powerlord

Oh I know what works before, I just want a project to play with welder, and with 2nd hand scaffolding cheap, it seemed a good opportunity. large diameter pipe is too expensive - steel prices are through the roof. I don't need a pier myself, so no interest in Todmorden style ones to be honest. If you follow Luke on youtube you'll know he went even simpler - breeze blocks. and is happy with it. I've seen folk happy with a single scaffolding tube upright, filled with cement/sand. So 3 feels like it would be solid enough to almost be overkill. I'm not one to copy others (see my observatory) - I'd rather do something individual and innovative. And learn through the process, even if it fails. 😀

thanks Rusted. Understood, but most people require a pier to not take up too much room - which limits the base size. So I suppose the question is, a basic triangular pier (aka pyramid) vs my 'opposite of a Serrurier' ? And you are saying basically that the pyramid is better. Fair enough. I'm not a mechanical engineer (I'm an electronic one). My thought was smaller triangles, and through reduced rigidity in the middle - it's still 3 x 50mm tube welded together at that point, and in my head it felt like in the real world for what we need stability wise, that would be better than the pyramid. But you are saying it isn't correct ? So then, my question is (as you know more than me by miles here|), do you think that simple pyramid - steel based, 3 x 50mm steel poles, angling in to a smaller top plate has a chance of being rigid enough ? stu

A rough mock up. Each tube is in compression even with sideways forces. Welding where they meet you end up with all triangles. I'd have though this would be very strong? Obviously not to scale here or pier would be 3m high, but you get the idea...

I really just did that for viewing on forum. To try and put an edge to it. It's very soft otherwise to be honest. But I might post a version without topaz sharpening so u can see what u think.

Hi chaps. I've been teaching myself to weld for something to do, and it got me thinking about a scaffold tube based pier. Perhaps 3 or 4 scaffold tubes as central pillar. Might need a bit joining them together half way up for rigidity. Old poles are cheap - 3 quid a meter. I was thinking if I got a good solid design I could start making these for people at a reasonable cost rather than the £500+ cost of commercial ones. Stu

yes, but that has to be very close to start with. If you can't even see stars, it won't do anything useful. With the SCT having around 30 full turns, you need to be pretty much spot on before you trigger the asiair AF. In daylight it's really easy. At night it's a pain - usually you can't accurately point at a very bright star - which would give you a massive circle obvious even with out of fov - your on polaris. And unless you are really close you see nothing at all. Video mode would help, if it wasn't for the fact in their wisdom ZWO have a buffer delay on it, so it's just as much of a pain as preview. What I had to do in the end, was plug in a laptop and use firecapture - that gave me a decent refresh rate, and I could work through the whole range to find the focus. It's why I try to record the rough focus point with each config in the form '17 1/2 turn CCW from fully CW' - then I can set up at night. With a new config even if you think back focus is about the same, it can still be off enough that you see nothing and spend ages twiddling one way or the other to see anything. The oberving brigade have it easy with their superior light capture devices. 😛

ta, yeh its only at 24 degrees, and there's lots of light pollution down that low where I am, so not ideal. Even so, the atmosphere was not my friend - star size average of 8 is double what I'd expect with this setup usually. I shot saturn that morning (see planetary) and that also showed the poor seeing. I also thought I'd be smart, having not used this setup before and SCTs having such a massive focal range travel knobs- so I set it all up upstairs in daylight where I could focus on something about a mile away. smuggly then went out at 11 to setup, and realised I'd set it all up with the 6.3FF still on.. so had to start again... farting around trying to see a star for ages, asiair taking a picture and downloading every 10 seconds.. frustrating.

I had scope setup for shooting saturn in the morning. Obviously FF/reducer would usually be used for this - and was for my last attempt, but since it was setup, here's what I managed to get with the asi1600 Ha/Oiii last night. Seeing was not the best, irrespective of what the sites were saying - no doubt because it was boiling hot and the atmosphere wavering around like a swimming pool.

So, I'm definitely a DSO bloke, but here's my go at Saturn - shot with my C9.25 and Baader 2.2x barlow and asi224. I don't think the seeing was great compared to last time I tried this, even though meteoblue said it was - I don't think it takes into account the roasting nights. However, this is the best I could do - this was RGB out with an IR pass svbony filter. IR only filters were much worse, but the IR pass seemed to give more detail. stu

Been 2 months since I posted!! - summer months, etc. Anyhoo - took some ha with the SY135 fully open at F2 with the asi1600 last night. I'd been trying to get the elephant and quid nebula for 4 sessions and still only starting to glimpse the squid - so thought I'd do some Ha with it and then pack that in for a bit, and swap over to the 200mm newt for a bit. So here's the results.

that is an amazing result. WIth the same lens and my asi533 and asi1600 (7nm nb filters) I'm struggling to get clean Ha or Oiii and reckon its band shifting from the fast lens. Too get such a clear squid after 5 hours is remarkable. That IDAS filter seems to be a great match to the SY135 !

I'm trying to get teh squid at the moment. I've done 3 sessions so far, and only now just about making it out. that's with zwo 7nm oiii and astro 6.5nm oiii. Im shooting with a SY135, and even stopped down two, its a quick lens, and I think from my Ha I can see its affecting the amount of Ha I'm getting as I've just elephant trunk in frame too and both should be stronger there than I'm getting. llast week I was up to 15 min subs and still only JUST making it out, bit also masses of oiii noise everywhere making it hard to do anything useful with it. Every time its clear, the ruddy moon is out which isn't helping either. The easiest way to see if you are getting it is to remove the stars from the oiii (green channel if shooting OSC). you should then make it out.

and for those who don't know - all PS plugins work in affinity photo, and this is no exception. You do need to reduce the colour depth to 16 bits per channel as you do for all PS plugins (since PS is only 16 bits per channel), but you can flip it back to 32 afterwards, so your pixels don't go out of bounds while stretching, etc. Doing noiseX and starX in affinity gives you all the benefits of a proper layering/masking system - makes it easy to say, denoise some parts more than others, or pull out stars, denoise, put stars back, etc all with layers so you can easily go back and tweak things. stu (affinity photo luver)

SHO processing with L-extreme: Lot's of ways to do it - it comes down to the G (best to ignore B with L-extreme) being overwelmed by the R signal. George might have did a photometric calibration ? You can do the same in Siril - this will even out the channels, and stop the red overwelming things. To do an SHO, the basic technique is splitting out the channels. easy in Siril or PI or even affinity photo. R is your Ha. G is your Oiii, and B is just a very noisy copy of G so delete it. So G is you B really. So we'll call that B. Then create an articifial 'G' - something like 60% R + 40% G. lets call that G. You can do that with pixmath on Siril or PI. Now you have an Ha (R), fake Sii (G), and Oiii (B) You want to spent a bit of time getting them all to be the same sort of historgram (i.e. same 'hill') so they are each contributing a similar amount of data using levels/curves. And feel free to denoise to at this stage. To SHO, combine then : L = R S = R or G H = R or G O = B The reason I put R or G, is its best to try both S=R, H=G and S=G, H=R to see which you like best. Most of the time I fine S = R, H = G (i.e. wrong way round) gives better results. You might need an SCNR afterwards. Then you can play with curves, etc. You're looking to try and use the pixmathed channel to create a transitional colour. by playing with stuff like affinity photo recolour or PI colour curves you can start to mimik the SHO look and get reds, orange/yellows (golds ) and blues. stu

Just a note to say I now use these much more than I did. Thanks to things like the SCNR, and James' great docs.

4 hours of 10 min subs with my asi533 and L-extreme. OTA - C9.25 with 6.3 FF/Reducer. Processed in Siril and Affinity Photo as usual - though used NoiseXterminator for first time here. No Topaz anywhere. I've always shot this in more widefield before and been unimpressed. I like this crop into it better - more interesting.

So, in topaz that works nice, as you can scroll around you pic seeing the effect, and just clicking on it turns it off for as long as you hold mouse down. So it's really easy to find the right results. Granted, preview takes maybe 3 seconds on my i9 8 core mac, about 1 second on my M1 - maybe it's a lot longer on slower/less core computers. But that sort of idea does work extermely well. The other thing is, if you use it in a real editing package like affinity or PS, you can easily layer and mask multiple versions with different settings for different parts of the image - a bit more around flat areas, a bit less around nebula detail, etc if required (though of course the filters do this anyway), but sometimes if my integration is particularly noisy, its usually in the Oiii and it really is just noise - smoothing that all out can help make something out of very poor data (such as the 20 min M16 I did last week).

sorry Stu 😶

Justr trying it - one thing I don't like.. with starXterminator it's on or off so the fact there is no preview is fine. But with noiseX, it's not.. you are twiddling in the dark so to speak. It'd be great if Russell could make it work with previews. Otherwise it's set settings, apply, close. undo, open, tweak setting, apply, close, undo.. again and again till yer happy. One area where topaz has it much better - I can have 4 different AI models side by side, select my favourite and make a tweak, and see results, and repeat.

Didn't know about that discount. thanks! no brainer now - just bought. 🙂

I want to give it a go. I imagine like StarXterminator (which I have) its another tool in the box - I tend to use starnet2++ by default, but if the results are poor, I try starXterminator and often they are better there (not better all the times of course, or I'd just use that). I'd imagine this might be the same vs topaz (which I also have) - I like the configurability of topaz - I can do as little or as much as I want: it's pretty easy to tune the settings to pull the noise out but not add detail, etc I find but with big large blocks of noise with lots of colour noise topaz struggles to remove it all until you push the colour noise removal up really high, then it starts removing 'good' colour from your nebula/galaxy too. I think it might come down to AI data sets - I am sure topaz has a bunch of astro images in there, but NoiseX is gonna be all astro so will probably be better for a lot of stuff.

So yesterday I shot 50 mins of Ha with the same OTA/FF but with my asi1600. I figured I could get more resolution that way. I then stacked everything fresh but with the Ha and re-edited it all again. I've tried to keep colours more or less the same. There is definately far more detail in the pillars, so I'm please with that experiment I reckon. I'm going to continue to collect integration time now with the asi1600 in Oiii and Sii and remove the asi533 OSC data if the weather is kind!

Here's the raw 2 sub stack if anyone wants to play. stacked in APP eagle-RGB-session_1.fits

haha. 'fraid so. even at 1480mm it's as above. I thought about using without the FF and just doing the pillars at 2350mm , but figured at F10 and with the limited time, it would have been a waste - though seeing was nice last night - some of my stars were FWHM 2ish which isn't usually the case with the SCT. I did consider breaking out the big gun (SW 300PDS) but it's a bit of effort to trek the thing out there and set it up.. and for 20 mins I decided it wasn't worth it for the extra F1.4

Well Ive spent a fair bit with FLO over the last year, but reckon its a bit less than that 😂