Horsehead + Flame QHY9/FLT132

[Grahame (Grahame)]

Another work in progress here, so far two good nights worth of data (with a few rejected) looking alright so far with the exception of halos round Alnitak

QHY9 @ -25deg
R,G,B 7x 300sec all bin 2x2
Lum is 7x 900sec and 2x 600sec all bin 1x1

Darks subtracted and processed in CCD Stack/Photoshop CS5

Link to hi res version here

Cheers,
Grahame.

[Lester]

Hi Grahame, your image is very good with great potential. Just a tad purple IMO, still very nice.

[TrevorW]

Looking good Graeme, a few late nights then

[Grahame (Grahame)]

Yeah just a few Trevor, last night I was testing out pulse guiding through gemini.net drivers which worked a treat.

perfect excuse to spend a few hours on the horsehead

Grahame.

[Alchemy (Clive)]

Shaping up well so far, will ask a couple of questions as I am looking at getting the qhy9 and I have the same scope as you.
Offset and gain settings
15 min subs..... How far can you generally go given you are using f7
Are the filters par focal
Can you put up a 1:1 crop of just a starry area
Isee you have mixed your light time lengths... Not something I have done due to calibration, yournstacking routine may be able to do it i dont think dss does, I assume this image is fully calibrated? Bias flats ?
I believe the ccd chamber is sealed.... So will one set of flats work forever?
That's about it for the questions

The image is shaping up well it seems. Very smooth in the Ha regions, that star seems to be a problem for most scopes one way or another, I'm assuming it's the result of reflections off glass surfaces, you seem to have 4, RGB and another larger one.... Interesting that the rgb reflections are not aligned. You could probably do a color range selection on the halos and desaturate them to some degree. The purple just seems in a larger one not across the image ... Well to me anyway. Given I have the same scope I guess id get exactly the same result..... Worth knowing about.

Cheers Clive

[desler]

It really is coming along nicely Grahame. Alas I have no idea how your going to handle the Halo's although I will be interested to see what solutions you come up with.

Just one thing for Clive :

The Qhy9 does have a sealed chamber, but no, one set of flats won't work, any dust on the filters, or scope surfaces needs to be accounted for as well.
Also, camera rotation within the focuser alters the view through the optics field.

I've been playing around with my light box and have fitted a pot??? (variable resistor) and a series of resistors in series in the positive power lead to get the light source scalable enough to dim it sufficiently to allow the shutter in the luminance channel to get out of the way.

I'll let you know the details when I get it humming along, basically it's been four wet and stormy nights with me in the garage with everything set up and taking exposures, changing some stuff and then doing more exposures till it seems to work.

Good luck


Darren

[ballaratdragons (Ken)]

Grahame,

two things jump out at me immediately.

1. Colour - I actually like your rendition rather than the ones that lift the colour through the roof in bright Red Neon hues.

2. Focus - Man, that is sharp

A very pleasing image to look at

[Grahame (Grahame)]

Offset and gain settings
15 min subs..... How far can you generally go given you are using f7
Are the filters par focal
Can you put up a 1:1 crop of just a starry area
I see you have mixed your light time lengths... Not something I have done due to calibration, I assume this image is fully calibrated? Bias flat?

Hi Clive,
Offset and gain settings are very much unique to each camera. My settings are offset 116 and gain of 1 but this will be different to yours for sure.
I haven't done more than 15 min subs yet but i will try next weekend
The supplied filters with qhy9 were all par focal, however I am using Astronomik type 2 filters now.
I will do a full frame 1:! next week also - the horsehead only has a very small amount of cropping applied.
With the calibration im using only dark's, no flats and bias has been corrected in the master dark's in ccd stack.

It is interesting that the RGB reflections are not centered either.. i'll do some looking into the position of the filters in the filter wheel on that one.

Yep, Darren is right about the flats too - they must be done after each imaging run before the rig is split up (if you done have a permanent setup)
to account for any dust etc that finds its way onto surfaces within the light path.

Cheers Ken! I have now adopted a routine of hourly focus (needed or not) using a bhatinov mask. usually only a very small amount of adjustment is needed but until i get some kind of robo focus happening its the only way to get great results.

Grahame.

[OzRob (Rob)]

That's a great image!! I will be looking at doing something similar with my FLT110 and QHY9 over the next few months so it gives me some much needed information.

[multiweb (Marc)]

Missed that one. That is one stunning shot! The focus is excellent and the colours superb. Very cool.

[mill (Martin)]

Nice looking picture Grahame
With the horsehead it is better to take long exposures than short ones.
I have done some 50 Minute exposures with the QHY9 and it goes well on galaxies.