NGC 4217/4226

[orionoffelt]

Imaged over two nights 20/24-03-18

Luminance of 16 x 600 binned 2 x 2

RGB of 6 x 300 binned 2 x 2

Celeston 11" scope at F 6.3 1764 FL

QHY9m camera

 

Bob

[Demonperformer]

Nice image - you also have a third small galaxy off the end of the biggest one.

[cfpendock]

Very good.  Was this using a wedge?

Chris

[orionoffelt]

Thanks for the feed back. Yes DP I did notice that little galaxy when I checked it out it came up with a strange notation and no other info. Yes Chris it is a celestron 11" CPC on a wedge I get mostly good guiding depending on the position of the target I had another 5 subs of 15 minutes of Luminance but when I combined them it added little to the image just bloated the larger stars a bit so I left them out I have started using binning 2 x 2 for the Luminance which seems to be a win situation with long FL's.

 

Bob 

[cfpendock]

On 3/27/2018 at 20:32, orionoffelt said:

it is a celestron 11" CPC on a wedge I get mostly good guiding depending on the position of the target I had another 5 subs of 15 minutes of Luminance but when I combined them it added little to the image just bloated the larger stars a bit so I left them out I have started using binning 2 x 2 for the Luminance which seems to be a win situation with long FL's.

Thanks Bob.  So, in my eyes, that makes your image even more remarkable - I was never happy with my CPC polar alignment with a wedge so I de-forked it and now use an equatorial, but clearly you have the wedge system sorted.

I also always use 2x2 binning with my CPC for Lum as well as RGB, although some people reckon you can get better results without binning. But, even worse, I don't have the focal reducer so I image at 2800mm FL, which gives me around 0.5 arcsecs/pixel.  Not so good for my UK skies.......hence the binning.  I think that bloating is a characteristic of the CPC series, although I think that some bloating is inevitable at such long focal lengths.

Chris

[orionoffelt]

Hi Chris

I did a lot of work on the wedge and all over the mount fitting aluminium plates to try and make it as rigid as possible I can get decent subs at F 10 on a good day but I think that using the F 6.3 reducer gives me the best results and I wish I had used binned 2 x 2 on my Luminance subs a few years ago. There is a lot of Focal reducers that come up on second hand sights and they are not expensive that's where I got mine from if you want one. I did notice that the 15 minute subs gave me bloating on the larger stars but on another target where the stars are not as big as these were maybe the stars would be okay so I may give the 15 minute subs another try when next out imaging.

 

Bob

[cfpendock]

1 hour ago, orionoffelt said:

they are not expensive

That's what I thought - But then I found the new price is around £650  - seems pretty expensive to me - unfortunately mine is the Edge....I've not seen a second-hand one (for the 11"Edge).

Thanks anyway.

Chris

[orionoffelt]

My that is expensive Chris but it might be a nice Christmas  present ?

 

Bob