AstroGS

Ok this is not during the night but, it is just a couple of hours before tonight's session started. The first evening with clear skies after 3 weeks!

Here is a new version of the same data but, I think the processing is better in my eyes at least.

Back in December 2022 and probably during one of those nights that the weather was unexpectedly good, I managed to capture just under 3 hours of data of the Crescent Nebula but, I forgot to process the image. While I was doing some HD cleanup, I found the data and did a relatively quick integration + processing through Pixinsight. I am super happy with the image taking under consideration the integration time.

Captured 17 x 600 sec + 50x darks, flats and bias on:

Stellamire ED90 Triplet + Stellamira 0.8x Reducer/ Flattener

2600MC Pro + Antlia ALP-T 2" filter

ZWO AM5 + Asiair+

17 minutes ago, tomato said:

An amazing result for 3 hrs integration. However, @George Sinanis, thanks to modern sensitive CMOS cameras and processing software advances, you can capture IFN from the UK under poor conditions, you just need a reasonable aperture and longer integration times.

 

The longest ota I have is the 90mm/435mm ED triplet + 2600mc. I will give it a go with only the LPro filter and see what I can get for 8-10 hours. Sorry Olly for high jacking your thread. I will stop now 😇

4 hours ago, ollypenrice said:

Imaged with Paul Kummer.

Halton Arp was the second most famous astronomer to doubt that Hubble's redshift-distance relation indicated an expanding universe. The most famous was Hubble.  Arp's catalogue of galaxies was part of his one man campaign to unseat the established redshift-distance theory. Here Paul took the RASA away from its usual territory and into galaxies at around 100 million LY. See what you think. True to form, it also found some nice IFN around the Arp 80 group.

This is image four of our crazy week. Sorry!

High res more or less essential for this one:  https://ollypenrice.smugmug.com/Other/Galaxies/i-NjWhSPV/A

Olly

 

 

This is an exceptional image. Very well done!

Could you plz share some details regarding capture time, exposures and filters? I would love to add this one in my to-go list. Although I’m based in the UK and not sure if this is a southern target.

On 08/02/2023 at 07:12, StuartT said:

 

Interesting discussion.

I recently bought an Askar D2 to add in some Sii signal to my L Extreme images. I like the L Extreme very much (despite the halos) as I live in town and it's great at cutting out the bright sky or the full moon. So I was keen to try the D2 as well, but I am very alarmed to see the spectroscopy reports - clearly the Askar QC is pretty abysmal. So far, I've only managed two images combining both filters to make SHO the Rosette and the California. They're ok, but I am not yet convinced I prefer them to the plain old HOO ones I get with the L Extreme (here and here for comparison).

As to the question of mono+FW, I have been thinking about this too. Spending more and more on OSC, duobands etc is probably a bit wasted when I could just take the plunge and do mono (where you have far more control, higher definition etc). I'm still cogitating, so useful to have this thread. Thanks!

Does anyone know where I can get a spectroscopy report on my filter, by the way?

I absolutely love both your Rosette images…. Not sure why but, each one holds on its own. Good job!

On 05/02/2023 at 05:37, Lee_P said:

Not sure about consensus, but I’m happy to share my opinions about the Askar D1 D2 filters. I reviewed them here, and now have even more experience with them. Important caveat: as has been flagged earlier, it appears that not all of these filters are made equal, so there may be an element of “equipment lottery” to be aware of.

I think it’s best to split my opinion about the filters separately. I think that the Askar D1 (Ha/OIII) is fine, but a bit expensive for a 6nm filter. It’s not that much more to buy an Optolong L-Ultimate, which is a decent step up but still, as I’ve discovered, plays nicely with the Askar D2.

The Askar D2 (SII/OIII) works really well to add extra data to your dualband images, and I’ve been having a lot of fun using it. Here are the three images I’ve produced so far incorporating the Askar D2. More details here and  here and here. They’ve got better colours, and I think are just more interesting and nicer to look at, than my attempts using Ha/OIII data alone.

 

 

“But given the price, I do wonder if there's any advantage left over using a mono camera & FW.”
I think this depends on whether you will do purely SHO imaging, or want RGB as well. If you’re only ever going to do SHO then my advice would likely sway toward going mono. But if you want RGB as well; either to image broadband targets, or to add RGB stars to narrowband data, then data acquisition is still much simpler with OSC plus Ha/OII and SII/OIII filters (considering that no filters gives you RGB). This is my approach and I’m just using a filter holder, rather than an electronic filter wheel.

“The downside of OSC + dual band is that without processing wizardry, the images produced by the dual band filters are not as good as SHO images from a mono camera”
You need good processing wizardry to produce decent images regardless of what your setup is, so I don’t personally consider this to be a downside. Processing with Ha/OIII plus SII/OIII filters is a bit trickier than just regular dualband, but it’s OK really. I plan on writing a processing guide when I’ve time.

Finally, without wanting to rehash all the usual mono vs OSC arguments, my viewpoint is that which option is best is dependent on the individual astrophotographer and what they’d find most fun to use. I’ve used mono before, but currently have more fun with OSC. Maybe in the future I’ll switch back to mono. It’s often said that mono produces better quality images, but I honestly can’t tell the difference when looking at final, completed pictures. I rarely look at a completed picture of mine and think “drat, I wish I had a mono camera as that would have produced a better image”; but I regularly think “I’m glad it was straightforward to collect that data.”

These are some absolutely fantastic images - congrats!

It seems indeed that the filters are doing a great job. And loving your reviews @Lee_P

2 hours ago, david_taurus83 said:

1.7 metres in length? Almost 6 foot? Surely not!

It will be my dream to have a 1.7m ota…. You are right. I meant over 0.7m. 

21 hours ago, StevieDvd said:

I was interested in the details of the Rainbow RST-135 as a comparison to my AM5 and came across the youtube video of what happens in the event of a power loss to these mounts - referred to as backdriving.  The video shows several examples of a heavily loaded mount going into an uncontrolled spin. It was interesting to see him put his full image train at risk to demonstrate the lack of a brake and the impact was quickly stopped on any power restoration or simple manual intervention. Even when he allowed it to crash the impact was so slight the sponge around the tripod leg was sufficient to bring it to a halt.

So the AM5 only having the RA brake is not such a negative on this kind of mount.

 

 

Nice video and it demonstrates the risk with this type of mounts. Nevertheless, this is a 12-13kgr rig (including camera, reducer, guidescope and etc.), which in my opinion is not the right mount for regular use with this type of OTAs. 

I would probably use it in specific occasions (e.g. a star party where I want to get my larger FL OTA) and at the same time I do not want to carry a heavier mount (e.g. EQ6R Pro) but, definitely this is not the right mount for me to use with such heavy ota’s on a regular basis. Why am I saying this? Because in those situations where I would want to use my larger FL and heavier OTA, I would always use the counterweight even if the manufacturer is “confident” about their mount’ specs. I wouldn’t mess with physics laws and especially when I have a £6K rig on it 😉

I am also starting to read that ZWO will start suggesting counterweights for over 10kg, moving forward for the AM5. My heaviest rig till now is the Stellamira ED90 triplet, which weighs 7kg, if I remember well, with everything on it; my concern here though is not the weight but, the length. It is over [edited] 0.7m in length. Next time I get this ota in use, I will perform some tests and see how the mount behaves.

24 minutes ago, Elp said:

@George Sinanis I had a few queries and checked with ZWO, the am5 only has a brake on the RA and not the DEC in case of a power loss. In your experience is this an issue?

Apart from once that the power cable was pulled from the Pegasus power box while I had my Redcat on, I never experienced a power loss while using the heavier Stellamira. 
 

But this is not something that would worry me to be honest. 

Recently I bought a 2nd hand ASI1600MM with a EFW and LRGB/SHO 36mm ZWO filters.

Managed to get a couple of cloudless nights but, with not the best seeing and with the moon being 100% full on the 2nd night. This was not the easiest and definitely it as not planned properly as I ended up throwing almost 40% of the OIII data and about 25% from the SII. 

Managed at the end:

• 27 x 600 sec Ha
• 21 X 600 sec OIII
• 14 x SII sec SII

Equipment used:

• Redcat51
• ASI1600 + ZWO SHO 36mm filters
• AM5
• Asiair+

Processed in Pixinsinght - feel free to share any feedback or input. Although I did play around with curves, the image depicts the actual colours after the integration! 

22 hours ago, gilesco said:

Typically you need to send the mount. I would expect the pier to be provided. They may also provide a PC which you can remotely access.

You could just start talking to a provider and they will let you know how they work.

e.g. https://www.pixelskiesastro.com/

 

Thanks - I’ve sent them an email and awaiting their response.

I am not even sure if this the right place to ask this question so, if the mods need to move it to another place please do so.

I was playing for a long period of time with the idea to use a remotely managed obey, where I will send them my rig and they will host it for a period of time. As you probably noticed, this is a very early stage and I have no clue where to start from or even if that is something that can be done.

Trying to google this (I have not ChatGPT it yet) and I am a bit lost. Has anyone done it? Do you have any suggestions? Would I need to send just the OTA + imaging equipment or do I also need to send the mount and etc. Just starting from somewhere and I will see where this will take me.... Thankyou in advance for any help/ advice/ suggestion 🙂

All the above answers are from very experienced fellow SGL members and they are spot on.

By following people’s advice in here, my first scope was a 6” Bresser Dobsonian (circa £350 new) and then went down the rabbit hole of Astrophotography. I always recommend to people that want to get into astronomy, to start with a Dobsonian scope - a 6” or 8” will be the best choice in my opinion, that helps to get familiar with the night sky while, learning your way around stuff.

Since then, I moved to an SCT CPC925GPS, a WO GT81 refractor and today I’m the proud owner of a Redcat51 and a Stellamira ED51 Refractors + a SkyWatcher 150D. Every single telescope that I sold, I regretted it at some point as each was very good on different things.

The Dobsonian is my personal must to have, regardless the number or quality of refractors or reflectors someone has. Why? Nothing can beat the ability to view the planets or the moon through your own eyes. During the summer, while my AP rig images a nebula, I will always have fun with my daughters observing the moon or the brightest clusters. You do not need an expensive one - you can even get an 8” one for less than £250 in 2nd hand market.

I loved the CPC925 (SCT) as it was the best telescope I ever had to view planets and the moon. This type scopes provide high aperture at a reasonable price.

A short field of view refractor - like the Redcat51 - is very good and forgiving for AP. 
A medium FOV refractor - like the SM ED90 Triplet - is very capable for AP and visual.

My very last advice here though is the following - and something I’ve learnt the difficult and expensive way: is to spend more money on the mount than the actual telescope, if your aim is Astrophotography.

1 hour ago, Elp said:

Having tried imaging at 300s as a limit myself, I haven't really noticed a difference going down to say 60s but taking more of them. With my faster systems taking 30s down to 15s subs I normally multiply the total amount taken to account for the change.

You are shooting with a C6 hyper star - correct? Those SCT+Hyperstar/ RASA designs are in my head for some time now...... The RASA8 is in my shopping list.

I have never gone below 120 sec, the best SNR for me with the Redcat/ASI2600MC was always the 600 secs. But, I have never images with a mono before. It will be actually my first proper evening tonight.

41 minutes ago, Simon Pepper said:

I ran a test on this target using 1600mm pro and redcat 300s, 600s and 1000s and the best SNR was 600s. This was on the 21st of Nov 2021 no idea on the moon phase at this point but you could roll back the date on Stelarium and see. I would probably stick to 300s or even less with the moon being full maybe 180? It depends on your filter as well I wouldnt bother with Oiii at all stick with Ha the smaller the pass the better. Good luck!

Interesting input - thank you.

You were shooting with a full moon back then (21/11/2021) - here is screenshot from that night 😉 . I am using the ZWO 6nm 36mm filters.

I would give a try (starting with Ha) at 600 secs and review the first subs before to commit on the whole session on that exp time.

I am seeking some advice for tonight as I am planning to image the California Nebula in narrowband with the Redcat51 + 1600MM.

The skies are supposed to be clear for tonight and a good view hours during the week but, the full moon will make things very challenging. I am chasing this and the Rosette Nebula for some time now but, when we get a new moon the skies are cloudy and when the skies are clear..... you know what I mean.

So, ideally for these targets I would push exposure time to 900 or even 1200 secs (hoping to acquire 20-30 subs for each Ha, SII and OIII) in order to get as much detail as possible and probably 20 x 120 sec subs of LRGB for stars.

My concern is if the subs will be highly impacted by the full moon - especially at those long exposures? I am actually trying to figure out if is should go at all for that target and if yes, should I go for long exposures or shorter ones, due to the moon?

Below is an image from Sky Safari on the target vs moon.

And it will only get worse….. Is this the inevitable consequence of evolution?

https://www.theguardian.com/uk-news/2023/jan/24/londons-msg-sphere-concert-venue-comes-one-step-closer-to-reality

This is probably my 3rd take (and last) of this beautiful comet hence, the "another new new".......

This time I managed to acquire an hours worth of data (60 x 60 secs) on the 31st of Jan and before midnight. Unfortunately the 2nd set of subs - 120 sec each - was n to usable as the core of the comet came out elongated on each frame. At least this time, I am happy that both the tail and anti tail seem to be visible. 🙂

The guiding this time was really good with sub-1" RMS error. Used the Stellamira ED90 triplet on an AM5, with an ASI2600MC and this time a 2" ZWO UV/IR cut filter. The latter is really good and I think it does a better job compared to the L-Pro.

Integrated and processed in PI + Blur/Star/NoiseXterminator.

2 hours ago, Elp said:

But you can use a CW with the am5 to increase its payload right if you wanted to?

Yes but, I wouldn’t push it to be honest. Even the length of the tube can be an issue, especially close to zenith. 
 

But 100% I wouldn’t use the AM5 on the carbon tripod for anything longer than 80-90 apo. 

20 hours ago, DSviewer said:

Many thanks all really appreciate the information I also have to work as well so having something that I can quickly setup is a boon to me especially as my wife would no doubt be very unhappy about me leaving an EQ mount in the house. I have a very secure garage by the house but wasn’t sure about the camp I guess I can put a tarpaulin on. Sorry quick question the HEQ 5 is lighter in believe and would accommodate a WO 81 Air guides open etc but if I wanted I go to something like 120 -130 focal length apo the. Not sure if this would be able to cope with the weight correct?

Having owned an AZ-EQ5 myself with the GT81, I can say that the AM5+tripod+no counterweights is significantly lighter than the EQ5+tripod+counterweight. The cost from the other side is significantly higher for the AM5 for sure.

Personally I wouldn’t mount a larger than a 100APO to any of those mounts. My current 90APO rig (including guidescope, camera and etc) weighs approx. 8kgr. For something like a 120-130 my base would be an EQ6R at least.

A great detailed image indeed - well done. 

Well, I used to have a very good EQ6R Pro, which I sold to buy a ZWO AM5. The main reason was that I am travelling a few times a year and I wanted a better (to the AZ-GTi) mount while away but, also one that would be easier to setup during each session. I have done a review on the AM5 vs EQ6R in this section of the forum, in case you wish to read it (https://stargazerslounge.com/topic/404888-zwo-am5-experience-and-lessons-learnt/).

My EQ6R pro was guiding consistently around 0.6-0.8 almost under any circumstance, carrying both my old WO GT81 and then the Stellamira ED90 Triplet and Redcat51 without issue and was great. BUT! Since, I do not have an obsy, my imaging sessions were becoming less and less frequent as I had to carry the tripod in and out, setup everything, PA and etc. Usually, it would take me 30-40 mins (if everything went well) to start capturing my first sub. That means that during the working week I wouldn’t even try to set it up and the clear skies over the weekend were less and less. As they say the best equipment is the one you use more often.

Thus, since I got the AM5 I am imaging almost every evening there is a clear sky. Why? It takes me only 10  in’s from the moment i decide to start imaging until I start acquiring the first light. The mount is on the tripod and it can be carried with one hand (check though my comments on the mount).

It can carry with ease both the Redcat 51 and the Stellamira 90 triplet and without any counter+weight. The latter weighs just over 8 kgr, including all equipment on.

I love the AM5 and it is one of the best buys for me - have I regretted that I sold the EQ6R? yes, I did as now I can have a semi permanent tripod in my garden and the EQ6 would be perfect fit for it, allowing me to keep the AM5 as a secondary/ versatile/ mobile mount. But, if I wouldn’t have the option for a semi-permanent tripod, I wouldn’t even think to have the EQ6 over the AM5.

Had the chance a few weeks ago (and before the tail started to form) to capture some data of the C/2022 (ZTF) comet.

I was not sure what was the best sub-frames exposure time and shot 60 secs and 120 secs. Managed to get 30 (26 usable) 60 secs and 16 (14 usable) 120 secs subs. Calibrated with Bias and Flats.

Processed in Pixnsight following View into Space tutorial https://www.youtube.com/watch?v=8pnMkzkn5Xw&t=1024s

Stellamira ED 90 Triplet + Stellamira Flattener/ reducer x0.80

ASI2600MC + 2" L-Pro

ZWO AM5

I do hope we get a few more hours over the next week or so and manage to capture its gas/ion tail properly.

14 minutes ago, Lee_P said:

Thanks for pointing me toward this thread. Just tagging @powerlord too as I know they're interested in D2 images. 

It's a shame to hear you had a bad experience with the L-Ultimate. Maybe you had a dodgy one? Mine is good.

Regarding your Spaghetti Nebula image above, that was D2 only, yes? Is the red the SII?

FYI I've written a review of the Askar D1 D2 filters here, and have so far made a Heart Nebula photo with the D1 and D2; and a Soul Nebula photo with an L-Ultimate and D2.

 

I will make sure I read the review over the next days. Thank you for sharing. 
 

the above image is indeed only D2 SII/OIII. So I would assume that the SII is the red part of the Nebula.