M51 Hypercam 183 firstlight

[Dragon_Astro]

Luckily didn't have to wait too long to try out my recent purchase, the AA Hypercam 183 Mono :)
Managed to get a bit of time to try it out before clouds rolled in,  capturing a fave of mine M51.

A reported QE of 84%, cooling fan on (not Tec) but still brought temp down roughly 5deg from what it was on start up (every little bit helps).
Very low noise camera, so no amp glow, no darks taken at all.

Sharpcap doesn't seem to like 12bit captures, dropped every frame, so used 8bit mode.
A laptop upgrade maybe needed to use the Hypercams full USB3 speed.

50 x 10s
Simple processing in Astro Art 6, large sensor so view is  cropped.

[Merlin66]

Lookin' good!

Have you tried the 183 with FireCapture?

I was using the ASI 183MM for solar imaging and found FireCapture to work very well for me.

 

[Dragon_Astro]

6 hours ago, Merlin66 said:

Lookin' good!

Have you tried the 183 with FireCapture?

I was using the ASI 183MM for solar imaging and found FireCapture to work very well for me.

 

I have downloaded fire capture, but not used it with the 183 yet.

Will give it a try next clear night

[andyboy1970]

I found that as soon as PHD or anything else was in use on the laptop I got the blue screen of death!

I now use my small netbook for EQMOD and guiding and my laptop (USB2) solely for capture/camera control.

I always use 12 bit captures.

[Merlin66]

The latest CMOS cameras , like the 183/ 1600 etc. are designed for USB3 - fast down load of large amounts of data....

I ended up upgrading to a "Hot" MSI gaming machine, i7, USB3, 16Gb memory and a 1Tb SSD drive to handle my solar images....

(I do have a basic ol' Compaq laptop win7 in the observatory which easily handles CdC/ EQMod/ PHD2/ Astroart the spectrograph and three CCD cameras.....)

 

 

[ollypenrice]

That does look promising. However, you have very saturated cores while there is still plenty of faint stuff still to be found given much longer total exposure. Were the cores saturated at the linear stage?

Olly

[Dragon_Astro]

42 minutes ago, ollypenrice said:

That does look promising. However, you have very saturated cores while there is still plenty of faint stuff still to be found given much longer total exposure. Were the cores saturated at the linear stage?

Olly

Hi Olly

To be honest they were quite saturated, I could probably get away with using a much lower gain setting.

With such a sensitive chip, it'll take a bit of experimenting with settings to tame the beast.

Lower, for longer you think?

[ollypenrice]

9 minutes ago, Dragon_Astro said:

Hi Olly

To be honest they were quite saturated, I could probably get away with using a much lower gain setting.

With such a sensitive chip, it'll take a bit of experimenting with settings to tame the beast.

Lower, for longer you think?

I haven't used a CMOS camera but, from what I've read from those using them, I'd start with unity gain. If you're saturating the core of M51 (which isn't that bright) in 10 seconds then I think you're going to struggle to cover the whole dynamic range in subs at the same setting. (If you brought exp. time down to avoid the saturation surely you'd never* pick up the faint stuff?)

I also wonder if the way forward with these cameras might be to use different sub settings and combine them using one of the HDR techniques available. I always argue with CCD that multiple sub lengths are rarely needed but CMOS cameras are a new breed.

As I say, this is all speculation for me. I'm itching to try a CMOS!

Olly

* Edit: Perhaps I shouldn't say 'never' because someone will appear and say that, in the end, you could! But I doubt that it would be optimal.

[Adam J]

2 hours ago, ollypenrice said:

That does look promising. However, you have very saturated cores while there is still plenty of faint stuff still to be found given much longer total exposure. Were the cores saturated at the linear stage?

Olly

Could be loss of dynamic range by operating the camera in 8-bit mode as opposed to the normal 12-bit mode, combined with short exposures at very high gain probably explains the core being blown out in only 10 seconds. When using the short exposure technique then you do need to set high gain of about 1100 on the Altair Astro...but you really do need to run 12-bit mode. With only 1.3e read noise you really done need exposures longer than 10 seconds and you could actually go lower 5 seconds perhaps, the biggest problem is that 50 is nothing like sufficient. Maybe 2000

[Dragon_Astro]

Having a browse around online and with what you're saying, I'm sure I did (definitely) have the gain set too high.

Tomorrow night is forecast clear here, so will have another try on the same target using different settings

[DaveS]

If you have AA6 then why not use that for capture? It has no trouble with 12bit mode. I tend to run my CMOS cameras in Max DR mode and take 300 sec subs.

[Dragon_Astro]

1 hour ago, DaveS said:

If you have AA6 then why not use that for capture? It has no trouble with 12bit mode. I tend to run my CMOS cameras in Max DR mode and take 300 sec subs.

I'm pretty sure Sharpcap could handle 12bit fine, I think it's more the fact it's USB3 currently going through to a USB 2 port? Unless that's what you're using Dave? If so, maybe I should give AA a try

The 183 chucks out something like 5000 x 3000px subs, even when I dropped to the smallest capture area Sharpcap couldn't handle 12bit...but is fine with 8.

[DaveS]

Yes, I have the 183 going through the USB2 hub in my DDM60 then into my laptop.

[Adam J]

3 hours ago, Dragon_Astro said:

I'm pretty sure Sharpcap could handle 12bit fine, I think it's more the fact it's USB3 currently going through to a USB 2 port? Unless that's what you're using Dave? If so, maybe I should give AA a try

The 183 chucks out something like 5000 x 3000px subs, even when I dropped to the smallest capture area Sharpcap couldn't handle 12bit...but is fine with 8.

That could be your problem the video crop modes are 8 bit only native. if you want 12 bit dynamic range you need to use the full frame of the sensor, if my memory is correct. Of course that's cropping on chip, I suppose it could be possible for software to crop post readout.  I don't think it's a USB 2 / 3 issue. 

[Adam J]

5 hours ago, DaveS said:

If you have AA6 then why not use that for capture? It has no trouble with 12bit mode. I tend to run my CMOS cameras in Max DR mode and take 300 sec subs.

The AA Hypercam is not set point cooled so for a bright galaxy like m51 he is better off using the short exposure method due to amp glow and temperature matching darks. Just needs to work on his settings. 

[DaveS]

Ah OK, sorry I didn't realise that, I use the ASI 183 MMC Pro, which is a rather small sensor for me. I *do* need Darks to counter amp-glow.

[Dragon_Astro]

Seems like it was Sharpcap that had an issue with the 12bit mode, as I've since tried Firecapture and Altair Capture (indoors) and the subs were rolling in fine without dropping frames.

Not able to use Astro Art, as it's only the demo, which doesn't allow saving ?

Fingers crossed the forecast for tonight stays clear.

[Dragon_Astro]

Had another go with this last night :)

Dropped the gain right down, M51 was barely visible on screen.
Managed to get 12bit mode using Altairs own capture software, processed in PS this time using a starmask.
Still not 100% perfect but a step in the right direction I think.

200 x 10s
Dithered, no darks....not sure if darks would help even more?

[Adam J]

On 11/06/2018 at 10:58, Dragon_Astro said:

Had another go with this last night

Dropped the gain right down, M51 was barely visible on screen.
Managed to get 12bit mode using Altairs own capture software, processed in PS this time using a starmask.
Still not 100% perfect but a step in the right direction I think.

200 x 10s
Dithered, no darks....not sure if darks would help even more?

How are you getting on with this now? Personally I would use Darks as eventually with more integration you will see the glow. 

[Dragon_Astro]

Hi Adam,

Yeah definately better than the m51 back then, learnt to set the gain much lower in Altair Capture.

Now using 2 or 3 gain max (thats 200/300 in Sharpcap) so there's no burnt/clipped stars, and yes using darks every time now.

Hoping to get out tonight with a clear forecast, so will post on here sometime