Backyard Space Dude

Not a problem at all, thanks for the comment! Here's a comparison on Cloudy Nights between Baader 7nm and Antlia 3nm: https://www.cloudynights.com/topic/749764-comparison-antlia-3nm-ha-filter-to-baader-7nm-ha-filter/?hl=%2Bantlia+%2B3nm#entry10839989

My pleasure! Glad to have helped.

Thank you all for your comments! Yes, I'm lead to believe the smaller artefacts around Alnitak are microlens issues with the ASI1600MM-P.

I recently purchased a set of SHO Antlia 3nm 1.25’ filters. Up until now, I’ve been using 7nm ZWO filters. Not having sold my ZWO filters yet, I thought it would be a good opportunity to compare the two. This will hopefully give prospective buyers a good idea of what to expect. Hopefully this is in the correct area of the forum! Like a lot of people, I simply can’t easily afford a set of 3nm Chroma or Astrodon filters, so having a set of 3nm filters at roughly half the price, with technical specifications that match the top-end brands is very enticing (I'm talking OD5). The data was all taken on the night of the 30th January, 2021 from my back garden. There was a 98% illuminated moon. Bortle class 4/5 with an estimated sky quality of 20.61. This data is according to the Clear Outside weather app, as I have no way of accurately recording this myself. Images shown here are in the format of .gif to better show the direct comparison, as I have found side by side images are difficult to differentiate. Each .gif scrolls through the 7nm image, then the 3nm image in 2 second intervals. I perhaps should have gathered more data on the Oiii filter, but that's hindsight now! I have also made an unboxing video, which you can watch here. (I'm new to video creating, and it also encompasses some beginner knowledge on narrowband filters, so you can skip through that bit!) I have supplied the original data with calibration frames available for download here. Let me know if you find anything interesting! Equipment Telescope - Skywatcher Esprit 100 & matching field flattener, Filter wheel - ZWO 1.25” EFW, Camera - ZWO ASI1600MM-P (Gain 139, -20C) Mount - Skywatcher NEQ6-P, Guiding - ZWO ASI174MM & Skywatcher finder scope, Acquisition - ASIAir Pro & iPad Pro, Calibration with Bias, Darks and Flats and registration performed in SiriL. All images had an auto-stretch applied in SiriL, exported as a 16-bit tiff and then converted to a .gif and resized in Photoshop. For an uncompressed true representation, feel free to download the original data from the link above. NGC 7822 - Ha - 1x600s NGC 1499 - Ha - 1x300s M 42 - Ha - 1x180s IC 2177 - Ha - 1x300s IC 1805 - Ha - 1x300s IC 1848 - Ha - 1x600s IC 410 - Ha - 1x180s B 33 - Ha - 1x300s B 33 - Oiii - 1x300s B 33 - Oiii - 1x30s Having never been exposed to 3nm filters before, I am probably not in the best place to make conclusions. I was initially taken back by the Oiii results, but I gather this is troublesome for most filters, and I would expect some negatives having paid half the price of brands like Astrodon and Chroma - perhaps someone would be able to provide some insight into this? However, I can't deny that I am very happy with the results and I'm looking forward to getting stuck into a new target ...as soon as the clouds clear!

Incredible images! I love the sunflower the best, the detail is so crisp!

Wow! I really like the colours. It's amazing to see different objects in relation to each other.

This was a couple of days ago. I've since done a little unboxing video, hopefully posting later today if anyones interested!

Hello all, I have a Skywatcher 200PDS that's gathered dust for years as I've always been a fan of refractors. I've gotten it out multiple times to try and collimate it, but I just can't seem to get it right. I fear that I've now played around with it so much that I can't get the secondary and primary back in line. The primary mirror is now absolutely covered in dust, too. I like the idea of being able to take it all apart, clean it, put it back together and collimate it - but I'm at a point now where every time I attempt to collimate it, I think I make it worse! Because of this, I now don't use it. But I don't want to sell it because I know it's a decent OTA with a different FL to my refractor, so it'll give me some nice options if I can get it up and running. My question is this - Is there an astronomy retailer/service provider (or even someone local to me!) that for a fee will take it in, clean it up and collimate it for me? Kind of like a car service if you will! I live in Ely, Cambridgeshire and I don't mind driving for an hour or so to get it done. Thanks, J

I've given up trying to get the back focus/tilt squared away on my Esprit 100/ApexED combo, so I've sent it back and ordered the standard SW flattener from FLO. Hopefully delivery won't be as long a wait as suggested on the website! Here's a couple of images I took when I needed a break from tearing my hair out. They're kind of first light with my Esprit 100 - though I'm not counting them as my real first light. NGC7635 - 26x300s Ha (7nm), NGC7000 - 6x600s Ha (7nm). Esprit 100, ApexED L, ASI 1600MM P.

Having been clouded out and stuck in isolation recently, I've been re-processing some old data. This was taken with a DSLR, and comprises about 10 hours data in Ha and Oiii. 10-minute subs. SW 80ED. Both the original and new process are attached. As much as I like the newer version, I can see where I'm over-processing and relying too much on noise reduction. It's all still a learning curve!

Thank you so much! Having access to new data at this standard over lockdown is such a blessing.

Congratulations! Some amazing entries indeed, I gained some good insight into different processing techniques and combinations. Thank you FLO so much for continuing to post data like this for free!

Soooo good. I prefer the orange/blue version - I strive for images of this quality!

Amazing, it's so smooth but so sharp!

Love it Carole. I'm having issues with the backfocus on my Esprit with the Starizona ApexED. Once I've got that squared away I'd be happy to get a first light as good as this!

Thanks all for the input! I used to use ImPPG, and it definitely gave great results! To be honest I totally forgot about it this time round, but I'm still very pleased with the results Topaz has given on this one. It's certainly the sharpest and least noisy image I've produced to date. When I get some free time I'll do it again using ImPPG instead to compare.

Hey everyone! It's been a while since I've managed any solar imaging, but I finally managed some yesterday! Wanted to share it here for my first solar post on SGL. I've got a lot to learn, I'd love some feedback and tips! SW Esprit 100, Quark Chromosphere, 174MM. Stacked in AS!3, process in Photoshop, used Topaz Denoise and Sharpen for the enhancements.

This is fantastic! Thank you so much for sharing this amazing data, I had a lot of fun processing it. My workflow was as follows: Small levels stretch of each channel individually, then ran through StarNet++, Imported the starless images into Photoshop and processed individually; Further levels stretch, Contrast boost in Curves, Blurred the surrounds of the main nebulosity using Gaussian blur and masks, Removed any artefacts left from the star removal using the spot healing brush, Removed noise and increased local contrast using Astronomy Tools and Annies Actions. Combined the edited starless images into SHO palette, Played around with selective colour, hue and saturation to fix the colours to my taste, Adjusted the contrast further with the curves tool, Added the edited Ha starless image as a luminance layer, Created the star layer; Combined the original images with their respective starless images using "difference" to remove all nebulosity and keep just the stars, Combined the stars into SHO palette, Ran dust and scratches noise reduction set at 2 pixels to reduce the stars, Removed the magenta and some of the green using selective colour. Combined the star layer using "screen"

If anyone finds themselves in my situation in the future I thought I'd make an update: I've spent about 6 nights trying to dial this in, and I can say it is a VERY delicate process. When I took delivery of the tilt adjuster, I could only find it going into place directly in front of the filter wheel - which was insane because I couldn't get to the adjustment screws. I figured out a slightly different place for it (behind the reducer) but I still had to take the entire optical train off of the telescope to make adjustments. Last night I spent about 6 hours with an extremely laborious process of continually: - Taking a test exposure to get correct focus - Taking an in-focus test exposure - Importing the test exposure into CCD inspector for analysis - Removing the optical train and making the adjustments on the tilt adjuster/adding or removing back focus - Putting the optical train back together and onto the 'scope - Repeat. I got close a couple of times (I presume to blind luck), but I found that I was over compensating as I didn't know just how critical the spacing had to be. For example, at one point I thought I had to simply bring the right side of the sensor further away, but ended up bringing the left side far closer in by doing so and the result was disheartening to say the least! My inexperience with this is really showing, but I'm determined to get round stars edge-to-edge. There are examples of people using the same setup as me and achieving amazing results, so I know it can be done. At around midnight I managed to get it as close as I could before giving up again. Here are the results (Centred on Caph): Preview_Caph_1s_Bin1_L_gain139_-18C.tif

Thanks Goran. A RASA would have been a fantastic purchase, but I chose to go with another refractor. I may yet choose to purchase the standard flattener from FLO for my Esprit, it's not that expensive. You never know, maybe in the future I'll get enough cash for two rigs! However, after drafting an email out to Starizona I decided to give it another go. I hadn't really gone about my troubleshooting methodically yet. So here I am, 4th night in and after a couple hours of different focal lengths, orientations, checking focus in each corner with a bahtinov mask and noting down my findings - I've gotten as close to it as I can. Top corners look good, lower corners look too far out. This is in all orientations - so it looks like I'll have to grab a little tilt adjuster from FLO to compensate for what seems to me to be sensor tilt. For the time being I'm happy, I've seen some decent results with this combination so I'm going to continue to work through!

Thanks Olly, that does help somewhat as it seems I might be chasing something that’s almost impossible to achieve. I certainly don’t have the patience for it as my attempt last night will validate! I repeatedly took the system apart and put it back together going up and down by one spacer/shim at a time. Although I did see a difference in star shape, I still couldn’t get each corner looking decent. I’ll attempt to speak to Starizona and see what they have to say.

Update: Last night I ensured good balance, tight screws and threads and good polar alignment. Star shapes were still about the same, even on a different area of the sky. They were all just a bit random as the night before. Having a closer look, it appeared that "cone" shaped stars where more present than anything, so I took that as too much length in the back focus and took out some of the spacer rings. The result was a back focus of roughly 57mm (1.5mm shorter than it should be). After taking an exposure I found more severe star shapes in the corners, but at least they all looked the same - possibly coma but I'm not sure that's technically correct (See attached image 1x 30s luminance). I stuck it through CCD inspector and found HUGE curvature, but at least the sensor was far more central (but still not perfect). To me, it looked like the back focus was far too short. At about 0130hrs this morning I gave up. After getting some sleep I took the optical path completely apart and tried to configure the OAG differently to allow me to thread the ApexED onto the focuser, rather than using the self centering thumb screws I'm currently using. Unfortunately the guide cam comes too close to the focuser to allow me to thread the adaptor on. I put it all back together as previously but carefully ensuring 58.6mm back focus - which should be absolutely spot on according to Starizona. I'm due some clear tonight, so I'll give it another go as it is. I'll also remove the guide cam and thread the reducer onto the focuser and see if that improves things. If it does I may have to look at a different OAG or use a finder/guider. If anyone has any input I'd greatly appreciate it! I'm kind of just fiddling aimlessly at the moment!

Thank you for the heads up on this software, it looks to be very powerful! If I'm reading this correctly it looks like I have some serious tilt? The darkest area looks to be in the bottom right. I'm not sure if the numbers are normal but it looks like there's more curvature than I'd have hoped for with the ApexED flattener/reducer?

Thanks for your reply! I've edited the OP to include the details as I realised I didn't exactly give much detail originally! All exposures where the same, at 600s. Thanks! I'm on a Mac so not sure it will work, but trying to work around it as we speak.

Hello all! Brand new SW Esprit 100 + Starizona ApexED L has been sitting gathering dust waiting for clear skies, until the other night where I could finally test it out. The back focus with the ApexED L and the Esprit 100 is 58mm, I've got that dialled in (including the +1mm optical length for the filter). I know there may be some slight differences in each optical system, but I can't quite figure out what's going on with my system. It looks like maybe I've got tilt as well as incorrect back focus. The astigmatism in each corner looks slightly different. To add to the confusion my guiding was terrible that night. I think I'll have to try again with better polar alignment and guiding, and tighten up the screws in the optical path! But it would be handy to get some pointers so I don't go in the wrong direction. Any advice from the great minds of SGL? EDIT: I realised I didn't exactly give much useful information! This is 1x 600s Ha (7nm) exposure taken with an ASI1600MM P. I took 6x 600s exposures, and they all show the same star shapes in all areas of the image, leading me to believe it's likely a result of somewhere in the optical path. Here's a crop of all 4 corners: