All Sky - setup issues

[brenski]

Finally, got my AllSky setup (was hoping this would be ready to go for the Perseids).
However, i’ve hit a snag: The images off the Zwo120mc are a little strange.
there's also the small issue of the hot pixels...
i’ll need to tread carefully with any adjustments – as some settings have definitely increased the number of hot pixels - to the point where the screen becomes a red/green/blue mosaic.

I set the thing up again last night and it did record loads of images. (the attached example) images were taken at 02:47 and 04:35 am)
– however, almost all are too dark to be worthwhile. i’ll need to adjust the settings…but am wary of the hot pixel thing.

i’ve added images of my settings below. if possible i’d like to do a final dry run tonight, prior to the Perseids on tuesday. so what adjustments do you guys suggest (my sharpcap settings are images 3 & 4) – to get the darkest part of night slightly brighter than the final (pre-dawn) image, and the dusk/predawn images noticeably brighter than that 04:35am image.

thanks
[ps - ignore the /avi capture setting, it was definitely set to .png at time of capture]

[admin]

Hi,

I use an Altair camera for my all sky system and I have the exposure set on auto with a maximum exposure of 30 seconds. I also have the gain set on auto with the range centre between 1x in 16x (this is about is equivalent to a gain range of 0 to 80 in ZWO units). Those settings get me reasonable star fields when the sky is sufficient dark.

I think you will have a bit more trouble with the 120MC camera – it is quite bad for hot pixel is compared to the more modern Sony sensors. It may be challenging to find settings that give you a bright enough star field without a lot of hot pixel problems.

Cheers, Robin

[brenski]

thanks Robin

my issue will be those adjustments - too far and the background is littered with hot pixels, not enough and there's almost nothing distinguishable on screen.

i was hoping to get a few hundred 2-sec images and drop them into something like Shotcut to create a timelapse video.

some quick questions:
♦ will i need a dark frame and "subtract dark" option enabled to remove hot pixels?
♦ will sharpcap do this "on the fly" before saving an image? - or is this something that will need doing once the entire capture series has ended.

thanks

[admin]

Hi,

if you use the dark subtraction feature in SharpCap then the dark frame be taken from every frame before it is saved - no need to process afterwards. Of course if you do this you have to lock the exposure and gain to fixed values that match your dark frame.

Recent versions of SharpCap have the option to write to WMV video files which is what I use for my all sky camera – the files come out relatively small due to the compression but the quality is fairly decent.

Cheers, Robin

[brenski]

Hi Robin

thanks for that - all done!

going to give it another go tonight

[admin]

Hi,

good luck! Unfortunately my camera glitched out last night so I only got a very short recording. From what I hear the Perseids were few and far between anyway

Cheers, Robin