1st light(s)

[Bassnut (Fred)]

1st lights with my RCOS 10" RC at f6 and Paramount ME.

Helix Nebula in Ha 15 off 20min subs, and Tarantula Nebula in Ha 22 off 20min subs, external guiding.

http://fredsastro.googlepages.com/home

I was supprised at how small the stars were compared to the LX, and I have not been able to do 20min subs this tight before. The OTA and stability of the ME together seemed to have made the difference.

These images have next to no processing, any extra just made it worse, im not used to this, a big shock . Only some light deconvolute, and by accident I loaded the fits into PS with fits liberator with a log stretch, in this case much better than linear, Im mad I hadent tried this before, saves much curves work in PS and much smoother.

I dont know if the RC is capable of better than this, they seem a bit soft, but I havent got the magic "backfocus distance" number yet (its slightly different with every RC scope), I just tried a random guess, I could be way out, and I dont know if collimation is OK (CCD inspector is the next purchase, it never ends). The spacing between scope and cam has to be withing a few mm for max performance, the LX was relatively sooo convienient. Setting up an RC is quite an experience, it comes (with the TCC, telescope command center) with automatic fan, 3 dew heater and a temp compensating focus controllers that all need calibration. But once its set, its all on and go!.

The $'s dont warrent excuses really, but the learning curve is steep .

Cheers

[duncan]

Oh Boy you sure nailed these two! Absolutely amazing detail.

[Ric]

Hi Fred, great first images.

The Tarantula is fascinating, I don't think I have ever seen an image of it with that amount of fine detail. It's more like the spiders web rather than the spider.

Cheers

[jase (Jason)]

Ooohhhh Yeeaaaahhhh. That’s some kick’n data right there Sir. Fredrick. That is *the stuff*. If I’m not mistaken, that would be delivering the 1.2 arcsec/pixel sweet spot with the ST8. Stars are certainly tight on the RC’s. You only need to look at the optical spot diagrams to realise this. For our amusement (ermm benefit ), it would be good if you had the time to frame these same objects with your 10” LX200R to see if Meade eats their words regarding their “advanced ritchie chretien” design – ok enough flaming for now.

I think you might get it sharper once you know the BFD (mystical number indeed). The RC optical design is rather tight. Though I don’t know if your upscale data "trickery" processing is what gives that perception of softness. The Paramount ME is looking good to atleast 20min subs. Try 6 x 30 min subs to see how you go there. Should be capable of at least 30min I’d say.

So stop teasing us with just Ha data. Get back to work and finish off the SII and OIII data acquisition. Processing good RC data is a real treat.

*EDIT* - I just check out your equipment page. Whhhooaa. That is some seriously sexy kit once it comes together. Drool factor 9/10. ME still looks like it dwarfs the 10" OTA. I suspect the carbon truss RC would be slightly larger.

Cheers

[Bassnut (Fred)]

Thanks Ric, yeah, there aint that many deep pics of Tarantula around, beein in the wrong hemisphere, but I intend to go deeper yet.

Jase, so many emotes, glad your green with envy hehe, youll get there eventually. Yep, right in the arc/secs sweet spot. Im struggling with external guide experimentation useing the ST80, even with steel square section locking the guide cam to the guide scope clamps im about to give up (you can see it in the equip pic). 20min exposures were OK, 30mins acceptable, but 60 exposures showed up differential flex someink cronic. Of course internal guiding would allow unlimited exposures.

Once I colimate and get the BFD right, then ill see where the money went ;-). The upscaling just reduced pixelation, it didnt cause the softness. I just wasnt game to deconvolute or sharpen further due to the drubbing I would get from your goodself with the inevitable artifacts.

Ive got SII and OIII data, but that does involves processing, stay tuned.

The 10" RC is bigger than the 12"LX, and much longer. And the venerable G11 looks positively overloaded compared to the ME. The RC/Me combo looks so wanky yeah, hehe (sorry about the messy wiring, itll all be thru the mount shortly, man there are SO many wires).

Cheers

[jase (Jason)]

What’s that noise Fred… Did you hear the Dichroic Beam Splitter calling?

Seriously, it will be the answer to your guiding woes assuming you intend to go longer than 30mins for subs. I can’t imagine why you’d do that now anyway. Your ST8 has an NABG chip so unless you’re using some really narrowband pass emission line filters (like the Custom Scientific 3nm Ha for example) you are going to get blooming within 15-20 mins, right? The benefits in going deep really on work with ABG chips as they bleed photons as the pixel wells begin getting full (typically around 80% mark). Like most CCD cameras, this can be tuned. I know the STL series has a setting you adjust inside the camera to alter the depth, but really I don’t see any true benefits of such tweaks. Of course if you are interested in doing scientific work (say photometry), stay clear of the ABG chips. The bleeding of photos/controlling of pixel well depths can alter the true reading of star values/measurements.

[Garyh]

Fred Fred Fred,
very nice!! as mentioned so much Ha detail showing there!!
I just had another look at your new gear and the wife has come back with a bib!!!
Your soo mean... making me dribble so much!!!
Seriously nice stuff!
I should expect some real croppers out of you in your following posts
cheers Gary...

[jjjnettie (Jeanette)]

Fred,
Your images are superb!

[richardo (Rich)]

Man, you'se cooking now Fred....
What a setup you lucky dog!!!
And some excellent first light images...
Love 'em all especially the amount of extended neb to your Helix.

I guess your using a motor focus???, if not, you should be.
Make a heap of difference to how tight you'll get your stars.

Top shelve and your in for a truck load of fun with this
lovely gear...
Congrats

All the best
Rich

[Dr Nick (Nick)]

Stunning!