NGC4565 Needle Galaxy vs ASI224MC

[PadrePeace]

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

 

Edited May 7, 2021 by PadrePeace

[vlaiv]

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.

 

[Xiga]

1 hour ago, PadrePeace said:

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

 

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/

[Adam J]

Really good image again and so soon after posting M101. As vlaiv says very small stars and great resolution.

Shows how seeing limited everything is as I have seen countless images of this galaxy with hugh scopes fail to captuer as much detail. The short expsoures enabled by that sub 1e read noise do help that is for sure and I have noticed that I get much better detail in galaxy images when going with 30 seconds or lower exposures and stacking based on star shape / quality as I think you did here.

No idea why more people are not galaxy imaging with this camera and whish that ZWO had not stopped making the cooled version of it.

32 minutes 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.

 

I know Padrepeace has an optical report for the scope, but that could send things off into a whole different discussion. 

Congratulations on another great image.

Adam

[PadrePeace]

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. 

Edited May 8, 2021 by PadrePeace

[PadrePeace]

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. 

[vlaiv]

1 hour ago, PadrePeace said:

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.

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.

[PadrePeace]

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.

Edited May 8, 2021 by PadrePeace

[Tommohawk]

Terrific result.... I'd be very pleased with that! 

[teoria_del_big_bang]

What a fantastic image 🙂 

Steve

[peter shah]

Thats superb

[ultranova]

wow stunning .

Well done 

Paul

[PadrePeace]

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. 

Edited May 8, 2021 by PadrePeace

[Cosmic Geoff]

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?

[PadrePeace]

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.  

 

 

Edited May 8, 2021 by PadrePeace

[happy-kat]

Really clear capture.

 

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

 

I edited as re read and saw the comment the sensitivity was referring to the IR 

Edited May 8, 2021 by happy-kat

[PadrePeace]

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.

Edited May 8, 2021 by PadrePeace