M27 & The Veil Nebula..

[JohnP]

The last few nights I've been playing around with sorting out Autoguiding & have finally got is sussed. Below are a few images taken with EOS300D digital camera through ZS66 SD APO piggybacked on MN56 using my SC3 to autoguide... Cables & connections are getting very complicated. Used to take me 10 mins to set up takes about 45 mins now....

Anyway details of exposures on on the images - As Chris pointed out looks like I need to get a 'fringe killer' or minus violet filter to get rid of the 'star halo's' - It's nice being able to do one shot colour.

The autoguiding works well & on the whole stays within +/- 3pixels all night - I also did some 5min Ha exposures of NAmerican but am figuring out how to process correctly - will post later..

Cheers,  John

[Fay]

John,

you certainly look like you have it sussed, they are great images. No keeping you in now, you will be up all night!!!!!

Fay

[Tony G]

Hi John,
great images and it seems like the SC3 is playing second fiddle to the Canon, but with colour images like that I can see why.
Keep up the good imaging.

Tony G

ps I noticed that you've used Iris, haven't looked at it yet myself and was wondering how you find it (and I don't mean by putting Iris in a search engine and pushing FIND)

[JohnP]

Hi Fay, Tony,

Thanks for your comments - I am just pleased to have sorted out guiding...

Iris is good for handling directly the RAW files from my Canon in 48bit colour format. It is a very powerful program & has some really good algorithms for getting the best out of images etc. however, it is a real nightmare to get to grips with - at least I think so) - it's not what I would call a user friendly program...

The best bit is it's free... comparable prog's such as ImagesPlus cost upwards of £200....

Hopefully, more images to come...

Cheers,  John

[Fay]

Tony, whats these algorithms I keep reading about?

Fay

[JohnP]

Hi All,

I was playing around with my M27 image over the weekend (I decided the original looked a little over processed). I did a less agressive stretch in Iris & also applied a little noise reduction in Neat. The changes are subtle but I think it's better. I'm chuffed with this image (my best M27). If I get a chance later I wouldn't mind trying to add some Ha to bring out a bit more detail in the nebula. I just love the EOS for 1-shot colour.... it definitely beats all that messing with LRGB filters....

Cheers,  John

[Mike]

John - great images.

How do you cope with the light pollution/noise? I tried a few shots with my Nikon recently and found even shortish exposures were coming out very light due to the very light nights at this time of year and any detail appeared to be lost. How are you managing to lose that noise?

[Anonymous]

Hi Mike,

THe Nikon is knows to have a whole bunch of noise issues and amp issues compaired to the EOS.  

The French guys (I can't remeber their names) did a side by side test of the EOS 300D and the Nikon D50, the EOS although it has a CMOS and not a CCD actually won hands down (someone elses finding not mine).  I read the review before buying the EOS.

However they key way to get the exposures is to a) use a broadband LPR, John is using an entry level Baader Neodium filter (I have a spare one if you have £20), Astronomik CLS, Baader UCS, Hughteck etc are ok.

And then take as many subs as you can before the background noise becomes too apparent, I beleieve John is limited to about 1-2 minuts with that filter, with the Astronomic CLS it will be approx 5-10 mins at the expense of colour cast.  At that point I beleieve you will be into Flats with the Nikon to try to remove the amp noise anyway.  In our polluted skies you should take a minimum of 1 dark to ever 4 subs at least to remove the noise.

John has then go into IRIS (very brave man) and just stacks and tweaks.

Thats it..

Chris

P.S. i'll find that review for you to read it was pretty funky.

[Anonymous]

Found it,

The 50D and 300D have the same chips and guts in them, this is the test.

http://www.astrosurf.com/buil/d70v10d/eval.htm

Chris

[JohnP]

Hi Mike,

Thks - Yes Chris is correct I use a cheapo skyglow & light pollution filter - works OK upto about 2 mins at lower ISO's - without it you can barely expose for 30 secs & all you get is a horrible 'redy brown soup....' I tried some Ha imaging the other day & was easily able to do >5mins at ISO 1600. I'm considering getting one of the CLS filters that Chris mentions - It's a lot more selective with what it lets through & blocks it also lets through a good amount of Ha... Only prolem I need the 2-inch version to go with the EOS & ZS66 to stop vignetting & it's over £130...

Cheers,  John

[Mike]

John/Chris - Thanks for the tips. John, how are you connecting the filter the Camera?

[JohnP]

Since M27 is relatively small - I have a T-Mount to 1.25 inch eyepiece adapter - I just use a 1.25 inch filter threaded in to the end of this & then just slide it into the 1.25 inch adapter on the ZS66. Like I said vignetting is fairly severe so I'd prefer the 2-inch option but it's a lot more expensive.

John