Horsehead nebula in H-alpha

Wow, that's one beautiful wide field image with lots of details there Tony! If I may ask Tony; why did you decide not to apply a master dark frame and what operating temperature was your camera?

With best wishes and clear skies
Mike

Kinch wrote:

CarlightExpress wrote:
Got a price for the 3nm ones from Teleskop Service €868 per filter, or €2604 for the three, if I got them from the US it would work out at €570 per filter + Shipping, it's scandalous !!!!! Extra €300 per filter for the privilege

Unsure which ones exactly you were looking at. The €570 equates to about $645 at the moment - but I don't see 3nm filters at that price at the Astrodon site.

$650 per filter for the 3nm 36mm ones

www.astrodon.com/products/filters/narrowband/

Scroll right down to the bottom

Tony wrote: It's definitely moon glow Brendan. Although there is plenty of nebula and dust in that area, it should be a lot darker than the area to the West (top of image). I have read a bit since that even 3nm filters can not block strong moon glow completely.

I seem to recall that Moonglow only affects OIII, I have never been affected by moonglow with HA or SII, and I currently have the 7nm filters from Baader, I was primarily looking at the 3nm filters to boost contrast and really zone out unwanted wavelengths

Thanks Simon - found what you were looking at. For some reason, with the quoted prices at the back of my mind, I was looking only at 50mm filters......and failed to keep scrolling!

Mike wrote: Wow, that's one beautiful wide field image with lots of details there Tony! If I may ask Tony; why did you decide not to apply a master dark frame and what operating temperature was your camera?

With best wishes and clear skies
Mike

Temp was set to -10.00. Apparently the Sony chip in the 460ex has exceptionally low read out noise and most people don't bother with darks, from what I read anyway. But it was my first time testing the camera so darks were the last thing on my mind! Just wanted to see images! I can make up a dark library for future use.

It never ceases to amaze me how images like this are taken these days from a light polluted city, images that were once only possible from a professional observatory on a mountaintop somewhere.

Super image Tony !