M45

[DavidTrap]

Another humble offering following some renewed enthusiasm for PI processing.

FS-60 with flattener. Slight radial distortion in the corners removed with cropping. Will have to try adding a shim to adjust the distance between the chip and the flattener - hopefully increasing the distance help as I can't reduce the distance without ordering a new adapter from Precise Parts.
QSI583
LRGB - 300second subs at Bin 1x1
Data collected last year at Leyburn.

I have some 30second subs for an HDR process, once I've worked my way back into PI.

Comments welcome as always.

Link to image (http://users.tpg.com.au/dctrap/astrophotos/M45Web.jpg) (950kb)

DT

[jase]

Starting to pick up some great reflection nebulosity David. FoV fits this scene perfectly. Well done.

[DavidTrap]

Thanks Jase,

I think the little wells on the 8300 chip are limiting exposure time. Not sure the budget will stretch to a bigger chip for a while though... Will have to see what I can achieve with HDR combinations

DT

[RickS]

Hi David,

A very nice result showing the power of small refractors.

I think you could probably go a bit longer (and deeper) if you're doing some short subs for HDR.

We imaged this target from SRO with a FSQ-106ED and QSI-683 and got some bloody great big spikes through some of the stars. I think I can see hints of this effect on a couple of your stars. Do you have the integrated OAG? I was told that this was a "feature" of the QSI-583 and QSI-683 with OAG.

Cheers,
Rick.

[DavidTrap]

Thanks Rick,

I have the QSI583WSG which has the integrated OAG, and also the WS cover which is slightly thinner. I bought the WS cover so that I can mount camera lenses on the CCD camera as the WSG cover has too much back-focus. I have used the WS cover with the FS-60, and used the 4 inch refractor as the guidescope.

DT

[RickS]

Hmmm... another data point corroborating the hypothesis that it's a feature of the QSI KAF-8300 cameras.

[DavidTrap]

This image was taken using the non-OAG cover.

DT

[RickS]

OK, then maybe it's something else!

[DavidTrap]

Are you wondering if the OAG prism is the cause of the diffraction spikes?

Might be the ABG being overcome by the bright stars??

DT

[RickS]

I haven't noticed it happening with other KAF-8300 chipped cameras so I don't think it is likely to be sensor related. Definitely looks more like an optical issue than blooming (the spikes seem to occur at a variety of angles.) On the plus side, I have learnt some neat tricks for removing the spikes :)