PadrePeace

2 hours ago, david_taurus83 said:

I think the GT71 might be a bit much for the SGPro. 

That worth stating for sure as the heavier your rig the more strain on gears and the like. That’s why mine was balanced very carefully for each session. The WO71GT is only 2.2kg so I guess it’s all about what you are going to add to that. As I understand it the SGP 5kg limit is for imaging as I cannot see anyone doing visual work with it so working in the 3-4 kg range would be a comfortable upper end target.
Balance is important as is the length of the rig as inertia is a consideration. That said mine guided through PHD to 0.40 arch seconds on RA which I’d say endorsed it for me. 

12 hours ago, drivera said:

Thank you so much for sharing! This is extremely extremely helpful!
I'm amazing it's 4.5kgs with that setup, that's great. I was guesstimating my weight with the 71GT around 4.5 too.  It's great to see you got it working and set up and getting 4mins.  It gives me confidence!  I was thinking I'll go and place the guidescope on the counterweight side too to reduce the it if needed, but maybe not needed?
I'll be technically a few hundred over budget if i did the 71GT but feel it would be worth it in the long run?

RE: Telescopious - thanks for sharing that. I've been going over and over on that with subjects etc, but I'm so new to this that I think I've done it wrong - not including the flattener and how that impacts FOV/reducing it?

 

Talking weight, I do have a autofocuser and a filter wheel which you most likely won’t need given the 533 is a colour sensor. Without those  I recon you’d save close to 800g over my setup which is significant. There are some very reasonably priced (SVBony on EBay) mini guide scopes on the market which will help reduced bulk and weight. You could pay three times the amount but at the FL you are talking about here the EBay ones will perform fine. Every little helps as they say. 

Here is a screen shot of the telescope tab. Once you have loaded and saved your native scope details into the app you just need to set the reduction amount located at the bottom of the tab, in this case it’s a 0.8 reducer (if barlowed it would be something like 2.0, 3.0) and turn the setting on or off to change your image effective FL and hence FOV, pixel scale et al….

Hope I’m not teaching you to suck eggs but try putting the various scope FL options and the 533 into the Telescopious Telescope simulator which will allow you to see the framing of almost any target you might think of. It allows you to rotate framing plan mosaics and use the native and reduced FL as well. It reads out Dawes limits, pixel scale, FOV and target coordinates which is helpful to assess almost any combination of gear. 

I have a 71GT and have mounted it with an ATIK 460EX on a Sky Guider Pro. Fully rigged with a filter wheel and focus cube as in the picture it weighed in at 4.5kg which is pushing the 5kg mount limit. I have shot images with this rig reduced to 336mm FL and got good 4 min guided subs but I had it all very meticulously balanced which gave the mount a fighting chance. 
 

Hope this helps

Adam, can I ask how you removed the stars and their diffraction spikes as I am looking at the same scope but would like to be able to process nebula separately from the stars? I use Straton for my refractor work but haven’t found anything that removes the diff spikes as well.

Great image by the way. 
 

I have the ASI224 and 294 and both accept a 1.25” IR cut filter right in front of the sensor. There’s a step down adaptor ring that comes with the camera to allow for this which screws inside your first adaptor next to your camera judging by the image you posted. 
 

Remember it’s a bit of a punt idea so if you don’t have a cut filter already might be worth borrowing one or get an SVBony IR cut filter off of EBay for £12. 

I’m going to take a wild shot at an IR source given that you had a ring even on your darks. It’s been really  hot these past few weeks. Could it be that your sensor is picking up a warm spot or structure within your optical train? I know this sounds whacky but given Vlad’s observations on the lack of IR coating on the sensor window is it likely that given the multiple mirrors in that RC this might be the IR source?

Might be worth adding as IR filter right in front of the sensor. 

My personal experience with DSLRs and T adaptors is that they never connect to the camera as well as a lens does so you’ll always have some droop or misalignment in the rig. I tried all sorts to sort out my DSLR/WO71 stars issues and in the end I used strong rubber bands to pull my canon up tight to the T adapter to stop it slopping about. 

Of course, it’s a DSLR isn’t it. 

38 minutes ago, Adam J said:

This looks more like a colimation issue to me but the only way is to rotate the camera and see of the worst corner moves or stays orientated to the sensor. 

Try reducing your backfocus slightly. If you can focus using the HFR in your capture software that might give you a sharper image to work with. At F4.5 your focus window will be small so do expect that when focusing. Bat masks are not the best tool with fast scopes in this range in my experience. Go for the smallest/lowest HFR reading you can get. 
It’s not too far away given some. Good luck.  

Following on the heels of my earlier trial on the Pinwheel with the uncooled ASI224MC, I was inspired to shoot this project of NGC4565 Needle Galaxy. It was captured over three sessions 1-6 May 2021, for 8.5hrs of integration, 1000 x 30s subs, 1x1 binned, gain 200 on my uncooled ASI234MC strapped onto my APM107/700. 
This is the first time I’ve attempted the Needle and I’m quite pleased though it needs a few more hours, but that will have to wait until next year as the UK dark window is closing fast now. 
Hope you enjoy this. 
Clear skies

Taken over 8 sessions from 2-16 April 2021. 
Though M101 is a relatively large target it is quite dim and this required a significant effort to get detail into its core. I took 27.5hrs of 30sec exposures which I then thinned down to the very best 18hrs of data removing mostly moon impacted subs. Processed in APP and PS it was tricky keeping the core detail that I had imaged from blowing out.
Lots of advice and lots of very small curves stretches was the key in the end. Hardly sharpened it much with noise reduction undertaken as and when noise just stared to appear during stretching.
As the sensor is biased towards red, colour balancing with green and more so with blue was also necessary.  
Taken at Gain 200 with a UV IR cut ASI224MC uncooled camera, APM107/700 scope on an AZEQ6. 

This whole project started as a trial to see how this scope/sensor combo giving an optimised 1.10as/p would perform especially with an uncooled planetary sensor. I found that it’s a good little sensor if you have the conditions (cold nights) and use Flats, Flat Darks and take Darks every night as the sensor temperature varies being uncooled. For info, I found it ran at about 6 degs above ambient once it was steadily running subs off. 

Hope you like it. 

8 hours ago, PadrePeace said:

I had the same BF issue last night with a ASI294 and a Samyang 14mm set at F4. At full whack I was just out of focus. Tried all the combinations as already talked about but fact is you cannot connect two mail T2 threads together and that’s what it seems to need - less BF than I can engineer out of the box. The ASI and ZWO adaptors cannot give the right BF.  My Samyang 14mm works fine on my canon DSLR. 
 

Anyone solved this one?

I have now fixed the issue. My ZWO adaptor was only 43.5 mm without the 5mm ring and including the 11mm extension ring that comes with the ASI294MC camera. I still don’t believe it but I added only 0.7 mm spacer shims that came with the adaptor to bring the BF up from the adaptor’s 43.5mm to 44.2mm and that has now placed focus on my Samyang 14mm F2.8 lens in the middle of its travel. Such a small change but that’s how to address this if anyone else asks. 
Clear skies all.

I had the same BF issue last night with a ASI294 and a Samyang 14mm set at F4. At full whack I was just out of focus. Tried all the combinations as already talked about but fact is you cannot connect two mail T2 threads together and that’s what it seems to need - less BF than I can engineer out of the box. The ASI and ZWO adaptors cannot give the right BF.  My Samyang 14mm works fine on my canon DSLR. 
 

Anyone solved this one?

2 hours ago, happy-kat said:

Really clear capture.

I'm intrigued by the comments the camera is super sensitive, what are we saying it's super sensitive on please?

It's images like these that really illustrate that you can work with 1 mega pixel cameras. (and it's got big pixels)

By super sensitive I’m referring to the spec of the sensor as written up in its retail adverts on the likes of FLOs site. It is very sensitive to IR, so much so that guys shoot planets like Jupiter in the IR to gain detail you cannot get below 850nm. Also, it’s pixels are relatively big for such a small sensor which are gathering more photons than smaller pixels.

I’m no scientist on this subject but that’s just how I understand it to be for the 224. 

Hope this helps.

49 minutes ago, Cosmic Geoff said:

Great image of the Needle.

I imaged this a few nights ago with the same camera -ASI224MC- and the same aperture - 102mm f5 achromat.  However I was doing EEVA with live stacking, and got 6 frames of 5 seconds exposure each before cloud closed in.   Since the exposure was so much shorter than that used by PadrePeace, the results are not impressive, but I can make out the needle shape, which is a lot more than I can see visually from this locality even with a larger telescope.

I have a question.  What are PadrePeace's skies like, as I find that with an exposure longer than around 5 seconds I am getting sky-glow at this location?

Cosmic Geoff

I’m m lucky to have Bortle 4 or sq of 21..23. I have also rallied the support of my local neighbours who allow me to ‘cloak’ the immediate LED street lights. I tried doing my initial Pinwheel image (also posted on this site) with only 27% moon and ended up throwing up to 12hrs of that stuff away opting to keep 18hrs of proper dark subs instead.
 

This camera is so sensitive that without dark conditions I guess you will struggle. Shorter subs than my 30s ones would be your best defence though with LP about. I also had a UV/IR filter in the optical path to control that part of the spectrum as the 224 is really super sensitive to that so an LP and UVIR filter might be a useful investment for you.
Does this help?

PS…just had another thought that if you are live stacking then I’m assuming there are no calibration files being applied. Without Darks, Flats and Dark Flats my image would be much lower quality. The amp glow (top RH corner) on the 224 can be seen on my screen shot above of my capture screen.  

Thanks to all of you who are enjoying this image. Glad I posted it here as well as Astrobin.

https://www.astrobin.com/umdyyz/?utm_campaign=notification&utm_medium=email&utm_source=astrobin&from_user=3155
It’s a great camera only made better if you could cool it. 

27 minutes ago, vlaiv said:

Ppi used in image really does not change resolution of it when viewed on screen. It is for printing purposes mostly so resolution is still 1.1"/px. At 300ppi image would print 4 inches wide (as it has ~1200px in width) and with 72ppi it would print as 16.7 inches wide.

In either case imaging at 1.1"/px and getting results that sharp (even with a bit of unsharp masking) requires very good seeing and very good mount.

The mount is an AZEQ6. It generally runs under 1as RMS, say .5 at best to .8.   I’d say that the scope balance is something I really focus on even with such a robust mount capacity. It’s a mobile rig so I have to polar align each session using  SharpCap. You can only make things worse by not doing the small stuff right. It’s a very sound mount. AdamJ has the same and gets similar guiding results so SW are doing something right with that mount.

Here’s a screen shot taken during this project which shows the mounts performance nicely.

9 hours ago, Xiga said:

That's an incredible image for what is essentially a Planetary camera. Your perseverance (1000 subs!) has certainly paid off. Touché! 

ps - If you want to see an absolutely insane Lucky imaging DSO image, then check out the one below. He took over 40k of Lights, ranging from 0.5s to 7s. I can only assume he has access to a SuperComputer 😂

https://www.cloudynights.com/topic/568316-m82-full-power-with-short-exposure-t300-qhy5iii-290-m-qhy5iii-178-c/

Thanks for the compliment Xiga. I think this sensor has much more potential and so thanks for flagging up the M82 HDR work at your link.  I’m inspired now to give something like that HDR technique a go but not until later this year now that temps are rising and dark is disappearing. 

10 hours ago, vlaiv said:

Seeing on particular night must have been exceptional.

This is very high resolution image indeed!

Did you use sharpening or is this actual resolution achieved? Star sizes at 1.1"/px are just incredible for ~4" of aperture.

 

Vlaiv, I live in a Bortle 4 zone and seeing for two of the three sessions was very good with all the arctic air we have been exposed to recently. The very cold air helped keep the sensor temp down ivo 5-7degs C. The scope/sensor combo gave me 1.1 a/s per pixel (though this is a OSC) to start with and once I’d processed it I saved the image at 300 ppi rather than 75 ready to upload to my Instagram account which always ruins the detail with its compression so you have to compensate. I did unsharp mask the Galaxy in some places as part of my normal routine. 
Can I say I feel really chuffed that you like it given your significant reputation on this site. Thank you. 
I also posted on this site last month my previous Pinwheel work with this rig which had a lot more integration but is a bit dimmer of course. Hope this answers your questions. 

Shot this over three sessions for 8.5hrs of integration. 1000 x 30s subs, 1x1 binned, gain 200 on my uncooled ASI234MC strapped onto my APM107/700. 
First time I’ve done the Needle and quite pleased though it needs a few more hours, but that will have to wait until next year as the UK dark window is closing fast now. 
Hope you enjoy this. 
Clear skies

27 minutes ago, Adam J said:

You have not defined your performance measures.

However they will both achieve the same SNR in the same amount of time. 

But Jemima may not fit the object into the FOV of her sensor assuming the same sensor. One the other hand if the object does fit into the FOV of Jemima's scope NOAH may be under sampled by comparison depending on seeing. If Jemima is oversampled then she may bin in HW or SW to increase SNR or Perceived SNR. 

If they both have the same FOV and optimal sampling then Jemima will win. 

But one thing is for certain Olly and that is that Jemima will need significantly deeper pockets that NOAH and so theory aside most will be better off...(literally) going with NO AS solution and accepting the potential trade off in terms of resolved detail. In a nut shell that is why most people use a reducer. 

You say above that you don't increase her focal length. Fine but you did reduce Noah's So if they are both to be F5 Jemima must have a longer effective focal length than Noah.

The other big issue with this is that while you can get scopes with almost any focal length you want you can't get cameras with and pixel size and FOV you want. Hence you can't optimise your FOV and image scale to fully match your scope. If you could and kept image scale and FOV the same between Jemima's and Noah's imaging setups she would always win....but you can't and more often than not the camera is the same camera. 

Adam

 

What he just said! Yes… absolutely what he just said 😵‍💫 

3 hours ago, PadrePeace said:

Who supplied this?

Still don’t know who supplied this? 

Who supplied this?

I’m very late to this thread but if any are still interested I posted my first experiment on DSOs with the ASI224MC here.

Hope it’s still relevant to some of you. Would appreciate your thoughts if you have time.