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agthomson

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About agthomson

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    Star Forming

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    Bankfoot, Perthshire, Scotland
  1. So, after many frustrating nights, all caused by me inadvertedly chaning a setting or two in SharpCap, I finally have something that's actually usable from a session with my Dual Narrowband L-eNhance filter. This was 22 x 4 min exposures taken on a WO ZS61 with an L-eNhance dual narrowband filter using an ASI294MC Pro at 200 gain. Mount is an HEQ5, guided in PHD2. Images were stacked in DSS using recommended settings, apart from the 10 Dark frames that were shot and stacked in SharpCap, with the stacked Dark image added to DSS as a master Dark. This did a great job of removing the amp glow. Only processing was individual channel levels to balance/align them, a quick stretch and a minor adjustment to curves. Self-critique: I messed up the framing a bit, so lost IC 1795 from the bottom (or top?) of the heart. I'm also terrible at processing in Photoshop, so there are colour balance sisues. I'm still working out the best way to process images taken with this filter! Focus looks okay to me, but maybe a little soft? Next steps? I want to up the exposure time a bit to maybe 5 or 6 minutes while still leaving the gain at 200. I'll then reduce the gain from there if necessary, but this filter seems to need all the time and gain it can get. the 294MC Pro works quite well at high gains anyway. Any pointers? Better processing tips?
  2. Exactly. I need to work out what the cause is. On the plus side I now have a 64-bit version of Ubuntu Mate running everything I need that I can VNC into via its hotspot.
  3. I had a huge issue with StellarMate OS on the Pi4. It's fine during the initial setup after flashing, but after I close down the Pi the StellarMate will never fully reboot. I can connect to the hotspot, but not sign in or do anything. In the end I installed Ubuntu Mate on the Pi4, then INDILib, KSTARS, PHD2, then a VNC client. I then had the issue that the Pi4 wouldn't boot to a desktop without a monitor, so had to install a dummy display driver. Now all set up, but not tested yet. I'll take another look at StellarMate with a screen connected to see exactly what's happening. I have seen a few people post about just getting a blank screen after shutting down and rebooting, but others saying it all works fine, so not sure what the root cause is.
  4. Hi all, hoping for some words of wisdom! I recently purchased an Optolong L-enHance filter to go with my ASI294MC Pro and ZS61, partly to remove light pollution and partly to allow me to experiment with targets I just couldn't get data on before. My understanding of this filter, as shown here, is that it lets through Ha, Hb and OIII as Red Blue and Green respectively. The filter adds a green hue to images, as shown here (from Astrobackyard), which I should be able to sort out via flats etc. For my first test session with the filter I pointed the scope at the Heart nebula, didn't capture flats, and for whatever reason DSS won't stack my darks, possibly as I captured in 8-bit PNG by accident. Ignoring the issues with the data, i'd like to do something with it if I can. Below are my stacked red, green and blue channels. Unstretched. Blue is as I expected - quite empty. Red contains the most prominent parts of the Heart Nebula, but green contains more than I expected. How would you combine these layers back into a colour image, ignoring fine tuning for now? My thinking is: Red should be Red + Green, taking the brightest pixel from each to form a new red (or something close to that) Green should be a mix of Red and Blue so that stars have a more natural colour, and the brighter bits of nebula trend towards lighter red Blue should stay blue, but possibly take in some of Red (brightest 5% or something? Does this make any sense? Any help / suggestions would be much appreciated!
  5. Olly, thanks for that. Checked the polarscope in daylight and all is fine, so just working off the assumption that the scale is inaccurate and there's nothing to worry about. Regarding your second point, that was my feeling when capturing images - they seemed fine and would likely stack quite well (albeit a little green due to the filter). When stacked, the solid colour in the middle of the nebula and the bottom right of the heart are essentially a solid colour with no distinguishable detail. This might be a stacking issue, and something I need to play around with. I haven't been able to stack in the darks I collected at the same time as these have totally thrown off the image calibration (made it very noisy and neon green), but will take another look this evening. Maybe DSS is the area I need to focus on. There may also be an issue with the debayering that I need to look at which will be hard given I only have debayered PNG files. Serves me righ tfor trying to cut a few corners.
  6. Okay, this is a multi-part question, but instead of creating a few threads i'll bundle them all here as they are all related to AP. The scale on the side of my HEQ5 seems off. Is that common? I'm at ~56.5N, but to get polaris in the polarscope, or evn when using SharpCap, I need to crank it up to 59. Not a huge issue, but beginning to question things! I re-set my HEQ5 to what it should be for last night's session, which is the 1st of the season (and only my 5th with the HEQ5) and just assumed SharpCap was telling lies before. I'm polar aligning, then fine-tuning in SharpCap (also normally used for capture), using PHD for guiding and ASCOM/StellariumScope for GoTo and 3SA. I made the mistake of updating software a few weeks ago in preparation for darker skies and the connections were very unstable to say the least. Couldn;t 3SA properly, telescope wouldn't slew to a target and the telescope and Stellarium weren't sync'd. Having 3 or 4 pieces of software open didn't help - can I simplify this? I'm really considering ASIAIR as I only own ZWO cameras and a compatible mount. Looked at SGP and APT before but it seemed they also needed 3rd party software, or did I miss something? I made several mistakes last night in a rush as it took close to two hours to work all of the bugs out. I have lost a bit of faith in SharpCap for image gathering (plus it can't dither properly) so gave ASICAP a chance (mistake 1). I have an Optoplon L-enHance filter for some Ha targets and to deal with LP, so targeted the Heart Nebula. 30s check exposures in SharpCap with 500 gain looked very promising. I forgot to switch on the cooler when I swapped back from SharpCap to ASICAP (mistake 2) but temps seemed stable at 1.5deg in all images. I also imaged at RAW8 (is this a mistake?) and imaged directly to .PNG as opposed to my usual raw (mistake 4). For some unknown reason I settled on 3min subs at unity gain (mistake 5) and the resulting images are unusable pretty much. I have attached a single sub. My 3rd question is does the combination of all of those mistakes explain the image I have, or can I narrow it down? I expected the green hue due to the filter, and was aware of the very bright star to the right of the image. The moon was out but relatively far away. I seem to have blown out the detail of the nebula, lost all the faint detail, and looking at the histogram I have lost a lot of data to the left of the curve. The image is also beyond noisy. Any help would be much appreciated!
  7. So, coming to the end of my imaging season and I have cracked my cheap LP filter (a Baader one) which has left my images washed out for the last two sessions. I left it in my imaging train and I assume the expansion and contraction with going from inside to outside just stressed the glass in the metal ring and it cracked. I suppose the first question is should I be fully dismantling my setup every time or is it usually safe to leave it all assembled and I've just got unlucky with a cheap filter? The next question is what route do I go down to replace it? I was really considering getting a filter wheel so I could image in HA on my ASI 294MC. Yes, I know it's a OSC camera, but HA is still possible for enhancing things like the Horsehead nebula etc - i'll just have to deal with the lower detail and longer exposures. Would getting a filterwheel and essentially fitting two filters; LP in slot 1 and HA in slot 2 make sense? I saw that the AstroBackyard guy was using a Starzonia filter drawer so he could swap between his LP and HA filter with a similar setup, so was considering a similar system (https://www.365astronomy.com/TS-Optics-Filter-Quick-Changer-incl.-1x-2-Filter-Drawer-Low-Profile.html) but can't see too many benefits over a filterwheel other than using 2" filters. Thoughts?
  8. [UPDATE] Thanks everyone for their input in this, it has been very helpful. I gave it all another go with my current equipment last night, swapping to pulse guiding as opposed to via ST4. I believe my issue with guiding might have been two-fold. Firstly DEC was set to only guide in either North or South (can't remember which), so I just set that to Auto. Swapping to pulse guiding meant a few more settings to play around with as the default values are useless. The guiding rate for whatever reason in EQMOD defaults to 0.1x and I had to quickly google to find more suitable values as calibration wouldn't detect enough movement. The second issue with guiding and star trailing was that EQMOD has "limits" on by default which meant the mount tracked for a while, hit a limit and then wasn't tracking in sidereal any more and guiding went bonkers. Oversight from my part, as i'm sure most of my problems are! Guiding graphs didn't look great, but as i'm still playing around with pulse duration and aggressiveness I was happy enough. These will improve over time as I learn what does and doesn't work for my setup. Being able to get 5 minute subs and no trails with reasonable polar alignment is quite a big step for me, but as always with astrophotography, you solve one problem and several others appear! A quick 90mins of 5 min subs on the Pinwheel galaxy has revealed that I need to start dithering (I assume) to help remove the checkerboard effect on my final stacked and processed image. I've never imaged at that exposure length and low gain before (previous max was about 45-60s at maybe 200 gain). Also, dew! And light pollution. For dithering, SharpCap seems terrible from what I can see / read as it looks like it needs to drop the next frame which would double the length of my imaging session. I'll need to check out SG Pro and APT in more detail to see which one fits my needs (level) the best. While i'm certainly a novice, as I'm not familiar with anything really maybe it's better to jump into SG Pro now as opposed to later? I don't know. Nighttime imaging n' astronomy (NINA) looks interesting but can't really tell if it's fully-featured. I'll ask my other questions in new threads in the appropriate place.
  9. Thanks for the suggestion. I think i'll download the trial of SGPro and give it a chance. I was also seriously considering an ASIAir when I bought the HEQ5 given all my equipment is ZWO or ASCOM compliant, but it lacks a few things I'd like to have. Not sure about the tablet interface as touchscreens are fiddly at best, as I'm finding with my Surface Pro. I will give PA though the handset a chance as well.
  10. PA through the polarscope in the mount. I generally get Polaris in roughly the right place in the reticle and then use SharpCap to fine tune. I find it easier than using the reticle for the final adjustments. I do confirm alignment through the polarscope afterwards. Yep, I have a handset. Would it be more beneficial than Eqmod? Seems more disconnected overall to me. I am dumping ST4 as of now. One less cable on the mount I guess. Didn't even think to check what Dec was set up as, will add it to my list. I'll also have a look for the log file(s) and see if anything makes sense. Cheers!
  11. Hello all! Again I turn to this forum for advice / wisdom. I've been imaging for a couple of years with a Star Adventurer and DSLR, moving on to a dedicated OSC at the end of last year. Being at the limit of the SA's capacity, I read up about the HEQ5 (or similar mounts) and began to learn the software in's and out's. So, I now have an HEQ5, my imaging scope, and a mini-guidescope. Everything is connected to my laptop (mount to hub of camera via EQDIR cable) and I control the telescope via EQMod. Guidecamera is connected via ST4 to the telescope, but I will change that going forward as it's a useless connection it seems. First outdoor clear sky setup was last night. My general set-up was: rough PA using polarscope fine-tune PA using Sharpcap fire up ASCOM Toolkit / EQMod and verify Lat, Long and Altitude settings fire up StellariumScope & Stellarium slew to bright star, move mount using EQMod, sync mount & stellarium (and repeat for another 1 or 2 stars) slew to imaging target fire up PHD2 and calibrate guide start imaging session in Sharpcap First question - as you can see, during imaging I have Sharpcap, ASCOM Toolkit, EQMod, StellariumScope, Stellarium and PHD2 all open. Is there a package I can use to group these together? SGPro seems okay, but i'd need to keep Sharpcap to fine tune PA (although I can close once aligned). Is it worth getting rid of Stellarium and replacing it with CdC to remove one of the applications? I don't mind paying for a "premium" solution to all of this. Second question - I cannot for the life of me get Sharpcap to plate solve, so when my mount and stellarium aren't in sync it can be a huge pain to tell what exactly i'm looking at and how to align the scope in EQMod. Is this common, or have I messed something up? A quick Google suggests it is very fiddly to set up, so might just find a more elegant solution. Third question - with my PA almost perfect I started up PHD2 and it seemed to calibrate very well in 8 steps or something (I think). Started off guiding, and RA graph looks okay-ish. A bit peaky, but okay. I had upped the % applied and pulse length to 5000 for my Star Adventurer and didn't reduce this. Seemed to be okay with these, although I will likely reduce them. DEC graph was a total write-off with the default settings. Immediately went off the scale never to be seen again. Any idea what caused this, and how to avoid this? It caused noticeable trails even at 90s, so had to bin guiding. Scope seemed level from the bubble in the HEQ5 head, but I suppose it could be misleading.
  12. Thanks for the replies everyone. I suppose when the EQM-35 was announced it looked exactly like a SA upgrade / replacement which is what got me thinking, but the longevity of it (or lack of) had me considering the HEQ5. By all accounts they share a tripod, but the HEQ5 has better resolution albeit with less teeth on the RA gear. I take the points about portability, and maybe read too much into the modular nature of the EQM-35. Okay, so shopping list stands at HEQ5 Pro (belt modded), EQDIR USB Cable, Extension Tube (need the extra clearance sometimes) and power supply. Missing anything?
  13. Before I start, I know these two mounts aren't directly comparable, so please consider my current set-up and requirements if you could! I think I wlready know the answer to my own question, but I suppose i'm just looking for confirmation that i'm not ignoring something. Right now I am more than happy with the way my set-up functions, other than having to manually find fainter objects in the sky (nightmare if there's few stars to hop between). I love the ZS61 and the Star Adventurer combo for the easier targets such as Andromeda, Pliades, and Orion even if at 2.5kg I am at the limit of the mounts capability (possibly beyond?). The EQM-35 caught my eye as it's only £555 and is relatively portable, meaning I could sell my Star adventurer to help finance the EQM-35. The payload capacity, at 7kg is enough for me just now, even if I do decide to add a ED80 or something to my setup. By the time i've sold the SA, and added a powerbank and cables etc I would probbaly have spent a total of £550-600. The other option is the HEQ5 Pro. Much bigger payload capacity, meaning I could get a bigger scope for DSO's or mount my 200p for visual. It would probably mean I need to keep the SA for trips away, so i'd probably have to spend close to £1k (mount, powerbank, cables) and end up with 2 mounts (the wife would definitely notice 2 of them - I might be able to convince her that the EQM-35 = the SA but in a nicer colour?). Do I just suck it up and get the HEQ5 Pro, or is the EQM-35 a happy medium that would keep me going for a while, and solve my object-finding issue?
  14. https://www.365astronomy.com/Blitz-Hotshoe-dSLR-Camera-Adapter-and-Red-Dot-Finder-COMBO.html When I used my A6000 this is what I used. Works well. Need to get a bracket so I can attach it to my current setup.
  15. Evening all! I too tried guiding, and just got a bunch of errors after selecting a guide star and letting it go, so gave up and turned it off. Will work on it next clear night. Anyway, finally got a first light with the ASI294MC Pro. No flats, darks or bias (need to work out what is and isn't needed for that camera). Stacked in SharpCap (live stacked), and minimal processing in Photoshop (levels, black point, curves, exposure). M31 Andromeda - cooled to -5 degrees, Gain 120, exposure 60s x 45 M45 Pliades - Not cooled, taken at 3 degrees (forgot to switch on cooling), Gain 270, exposure 20s x 116 My spacing was off. I forgot to account for my LP filter properly, so i'm out by at least 5mm which has caused the elongated stars from all edges. The M31 has red artefacts, but I think that's a problem with my combining of the RGB layers in photoshop. In the M45, there's halos around the brighter of the 7 sisters, so need to work on that. I'm also missing a chunk of nebulosity. Not too bad given the moon was out and about. Not a bad 1st light by all accounts!
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