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This was meant to be M31


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But it appears to be M32 instead :) That will teach me to try to find objects without moving the focuser...

But anyhow, I had a pig of a time getting DSS to stack this one at all because of the lack of stars and it appears to have done a horrible job. It looks more like something that might give you 'flu. Should I be using something else for stacking with this sort of image?

SPC900 again, 32 x 30s exposures with darks.

m32.png

James

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It probably is M31, the core is the brightest part. What sort of focal length and magnification are you working with?

Keep with DSS its free and works well, maybe a bit slow (only tried it on fairly new laptop) to process.

It didn't work for me at first either but I had to go and update for a beta (can't remember why) after a google search came up with the reason it wasn't working. (Maybe it was incompatibilty with my camera?)

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  • 1 month later...

Hi there - I'd agree, this is the centre of the core of M31 - I just took a quick screen shot of the FoV representation of an SPC9000 through an ST120 and this is what you get:

m31screen.jpg

Playing about FoV, in order to get all of M31 onto the chip of an SPC9000, you'd need a lens of about 100mm FL, but I don't know how you'd plug the webcam into it! This would be pretty difficult to process as it's virtually all core... With that combination, I'd suggest going for a smaller target, or using a smaller scope :smiley:

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Hi James - I actually checked out the FoV with a 9x50 finderscope - It's still too big (210mm FL), but you'd just about get all of it with a 4-pane mosaic. If there were a way of attaching it, you might just get away with a single shot using a 6x30 finderscope (122mm FL) :smiley:.

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If we actually got a significantly greater number of clear nights un the UK, that sounds like a challenge that might be fun to attempt. The outer diameter of my 6x30 finder even looks very close to 1.25", so it shouldn't be at all hard to fit a webcam to it. Perhaps if we get an entire month of clear nights...

James

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You would be better off using a 50mm F/1.8 lens, I think. The problem is not just FOV, I am not sure the gain and offset settings were such that the fainter parts were captured at all. It is tricky, you do not want to saturate things, on the bright side, but you still want to capture the faint stuff.

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  • 2 months later...

I love widefield images - It's really nice to see entire constellations and the star fields in which objects "float" :smiley:.

I suspect that you could get some more detail out of both of these with a bit of levels and curves, but you can begin to see some star colour creeping in, especially with the M31 image. There's a bit of trailing on the M45 image, but I'm being pedantic - I come back to how I started - I love widefield images :smiley:.

Just for my curiosity, is your EQ3-2 "driven" (with RA and/or DEC drives) and do you have a polar scope? If not, an RA drive (at least) and a polar scope would enable you to get much longer unguided images with this type of setup... Of course it costs more, but that seems to always be the way of astro-imaging - There's always something else to spend your hard earned cash on :rolleyes:

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Thanks for the response Andy.

I did have a play with the levels in DSS, but am by no means an expert. I don't have photoshop (I use Canon DPP - doesn't do TIFF's)

My EQ3-2 is not driven, I was thinking of getting motor drive(s) for it but now considering an HEQ5 Pro as it has guiding and larger payload capability.

But I've just realised this wasn't taken on the mount! It was taken on a camera tripod, so I guess it wouldn't have mattered what the EQ3-2 has lol.

If anybody fancies a go at the levels and curves please feel free.

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But I've just realised this wasn't taken on the mount! It was taken on a camera tripod, so I guess it wouldn't have mattered what the EQ3-2 has lol.

Yes - That would explain it :smiley:!

If you have the cash to go for an HEQ5, then that would certainly be the way to go as it will give you a fair bit of future proofing (and you could then look at guiding, which would REALLY open up the possibilities)

I have to admit I've not used Canon DPP, but I would certainly recommend you look into buying a good software package for post-processing. I'm a CS fan myself, but there's also PixInsight - They do cost a bit though (but doesn't everything!). For freeware (and again, I've not used it) you could look at GIMP (but please don't ask me any questions on how to use it!)

I did have a go at running a few stretching curves over them both, but even with 21 exposures, as they're only 5s each, you haven't captured an awful lot of photons so the signal to noise ratio is pretty low - I suspect someone else could do a lot better job than I've done here as in stretching them some artefacts have started to creep in (and my skills aren't good enough to control them :embarrassed:). Gradient Xterminator might get rid of it, but for background "normalising", PixInsight's DBE is worth its weight in gold!

M31.jpg

M45.jpg

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wow, that is awesome!

You are starting to see the spirals of M31.

Yeah I'm going to get an HEQ5, but debating whether to get a new scope to go with it as they are cheaper as a package deal.

There is no rush, I've got loads of stuff to keep me busy and away from astro in the meantime and besides I don't think the stars are going to go anywhere...

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