The evolution of a astro-photographer - gaining skills!

[g__day (Matthew)]

I was curious how people evolve their Astro imaging post image capture capabilities. If I examine my own journey over the last 8 months it has been a bit of an uncharted course forward. The gaining of whatever proficiency achieved could be summarised in stages as:

1. Attach a DSLR camera to an OTA, focus and take a manual shot
2. Cable a remote bulb control and do a controlled exposure exceeding 30 seconds (DSLR Shutter or MaximDL)
3. Play with exposure duration and ISO settings (settled on ISO 800)
4 .Migrate from jpg to RAW shots
5. Trial different DSLR lighting (colour balance) modes
6. Learn auto guiding and try and hone it (PHD and then MaximDL)
7. Reducing periodic error (PEMPro)
8. Improving pointing (Maxpoint)
9. Learning drift alignment and improving polar alignment (PEMPro)
10. Learning collimation and get the optics sorted (CCDInspector)
11. Trying to nail focus as finely as possible (MaximDL)
12. Learn histogram streching (Photoshop CS2 Levels and Curves)
13. Learn about stacking, dark frames, bias and flat frames (Deepskystacker)
14. Experiment with filters like Gaussian Blur (Photoshop CS2)
15. Starting to care about colour correction (MaximDL)
16. Explore the power of Photoshop CS2 layers to target more advanced image processing (Duplicating layers, Clone Stamping the Nebulae, Gaussian Blurring at high 90 pixel radius the field and subtracting this blurred image to remove vignetting)
17. Adding light pollution filters to make nebulae stand out a bit better (next week hopefully)!

As I stated earlier – it’s been a random walk – with much time spent try to track down and eliminate sources of error in pointing and guiding before I get really serious in honing my image processing skills.

I’ve finally cottoned on to how much effort and skill has to go into image processing. It’s like the mechanical set up has improved substantially, now I’m at a new base camp where image processing skill required to be improved substantially. Once this is gained I’ll likely get a better Astro-imaging CCD and have to learn about Ha and Luminance processing etc.

I wonder how folk have planned and optimised their journey through the black art of astrophotography and what other tips and tricks can be learnt to speed the journey towards serious Astro-imaging skills?

[Tandum (Robin)]

Matt, How are you using maxim to focus? Are you just using the numbers on the big focus display or are you automatted? If you're using the numbers, are you focusing on a nearby star then moving to the object?

I've wondered how maxim can drive a robofocus or similar when images are only coming out every 5 minutes or more.

I kicked off with my meade DSI, it was fine for planets, but useless for deep space. My tracking wasn't anywhere near good enough to get an image that wasn't blurred. Now I have a dedicated guide camera and scope I'll give the DSI another go, when it stops raining

I bought light pollution filters to get longer exposure times and it has worked. I can get double the time now before hitting sky fog.

I just bought Photoshop for Astrophotographers by Jerry Lodriguss which is full of info on how to do it but not much info on when to do it

[g__day (Matthew)]

Robin,

I turn off the DSI and run the Canon DSLR 400D. Auto-focus seems to miss the mark (I use a Meade Motorfocuser controller by a JMI USB under ASCOM). So instead I take shots and look at the FWHM on a bright star with 1-2 second shots until things look focused.

The C9.25 being carbon fibre keeps focus amazingly well!

I bought Rod Wodaski's Zone System for Astrophotography (half way through it), or otherwise pic tips up from folk here!

[Tandum (Robin)]

Doesn't the 400D do live view? I've been using live view on a nearby star to focus and then slew back to the object and take a few longish shots to frame it. I've found a bright star is no good to focus on, a star that just shows in live view is best.

I've been looking at robofocus, they make one for the vixen, but it's pretty expensive (about $500) plus I have a 7:1 knob on the scope as it is and that works just fine so I can't justify the expense at the moment. Maybe when I want to shoot for several hours at a time.

Photoshop is the problem for me, I have access to the techniques but knowing when it's best to use them is the problem. That's just experience I suppose.

[rally]

Matt,

Thanks for sharing - its a very useful personal experience milestone map for others to consider.

I see you've excluded some of the pitfalls like : communications issues, software setups and configurations, other installation issues like adapters, wiring, etc etc !

Cheers

Rally

[Tandum (Robin)]

I've experienced none of the pitfalls mentioned by rally but I do computers for a living so I'm probably oblivious to these things and just glaze over them as a matter of fact.

[g__day (Matthew)]

Yes - the wiring had challenges - I think the auto guider port for a Vixen was hard to wire and the Meade DSI sometimes blue screen of death Windows when the cable wobbles and mirror flop on the SCT caused alignment issues for quite some time etc...

But this was a thread on gaining the image processing experience more than the mechanical point and track skills.

And no the 400D is Digic II so no live view...

But with a bit of photoshop processing with just one shot of the Eagle 600 secs - using layers and subtracting clone stamp altered Gaussian copies to remove vignetting, then simple levels and curves an a final soft Gaussian Blur and Unsharp Mask you get the following - from an shot guiding at a 10 second interval (couldn't find a guide star - it needed 2-3 second guiding I'd guess) , with a novice at the hands of Photoshop really:

Original (shrunk) and processed shot (also shrunk) for comparison:

PS

I goofed the stars - I should have selected them, inversed selection and then Gaussian Blurred only the Nebulae using a 2 pixel radiuss. By including the stars in the Gaussian Blur I accidentally softened quite reasonable stars - my whoopsie!

[Tandum (Robin)]

Get your CLS filter plugged in and you'll double your exposure time. That's a cool image but the bloody skyglow. I had the same problem here.

You should post images in the deep space forums so experts can give you advise.

Check out these 2. One is post processed by me and the other is done by an expert ... Which is which ?

It's obvious without clicking on them.

Chucked in the raw pic as well, 10minute subs.