AnakChan

Despite having a new camera this year, I've hardly produced any images as most of the year has been on learning how to use the new toys. I thought I better produce one more image before the year end, and with the Horsehead Nebula in Bicolour. So here's my version of of it with Hα & Oiii taken in mid Dec. I wanted to capture in landscape to get the wall as much as possible but the flare from Alnitak is a bummer. I should probably should have framed it better. Image capture details are as follows :- Takahashi µ250CRS @ native 2500mm F10 Vixen AXD Mount ASI6200MM/EFW/ZWO filters -10C 100 Gain 50 Offset ASI174mm mini guide cam on ZWO OAG M68 63x 5 min Hα over 2 nights 48x 5 min Oiii over 2 night (Total 9.25hrs) 30x flats of each filter 30x flat dark matching for each filter flat 50x darks Acquisition managed by N.I.N.A.

Doh! I missed that...mine's F4.9. So actually thank you. This may prompt me to test by removing my reducer and try native 800mm/F6.4 to see if that helps.

Upgraded to the M68 tilt adapter :D. I'm pretty sure this is due to the ZWO 2" filters, since they're mounted, the actual filter glass itself is less than 2" naturally. But I am surprised at @gorann's 2" mounted Baader not vignetting at all.

This is the vignette I get with the ZWO 2" Lum with the ASI6200MM on the Pentax 125SDP which was surprising. the 125SDP should have an image circle the same as the FSQ106ED.

Yes, there's only 2 options for the ASI6200MM....the 2"x5 or 2"x7, I have the 2"x7. In this sample pix, it's attached to my Tak µ250CRS instead (which has a smaller imaging circle so vignette on this scope makes sense, but not on the Pentax 125SDP).

Thank you. That’s the same EFW2 2”x7 I use except in my case with ZWO filters. Well I hope when I move to unmounted filters, it won’t vignette.

Goran, Which filterwheel do you use with your ASI6200MM? I have the EFW2 with 2” mounted filters and it vignettes even with my Pentax 125SDP (88mm image circle). I’m looking at moving to unmounted 2” filters in hope that it doesn’t vignette - but spending thousands on 2” unmounted filters in hope is quite a big risk.

IMHO broadband filters are not going to be useful in Bortle 8-9 skies. If you're going to shorten the exposure to build an image, then you may as well ditch the broadband LP filter altogether and shoot without it. As mentioned in my post, one could even shoot over a thousand 30sec subs to build that image (that addresses the SNR you're referring to). But the OPs proposed camera is the ASI2600MC which is 50MB per sub. Integrating 1000x 50MB subs would be challenging nevertheless. It's true post processing could potentially address issues (gradients, etc.) however I would assume one would want to capture as many clean subs as they can to reduce the amount of post processing work.

IMHO, broadband in Bortle 8-9 isn't going to be useful. In Bortle 5-6, maybe a different story. Here's a test I did last year in my Bortle 5-6 skies. The setup is as such, Takahashi µ250CRS (2500mm/F10), CentralDS A7S cooled to -18C ambient, ISO2000, 5 min exposures. Most are with IDAS filters but with one STC filter :- 1) HEUIB-II is probably the widest band but as you can see it's washed out in just 5 mins 2) LPS-D1 was the replacement of the LPS-P2 which is a wide-band LPS filter 3) LPS-D2 was designed to cut out LED (although I'm not so keen on the green cast) 4) LPS-V4 which "back in the day" was somewhat a "narrowband" but by today's standards isn't very "narrow" 5) NB2-PM is an Ha/Oiii dual narrowband with approx 19nm & 21nm respectively 6) NB3-PM is a Oiii/Sii dual narrowband to compliment the NB2-PM. The NB3-PM has been replaced by the NB4-PM. The NB4-PM is a little narrower. 7) STC DuoNarrowband - IMHO, STC was the one who kicked off dual narrowband trend back in 2018. After that we see a plethora of dual/triple/quad narrowband filters. The STC DuoNarrowband is either 11 or 12nm You can see that even D1/D2 are kinda struggling under Bortle 5-6 as wideband LPS filters. I could shoot shorter exposures naturally. But if you're shooting under Bortle 8-9, IMHO you're better off just shooting NB, or (if you follow Cuiv, The Lazy Geek on Youtube) shoot many really shot 30 sec exposures and build your image that way. With my sensor, it's not practical for me to shoot thousands of short subs to process.

Has anyone noticed that “Clear Outside” no longer shows Day 5 to Day 10 (at least on iOS, don’t have Android)?

Thank you all for the kind words and words of encouragement. I have to say that when it comes to processing, I still don't know what I'm doing but just trying different workflows. I may see what I'm doing wrong in trying to fix the star colours. Prior to this I worked on OSC only and never tried (& never considered) splitting to separate mono channels.

Cheers. I tried hard to get rid of the magenta and I found some stars were able to remove easily whilst others (which you see), didn't. If I tried continuing to remove the magenta on the remaining stars, then the ones that had been removed would start to develop a blue halo. So after awhile, I stopped and left it. As mentioned, this is my first time trying SHO (or 1st time trying mono in fact), and I was inundated with the plethora of different workflows.

It's been a long while since I've posted in this forum. I've been imaging with a CentralDS A7S cooled mirrorless for the past 5 years through my Takahashi µ250CRS. This year I took the plunge into a proper dedicated astro camera with the ZWO ASI6200MM with the EFW2 2"x7, & OAG rig. As this is my intro to a proper dedicated astro camera, I took the easy way out of getting an ASIAir Pro as I have no portable PC to run SGP/N.I.N.A, and the ASIAir Pro was easier to learn than the the other two more sophisticated software. Despite having my rig in Feb, I had to sort out some teething backfocus and tilt issues which were difficult to troubleshoot. I finally got the right sized adapter earlier this month - it also means for the past 5 years I've been shooting with my A7S with an adapter backfocus of 5mm too short! As I live under Bortle 6 skies, I decided to try NB imaging for the first time and here's the SHO result. Specs are as follows :- Takahashi µ250CRS (2500mm/F10) Vixen AXD mount ASI6200MM/EFW2/ZWO 2" NB Filters ASI174MM Mini guide camera ZWO ASIAir Pro for Acquisition control Sensor Temp: -10C Gain: 0 (Offset 0) Bin: 1x1 Ha: 24x600sec (4 hrs) Oiii: 56x300sec (4.67 hrs) Sii: 30x600sec (5 hrs) Darks/Flats/FlatDarks: 50 subs Total Integration: 13.67 hrs Processed in PixInsight 1.8.8-5

So, no I don't have direct experience of using the PCB-EQ2/3 on its own without the counterbalance - once having the PCB-EQ2/3, it just makes sense to have the counterbalance.. You may have a point that the payload offset that is further away from the axis, however having used the Polarie and the PCB-EQ2/3, I feel there is a higher chance achieving consistency with a loaded Polarie that is polar aligned despite the payload offset. An alternative is to have the polar align scope offset, then you can have both a loaded std Polarie setup, and the guide scope that's off-axis on a bracket. https://www.365astronomy.com/Lacerta-Illuminated-Polarscope-with-Off-Axis-Holder-for-Vixen-Polarie.html

Correct, and that's where the "consistency" operative word comes in. Bear in mind that aside from just load, there's balance, etc at play too. The Borg 45 is 380g whilst the Canon 200L/2.8 is 765g. Will you have a collar around your Canon so that you can mount it to the ball head there, or will your camera base be the mount point? Even if you don't want to use a counterbalance system, I think having something like this (http://www.uctrade-shop.com/image_used/vixen_polarie_set_01.jpg) so that you can use a polar align scope with your camera mounted, I think will help in giving you better consistency for over 1 min subs.

200mm consistently esp without a polar scope attached after the camera is mounted? I’d have to say “No” unless folks an extremely tight setup - by this I mean a wedge/tripod that is really firm and no chance of movement when you put on the ballhead & camera. What kinda exposure durations are you thinking of @ 200mm??

At least the main white LED light at 460nm is being cut out. Something of which the former LPS-D1 and LPS-P2 did not :- Anyhow, if I get some clear skies, will do a comparison with the my former LPS-D1 and the new LPS-D2, and against the LPS-V4 too.

If their graphs are to be believed, this is what they've put on their page :-

Just FYI, IDAS has just released a new light pollution suppressor, LPS-D2. This suppresses LED wavelengths along with high pressure sodium. I've just picked this up 3-4 hrs ago and have not had a chance to try it out yet :- v

Gotcha. Anyhow if you decide to look back into the T-Factory product again, there's been a few changes/options available now that makes it a little more versatile to take drink bottles as counterweights which makes it great for travel. However I think I could do with a shorter counterweight shaft and an additional counterweight as the longer counterweight shaft is more susceptible to vibrations.

Mikey, Sorry for the late response...too late for your canaries trip. Did you try reaching out to T-Factory directly to see if you could pick up their updated PCB-EQ3?