AstroGS

5 hours ago, Richard_ said:

Lovely image! I've prefer the Crescent in this type of colour palette, I find the red and blue offer a nice contrast in colour. 

It actually makes me miss the Antlia dual band gold filter - it is probably the best such filter in the market for OSC.

And it also re-iterates the fact that some times even 2-3 hors of data are enough!

On 13/12/2023 at 21:32, Martthebass said:

Really nice image. I also use the SM90EDT but as I’ve the small sensor 533MCPro I shot this using a Redcat51. I’m still struggling to bring out the soap bubble which is just staring to show in the starless image but hoping to get another hour before it dips into the trees this year.

I think a bit of blurx and noisex will make it look very nice!

2 hours ago, Space Oddities said:

Something that comes to mind - although I have no experience in running an observatory - if you use a cloud storage, you would have each file uploaded as it becomes available. Each file should take a few seconds to upload, and the next one would be available a few minutes later, depending on how long your lights are. So you wouldn't monopolise the whole bandwidth for hours.

Besides, I believe most cloud storage apps have a bandwidth limitation setting for upload and download. This could be useful if you're not in a hurry, and want to have the files uploaded in the background, without impacting the bandwidth too much.

You can see the bandwidth using Fast.com or Speedtest.net, and opt for a fraction of the maximum available bandwidth.

Are they charging you with the electricity you use? A more powerful PC would also be consuming more power, so that might be worth considering as well in the equation! 

No they do not charge electricity or any other utilities. These costs are part of the monthly rental fees. 
 

but, I agree that the possibility to store frames online as they become available could be an option. 

14 hours ago, Starflyer said:

Does the AM5 have the ability to search for and set its zero position remotely?  Things can and do go wrong and you need the ability to be able to reset the system into a known state remotely.

Remote hosting is something I'm thinking about too, I hadn't considered only transfering masters, I would expect to have everything uploaded somewhere for me at the end of a session.  It's not like you'll be in a rush for the data, if it takes a few hours then so what, and I reuse my darks and bias for a year and quite often reuse flats for a month or two.

AM5 has the ability either manually or at the end of each session to park the OTA in the home position. The biggest complaint I’m hearing (as I’ve never tried it myself) is that the AM5 is a bit temperamental when it comes to alternative park positions. 
 

Re the file management I’m not sure and I will also need some advice from people with more experience than me. But, taking under consideration that the purpose of such a project, is to get as much data as possible as many night as possible, the total file sizes can escalate pretty fast. I only have a few examples, from my own projects, where  just the 120 light frames from one target resulted quite a few GB of data. 
 

42 minutes ago, Space Oddities said:

Out of curiosity, why do you want to transfer only the master files? Do you have a bandwidth limitation at the remote site?

I was under the impression that most people were using a service like Google Drive or similar, to synchronise the subs in real time to their cloud, and then sync/download everything to their main PC for processing. This way, they don't need a powerful PC at the remote site.

Bandwidth can be an issue as far as I understand - especially when we talk about 100’s of light frames + calibration files. Of course if there is anyone with a personal experience from remote hosting observatories and can advice accordingly. I would love to be able to have a low spec Eagle or mini PC. 

Morning - i am in the process to put together a rig + mount that i will be setting up at a remote telescope hosting facility in Spain. The weather in the UK does not allow me to enjoy this hobby any more (residing in Midlands does not help) and the level of investment so far, in my equipment, cannot be justified with 15 or 20 sessions each year. So, i have reached out to a couple of facilities in Spain that supposedly get over 200 nights of clear skies and with fully automated, secured and insured infrastructure.

I did start planning to build my own backyard obsy, with a roll off roof. I even bought a Pulsar pier, adaptor for my mount and i was about to bite the bullet for a ready-made obsy from shed shed shed. But, i still cannot justify this level of investment for up to 20 sessions a year. 

So, after a lot of thought i will be flying to Spain (subject to space availability on either of the facilities) end of Jan or early Feb, to setup my rig.
 

I will be using my existing available equipment:

• ZWO AM5 on a ZWO pier
• RedCat 61
• ASI2600MM + ZWO Filter Wheel + Antlia 2.8mn filters
• ZWO EAF
• OAG - L + ASI220mm
• Dewheaters + cabling

I am also planning to purchase the following: 

• Deep Sky Dad flat field panel for RC61 - to take calibration frames
• UPS (requested by the remote hosting obsies)
• Ethernet Switch (requested by the remote hosting obsies)
• Wi-Fi Power strips (recommended)

My main concern here is - taking under consideration that i am coming from ASIAir - that i am not sure which route to go down, regarding the PC. I will need to be able to control everything so, i would assume that NINA and PHD2 will be essential but, i would also need the PC to be powerful enough, to manage the pre-processing part and the stacking/ integration on Pixinsight so, i can transfer only the master files. So, i was thinking:

1. Either this one https://www.firstlightoptics.com/offers/offer_beelink-g6r5-5900hx-mini-pc_305574.html that has the ability to support pre- and processing tasks but, it will always be a mini PC
2. or this https://www.widescreen-centre.co.uk/primaluce-lab-eagle5-pro-computer-for-telescopes-and-astrophotography.html

The big difference is the price and i would probably think that the Eagle will be great but, i am not sure if it will cope die to memory and the processor with the integration of multiple files.

So, what are your thoughts? Am i forgetting something? Does anyone has any advice or suggestion for my quest?

nice photo, the colours are really nice and the background very well controlled - very good  and thanks for sharing.

This was a test I did at the end of 2022, where I was playing around a little bit with the Am5, the Stellamira 90ED Triplet, the 2600MC and the Antlia Duo Band filter. Managed to capture 17 frames of 600 sec each + calibration frames.

Back then, I did a quick processing attempt but, I never actually spent enough time as I thought the data was not enough for a better result. But, with the help GradientXpert and the Terminator suite, the result is really nice - at least to my eyes - and I do start to like the wide field view of the crescent nebula.

I hope you enjoy it as well 🙂

So, in order to see how many SGL members would wish to participate, may I suggest that we start sharing ideas on:

1. Possible Targets:

• Cepheus
• Cassiopeia
• Perseus

2. Focal length: 300 - 500 (?)

3. Mono or OSC or combination?

16 hours ago, Elp said:

In terms of organisation it's why chatrooms and platforms like Discord are so popular, real time discussion and all. No reason why it couldn't work here for agreeing projects, could used a shared system similar to SharePoint or a shared GDrive or OneDrive account, it'd need decent data storage but I think if everyone just uploaded their linear calibrated stacks with details in the filename to an agreed standard, it'd be a fairly simple thing to do, someone on here might have their own server which would be easy to FTP (upload files) to.

I would be happy to collate the master files and create one integrated image and then to forward it to whoever does the processing - I wouldn't consider that this is my strongest point. 

On 07/12/2023 at 08:58, ollypenrice said:

Not necessarily. The better the data, the easier the processing. 

Let's assume that, in the first example, you have a number of contributions which fully overlap. That's to say a single image, not a mosaic. These should be linear at this stage. These might be RGB, one shot colour (the same thing), luminance, Ha and OIII. Using Registar, you would put them all into one folder with nothing else in it. One of these frames would be your definitive crop, meaning all the others can cover it fully with, probably, a bit to spare.

1 Open just your definitive crop (AKA Reference Image) in Registar.

2 Choose 'multiple source' and click once on 'Register Images.' The software will open all the images and register each one, resizing and re-aligning where necessary,

3 Go to 'Crop and Pad' and click once so that each image will be cropped to be a perfect fit on your reference image. Save these.

So... in just two clicks you have a full set of linear images which fit each other perfectly, just as if they all came from the same telescope. Absolutely nothing to it.

Next, you'd want to remove gradients on all these images individually. I'd use DBE or ABE in Pixinsight. I'd also run SCNR Green where needed (it usually is) and Blur Xterminator.

Any images with the same filter would then need to be blended together. Eg you have three Ha contributions. I think some software will read them and weight them according to S/N ratio but I don't know about that. I'd probably give the three Ha images a basic stretch, stack them as Photoshop Layers and adjust their opacities till I got the cleanest blend and flatten them. Someone will know a more mathematical way of doing that. It wouldn't be the end of the world if you just gave all three to Registar, weighted them equally and settled for that, assuming they were all worth having.

Now a multi-source mosaic is always going to be more difficult. They are hard enough when everything comes from the same rig. I think APP is the software of choice for mosaics, at the moment. The first and most vital step would be flattening each panel (ABE or DBE/SCNR Green) before asking the software to make the mosaic.

I'd start with a single panel project! If nobody in the group has Registar I'd be happy to do the Register-Crop bit and send them back out. (Possible now we have fibre internet... )

Olly

I do agree that a project like this can be as small or big as we want. I will need to see what will be the best way to organise something like this and then see how many would wish to participate. I ma always open to ideas of course from the more experienced members than me 😉

This is one of the images that inspired me: https://www.astrobin.com/zzoau6/ + the fact that the weather has been atrocious this year and it feels as I never get the opportunity to finish the projects the way I have imagined them. I would genuinely be happy to invest 8-10 hours of data on a target that we would all agree on. The thought to collect 100 hrs of data seems very exciting although, I would agree that processing will be quite the task!

It would be great indeed if the mods could help/ advice how we could evaluate the potential of this project.

Just now, Ouroboros said:

Citizen Imaging!  I like the sound of that. How would it be coordinated? 

Not sure yet - open to suggestions. Initially, I wanted to see if there will be some interest for something like this 🙂

I wanted to share an idea that I have had in my mind for some time now. What if a few of us could come together, agree on a target, agree on the acquisition data that each person would be required to capture, share the data with those that are better on processing and jointly create an image that we will be happy with. And why not, if we are really happy with it, to submit it for an APOD or Astrobin POD as a joint effort.

I would assume that having more people acquiring data for the same target but, each person to focus on one filter (if it is a narrowband target) or one part of the night sky (if it is a mosaic), it would provide more data to work with. I have seen some great images from other people collaborating on Astrobin (for example), that they produce some genuinely stunning images.

Dear moderators - if you feel that this is out of context or placed at the wrong forum, please feel free to manage it accordingly. Thank you 🙂

One night - one target - no filters!

This is my take of the Shark Nebula (LDN 1235), over one night and justo over 5hrs of data. Captured with the RedCat61, 2600MC and AM5, processed in Pixinsight without overthinking the processing part that much and focusing on the actual target. This is the cropped version as I wanted to focus mainly in the dark nebula. I will be working on the wider photo at some point.

61 x 300sec

50 calibration frames each for flats, bias and darks.

Feel free to provide feedback 🙂

11 hours ago, symmetal said:

The optimum exposure time is reached when the camera read noise is swamped by the sky background noise. A sky background noise of 5 x the read noise makes the read noise contribution to your image negligible and it can be ignored. Once the read noise contribution is negligible then there is no advantage in exposing for any longer, and it's best to start another sub. Exposing longer than necessary makes any tracking errors more noticeable, along with more possible star bloating.

I've previously made a chart for the ASI2600 which I assume you're using as you say ASI200 in your first post. 🙂 You just need to expose until the sky background ADU level as shown by most capture programs when you hover over the image background, is at least the ADU value indicated.

I've made it for different gain settings, though modern ASI cameras where their HCG mode is only enabled above certain gain settings, means fixed gains are more generally used. If you're using default gain 100 and offset 50 then a sky background of around 717 ADU is how long you need to expose for to swamp the read noise by a factor of 5.

This ADU value is independant of the focal ratio or filter used, as a slower scope will need to expose for longer anyway to reach this sky background ADU value, likewise with narrowband filters.

In theory separate optimum exposures are needed for R, G and B filters that's too much hassle so choose one exposure for all, perhaps based on blue. Then make the luminance exposure about 1/3 of the colour exposures.

With a OSC you can only use one exposure anyway, and the median value of the image, usually displayed in the image parameters, is generally a good figure to use as the sky background ADU value unless you want to examine the separate RGB pixels.

For doing a test exposure choose a sky with little nebulocity and no Moon, to determine your optimum exposure, and use this for all your future imaging, with this camera and gain setting. 🙂

I forgot to mention that higher light pollution will mean shorter exposures before this sky ADU is reached, compared to a dark site, so if you move to a site with different light pollution you'll need to redo your test exposures.

Oh and great image by the way. 😊

Alan

Many thanks Alan - i will most definitely read through this properly tonight. I am very interested indeed!

p.s. I have corrected the camera model to ASI2600MM 🙂

50 minutes ago, Phillyo said:

With newer CMOS sensors, more shorter subs are generally better than less longer subs. Gone are the days of old CCD 20-30min sub lengths due to the read noise. You only really need to do enough to swamp the read noise by a certain amount, then anything more is just collecting light pollution. There are other benefits of shorter subs like less requirement on the guiding/mount, more subs to integrate means better rejection of satellite trails and if rogue clouds pass over you only lose 5 min rather than 10 min of data for example.

There is the downside of more subs requiring a more powerful PC or longer preprocessing times. However, all that being said...astrophotography is a hobby (for most of us) and is there for our enjoyment. If you are getting the results you like and are enjoying what you're doing, then I would suggest carrying on with what you're doing as that's the moist important thing

I see - is there any tool to “calculate” optimal exposure time for a specific focal ratio, taking under consideration the camera chip?

1 hour ago, Phillyo said:

Beautiful image! Curious as to why you're shooting 10min subs with the Redcat61 and the 2600mm? Or was this just an experiment to see if the AM5 could manage 10min subs?

I have found that 10-mins subs collect more detail than e.g. 2x 5-mins subs. It just works for me, I have a library of darks and bias calibration files and I have never bothered since my old OSC days to experiment with different exposure times. Probably for OIII, longer exposure times seem to collect more data/ detail. Do, you suggest that 5-mins might be better? 

Finally! After 7 weeks, last weekend we managed to get a couple of clear nights.

I had the Lion Nebula in my list for some time now but, I wanted to wait until it was high enough in the night sky to capture as much data as possible. Lately I am using the WO Redcat61 in combination with the ZWO ASI2600MM + Antlia 2.8nm NB filters and I am super happy with the result, with almost pin-point stars end-to-end.

Here is the result of 14 hours total integration time:

• Ha: 30 x 600sec
• OII: 27 x 600sec
• SII: 21 x 600sec
• RGB: 20 mins each (for stars)
• Calibration frames: Darks, Bias and Flats

p.s. The ZWO AM5 is an absolute gem - offering very good guiding at 10-mins subs consistently. 

And it is getting better by the time…..now driving a Redcat61 and full narrowband imaging rig.

Looking forward to see if ZWO will eventually launch an “AM7” with larger payload capacity. Otherwise I will definitely get a 2nd AM5 for my 2nd rig.

17 minutes ago, tomato said:

That is Clear Outside, powered by First Light Optics, no less.

Thank you!

3 hours ago, fwm891 said:

Yes it can - I've got green bits 😀but not in the right places 😡

Hi - a bit out of subject (sorry!). Which weather app is this? Thanks in advance

The star field and the dark nebula + reflection nebula are absolutely beautiful and the framing even better! Well done 🙂

Very nice Emil and very sharp. Good job!

On 10/09/2023 at 19:18, 900SL said:

Thats quite something. Difficult target that I am not worthy to tackle at this point in my progression. Well done!

I am definitely not an expert on processing - I just put as many hours as possible (wherever possible) and then prey that the processing will be good! 🙂