Xiga

@teoria_del_big_bang thanks for posting your picture above. It made me go and have a look in my box, and sure enough, mine also has the same grub screws 😃

Qhy clearly think it should be possible to adjust the central screws with a Phillips head screwdriver. I'm not using a filter wheel, just a simple filter drawer, and it looks like I can access the existing screws, even without breaking down the optical train. I'll obviously be removing it anyway, to make the adjustments, so Adam @tooth_dr is there any real need to replace the screws with Allen key ones?

Thanks Adam! 👍

I get it now.  For some reason, I thought the holes in the faceplate were also threaded, but I see now that when you loosen the central bolt the faceplate is now free to move out, hence the need for the grub screws. Out of interest,  how many of the 3 sets did you need to adjust on yours? 

Think I'll also get some black PTFE tape to cover up any small gaps that appear post-adjustment, just to keep any moisture or dust at bay. 

I've just discovered this neat method of testing/correcting for tilt. Very impressed with what you have done there Adam @tooth_dr ! 

I think i also have some tilt on my 268m. At just ~F6.3 it's not as big of a deal, but it's still noticeable. Adam, do you have a link for where you got your screws from? I'm going to have a go at this myself. 

On your method of adjusting the tilt, did you leave the small grub screws loose, and only lightly tighten them up when you were done? In fact, what do the grub screws actually do, seeing as there are no holes for them to screw into on the camera itself? I take it the central hex bolt is the one used for actually doing the adjustments, and are the grub screws only there to stop the possibility of the lightly-raised faceplate from ever falling back down again? 

Love the Double Cluster. Some absolute corkers on show here. 

This was my own humble effort from around this time last year. 100 mins of colour from a Nikon D5300 and 100 mins of Lum from an Atik 383l+

Still getting my eye back in after a year out. Had another look at this tonight, and decided the previous version was just too bright. Plus, it was bringing out the noise a bit too much for my liking, so used Curves to lower the midtones a bit. Also, reduced the image size down to 70%. Calling it quits on this one now! 

Hi guys

Just came across this tonight. It's similar to Starnet++, in that it uses AI to remove stars, but it's all done within PS and apparently it leaves far fewer artefacts behind. 

https://www.rc-astro.com/resources/StarXTerminator/

Personally, i find $60 to be a bit steep for what basically amounts to just a single action (especially when you can get a whole suite of actions for a fraction of that price) but it certainly seems to be very effective. It's also very early days in the development, and Russell promises that it will only get better as he continually improves it.

Here is a video of someone doing some early tests of it. 

13 minutes ago, carastro said:

Thanks everyone. 

Thanks Xiga, means a lot.

Not heard of this, and I use PS all the time, but maybe it's in the later versions of PS,  I use CS3.  

Carole 

It's a slider in Camera Raw under the Filters menu. I'm on PS CC 2014 so it's possible it's not on the earlier versions. 

That's wonderful Carole, really nicely processed. Amazing what a difference even a Bortle 4 sky can make. The Samyang 135 F2 is a great lens, and one I'd like to get myself at some point in the future.

Ps - one small piece of feedback, if I may. The image could benefit from a bit more contrast. A quick blast of Dehaze in PS might do the trick, or even just a small curves adjustment, but either way it's still amazing. 

18 minutes ago, Allinthehead said:

That's a great first light, beautifully processed as always.

Thanks Richard! I've had the camera since February, and have been itching to put it to use ever since. 

The camera has definitely impressed me I must say. The sensitivity is great, before with the Atik 383 I could never sufficiently swamp the RN in a Narrowband sub, no matter how long I exposed. No problem in that department now. Only downside is I am currently manually swapping filters. Ok for NB, but for broadband I could quickly end up as a zombie. Maybe next year I can pick up an OSC version of this chip, and leave the mono just for NB. 

49 minutes ago, tooth_dr said:

Very nice Ciarán. I’m sure it feels great to back into it again!   The tilt looks to quite minor, but maybe you have done some corrective work on the stars in that corner?  

Thanks Adam 👍 Hope you're keeping well. 

It does feel good to finally be back imaging again! Although it's been a very frustrating month, as out of about 6 sessions only the last one went without issue. Up to now I've just been lucky to have never had any technical issues with the gear, so this is an unwelcome first for me. I'm hopeful the next clear night will go as planned though, now I've re-jigged the finder-guider. 

The image above has had no star reduction or manipulation. This is just the Ha stars as they are, and I have to say it's so nice not having to tame them in processing, so I'm very pleased with the 3.5nm filter (even though Sadr did have a pretty big halo). Some of the sessions were ok, and one or two showed what I thought looked like tilt, but stacking them all has kind of hidden most of the effect. I also definitely had diff flexure too so that was also muddying the waters. I really need a good session of guiding on both sides of the meridian to know for sure where things are at. 

After what has seemed like an interminable wait, i've finally been able to complete an image again, almost a full year since my last one. I sent the mount off to get 'tuned' but the less said about that the better. Anyways, it's good to be back in the saddle again. 

Acquisition for this one has been difficult. After 5 years of doing AP, and not losing a single sub, not one (even doing 20 min ones regularly) i'm now having issues with eggy stars (at best) or trailed ones (at worst). I've been blaming the mount during the last month or so that it took to capture this data, but in truth i think it's mostly been down to differential flexure, a problem i never had before. Anyway, i've now got some new rings and mounting arrangement for the finder-guider, and was able to use it on the last data session, and things went a lot better for it, so fingers crossed i'm over the worst of it now. Still need one more good night on both sides of the meridian to know for sure though. 

So even after ditching a lot of subs, i was still able to salvage most of the Oiii and Sii data for this, as even though the stars were not great, i was only using those channels for tone mapping anyway (and a separate HSO stack just for star colours too). Thankfully, most of the Ha data had ok stars, although i do have some tilt towards the bottom left i think, and which i'm trying very hard to ignore!

Details:

53 x 6 mins of Ha (Baader 3.5nm UNB)
42 x 6 mins of Oiii (Baader 8.5nm)
23 x 6 mins of Sii (Baader 8nm)

Total exposure 11:48

SW80ED, HEQ5-Pro.

Qhy268m. Mode 1, Gain 56, Offset 25, -10c. 

Stacked in AstroPixelProcessor, processed in PS. Resized to 80% as i didn't think 100% was offering anything more, and it also helped hide a little more noise. 

C&C welcome, and CS!

Wow, that is seriously good Ivo. Easily the best rendition of this i've come across. 

Good skills! 👌

On 12/09/2021 at 16:01, ollypenrice said:

I don't think we can assume that binning will 'just work.'  I've had two CCD cameras on which it produced too many artifacts to be of any use at all and others on which it worked perfectly. This includes two cameras of the same make and model. I'm also finding with a CMOS camera (ASI 2600) that software binning in AstroArt is giving me poor stars on which the colours are not properly mixed. I get different coloured stellar edges from one side to the other. Perhaps other software will work better but I mention it as a 'problem in progress' which we're still exploring.

Olly

@ollypenrice how are you stacking your ASI 2600 subs? Are you using Bayer Drizzle? When you have well-dithered subs, and lots of them (which is pretty much always the case with OSC CMOS) then Bayer Drizzle basically bypasses the need to do interpolation. You might find that fine-scale colour details are a bit more accurate, and it could make a difference when then binning. Worth a shot i would think. Unless you are already using Bayer Drizzle, in which case ignore me! 😄

Congratulations to Bryan and Matt, top work guys! 

And thanks again to IKI and FLO for another great data set and challenge. 

Bit late to the party with this one. Didn't have as much time on it as i would have liked, but i found it pretty difficult to process i must admit. 

APP used for Gradient Reduction, Siril used for Photometric Colour Calibration, then into PS for everything else. Colour stretched manually in PS using Arcsinh, and the RGB was used for the galaxy cores. 

Didn't use starnet for a change. instead i just went with old-school star reduction. 

39 minutes ago, Rustang said:

Cheers, shame its really noisy but it was only a quick test anyway.

Kit is SW80 ED DS Pro and SW HEQ5 Pro Mount.

Nice one Russ.

We have very similar kit. Mount, scope and filter. Only my camera (Qhy268m) is different to yours. I shot Sadr a couple of weeks back and saw halos with my Ha filter, so will be interested to see how you get on. 

Also really sorry to hear this. Hope you get a resolution soon.

I've been down this road recently myself. I won't go into details, for the sake of my own sanity. I'll let you draw your own conclusions from that. 

Finally got a chance a couple of nights ago to have a very brief first light with my Qhy268m and the Baader 2" 3.5nm CMOS Ha filter (not the super fast F2 ones). 

Zero processing on this, just a stretch, not even cropped. It's just 9 x 360s so only 54 mins. I need proper calibration frames too, this has only had a very quick BPM and a single 500s dark (not even the same length lol) applied, together with some similarly badly calibrated flats! Time to finally get some decent calibration frames now i'm finally back in the game after a long 10 months out. 

I'm happy with the overall contrast and star sizes, but am a bit disappointed in the Sadr halo if i'm being honest. I wouldn't have been surprised to see halos in Oiii or Sii, but i was expecting the Ha to be virtually halo-free. In all my time using the 7nm Ha i never really saw any halos at all, i was really happy with it. I know Sadr is about as bad a case as it gets (annoyingly i never shot this with my 7nm) but what do you guys think, does it look ok or not? 

I also might have a slight spacing issue. Not completely sure, perhaps a tiny bit more spacing needed. Hard to say for sure, as immediately after the meridian flip i got 2 more subs before the clouds came in, but both had really eggy stars! I had moved my finder-guider to a dovetail on top of the SW 80ed (supposedly for better balance), but i think that may have introduced some diff flex, so i've moved it back again. Just need another test session on either side of the meridian to know for sure if it's ok now, then i'll move on to trying to get any tilt or spacing issues sorted for good. 

@tooth_dr as you know i have the same camera and i'm also in the process of trying to get my stars right as well. Hoping to get my differential flexure problems sorted for good on the next clear night, then i'll be ditching the Baader Clicklock and moving to an all threaded connection to hopefully eliminate any tilt issues. FWIW,I also put some of my test session Ha subs through ASTAP (as a cheap alternative to CCDI) and it told me i had a bit of tilt, usually less than 10% but i found the variability between subs to be huge, even with subsequent subs, which makes no sense to me. One would be ok, and then suddenly the next would indicate quite a lot of tilt, so i don't plan on using ASTAP to determine my tilt issues now. I'm just going to go by eye and draw a line under it when i find i hit a point where it doesn't overly bother me anymore lol. 

On your setup though, i had an idea. For the 3 sets of data you captured above, do any of them include subs from pre and post meridian flip? If any do, then you could take the subs from immediately before and after the flip, register them with each other and then compare. If it is tilt due to the focuser in any way, then the tilt should move to the opposite side and you should clearly see a big difference in star shapes in each corner. Conversely, if there is no major change, then it is probably more like a backfocus, focus, or collimation issue. Something to try out at least. 

David, if you already own a tablet you could give that a try. I still use an old iPad for doing my flats and it works great. Back when I used my modified DSLR with an IDAS-D1 filter, my flats were also unbalanced. I'm not sure it was even an issue for my setup, but for peace of mind I found an easy solution, which was to use a simple full screen colour app which had 3 sliders for RGB (0 to 255) which allowed me to set the colour so my flats would have a balanced histogram in all 3 channels. Could be worth a try, especially if you already have a tablet lying around somewhere, and would save you some £££'s. 

On 23/07/2021 at 18:20, LeftyAstro said:

@tooth_dr

@tooth_dr Right across the middle of my O III (and in some other places hard to see). I haven't been able to try these out because of clouds, so I have no idea of the impact. What were you able to notice in your tests? I guess if I'm paying 1k+ for a filterset, I would like them to not have these scratches, but if it doesn't result in reflections or something egregious (Idk, loss of transmission? If that's how it works) then it's not something I would pursue further

I have to agree, that looks way beyond acceptable to me. I'd be sending that back without doubt. Also disappointing to see the halos in the Oiii and Sii subs above. I was really hoping Baader would have fixed these but it appears not. My old Baader Sii gives pretty bad halos.

I ordered one of the 3.5nm Ha CMOS ones myself (not the super fast one though) and it arrived during the week. No scratchets or marks on it that I can see at least. I did notice that colour wise it looked clear, compared to the orange and green sides of the old filter which I thought was interesting. Hope to get a chance to use it soon. 

This is going to be fascinating to watch@ollypenrice! Can't wait to see your results with this once you've ironed out all the kinks.

ps - TAIC recently did a presentation on the RASA, specifically the 8" version. Could be worth a skim in case it contains a few nuggets of information. 

I've also ordered one of these 2" CMOS 3.5nm filters, but just the Ha one. Looking forward to using it but am pretty relaxed about delivery time, as we've no astro dark up here in N.I for another month or so anyway. 

Ps - I was watching one of The Astro Imaging Channel's YouTube videos recently, the one on the RASA 8, and the presenter said that Fast filters (I.e ones that work down to F2) are only needed if you are using filters of around 3nm. He said even 5nm filters work just fine on fast optics. Just thought I'd pass it on in case it proves useful to some (assuming it's true of course!). 

Thanks all ☺️

On 30/06/2021 at 18:56, Allinthehead said:

My image below made the shortlist😀

 

Congratulations Richard! A real badge of honour even to just make the shortlist. Well done! 👏