fifeskies

Yes , they compensate for telescope optics such as vignetting and dust on the lenses. You should not move focus etc before taking the calibration frames as this would change the position of dust motes relative to the sensor.

Would help to know what you plan to put onto the mount. Ideal height for a 150 mm f10 refractor will not be the same as ideal height for a 300mm f4 Newtonian. You may need to think about all the scopes you have and work out what will work for all of them. Another factor would be the horizon you have from the dome, if you have trees/buildings restricting your view to over 15 degrees altitude this will affect the decision. Also remember to offset the pier so the dome centre is actually the mount axis crossover in Dec and RA , this is typically 100mm or so pier offset South for the majority of mounts in Northern hemisphere at Scottish Latitudes.

Just a cautionary note Useable battery capacity is diminished the colder the battery gets Either allow for the reduced capacity at low temperature or make some provision to keep the battery warm before (and during) use.

Another version of the Dob size image for you.

Early on with my hobby I used a 200p on an NEQ6 mount which works well if you can put up with the focuser ending up at inconvenient angles. (Easily solved by rotating the OTA in the mounting rings) Going from a dob you will need to also obtain the mounting rings and dovetail. It was actually a very good system , plenty aperture and you see a lot more in a session once the GoTo is aligned. I also used an EQ"5" type mount but it is on the limit for weight capacity, so the "6" range is far better. Overall however I would suggest that it is probably better to sell on the entire 200p dob and get something more suited to an EQ mount , Refractor/SCT/ Mak

Coolceramic solar wedge from a member on here. Wonder when the sun will come back 🤔

SynscanInit 2 for Android - APK Download (apkpure.com)

I found this star test helps to set the correct backfocus

a 4x/5x barlow will be a wobbly nightmare on a manual mount, and will be just a fuzzy mess. The 2.5 powermate will give you not too bad zoomed in views, but use video capture best frame stacking to generate the best still image. (lots of youtube tutorials on this)

The OP profile puts him in Australia , so unless your friend is also in Australia its probably impractical to freight from UK (I know that location cant be seen when viewing forum on smartphones)

I used to have a 200P , I used it with DSLR , to enable enough infocus the barrel on my one unscrewed into 2 parts. Remove the eyepiece holder from the outer part and screw it into just the first section. (I used a 2 in eyepiece adapter on my DSLR) It was not obvious that the focuser barrel had the split as the join only leaves a very thin line. That said there seem to be many versions of the 200P maybe older models only have the one piece barrel. My 200P also included the T mount you could screw in as an alternative to the eyepiece holder , but it means you lose the ability to rotate the camera for framing.

Dew straps can adjust across a range of sizes with the velcro tags , slightly bigger is better than slightly smaller I would suggest. Just overlap at the "join" and all will be fine. You do need to have a power controller though , flat out they get a bit hot if it is not a frosty night.

I would run 2 cables from your 30amp supply, it is not the supply that is the issue but the voltage drop along the cable. Use one cable ONLY for the mount. The rest of the gear is fairly intolerant to minor voltage changes, the ZWO cameras regulate internally and the dew heaters are not at all troubled by any dip. They can all share the other cable.

William Optics GT81 Mk4 , a good step up from your Redcat Needs the matched reducer (0.8) and this reduces native 478mm to 382mm, just outside the range you mentioned but its a top class performer for widefield. Very portable too. Use the astronomy.tools visualiser to see how it works for you. I have the 533mc camera and have added an example of my imaging with the GT81, your camera will show more. Elephants Trunk Nebula , and the North America Nebula

Thank you FLO L-Extreme delivered fast, arrived Saturday and there were NO clouds in the box How well does it work, well here is my 2nd try with it , moon was almost full (97-98%) Image just stretched data with no other processing. (that's for rainy day entertainment to clean it up).

ZWO UV/IR on my 290mm mini guidecam did make the stars a whole lot tighter. With PHD2 multi-star guiding it is hard to say if it changed the accuracy. I got the filter 2nd hand so wasn't a big outlay and the guide cam monitor window is much clearer.

copied text below, can only imagine the effort needed to get that to slew in azimuth with 1845 technology. Great photo set from Nicola , would love to visit it. The tube is supported at the mirror end by a "universal joint", a hinge with two axes, which allows the tube to be inclined through a large range of altitude and also to be turned through a limited range of azimuth. The azimuth range is limited to about one hour by the supporting walls that flank the tube on its eastern and western sides.

Google tells me it did have some azimuth adjustment. 1hr only (15 degrees), primarily restricted by the side walls.

Since the OP gets good views with his other eyepiece it is hopefully not the case that the scope is out of collimation. As Tiny Clanger suggests though, take a good look at the 8mm eyepiece as it s all too easy to get a fingerprint smudge that may not be easy to see from the outside but can ruin the view through it, and it is still possible there is a fault of some kind. Only use a proper lens cleaning method, not the "t-shirt wipe" method as that will just make things worse. 🙀 You have a fairly travel friendly scope , so the 8mm may come into its own if you take it to a dark holiday site especially somewhere at altitude. (The caldera (crater) at 10,000 ft in Tenerife at night as mentioned previously is a stunning place to go for near perfect darkness and superb seeing)

your scope is 1300mm focal length the 8mm eyepiece gives x 162.5 magnification. This is very high magnification and will only really be giving you a clear image if the sky is very calm and settled. Typically this will need you to have a very calm night and the telescope given an hour or so to settle down to ambient outdoor temperature. This kind of magnification also requires a heavy duty solid mount, most small tripods will struggle to achieve this level of magnification. There will also need to be nothing in the direction you are looking at that produces heat haze , such as looking over buildings or a car park cooling from the sun heating it during the day. Any turbulence due to gusty winds makes that kind of magnification impractical. also for a non goto mount the tiny piece of sky the 8mm gives you in this particular scope will make finding and staying on a target challenging for beginners This all assumes you are in the UK, if you are at altitude such as the thin air of the crater floor at 10,000 ft in Tenerife it is a different story. With my scopes I tend to use 80 to 100x as the highest clear magnification most nights, and if it is extra extra good conditions I may push it to 150x. ( the kind of conditions you only get a few times each winter) with acclimatised scopes on a cold clear winters night in the early hours when the seeing tends to be best it may just be possible to push it further, though typically it is premium refractors that can go the extra magnification. Looking at Jupiter last night for example , with my 4 inch ED refractor the view at 130x had become mushy while lower powers seemed far superior. I think you have just got the wrong match to your scope with the 8mm, a 12mm (x108) or probably better 15mm (x87) will work best. (the 8mm is more suited to scopes under 800mm focal length) Get hold of a 15mm and you will get far better results from what is a very capable little scope. The 15mm also lets you see far more sky than the 8mm does, there are a lot of great targets that will match your scope and 15mm field of view. Below is view you should get of M81 with the 2 eyepiece options. the 15mm eyepiece is the better fit for seeing the whole moon at once in your scope. The 12mm doesn't leave enough space round the edge to appreciate it properly. If you only have this scope you can always sell on the 8mm, they sell fairly easily.

Inside my ROR I use a barbeque cover I got from eBay to cover the pier, mount and scope with cameras. Quite oversized but just the thing to keep the gear all enclosed to help keep any damp or dust out. With some heat from below this would work well I think.

I fitted this to my GT81, think it is very similar to the GT71 take a look at my photo guide to the process

I assume not as it is just a resistive load and the voltage is too low to be a problem if reversed

"can anyone tell me the EQ6-R base diameter that I need to look out for ?" NEQ6 / EQ6_R base info

Thanks once again to FLO A Baader low profile 1.25 to 2 inch adapter. (this has a slim 1mm deep shoulder) These actually have 3 plastic screws around the circumference as well as the grub screw lock for permanent mounting. (the thumbscrew can be removed when used in this way) Needed this as one of my scopes did not have enough in-travel for my Delos 14 when used with a 2 inch WO diagonal (using the reducer supplied with the diagonal) Shoulder on most reducers is around 8 to 10mm. All solved now