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RyanJones
24-06-2018, 12:21 AM
Finally a pic I can be happy with.

Nexstar 4se
No filters
Unmodified DSLR
About 20 west of Melbourne

raymo
24-06-2018, 12:38 AM
Hi Ryan, welcome to the forum. When posting images for comment and/or
critiquing, can you put the acquisition details, such as exposure[sub] length,
how many subs if more than a single frame, ISO etc:
Sorry to rain on your parade, but I can barely make out the object you
have imaged, and also it looks as though the focus is off. How did you focus? do you have LiveView, or use another method?
raymo

RyanJones
24-06-2018, 10:12 AM
Hi Raymo

Sorry for the lack of detail. I'm very new to this

60 x 20sec exposures
10 darks
ISO 400

I'm still trying to work out the best setup to use to get reasonable photos. My scope is polar aligned but has jerky tracking in exposures over 30s or so. That's why I used lots of short ones.

Re: focus. I use a bahtinov mask. I'm assuming the out of focus is more to do with the way I post-processed it. The Stars were quite a bit sharper before but were only stars.

Re: The " object " . It's of the carina nebula. Not of any specific object within or the complete nebula. It's the first pics I've taken though that don't look terrible..... I shall get back to the drawing board ......

xelasnave
24-06-2018, 11:23 AM
Welcome Ryan.
You have done well to capture something and we welcome you sharing your effort.
Keep them coming.
Alex

Imme
24-06-2018, 11:57 AM
Well done Ryan.... Still remember my first pic that i could actually see something.

Great effort.... It's a steep learning curve but well worth it. It was only 12 months since i started. Great results won't be far away!

Anth10
24-06-2018, 12:36 PM
Ryan,
In Melbourne the Light pollution is always going to be your worst enemy when doing astrophotography (apart from the clouds needless to say really).
Without a Ha sensitive chip you will struggle to get any nebulosity coming through in your shots. I found this too when I first began.
You may want to consider full spectrum modifying your Canon dslr. It will help you get some colour coming through which will amaze you. But you can still manage to get around this by increasing your ISO to say 1600 and you will for now see a big difference.

All the while continue to have a go and good luck!

Anth

raymo
24-06-2018, 01:10 PM
O.K. Firstly, I disagree with Anthony; I suggest you get your procedure
working well, and explore the limits of your unmodded camera before
laying out hundreds of dollars on a modded camera, because if you get
hooked into astrophotography, you might well decide to go for a much more sensitive dedicated astro camera.
What is the focal length of your scope, and what mount do you have?
You will obviously get star trailing if your PA is not good enough, but should never get any jerkiness. As an example a 1000mm focal length scope at
prime focus, well polar aligned, should give all good subs at 30 secs, and
an acceptable percentage of useable subs at 45 secs, and a occasional
subs at 60secs or even a bit longer.
I wouldn't waste time on darks until you are producing some reasonable
images, and as Anthony said go out to around 1600 ISO. which is the so
called sweet spot for many DSLRs. I light pollution filter can help, but then
you will have the job of removing the colour cast introduced by the filter.
Further to the modded camera, it is only the fainter red nebulosity that
doesn't show well in an unmodded camera, all the other colours are unaffected.
Longer subs can overcome that to a degree. I have managed without a modded camera for many years.
raymo

RyanJones
24-06-2018, 02:21 PM
Thank you all for your feed back. I never knew AP was so complex, but despite the hours of subs I've thrown out getting to just this pic, I'm loving the challenge.

Thanks again for all your feedback :)

Robmozzy
24-06-2018, 03:13 PM
I think that you need more short subs rather than longer subs as the smaller Celestron scopes are not built for imaging and are extremely under mounted. Hence any jerkiness. They track well enough but you can't really be anywhere near the mount when it is imaging as even vibration from walking past will affect it. Even the click of the camera shutter will effect an under mounted scope.

cometcatcher
24-06-2018, 04:09 PM
Hi Ryan. I'll add my 2c worth. The 4se is not really a good photo rig at f13 and only 4" aperture. It will take a lot of skill to coax an image of anything faint. I think your focus is fine considering the scope. I think your best targets for that scope are open star clusters, moon and planets. It will struggle with galaxies, globulars and nebula. Good targets are the jewel box, m6, m7, ngc3532, the pearl cluster, I forget the designation. Sprinter cluster. Etc.

raymo
24-06-2018, 04:33 PM
I was just about to post when Kevin's appeared. I had somehow missed the
scope in your signature. I'd like to add brighter planetary nebulae to
Kevin's list, as they require the longer focal length that your scope has.
M57[Ring Nebula], NGC 3918,[very small, but easy to find with your GoTo mount], and M27, spring to mind.
raymo

RyanJones
24-06-2018, 04:37 PM
Hi Rob,

What you have said is exactly what I've been finding in my limited time trying so it's good to hear you confirming that for me. I've tried longer subs and on top of the large number of unusable subs even the good ones don't seem to help me as much as lots of short ones have. At this point I'm going to try and get a the best out of what I have being fully aware that I will reach the limit and have to invest in better equipment. Thank you for you feed back :)

Hi Kevin,

Every 2c is welcome :)
I will try some of the objects you've listed and see what results I can achieve. I did take some a few nights ago of M4, again around 60 usable subs @ 20 sec and I was really happy with the result apart from the fact I was in a rush watching the clouds coming over and hadn't framed it very well and cut off the top half. I'll definitely give some of the objects you've listed a go :thumbsup: thank you :)

RyanJones
24-06-2018, 04:39 PM
Thank you Raymo,

I'll try the objects you've listed also :)

Robmozzy
24-06-2018, 05:03 PM
You have the right idea Ryan. Grow slow mate. See what you set up is able to do and go from there. Most of us will image for the rest of our lives so no rush. You may find your scope with a cheap little web cam will do the moon and planetary images well.

RyanJones
24-06-2018, 08:48 PM
Rob,

Funny you should say that about the moon and planets. Before buying a DSLR, I actually modified an old Sony cybershot point and shoot CCD to fit on a Plossl lense that came with the scope. To date it has given me the best pics of the moon, Jupiter and Saturn.