency.

Same with DSLR's, anything more than a Canon EOS 450D is ideal as a secondhand imaging camera. I have an EOS700D, which is perfect, as the flip-out screen is really useful, and you find this on the EOS600D onwards. Just remember it's the sensor you need, not the funky features, unless you're using it for daytime photography too. The venerable EOS40D is built like a tank, but the 50D is the one to have as it's more sensitive and 15.2Mp. Avoid the Canon EOS 7D Mark 1 however, as although it's a great day time camera (for sports especially), it's too noisy for astro work, but the MkII isn't, Full frame EOS 5D's are getting quite affordable too, if you want to get into full frame that is. Just be aware of vignetting on smaller scopes and focusers, certainly M48 adapters help. Bigger focuser are better. I'd check out Wexphotographic.com of MBP.com for latest prices and availability on used camera bodies, as well as London Camera Exchange.

Add an Astronomik CLS Clip-In filter to pull out detail under more light polluted skies, with greater contrast and nebulosity.

Laptops, yep, buy used. You won't cry if you drop it in the dark. Add Ram, SSD, new battery and a 12v to 19v adapter. Waste juice if you use voltage invertors. And, no you are collecting data, not processing, so don't need an Intel i7, with 32gb Ram, 3gb graphics and a 17" high-Rez screen, that you'll reverse over with your car.

Yes, it's a thing. OK? ;-)

Telescopes, what about them? That's another blog I've been penning as I know a lot about them too, and rebuild them sometimes. Oh yes. I tune telescopes too, but too much time building mounts stops play.