M27 Dumbbell Nebula from Rother Valley 9.7.2010

[Mac]

its a lot better, the stars are not bloated and you can start to see the colours in the stars as well,

You are well on you way now, its just practice as you said. and patience.

Mac.

[Rocket Pooch]

slight guiding issues

Hi Chris, could you elaborate as I thought the guiding was OK. 

Thanks
Carole

The stars are not quite round.

[Rocket Pooch]

I will given time, but I don't want to be excluded from doing these sort of objects. 
I think things will get better when I can use the ETX125 OTA for this sort of stuff and when my mount is behaving itself. 

Err, I think its going to get worse with the ETX125, for a start its a slow scope, secondly the imaging circle of the scope is tiny, and you will be well over the limit of the mount at 1.25 meters FL. 

[Carole]

Oh dear, so what's the solution?

[Rocket Pooch]

AP900 and a Tak, or maybe an EQ6 and an ED120 with a FF. Or a flat field astrograph, something like that.

Personally I stick with the wide field stuff till you get the basics mastered.

[Carole]

Personally I stick with the wide field stuff till you get the basics mastered.

Yes, sounds sensible.  The ETX was really for doing planetary anyway.

Would my current set up be improved by getting a barlow then?
(All my current Barlows/powermate are 1.25" unfortunately). 
I've got a 2" to 1.25" T piece but could not get focus last time I tried it with a barlow and DSLR. 

Carole

[Rocket Pooch]

Carol,

I think you have reinforced my comments about getting the basics right 1st.  

Your jumping ahead of yourself and all you will end up doing is asking us sooooo many questions it will prove frustrating for us here.

I'd suggest you get to do some research on the web and ask the questions there first, there are 1,000's of articles on imaging and being in the scientific community most resources are free.  

The biggest issue with astro imaging you need to get your head around is its a technical subject and when you start its like going to school, you need to understand your ABC's first then move onto spelling reading etc.  

To make a suggestion search on the web for focual lengths v's F no's, if you look around the web for Imaging Circles and Field Flattness this will help explain some issues around exposure and field of view.  I don't think we need to explain what the effect of a barlow is and its affect on the speed of the scope and coverage on the CCD.  Just type it into google.  Actually I just did and this is what I got, http://www.astrosurf.com/luxorion/report-formulae.htm

I think your making good progress, but we have all been where you are at one point or the other, and we have toughed it out and found our own path to imaging.  There is no one answer to all questions for imaging, you can only investigate and decide what is right for you.  If there was one answer we would all have the same kit.

Chris

[MarkS]

AP900 and a Tak, or maybe an EQ6 and an ED120 with a FF. Or a flat field astrograph, something like that.

I think the AP900 might be a bit heavy for Carole to take to DSC ...

[Rocket Pooch]

Don't be silly, she would ask someone else how to set it up.

[mickw]

You just made beer come out of my nose...........................

[MarkS]

Carole,

The re-work certainly looks better but because you have processed the nebula and the background separately you haven't managed to shrink the "blobby" stars in the nebula area itself.

Try loading up the TIFF file in IRIS and use colour stretching from the "View" menu.  A stretch coefficient in the range 0.0010 and 0.0050 should do the trick.   Remember to set the black level in a blank piece of background sky first.  I use this for alnost all my images and highly recommend it for its simplicity and good results.

Mark

[Carole]

you haven't managed to shrink the "blobby" stars in the nebula area itself.

Yes I realised this but wasn't sure what to do about it.

Will see if I can manage to do it in Iris.

Carole

[Mac]

just out of curiosity how many different pieces of software do you use?

In fact I'm going to start this as another question.