Jay6879

This is good to hear! I ended up getting the gt81, it's a newer model that has the rotator built in. Unfortunately it looks like weeks of clouds ahead so Im not sure when I'll get to try it out! I also had a Zenithstar 61, fantastic scope that set me down the path of William Optics ownership. They make fantastic scopes. After that came the Zenithstar 81, and now I have the GT81. I just wish there was a 1x flattener for it!

Wow that's a stunning image! Nice stars, don't see any chromatic abberation, good detail on the galaxy. Ok this looks promising! Too bad William Optics doesn't make a 1x flattener for it.

Im looking at picking up a GT81 specifically for astrophotography. Looking for any impressions or opinions from people with experience? How doy ou like it? Is it a worthy upgrade over a doublet?

Could that have happened from being a bit heavy handed on the scnr?

I'm in Canada, and the integration was around 15hrs. I'd love to see what would be revealed by doubling that time! I'm still quote new to Pixinsight, only been using it for a few months now but i had posted the image during a "debate" on well corrected doublets (of which the Z81 would be considered one) and when I posted that pic the people on the uh...other side of the debate told me it was full of CA which I found bizarre haha. This was my first go at processing this object beginning to end and I'm definitely going to have another go at it and carry forward what I've learned. I'll certainly consider not pushing it so hard, and correcting the color! I appreciate all the responses!

I'm curious to see if others see any chromatic abberation, and if so would you consider it acceptable? I got thjs image using an asi533mc and a Zenithstar 81.

Haha I've never seen this one. You're right l, the jaunty music makes it. Some of the text killed me too. "Reslly get in there" "Egg whites contain a natural cleaning solvent" Edit - and him trying and failing to hang it off the clothesline 🤣

All I know is astronomy tends to be so...dry. There doesn't seem to be much humor or joking around (my numerous funny posts on cloudy nights with sweet gifs and stuff that wre constsntly being deleted is good proof) so when i stumed across this video this dude instsntly gained a subscriber..

My asi585mc just got delivered today coincidentally. I'll be using mine as a guide camera/planetary camera since I have a 533mc for dso stuff. The skies are actually clear tonight so I kinda want to try imaging Saturn and Jupiter with my Skymax 150. I'm also interested in doing a mosaic of the moon using the same Skymax 150. Judging by what astronomytools shows it'll be at least three panels which will be ridiculously high res.

Yes it's a flat61A. He is a screenshot from tonight after adding the other 21mm spacer.. And a link to the raw sub.. https://drive.google.com/file/d/1aztjkp9c_haXMsfYKMmv5UZW8yqVm2xV/view?usp=drivesdk Stars look way better!

Wait...no hold on. The camera already comes with an 11mm spacer threaded on. So the math would be.. 21mm+16.5mm+11mm+6.5mm(camera body to sensor)=55mm ZWO says to set the flattener at 12.9mm for dslr's, a dslr also requires 55mm of backfocus. So essentially I just need to add that other 21mm spacer (which I wasn't using before, only the 16.5mm and 11mm spacers) and I should be fine....right?

21mm spacer+16.5mm spacer+6.5mm camera body to sensor gets me to 44mm. 67.9mm-44mm=23.9mm So my flattener should be set to 23.9mm? Am I doing this math correctly?

Ah ok this is good info. The asi533 comes with a 16.5mm and 21mm spacer, and a few really thin spacers. I'll have to figure out the math to see if I need more spacers or not. Or maybe the adjustment on the flattener will provide enough that those two spacers will be good enough.

Oh yeah for sure, flats are always used. I'll look into a more heavy duty bulb, like a Rocket Blower. Zenithstar 61

Ok, so the dust is more likely to be on the flattener optics or further down at the end of the refractor then? Any tips on getting rid of stubborn dust? I've got one of those lens bulb things but it doesn't do much.

Ayy, the top image looks quite similar to mine. Ok, this is encouraging! I only used one of the spacers that came with the camera (16.5mm), I'll try attaching the other one that came with it (21mm iirc). I use astronomy tools all the time and never knew of this tool, I'm on mobile right now so it won't let me click and drag around the circles but I'm going to give this a go first chance I get. Geez, I literally took the camera out of the box, threaded in a 1.25" ircut filter and put it on the telescope! Though I guess it wouldn't take much for dust to hit the protective window on the sensor, even in that small amount of time. And no I don't have flats, by the time I got everything set up clouds rolled in. These were just some 5 minutes exposures taken on the preview screen of the asiair plus, then I just took a screenshot of them with my phone. The point of that test exposure was to see how far I could push my new belt modded heq5-pro, and the jury is still out on that until I can fix these spacing issues! Thanks for the quick replies, all is not lost! I dropped a decent chunk of change on the camera and got pretty freaked out by these issues, I never had anything with my t3i. Just pop it on and go.

First shots from my new 533mc. 300s preview exposure (beyond the star elongation at the bottom suggesting wrong backspacing?) what could these dark spots be? The weird thing is they weren't visible with a 5s exposure? They don't look quite like dust motes? And what is happening on the bottom half of the image? The stars are radiating away from the center of the image. Its happening at the top as well but not quite as bad. Is this a spacing issue? This was taken on a Zenithstar 61 with the 1.0x adjustable field flattener. Any help would be appreciated, this was my first night out in MONTHS. It took me awhile to aquire this camera and when the first test images came in I got pretty dejected with the results!

You were correct, at least for the lunar images. The asi224 with the Apex 102 is REALLY zoomed in. I tried my hand and creating a mosaic for the first time and it somewhat worked out..I had massive stacking artifacts on one panel that ruined the full image so I had to crop it and was left with this.. I also purchased a used (mint condition!) 2x Celestron Ultima SV barlow for thr planets later on in the season. Thanks again for the help!

Ah ok, I was hoping to get the images a little bigger with the bsrlow. What are the benefits of imaging at f/13 over f/26? Will it be not as sharp at f/26?

Welp....I completely bailed on everything I talked about in this thread. Instead I bought a wicked cheap used Orion Apex 102, an asi224mc and an ir cut filter. Just need a 2x barlow and I'm ready to rock!

Wow! That's crisp. Tons of detail. Alright you guys have essentially pushed me over the edge here, I think I'll pick it up. He's selling it for less than half the cost new, I'd like a larger aperture but for the price it seems like it can't be best. Later on down the line I'll upgrade. What equation are you using to determine the best f ratio for pixel size?

Wow that looks amazing considering it's a single shot! I can only imagine what could be produced with lucky imaging.

Yes I do guide with the zenithstar using an asi 120mm-mini. It's only black and white though, that would be kinda lame for planetary imaging no? As for lucky imaging two years ago I started this whole astronomy thing with a tabletop Starblast 4.5. Despite the objections from people over at cloudynights I stacked a 2x and a 3x barlow on top of each other then a neximage burst and got these images.. Completely unconventional sure but hey these images blew me away! They were a ton of work, line everything up in sharpcap, hit record for ten seconds or so until it crossed the frame. Move the scope and reorient the planet, hit record for ten seconds or so rinse repeat until I had 5 minutes or so worth of data. It was immensely rewarding though. So I have a basic understanding of lucky imaging, the processing I could use some more practice with though. This will be the first maksutov ive encountered so that's why I had these questions. Unfamiliar territory! I ousted that little starblast way outside it's comfort zone, was just curious where the edge of thay comfort zone lies with the c90. I appreciate you taking the time to reply, you've always been helpful! Also the link yubposted has no image? It looks like the link is broken?

Thanks for the replies, everything sounds good then. Zenithstar remains my wide field imaging scope, the c90 will become my lunar (and possibly some planetary?) scope. Good to hear that the c90 is a good little scope! And it plays well with a dslr? Just screw it into the t2 built into the rear and you're good to go? If I wanted to use a barlow with the dslr how would I go about that? And what would be the max barlow I should attempt for imaging do you think? 3x?

I have a Zenithstar 61ii and have used to to take a few images of nebula/andromeda etc but recently came across a great deal on a Celestron C90, he seems like a really cool dude and is selling it for $200 (new is almost $400cad). I'd use the C90 for planetary and lunar viewing but I'm mainly curious to know if the C90 would produce a better lunar image than the Zenithstar? I'd be using a t3i for now until I get a dedicated camera. Obviously the C90 would produce better images of the planets due to focal length but I'm not sure how to compare quality between scopes. Resolution? How is optical quality quantified? I'd appreciate any information on this, don't want to miss out on this sweet deal but would prefer to know if it's worth the purchase.