Detecting a galactic bridge in Ha (Failed)

[Atmos (Colin)]

On Friday? Dana suggested that someone should try to detect a potential bridge between the LMC & SMC. Being too lazy to drive to Heathcote on Monday night (work night) I decided I'd see what I could do from Melbourne with a 3nm Ha filter. It was first light with my widefield setup, QHY163 and a Sigma Art 85mm.
On that note, what do you do when your simple widefield setup weighs as much as your mounts CW Shaft alone? You make it heavier! Yes, 5 ADM plates

Anyway, here is a link to the failed attempt. Most of the variation in the background is due to the subs not being long enough. Only 65 ADU where it should be closer to 300 ADU to be read noise limited.
http://www.astrobin.com/308318/

What I learned is that 180s exposures at F/3.2 is no where near long enough. I think I need 900s :/
So, tonight if it clears as predicted it'll be 900s, F/3.2 and 1.9e- read noise.

[strongmanmike (Michael)]

Cool setup that Col

Mike

[Slawomir (Suavi)]

Yes, very nice setup Colin and interesting investigation

[Atmos (Colin)]

I figured I could at least give it a shot with a Ha filter and see what happens. Granted, 2.8 hours with a 26.5mm aperture telescope isn't a lot of aperture

What does have me a little confused is that with the ASI1600 at Unity Gain (1.6e- read noise) and a F/5.21 telescope with 400s exposures I was over read noise limited by looking at ADU values.
With the QHY163 at Gain 80 (~75 with ASI1600) and a RN of 1.9e- @ F/3.2 I need significantly longer exposures that what it says on paper.

This has me thinking that either the aperture blades haven't locked in at F/3.2 or having such small aperture has having an effect on it. Either way, I do want to see how 600-900s exposures go tonight.

[blink138 (Pat)]

how exciting colin good luck fella, can't wait to see what is captured!
pat

[atalas]

Bummer....more aperture Col.....nice mount

[SimmoW (SIMON)]

I have a solution for your balance - get 5 other lens setups and it'll work fine, maybe even detect your target!

[RickS (Rick)]

You definitely need to go harder, Colin

[Atmos (Colin)]

Originally Posted by blink138

how exciting colin good luck fella, can't wait to see what is captured!
pat

Nothing so far

Originally Posted by atalas

Bummer....more aperture Col.....nice mount

Hopefully next new moon I'll be getting a lot more aperture and time onto it

Originally Posted by SimmoW

I have a solution for your balance - get 5 other lens setups and it'll work fine, maybe even detect your target!

If you can get me four more cameras and lens' I'll do it!

Originally Posted by RickS

You definitely need to go harder, Colin

If at first you don't succeed, try again!

[Regulus (Trevor)]

Well, it's the thought that counts.

Trev

[multiweb (Marc)]

Originally Posted by Atmos

On that note, what do you do when your simple widefield setup weighs as much as your mounts CW Shaft alone? You make it heavier! Yes, 5 ADM plates .

That's a good idea. I had the same problem and added two guide scope rings after the camera but that looks way neater.