powerlord

SCNR it and see where that gets you. I don't know pixinsight, but when you say you linear fitted them, not sure what that means but as Vlaiv suggests - open all 3 masters next to each other, and aim to make the histograms peak around the same amount. usually this will mean stretching the Sii and Oiii up to where the Ha is. then combine them. Also, you may want to try the script thing that does this someone mentioned - (google search later) - SHO-AIP.

should do - if they are M51 aka 50.6mm or so. I filed/grinded a wee bit off the outside of the adapter, then the trickiest bit is hammering the first bit in straight. once you've got it in a bit all the way around, a block of wood on top and a rubber mallet - and tapping, checking if level and if not, next tap on that bit, etc - and slowly stretches the ali tube out a tiny bit to fit. Reason for this is that I thought for a while the reason I was getting rubbish dark stars with my Svbony 50mm was the colour asi120 I was using, but last night I was using identical 120mm mini cameras pointed at the same place - the one with a SW 50mm guider (this one I'd knocked up a 3d printed adapter for) had lovely sharp bright stars - and the svbony, same camera settings had rubbish washed out stars I could hardly see. Maybe I've just got a rubbish svbony scope, but anyway - had another SW50mm sititng in a box unused so figured it makes sense to use what I know works. stu

For info - didn't fancy paying 29 quid + postage for the astro essentials m51 adapter to use my sw finder as a guide scope. Cheap unthreaded 2" to 1.25" adapter, rubber mallet and voila - works a treat. Shown with a similar though not identical adapter below to one battered in. Has added advantage of easier quick focus.

i set it up once a while back. tbh it didn't really add any value to me. I prefer to just have it plugged in with usb for my flashforge and wifi direct to mac for the anycubic - no need for sdcards. you can see the print progress/percentage on simple3d/cura and its quick to cancel, restart, etc with no faffing around with another UI, etc. I suppose the main benefit for some is to not have the computer on and/or if your printer is not in the same room as your computer ? My prints rarely take longer than a few hours, and it's usually an iterative process (that one is just about right, make a few changes, print again, etc) - octoprint added nothing for me other than faff. But I certainly know others who swear by it - I don't think it needs a pi4 though does it ? then again last time I used it the pi4 didn't exist. Why still use the sdcard ? is it again - to turn pc off ? stu

yeh a cheap dremel is great for finishing off prints - the sand wheels work a treat - just go over the thing and smooth in no time

deleting

yeh imho films look rubbish with a calibrated monitor. But you can have multiple profiles easily enough and swap between them. Or you might find you like it fine. It's a pity somone like FLO don't offer a library to borrow a calibration device cheaply - they are not inexpensive devices and once you've used it. it just sits on a shelf. stu

yeh, it is available, (e.g. easly on macos), but doesn't mean folk do it. A high proportion of viewers of forums such as this will be on mobile or tablet devices that have no easy way to calibrate and very definately are NOT calibrated in such a way that uncompressed blacks show. I'm pretty confident that there is general sort of profile there. this article sums it up well https://blogs.scientificamerican.com/symbiartic/how-to-calibrate-your-monitor/ Unless I've chosen the wrong standard to calibrate too (very possible) I've ended up with a gamma more like 1.8 - that washed out look that it correct says allows you to see all sahdes of black. And as it also says, most users are on a gamma of 2.2 - which compresses blacks more. to quote: " If you create mostly images that will be viewed on screen – for the web, PowerPoint, video games, etc. – set your gamma to 2.2. This will help ensure that your images look consistent across the widest range of computers used in business and the mass consumer market. On the other hand, if you still create most of your work for print (as I do), stick with 1.8. Not only is this setting more compatible with high-end printing system, it also produces noticeably lighter images on screen. This helps you see detail in shadows, something that is critical when creating and editing digital images." I believe I have calibrated very much to the later. I'll run up DisplayCAL again - maybe I've just been calibrating to the wrong standard ?

yup it is. true. no argument there. as Dave just proved - that works well - me, you dave - all see the same thing. However it doesn't help those who have a more 'regular' monitor. unless we calibrate to that 'standard' - but of course there is none other than my general experience that indicate lots of folk don't. I suppose just like music, that's their fault. But call me a popularist, but I'd like to be able to post my pics to look the way i want them to for those too. I think I might try starting to post 2 versions - one for calibrate viewing (the correct one if you like), and one compressed to look good on mobile devices and more regular pcs.. see how that goes down. I find I already to that for sending pics to family on whatsapp, etc as mobile devices nearly aways have this compressed profile. I would say, that for those with calibrated monitors who comment/critique a user's photos - it may be worth bearing in mind that the creator may not have a calibrated monitor. You may suggest they have over stretched an image for example, but you are not considering that to them, they see a perfectly stretched one. And of course vice versa. Short of mandating we all have the same standard calibrated monitors, it is always going to be a factor when considering dark sections I think. Colour - less so - as I think most modern monitors respond reasonably unless the user has made the profile massively warm or cool ? I think it might explain why sometimes I've seen someone comment on a photo (not necessarily mine) with a stretching comment (too much, not enough), and I've thought -huh.. looks ok to me. Just one of those things I suppose. stu

Now, you see I don't think it's as simple as that. Your analogy is valid, but a bad one imho. A better one is my monitor speakers. They are great for editing and mixing music as they have a flat frequency response, and so I can make a mix which I know will sound similar on other music creators monitor speakers. However, the vast majority of music listens do not list on monitor speakers - so we edit music to be more flat on there (to sound bright/lacking bass) - you would NOT want to listen to music on monitor speakers. However the music will then tend to sound good on a regular joe blogs speaker setup. I believe the same is the case here - I should probably edit my pictures not to look good on my monitor (similarly to how I edit music to not sound good on my monitor speakers - but be flat) so that it will be good on regular speakers. Editing on a calibrated monitor is slightly analogous to editing video in a Log format ? stu

Well, you will do. that's my point. Sorry if I'm not being clear. IF you have a calibrated monitor, 1 will look great - all shells clear. IF you don't, and your monitor is more 'typically' setup - it will crush blacks - that's the usual sort of profile. And you'll find it difficult to see the outer shells.

If you can see the fainter bits, then yeh the 3rd will look too stretched. But for those who can't, the 3rd will look 'normal'. I suppose that's what I'm getting at. Oh no doubt it's over sampled - it's asi2600 shot with a 300p (0.5x0.5")! But none of that changes the gamut issue tbh. The fact remains I'd be interested in how many people can clearly see the outer clouds in the first image. My feeling is there is maybe, as you say a bit of compromise necessary for those of us using calibrated monitors if we want all the darker bits - whether its dark nebula or dust, etc be visible to most viewers ? While keeping our own 'fully gamut' version for ourselves or printing, etc ?

Hi chaps, A while ago I catibrated all my monitors with my Spyder 5 (https://spyderx.datacolor.com/) A bit like monitor speakers (which I use for recording music), this is maybe not how you would want to actually use a monitor like all the time - since it's purpose is really to standardise colours, and aid professional print, video and photography. It creates a very deep profile where the smallest change from absolute black is determinable, etc. After hearing others on the forum, this seemed like a good idea as a basis for editing my Astro pics. However I'm now, not so sure. Here's an example - and a bit like trying to demo different sound quality and youtube, there will have to be some compromises to try to demo colour profiles on here so it's viewable on everybody's monitor (and really that's the crux of the matter). Here's M27 - 30 mins of data shot last night. The first picture is as edited by me on my calibrated monitor. On that calibrated monitor I see lots of Oiii clouds out to the sides of the dumbbell. However, if you are viewing this on a non-calibrated monitor, as most of you will be (stuff generally just looks better with deeper backs, more compression), you probably don't see them. To try to demonstrate what you see on a calibrated monitor, I took a pic on my phone of the screen - this kinda worked. ignore the blown out highlights - which are not blown out on the monitor, and note the shadow portions - this is what I see - all that oiii cloud billowing out: \ So my question is really, IF the audience of a photo is to be on the internet, on a forum such as this, it seems to me posting 'properly' calibrated and edited photos is maybe not correct ? Would I be better creating and edited version which I create while setting my monitor to a more regular 'out the box reduced colour gamut' that is more representative of what most people have ? If I do that, I get something like this (this was done quickly and could be better - but basically I've applied a curve to the lower end shadows, pulling them up into visibility on such a profile: Obviously doing so, necessarily compresses the colour gamut - so there's less depth in the core - but if you are viewing this on your phone/tablet or a 'regular' monitor you CAN now probably see those outer Oiii clouds. Opinions ? stu

and a test of the original file, with the profile only changed to be my mac profile.

here's a stretch that looks ok when I change my monitor profile to be a regular one

hmm I'm noticing that the outer rings are far less obvious on my cheaper work monitor here, than on my imac 5k extended gamut. Maybe I need to pull the data up a bit so it is more visible on regular monitors/screens. This is a pic of what I see on my screen (if this works)

asiair restarts. i get a 'reconnecting' on my tablet, then I hear the asiair beep. Yeh, that was my only idea - but the only things I have powered by asiair is a fan (0.1a), and the camera. So even it was drawing 3a max it should still be fine. Nothing has changed usb ports wise - well unless the asi2600 is taking too much power there, but you were seeing disconnects not restarts there in that case, so doubt it's that. But so far, a few hours in to shooting darks, moving the camera to direct power, and the mount instead to the asiair power seems to have sorted restarts. Maybe there is some sort of spike the asi2600 needs that the asiair can't provide or something. frankly - IF it has fixed it, it's no skin of my nose where it gets it's power.. so fingers crossed.

Well, didn't start well last night. Got asi2600mc from FLO, and decided to setup the SW 300p monster. After straightforward PA, it decided to play funny with gotos - going totally wrong way. Took numerous restarts of mount to sort out. Then I started to have issued with my asiair - it kept randomly restarting itself. The only change to the setup is the new camera. weird. It kept doing this all night, so I'd setup an autorun, and then find hours later it had restarted and nothing imaged. In the end I managed to get 10x180 second images of M27. So 30 mins. I didn't expect much to be honest, but I'm pretty amazed to see it has started to bring out the outer Oiii clouds. This was all with 2" L-extreme filter. I've swapped the camera power now to not go through asiair, but direct to my power distro box and kicked off a session of dark frames to see if it's any more stable. If it's sorted the restart issue, I hope to get some more data over the next few sessions. I know it's crazy overkill - asi2600 + 300p (0.5"x0.5" per pixel). My guiding was good (around 0.3-0.5") but seeing isn't gonna be that good. However, I like the results and reckon I'll leave this setup for a few sessions and try more M27 and other targets. I did hope to get an hour in on M16, but by the time I'd sorted all the above out, it had disappeared behind my neighbour's tree.

Getting ready for first light with my new asi2600mc.. What's that you say? Pixel size, 300p 1500mm FL gives 0.5" per pixel.. madness? Pfft bring it on.. Laws of physics are just suggestions imho. 😛 p.s. 300PDS makes the asi2600mc look tiny.

I've been a naughty boy. Flo customer return. 500 quid off.. Couldn't let that pass by. 😬

I did some side by sides - 1600 vs 533 of M16 and there was lots more detail in the 1600 Ha. Now, of course slightly different fov, etc, etc - but does seem to me that 9mp/4 = 2.25mp is gonna be less sharp that 12mp surely ? At least that's what I found.

I still love my 6d, but I don't use it anything like as much as my 533mc tbh. As a first astro cam, a 2nd hand 533 is hard to beat. Coincidentally, cough, my 533 will be up for sale soon since I've just bought a 2600 ! However, I doubt you'll get one for 500 quid - they are £950 new, and sell used for around 700 I think ? I got my 6d for 350 as it had a cracked screen cover (replaced easily for a fiver). Then had it modified to remove the LPF2. You can get great results with it - but do bare in mind you'll need something like a 2" L-extreme for NB, and that your OTA will have to be capable of feeding a FF sensor. Saying that - I love the widefield you can get with the FF sensor and something like the SY135 lens - I especially like mono Ha from it (i.e. shooting with the L-extreme and just keeping the red channel).

damn you Olly - you got me thinking about 2600s again... I do like using my 533 OSC, but I hate the limited resolution compared to my 1600 (i.e. once you include bayer matrix is much lower). So.. of course I popped over to FLO just to see how much they cost these days - and they have a customer return with 500 quid off, full warranty. Well.. they don't anymore. 😁

Yup, again though it's important to remember the application - a home pier, not an oil rig. So yeh, it's just grinding off the area to weld which I'd be doing anyway. A coat of zinc paint base coat, then paint on top is all you'd need imho. More coats if its intended use was outside in the elements was the plan. Im going to have a go in solidworks simulation and see if I can model a few different designs. I do think it's important to remember that it's just trying to be rigid enough for normal use with 30kg or so of kit on there - a requirement that my existing 2" SS skywatcher tripod manages fine. As Persig said in Art of Motorcycle Maintainance, quality is not an absolute. A design fails if it has more of it that is needed. Imho most steel pier designs ignore that and build something with far far higher rigidity that is practically necessary, making them very poor designs. Or to put it another way - "A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away" Antoine de Saint-Exupery

I don't really want ali : 1. it's nothing like as strong for a given size 2. it's a pain to weld (though I can weld it)