How to scare the living daylights out of a ZWO 120mm camera

[tomato]

I'm desperate to try out some closer in galaxy imaging , so Tomatobro has loaned me his FLO Clearance deal ZWO ASI 120 camera and I have managed to lash it to the Esprit 150.

Do you think those little pixels are quaking in their electron wells at the prospect of the lens cap coming off? It kind of reminds me of the Apollo command module perched on the top of the Saturn V, but maybe I should stop eating very mature cheese.

I daresay the results wont be anything to write home about but it will be fun trying.

 

[happy-kat]

What will be your first target?

[Gina]

You might find noise a problem but at least the ASI 120 generates very little heat of its own unlike some other cameras.  Once allowed to cool outside at night in winter the noise is far less.

[Tomatobro]

You holding out on me Bro? I said the camera would improve your guiding. If that's the guide scope what you got hidden in the house that you haven't told me about?

[tomato]

First target will  be some clear sky for Polar alignment, 10 tenths since my first post...

It's imaging at 0.7 arcsecs/pix which is not outrageous, M51 will fill the FOV nicely. I have never run a CMOS camera before so have no idea on gain or offset settings, am planning on doing lots of 30 sec exposures.

[Gina]

Use high gain - more signal less read noise.

[wimvb]

21 hours ago, Tomatobro said:

You holding out on me Bro? I said the camera would improve your guiding. If that's the guide scope what you got hidden in the house that you haven't told me about?

His imaging scope is the small one with blue camera. He's obviously taking his guiding very seriously.

[tomato]

Well, we didn't get very far, the cloud never really went away, and had problems downloading the subs from the ZWO to my rather ancient imaging laptop.  So I am now shopping for another faster computer with a USB 3 port, as the mk 1 ASI 120 does not like downloading 16 bit subs > 1 sec on slower serial connections, it would seem.

But.... Scope Nights and Clear Outside say it is looking good for tonight.?

[coatesg]

On 23/02/2019 at 19:12, Gina said:

Use high gain - more signal less read noise.

Just beware of going too high on the 120 - at very high gains it (for me at least!) introduces some significant fixed pattern noise. On related notes, dithering is definitely recommended.

[don4l]

On 23/02/2019 at 18:03, tomato said:

I'm desperate to try out some closer in galaxy imaging , so Tomatobro has loaned me his FLO Clearance deal ZWO ASI 120 camera and I have managed to lash it to the Esprit 150.

Do you think those little pixels are quaking in their electron wells at the prospect of the lens cap coming off? It kind of reminds me of the Apollo command module perched on the top of the Saturn V, but maybe I should stop eating very mature cheese.

I daresay the results wont be anything to write home about but it will be fun trying.

 

You might find some useful info in this thread :-

 

I'm very impressed with the capabilities of this little camera.  Handling the hot pixels was the biggest issue for me, but you do collect some very useful data in a very short time.

I am still struggling with dark frames.  The only way that I have been able to use them successfully so far is to blend them in "subtract mode" in The Gimp (Photoshop can do this the same way).  I then use the opacity slider to visually determine when the hot pixels are reduced to a maximum without taking away from the target.

 

[tomato]

Well, I used a variety of laptops, from ancient to relatively modern, but could not get the ZWO 120 to download in mono16 mode. Reading the Sharpcap forum, this seemed to be problem on the Mk 1 camera, which most people fixed by using a USB 3.0 port, but it wouldn’t work for me.

So ran it in mono8 and got this result, I am quite impressed given the lack of optimised settings and calibration of the image. If you are on a tight budget, these little cameras have to be worth serious consideration.

[tooth_dr]

Darn tooting that's a nice result

[wimvb]

At high enough gain, the dynamic range of these cameras falls down to 8 stops, so there isn't much to gain with 16 bit anyway. Just take lots more exposures to recover DR.