Gain settings for ASI174MM cooled

patrickduis

I recently upgraded from an ASI174MM uncooled to the cooled version. With the uncooled one I used a gain of 200 (0-400) and corrected noise with bias/darks.

What settings for the gain do you use for:

- planetary work (short exposures)

- deepsky short (60s for stars for example)

- deepsky medium (300-600s)

- deepsky long (1200s, for narrowband imaging)

Many thanks,

Patrick

Myrtha Observatory Holland

Sam@ZWO

What settings for the gain do you use for:

- planetary work (short exposures)

that depends on the target brightness, I always try to make the camera can run up to 30fps

then adjust the gain to make the histogram reach at least 60%

- deepsky short (60s for stars for example)

for short DSO Imaing, you can use 200-300 gain

- deepsky medium (300-600s)

I think should below unity gain

- deepsky long (1200s, for narrowband imaging)

of course 0, but I don't recommend you exposure so long

patrickduis

Ok, thanks for the fast answer. I will test this the coming weeks.

patrickduis

Hi Sam, here's a pic I shot recently with the ASI174MM uncooled version with the gain setting to 200.

I'm still fiddling a bit with the distance between the Intes Micro reducer and the ASI174MM sensor....even with my new ASI EFW and TSOAG9 I'm still too far off......

TelescopE: Intes Mk67 150mmF12 ON astrosystems.nl montering

Camera: ASI174MM (uncooled)

Autoguiding: off axis WITH Lodestar SXV/PHD2.6

Reducer: Intes micro 0.6x

Filters: Baader 1.25" 7nm Halpha, R, G en B.

Exposure: 20x1200s Halpha, 10x600s R, 5x600s G en 6x600s B, calibrated with bias, darks and flats

Acquisition & calibration/pre-processing: Nebulosity4

Post-processing (registration/integration etc.): PixInsight & Photoshop CS6 (final touch)

Just to give you an idea of what the ASI174MM is capable of when not cooled, and remember, those nights were hot in August, all around 15-20 degrees C.

I'm currently targeting the Maffei1 galaxy (radiating mainly in IR) in infrared light with the -cooled- ASI174MM I bought last week......very curious what will come out of that.

To get an idea: I also added a 21x300s with gain @ 200 image of NGC281, but now in IR light (using a Baader IRpass filter) Still, the IMX174 sensor manages to catch signal here..

Sam@ZWO

very nice!

einari

Really nice.

Would have thought that a lower gain setting would be better with such long exposure.

patrickduis

Ik need to test a few other gain settings with this camera. First tests I will do with the 174mm cooled is testing it on objects that mainly radiate in IR.

johnk

From the tests I conducted in MaximDL, a UnityGain of 200 and offset of 38 is the numbers I came up with as the best settings. Based, on this, below is a link to an image using these settings:

https://www.flickr.com/photos/johnkazanas/30018360373/in/dateposted-public/

patrickduis

Thanks for the testing, nice picture. I was not able to test in the last weeks because of lack of time and cloudy weather. I'm going to use the gain setting of 200 as a starting point.