Catanonia

Started over with your instructions and image below is at the stage of focuser alignment (it was way off)

Getting to grips with it now.

Next to move on to the secondary and then the primary.

Slowly slowly and learning the ropes with the scope and Ocal (yes the documentation of Ocal is pants)

Thanks @powerlord

8 minutes ago, powerlord said:

So you've got red on focus tube, blue on secondary edge, and green on ? was green centred on edge of primary until you adjusted to put camera on centre ?

And just checking - are you using the focus on the ocal ? that can really help get the circles precisely over the relevant bit.

I'm re-writing the Ocal Manual just now for Ocal, so interested in anything you found difficult/tricky.

stu

Not sure what I am doing as 1st time

I basically put the red circle where it is as a reference and to fine center the purple cross hairs.

I then manually expanded and contracted the green circle to check it was centered on all round edges I could see.

To do this I tweaked the secondary as it was not centered, then made fine adjustments to the primary.

The blue line was just on screen for another reference point whilst tweaking

Not touched the focuser centering at this stage.

I used a self centering adapter for the camera

Truth will come on 1st light with a star defocus test

I have just taken delivery of a 10inch open truss RC scope along with an OCAL electronic collimator.

Not surprisingly, out of the box the scope needed re-collimating. It was close but not close enough

• Does this look collimated to your eyes ? 
• Good enough for F8 or F5.3 ?

Thanks

@The Lazy Astronomer Here are the results.

• 1st image is 2 hours in 1min subs 2xbin
• 2nd image is 1 hour in 10min subs 2xbin

Processing is pretty much the same in both images.

What you can see in the 10min sub version is a ring flare from one of the bright stars (The star in the top right of the 1st image) that the 10min sub picked up and becomes more visible with stacking.

I had to bin 2x 10min subs due to excessive satellites and plane trails, something that 10min subs will greatly increase.

Interesting experiment from a Bortle 6 sky, certainly got more detail, but combined with more hassle in each sub.

Nice work. 

It is surprising how faint this nebula is. What sub lengths were you using ?

I am currently working on a 4 pane mosaic of this at F2 with the Rasa8 and the lEnhance filter so this is a good reference for me.

Got another 8 x 10min subs to add to this tomorrow

4 minutes ago, gorann said:

Did a negative:This SNR has eyes, a nose, mouth, cheek, and neck!

 

Can you post the jnow coordinates. Might point my Rasa8 at it tonight for a 20min sub for fun.

Sweet buddy, very unusual to get something like this and something we all aspire to when pointing skywards. What if we discover something

Put more hours into it and send it in as a APOD or send it to a magazine. It would make a great story.

Well in 10mins, this single 10min sub from a Rasa8

7 minutes ago, clarkpm4242 said:

Nice.

@Catanonia what method/kit do you use to generate flat frames on your RASA?

Many thanks

Paul

White teeshirt drapped over the dew shield scope end and pointed to sky next morning under the same camera cooling conditions.

ASI Air Pro auto calculates the exposure needed for flats based on the settings in place.

26 minutes ago, Elp said:

That's nuts, I'd be happy with that and you don't even have to stack and can do more targets in a night.

I am going to continue the experiment tonight and add another 3 or 4 10min subs and see what I get.

I can already tell (and expected) that the single 10m sub gave more detail than my combined 1min stacks (x10).

Updated the thread with more details and a quick process of the single sub

19 minutes ago, alan potts said:

I was told it was not possible to bin OSC cameras, I have the 071 and thought to do the same thing, but after being told never did. Very good capture for only 10 minutes though.

Alan.

Yes possible and follows same processes as you would with normal images.

Wow interesting.

I have often wondered if the RASA 8 @F2 and ZWO 2600MC Pro combo could produce a good image with a single sub. After all the Hubble deep image was a single sub and why can't I try it

And what would it be like in good seeing (2.1) in Bortle 6 skies, would it flood the pixels

For for giggles, last night I pointed the RASA at the Horsehead Nebula and Flame and took a single 10 minute guided sub to see what would happen.

I was lucky that no Satellites / Starlinks came through the image, but was very impressed.

Below is the final processed image from a single 10min sub  (flat, dark, DBE, and other quick processing) compared to raw (jpg) sub that the ASI Air Pro presented after the 10 mins

Image

• Single 10min sub at 2xbin with RASA 8, ZWO 2600MC Pro and EQ8-R
• Optilong lEnhance filter
• Processed in PixInsight (Flat, Dark, Bias, DBE, Colour and stretches)

So is this practical.

Well 10 mins guiding at 400mm is not an issue on the EQ8-R, but the chances of satellites is high. Perhaps 3 or 4 10min subs would work (to remove any satellites)

But overall, extremely impressed with the result for a single sub.

Deionised water and lots of cotton wool.

Take it easy and not issues

On 28/02/2022 at 13:13, adyj1 said:

@Catanonia, did you work this out?

Badly as the 7nm filter is not good enough for F2 with a RASA8.

I need a high speed narrow band filter to work with the highly angled light from F2

I ended up with HA data that was about 1/10th of what I would have expected.

35 minutes ago, michael8554 said:

The clue's in the description:

M48X0.75 

0.75 being the spec of M42 and M48 extenders.

Back in the days of film cameras there were many lenses with M42 x 1 threads,  which often caused mating problems.

Strictly speaking M42x0.75 is T2,  M48 isn't T2.

Michael

The title says M48 x0.75 but the descriptions talk about T2 hence the punt knowing if they turned out to be T2 due to cut and paste by the seller I could send them back under Amazon

I love this thread. Full of goodness and support and why I love this hobby.

15 minutes ago, Clarkey said:

Nice image and better than my one attempt so far. (A few subs then canned the idea)

It's always been one I had on my 'to do' list, but I have always left it due to my light pollution problem. I am in Bortle 6, but imaging to the south is the worst area of sky for me. One for a dark sky night.

Feel ya pain dude, I HATE and LOVE this target, a real tester of kit, location and skies

M78 in Orion has always been my nemesis as it is such a difficult target from my Bortle 6 back yard.

Due to its position, I can only get about 4 hours on it per night.

About 6 years ago I took the 1st image on a SkyWatcher MN190 and it was about 10 hours mono LRGB combination.

Fast forward to last night and 2 hours integration on ZWO 2600 MC Pro OSC and RASA8 in 5min subs I got the following.

Heavily cropped as the scope is only 400mm, but an improvement, but still seriously lacking.

Still my nemesis and can only hope my new 10 inch RC open truss will do it more justice when it arrives.

As a prime member of Amazon, I always go there by default.

Well I was struggling to find M48 extension tubes to give me loads of options and surprise surprise, these from Amazon arrived and they are excellent.

Took a punt as the title says M48 and the description says T2, but with zero shipping costs and easy return, I took the punt.

They arrived today and are absolutely perfect.

https://www.amazon.co.uk/gp/product/B09P4XLMZK/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

And a hell of a lot less than I could find elsewhere.

Thanks all.

This target is perfect for the 400mm of the rasa

19 minutes ago, assouptro said:

Wow! 

.....

Bryan

Thanks 

The main reason I bought the Rasa, take full advantage of those gaps in the clouds. A couple of hours to get an image that previously would have taken 10+

Back into the hobby after 10 years and it has been a fun time.

Many painful hours watching the met office and wondering why the crap I got back into this hobby.

But when I look back on it, yes well worth it.

New scope arriving soon  (RC 10inch open truss) and exciting times are ahead

Hope you enjoy what is possible in 6 months in the UK