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xelasnave
21-06-2022, 11:56 AM
OK I admit the title is click bait but I had to start somewhere to tell of my latest adventures with developing the RASA RIG.

Read on if you have little to do as there is not much meat in this sandwich.

So the best night so far, no where near perfect but you could see stars...the clouds came in for ten minutes but faded into more mist..not ideal but I could still see stars..go for it.

So testing things ...finally got the focuser mask to work..it needs a very bright star otherwise only produces blobs..however when it works it is rather decent as I got lower readings on Sharpcaps graph than I have ever seen. It is unusual and I will post what it looks like later I hope.

So that is a huge step forward but it will be limited by the need for a very bright star..looks pretty ..

So tested performance using 8 second subs and I am impressed. I will post that result if I have time also..I would like comments as to focus mainly...I thought it was good but that was last night so..

I had done a factory reset a while back and had not done a new star alignment...well I dont know what went wrong but that did not work and after a second go with out success decided to return to that another time and not waste imaging time...finding stuff is not a problem but wasting time is a trap that I avoid. Just use the finder scope and get imaging before the clouds appear again.

So I settled on the Lobster Nebula and only then noticed the mount had stopped tracking...re start..still no tracking:mad2:...mmm stay calm go thru the proceedure;)..power ..slews OK but to be sure go out in the dark fill the genny and start it so it simply is not an issue and make it back without falling:rolleyes:...done even with no torch:screwy:..then check plugs leads connections and make sure I was holding my mouth right:P...

finally it seemed the plug on my relatively new power box was rather loose:confused2:...without realising I could have borrowed the power box from the EQ6 right alongside I rummaged around and found a suitable plug:lol:..but it needed 12 vlts..mmm I will use this 7 amp battery and connect it to the charger..I love simplicity;). And was rewarded by achieving tracking...by now I had moved the mount all over the place as included in my search was releasing and refastening the RA clutch..and the lights are on in the observatory so I now can not.. see the sky and not sure where the scope is pointing....I was busy trying to keep the charger connected and hold the power leads in place ..it was a patch work of mess and disorder..so I had more or less given up for the night and ready to close the show but I started a little tour just looking at what appeared on screen now that things were holding together ..oh thats a nice blob..mmm just look at all those stars..still no idea where I was and the lights were still on the only thing I could see was the bright screen..but all I was now doing was checking on the tracking really...then I noticed a faint blob and thought that looks like a galaxy...turned up the gain and yes definitely could be maybe..heck I need to know so I started taking 30 second exposures and stacked a few..I am sure I can see some spiral arms..maybe..so I took more 80 all up and stacked them..well I think it could be M..? but it just does not seem right...it sortta looks like its picture but the stars dont seem to co incide???

I have got to the point where I honestly dont know..well that was last night at 12 or 1 am but without plate solving what do you think it is?

also I experimented with a small sensor size so this is a non cropped image.
it is ruff but I will have a real go tonight maybe as I left dec untouched so a cruise in RA should find it again..I have not looked today so no idea..and keeping it that way:D:P

If it is not what I think it is I would not be surprised but given not knowing in the least where the scope was pointing I feels like a new discovery so I am indulging that game:D

alex

multiweb
21-06-2022, 12:01 PM
That looks like NGC6744 in Pavo. Good shot. :thumbsup:
PS: You need to mirror it.

xelasnave
21-06-2022, 12:02 PM
Here is how the mask treats a star.
Alex

xelasnave
21-06-2022, 12:09 PM
No I was in Tabulam.
Thanks Marc:thumbsup:. I confess I though it was M83 and what was funny was how I could convince myself it was by allowing for a poor quality image ... The missing stars was a concern at first but having read recently about all the missing stars even that did not prove it was not M83:D...I just found it novel to be lost in space:lol:

Alex

Startrek
21-06-2022, 12:27 PM
Alex,
Nice image !!
Well done !!
Definitely Pavo Galaxy NGC 6744
It’s more elongated than M83 , M83 is almost circular, hence its name Southern Pinwheel
For identification , Goto and framing …..
I have all my images in a file on my iPhone going back 3 years , because I don’t plate solve , I use EQMOD and sync based alignment, I use Stellarium to select and Goto target and for identification and framing , I use my iPhone images and their Star asterisms to centre and frame up the object, seems antiquated but works , it doesn’t take that long at all

Glad to see you have sorted focusing and taking images with that big beast

Cheers
Martin

Dave882
21-06-2022, 12:31 PM
Yep that’s ngc6744. If you ever have an unknown fov / object you can upload it to nova.astronomy.com and it will auto platesolves it for you. I just did it with you image and the results are attached.

Regarding the mask- that looks like the refraction pattern you get from a tri-bahtinov mask. It’s used for focus AND collimation. I’ve never used one so can’t really give much advice on how to use it but I understand that it needs to be aligned with the collimation screws and everything is made symmetrical (both the groups of 3 spikes by adjusting focus and also the individual spikes by turning the collimation screws). I think… :shrug:

xelasnave
21-06-2022, 01:12 PM
Result of test using 8 seconds at 350 gain only 32 frames...and focused using mask.
First image uncropped but will suffer from weight loss.
the second is a cropped section that may show how the large one presents.

that is 4.2 minutes exposure:eyepop:

no doubt I could have used less gain ....is it fast ...yes it certainly seems to be... I may try doing a narrow band in less than an hour for a bit of fun and to fit in the time frame usually available;)
alex

xelasnave
21-06-2022, 01:28 PM
Thanks Martin I just found it so funny having no idea where I was...
All going well I will get more data tonight...selecting a small frame has me wondering if I should continue that way...also still not fits..maybe another hour of colour if the clouds permit. But hey I now have two new T shirts ..so watch this space..and I feel flats with this things may be hair pulling...so prepared for the worst I cant lose.
I wonder if I will ever get this show on the road??? but I must be strange as I got such a kick just working out why the mount was not tracking...and happy to find the problem because I was going to pull the mount down and do whatever it took...which would have been a lot..like block and tackle to get the scope off for a start...

alex

xelasnave
21-06-2022, 01:41 PM
Thanks for your kind help.

I dont know if the mask will get correct attention to be honest.

This scope is such a pain to use.. you need to remove the dew shield to change a filter and putting the focuser mask in place you need to jiggle it around the camera leads even after you disconnect the camera...so I look forward to computer control at some point in the future.

But I love the exta nonsense as it builds my character and gives me something to discuss with the check out girls at the supermarket..
just cant wait to tell them the latest:P

thanks again
alex

gb44
21-06-2022, 07:19 PM
Alex
Rather than using a bahtinov/mask you should look at SharpCap Pro where you select the focus aid to measure multi star FWHM measurement. You can observe a graphical representation of the focus iterations. It seems pretty good to me. Select a ROI with say 10-20 stars, play around with gain/exposure.
Another thing the program can do is record sensor analysis data which you then use to determine the ideal number of exposures at an ideal gain. You would be able to set the exposure length and it would give a gain and exposures number I think.
Both functions arent in the free demo but its a cheap enuf program. I dont know if you use it sorry.

GlennB

xelasnave
21-06-2022, 09:03 PM
Thank you very much for that advice Glenn.I have only recently obtained the full version of Sharpcap so your advice is most timely:thumbsup:.

I am trying to go as short as possible for exposure times hopefully on the basis that the images will be sharper. I was very surprised the results above at 8 seconds and 4.2 minutes...heck hopefully I can knock out images at the rate of one per hour:D I have not done a sensor analysis but it is on my list of things to look into.

I am banging away now on this galaxy and have stayed with the small frame ( sensor area) mainly because they stack fast :D I have over 200 lum and starting on some green right now...I lost over 100 because of mist..it is so hard to see visually but I can tell as the image looks a little crook..there are various issues that need to be addressed when you look closely at my stars...I gave up on the mask tonight as there was not a single star in my frame that made the thing work..just blobs...I will try your suggestion when I change filters but I seem to get close just eyeballing it...anyways not too worried mainly because of the mist it is hard to get serious... but just doing stuff is helping me sort things out ..but so damn wet even my jacket is now wet...but I am really enjoying playing with this galaxy..I stack what I have and process that stack and then process again with the images that came in while I was processing...and using the experience to try little things out in Startools...and each one is marginally better than the last and it is fun watching detail appear in the next image

Thanks again I very much appreciate you taking your time to help me.

alex

xelasnave
21-06-2022, 09:36 PM
playing around while gathering more data

xelasnave
22-06-2022, 11:56 AM
Well lots of fun but not too flash...

alex

JA
22-06-2022, 01:26 PM
I'm not sure that I agree, I think it's good:thumbsup: - what you've put up is a considerable crop of your field of view and of a relatively dim object, so there's always going to be some quibbles.

Best
JA

xelasnave
22-06-2022, 01:32 PM
Thank you JA you are very kind and I appreciated your encouraging words.

Alex

Dave882
22-06-2022, 01:45 PM
Very nice Alex. That’s a really tough dim target but you’ve still managed to expose even the outer arms leading down to ngc6744A. Well done!

AstroViking
22-06-2022, 03:40 PM
Those last two are lovely images, Alex.


Personally speaking, I think a colour palette somewhere between the two would look great. To my eyes, the left image has too much orange, whilst the right one is slightly too blue. As always, it's in the eye of the person driving the mouse to decide what is right or wrong.


Cheers,
V

xelasnave
22-06-2022, 05:20 PM
Thanks David and thanks Steve...

AND although far from perfect this came from not letting disaster ruin things..as I said earlier I ran into mount problems ..with power and also with star alignment for whatever reason and having fixed the tracking found it was too late and too wet to be serious and so I just took an on screen tour and found this galaxy and took 50 subs to reveal it's arms...and the following night got more data even though it was just too wet...and in the process have learnt that I can image something faint using 30 seconds and high gain..and I really believe if you used correct gain and correct exposure times in this wet you would not get a result....But it really was fun not knowing what it was etc.

And Steve you mention colour...I am colour blind and if it does not cry out green and purple I am very happy...and both images were the result of bringing together two images so I am a victim, of that ...

Thanks again.
Thanks again

Alex.