I spy a bubble in the sky! NGC7635

[Darth Takahashi]

Sundays have been prity good to me, allowing a few hours of imaging between 20:00 to 22:00 before the clouds roll in as normal and bring my imaging session to an end.

Here is an 85min image of NGC7635 in H Alpha using my TOA130F fitted with focal reducer, so at approx F5.8.

Weather and seeing were normal for my area of the world, i.e. nothing special .

I hope you like it, I do, these H Alpha images are growing on me, they have a surreal quality of their own.

[RobH]

Great capture Neil, you've gone pretty deep for just 85 minutes. The FOV is perfect.

Cheers

Rob

[Nexus 6]

I certainly do like it Neil

Thanks for posting

Alan

[shaunster]

Really nice

When you say its an 85min image, is that one 85 min image or shorter ones stacked? I would guess its many shorter ones, but you never know..

[Darth Takahashi]

Really nice

When you say its an 85min image, is that one 85 min image or shorter ones stacked? I would guess its many shorter ones, but you never know..

It's actually 17 x 5mins, the run was 20 images but I lost three due to intermitent cloud cover spoiling my tracking etc...

I don't think many people shoot single images of that length for various reasons;

1. Plain strikes

2. Satellite strikes

3. Cosmic rays hits

4. Others including clouds

All contantly conspire to ruin your imaging session. loosing 2 or 3 5 minute images is bad enough but loosing a 1 hour image because of the above would make me suicidal especial if the clouds rolled in!

[oldfruit]

Lovely image, beautifully framed.

[ollypenrice]

Lovely stuff and what a fit on your chip!

If you go for 10 min subs and sigma reject you should find than satellites etc just vanish, assuming a good number of subs, I would have thought. Five mins is a bit of a killer for Ha in theory. But on the other hand the image is a cracker, so what do I know??

Olly

[prokyon]

Very nice!!

I have to do this object soon. Never done up to now. Thanks for sharing.

Cheers

Werner

[LukeSkywatcher]

I could look at images of the Bubble til the cows come home.

Very nicely captured.

Would i find this/see this in my Heritage 130P?

[Darth Takahashi]

Lovely stuff and what a fit on your chip!

If you go for 10 min subs and sigma reject you should find than satellites etc just vanish, assuming a good number of subs, I would have thought. Five mins is a bit of a killer for Ha in theory. But on the other hand the image is a cracker, so what do I know??

Olly

So far I'm playing it by hear...but I'm really loving my Baader H Alpha filter. Only two images into it, this and B33 and both are looking good. I also thought that I'd need at least 2 - 3 hours of data to product anything special.

It will be a couple of weeks now before I can try your suggestion as I have a business trip next week.

[Darth Takahashi]

Thanks for all the great comments... If the weather plays nicely I'll get back to this one soon and add the colour components, cheers

[MartinB]

I've passed a critical eye over this image and can't find a single fault! The stars are pinpoint sharp, round and natural. The brighter nebulosity is detailed with the focus absolutely nailed, the dim background nebulosity shows well and the background is clean. You've stretched the image with surgical precision for the amount of exposure time you had. The highlights in the bubble are so easy to blow out and you've controlled this perfectly. More to the point, just sitting back and taking the image in, it just looks right. TOP JOB!!

You are spot on about using the minimum exposure time possible. This gives you the maximum number of subs for sigma reject as well as reducing number of reject images. The trick is to work out what is the minimum exposure and I think this CCDware calculator is the best I've come across Welcome to CCDWare

The trouble is that on a clear night here, using a 7nm Ha filter and a fairly low read noise camera my minimum recommended exposure can be up to 45 minutes! Last night with a full moon and a load of high cloud it was down to less than 2 mins, time to give up! It's a very useful tool, sometimes minimum exposures are surprisingly short and this is well worth knowing when doing colour subs and trying to get the best star colour possible.

[russ]

That is a quality image. Amazing detail.

[Darth Takahashi]

You've stretched the image with surgical precision for the amount of exposure time you had. The highlights in the bubble are so easy to blow out and you've controlled this perfectly. More to the point, just sitting back and taking the image in, it just looks right. TOP JOB!!.

Thank Martin that's praise indeed come from yourself; however, I have to credit RobH for the stretching process. He taught me a very nice trick in PhotoShop where you can control click on the areas of the image that you want to stretch and it works a treat...

This is definitely one of the reason to attend SLG6; meeting people like yourself and picking up new techniques etc...sharing the hobby and learning.

I'll definitely take a look at the CCDWare program you suggested.

Tonight's looking good, fingers crossed

[dc509]

Great image - like you , Ha images have a great quality about them - love it