pipnina

My process for setting up my HEQ5 is as follows: Deadlift the mount & tripod to the spot where I will be imaging, and put it down with no payload where it is roughly pointing in the direction of polaris. What I like to do here, is make sure the mount is relatively well lined up with the tripod leg that faces north. If it's miles off it makes my next step a bit harder, but still possible. I stand back a bit, line up the mount with that north facing leg in my vision (so you look up from the ground, to the leg, to the mount). I then put both my hands together and point at the tripod leg, then almost lean back and raise my arms til I reach polaris altitude. If polaris is far to my left or right, I need to pick up the mount and turn it a bit! Then I put my body weight on the mount to get it to sink into the grass a bit (no hard ground sadly) and do that prayer-looking check again. If my hands run through polaris, I am relatively close and can 100% see polaris in the polar scope! (I have my altitude set for my location, I guess the first time you need your altitude set to relatively near your geographic laittiude) After I do this, it's just a bit of fine-tuning to put polaris in the right spot in the polar scope, or run a computer polar alignment check. Getting the hang of setting up and using an EQ mount is certainly one of the big hurdles we all struggle with at first. But once it clicks... You end up wondering what all the stress was about in the first place! I promise!

Sadly not. I could pick one up but as Pixies said I'd end up with the same 50 deg afov and quite narrow total field of view. That said, my glasses make wide afov viewing rather hard as wide afov EPs tend to have less eye relief : ( I could look at maybe a 5mm baader hyperion, although sadly I'd have to go straight to 240x or only improve my mag at 150x with that option, but they are on a sale at the moment for £106.

I should make a point of viewing mars this winter... But it seems to be sinking a bit and I'm not sure if my current eyepiece set is planetary optimised? I currently have a 10mm vixen SLV (which is quite nice) as my highest power EP. With my 10" dob I get ~120x mag with that but even jupiter looks a tad small still at that power. That said, going too high power might make it more difficult, as I find it hard to nudge my dob all that delicately...

That's a sharp pic, atmosphere must have been treating you well : P

I can still see it like this But maybe the listing has closed?

I know you've already been linked to AliExpress, but I bought mine from Ebay (mono ver) for £1250 and no import taxes were charged. https://www.ebay.co.uk/itm/144142406109 Select 26mp AR glass for the mono version. I think the OSC isn't so good as the "IR glass" is like the filter that blocks H-alpha for DSLRs. Maybe it's removable though?

Clouds are a bit dodgy here and there, but pictures are about to start rolling in for me! Sadly something still isn't right with the scope, despite recent works, but it may just be backspacing or even need for a higher quality flattener...

In fact, we can even take some relief that the global cloud cover is so bad right now, even Paranal observatory is clouded out slightly! (they have over 300 clear nights a year!)

I've had one or two semi-ok opportunities recently, tonight even could have been one, and possibly tomorrow. Sadly, what with the outdoor humidity being 95%, anything outside starts dripping almost instantly... And the dew heaters I ordered two+ weeks back still haven't dispatched! Amazon has chemical hand warmer packs though, and while I despise single-use waste, I feel a need to have *something* to keep my scope dry! I'm also patiently waiting for a change to use the skywatcher OIII and UHC filters I received at the same time I ordered the dew heaters and focuser replacement for my refractor. Hoping to spot the horsy this winter, and the NAN before time runs out as it is sinking! Mind, if we wanted good weather, we'd pretty much have to move to a mountain range desert somewhere... There aren't many places on earth (where humans live) that AREN'T cloudy right now! (as per https://darksky.net/forecast/40.7127,-74.0059/si12/en)

Thankfully the scope has an extendable shield built in, with a velour-like flocking fabric lining it. It's about a foot long away from the lens cell, but it does still fog up above 80% RH. At least the hair dryer is safe, maybe I could pack something warm in the gap between the cell and the dew shield? Not sure what to use though as water (i.e. in a flannel) holds heat but will cool down fast, and cause condensation when it does so... Maybe I can see if any shops near me have chemical hand warmers?

I've done some upgrades to my scope (focuser etc) and am itching to get some first light with the improvements. Sadly, the humidity is going to be up to 95% with the clear weather coming soon, and the dew heater straps were out of stock so I still need to wait for my order to be dispatched. Are there any emergency makeshift anti-dew measures I can take to get me through two nights? Jig a hair dryer to point at the scope? Heat up towels and tie them to the dew shield? I dunno, but it's going to fog up immediately if I can't do something : ( I have a tiny tiny dew heater that I bought for my DSLR, which could cover my guide scope, but the main scope is troubling me...

Re: Foam. My dad made a carry cradle out of a piece of composite board and the Styrofoam that was in my SW 250PX dob's delivery box. It's worked quite well and always holds the scope nice and snug for car travel! That scope doesn't hold primary collimation very well but is solid enough on the secondary, I use a laser at the start of each observing session to quickly get the primary right and it only takes me a minute or two to be happy.

I can't find much about the VX myself either. But I can find a video comparing the 130P-DS (I thought a decent little scope when I owned one) to an orion CT10, which is admittedly more expensive than the VX12, but I'm not yet sure of all the differences. I imagine the carbon fiber would make up the majority of the price uplift for the CT10... I don't know how much this helps, but I hope it does help somehow!

Can you post a raw file or use the PixInsight abberation inspector tool to let us see the center of frame, and the four corners easily? Some of the stars look like their core is off enter, which might be coma?

Could you include a more face-on image of the mirror please? It looks like it might only be dirty, in which case not much action is required. At most you could get away with rinsing a warm tap over it, then using cotton buds and distilled water, using single-direction and single-use strokes. Change cotton bud with every wipe.

I'm looking at the lynx astro drew straps (0.8 or 1a at 12v depending on size I need) and wondering if I need to put them on the inside or outside of the dew shield. There's a pretty big gap between the dew shield and the lens cell, so I don't know if I need the heaters on the cell inside the shield or on the outside of the shield near the cell when the shield is extended? It's an easier choice for the guidescope because the dew shield is metal and already connected to the lens cell, but the main telescope is a bit confusing to me. Especially since the type of carbon fiber it's made of feels like an insulating plastic more than a conductive metal. Do i need to worry, can I just strap it to the outside of the shield? How does yours work? It regularly gets to 80 or even 90% RH so even my newtonian primary and secondary got wet this summer. Cheers!

I might be wrong, but as I've come to understand it, don't cassegraine telescopes find it much easier to cover larger sensors as the OTA primary diameter increases? Say a 6" RC can cover a 30mm APS-C circle acceptably, but using the same design and scaling it up to a 12" RC you could cover a full-frame sensor just as easily with the same illumination and field sharpness across the sensor? I've noticed on scopes that actually list it in the sales page, that big ones (like the planewave DKs) can list very very larger sensor size coverage on the big scopes, and monster sized scopes like JWST have enough real estate in terms of field of view to have 10 sensors fit inside of that useful FOV (admittedly it is a whole different and more complex 3-mirror anastigmat but still)

Hi and welcome to the forum! The reducer has a male M48 thread, but the camera is C-mount which has a 1 inch imperial thread, so they won't mesh together without some sort of adapter. You will need this adapter to thread the camera into: https://www.firstlightoptics.com/adapters/astro-essentials-low-profile-female-t-thread-to-male-c-thread-adapter.html And this adapter to step the first adapter's thread size up from M42 to M48. https://www.firstlightoptics.com/adapters/astro-essentials-m48-to-m42-t2-adapter.html These add 8+6.5mm to the spacing between camera and corrector, and since the camera itself has 12.5mm that brings us up to 27mm, but needing 55. So we need this set of extension pieces: https://www.firstlightoptics.com/adapters/astro-essentials-m48-extension-tube-set-4mm-5mm-6mm-7mm-8mm-9mm.html 9mm, plus 8mm plus 7mm plus 4mm on top of our 27mm = 55mm back focus! Hope this helps! Won't hurt to throw the people at firstlight optics an email to check and make sure those are definitely the right parts for the job, but it all makes sense to me as-is! Hope you get the best from your kit!

This looks like a more dramatic issue to me than backspacing... Are there any bright light sources near the telescope when it is taking images?

Update: Worked with two guys in work today on machining the existing flange. Machinist reckoned only 13~mm of depth could be achieved before we went through, so it was going to be a bit close! Thankfully there was enough depth and now the m117 tilt adapter is threaded onto the rear flange, and looks pretty tidy doing so! And after all the kerfuffle about cutting the flange off... I chipped the carbon out with fox wedges, screwdrivers etc, only to discover that it WAS threaded onto the carbon fiber all along! It was just stuck better than I could grip it to twist. Thankfully the outside of the carbon tube is soft enough that the flange can re-start a new thread for itself, so it is basically already re-attached without the need for glue or resin! Om the downside, there is a LOT of carbon fiber dust to clean off of the objective lens and the inside of the tube... I think tomorrow I will be spending some time with the vacuum and dabbing the inside and the objective with damp cloth to remove it before I use some lens cleaner and microfiber to clean the lens cell properly. All seems to be going to plan! I get paid and can buy the focuser on Monday, so I hope to recommission the scope very soon!

I agree your information should have been enough from a customer point of view. But the only problem is the machinist doesn't have access to the part you're mating the adapter to, so they can only go by the drawing. I'd probably look up a fits table, find a tight-ish clearance fit, and slap those tolerances onto your drawing.

That looks sharp! I'd be pleased for sure!

That's one long extender! 😜 I found on my frac that they have a lot of backfocus, I presume because most are designed with reducers and diagonals in mind. I think a good test to see if you are going to see vignetting is to look down the scope, and if you can see the whole camera sensor from the corner of the objective lens, you're not going to see any vignetting! I think you can find camera rotators (Maybe like this one, but this is bigger than M42 thread https://www.firstlightoptics.com/williams-optics-focusers/william-optics-camera-angle-rotator-for-25-m63-focuser.html) so that could be an option here. I think for the modest size of the IMX585 31mm filters should be perfectly fine, so something like a filter drawer should work fine here: https://www.firstlightoptics.com/zwo-accessories/zwo-2-filter-drawer-m42-m48.html. This is, again, a bit big but you get the idea! Adding items like these to fit your current extension might bring you into focus, depending on how much further out you need to be? Hope this helps a bit.

That's pretty good! I wasn't aware full frame sensors could work on these newts- my APS-C sensor already had 33% vignette on the TS-GPU corrector and 25% on the MPCC MKIII What does a flat here look like, out of interest?

I sent them an email last week and they never responded, so I presumed they either didn't speak english or were disgusted at my german haha. Good luck with the service if you go that route! Let us know how it goes!