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LewisM
07-10-2012, 07:44 PM
Just 30 stacked subs (ISO 1250 / 20", 6 each darks, flats and bias), straight out of DSS with absolutely NO processing other to convert it to .png format. Vixen VC200L with f/6.3 focal reducer, unmodified Canon 5DMkII, no cooling (the CMOS temp was running between 28° and a whopping 38°!!!). Canon internal noise reduction on. NIL guiding - just did the best polar alignment ever (and found a VERY simple and quick way). All shots controlled by APT (and focused with APT on-screen - GREAT tool, well worth the $17)

I am VERY happy! Now to process it some to bring it out to it's best.

Larryp
07-10-2012, 07:48 PM
Looking good, Lewis!

LewisM
07-10-2012, 08:29 PM
Oh yeah, forgot to mention, that's NGC 253, but sure most of you knew that :)

Larryp
07-10-2012, 08:33 PM
:thumbsup:

RickS
07-10-2012, 09:10 PM
Nice work, Lewis! I'll be interested to see what you can do with some processing.

brian nordstrom
07-10-2012, 09:45 PM
:thumbsup:.

DavidTrap
07-10-2012, 10:00 PM
Very impressive for 1250mm and no guiding!

DT

pluto
07-10-2012, 10:36 PM
Nice one Lewis, I can't wait to see how much more can be brought out with some processing!

So what's the "VERY simple and quick way" you found to polar align???

ZeroID
08-10-2012, 06:42 AM
Ok, spill the beans, enlighten us all, :D

LewisM
08-10-2012, 08:31 AM
OK, polar alignment. Requires a few additional tools, but sure most you already have:
1. laser leveler/"string" - got mine from Super Cheap auto for $5
2. free android app inclinometer - several available (for iPhone of course too), but this one is a dedicated inclinometer, that also has a digital level bubble in it too - auto converts to inclinometer past 89° :)
3. standard small bubble level - about 9" long, with magnetic strip (helps somewhat)
4. GOOD compass - I have tried the phone apps, but ALL are directly influenced by the magnetic flux of the mount itself. So, what I did was to take a 2 meter aluminium bar, bolt a spare dovetail bar to it (EXACTLY centred). Bent the bar just forward of the mount head down to my latitude, so the bar extending away would be horizontal and easier to read naturally. Mounted a GOOD (expensive) Silva compass on the end, EXACTLY centred again.

So, first step is finding solar noon. There is a website that generates achart for you for your latitude. I'll find it later. Mark the North-South shadow - I marked my driveway with flourescent nail polish for this (and later glow in the dark polish, that reacts to my UV torch I have).

Mount the tripod with the north/south leg on one point of the true south line (depends on your mount - the NEQ6 I have has the rear leg as N/S, whereas the HEQ5 has it's front leg N/S - one day I will get a "quadpod", so I have 2 polar legs :) ). I also added a pointer to the bottom of the head securing bolt (the one that secures the tripod to the head and holds the accesory tray) that almost touches the ground - gives a good alignment with the N/S leg for less fiddling (I aligned it initially using the laser level so the tripod leg and the centre bolt extension would meet at the same linear point). LEVEL the mount - use the built in level or extra level. I don't trust the Synta levels, so I always check myself at several points. Adjust the altitude of the head - I use the digital inclinometer app, as WELL as a carpenter's inclinometer level attached to the compass rail mentioned above, mounted directly above the dovetail plate. NEVER trust Synta's (or others) latitude scales - my NEQ6 is 3° out (my lat is 26.7°, whereas the NEQ6 says 30° when it is precisely lat adjusted. My HEQ5 was quite close)

Now it should be VERY close N/S, but of course the azimuth will be out unless you PRECISELY centred your head. I redo azimuth by again inserting the compass bar, and azimuth aligning, making sure the declination was centred first of course. This removes fiddling later.

Check all is good E/W level (rotate the dec 90°) - I have a permanent mark for dec and RA circles so I know where to rezero the scales etc.

Switch on the mount, do aligment routine (I always do 3 star). Since adopting all these steps, the most I have now been out is 0°20" in alt and az (as indicated by Synscan after the alignment). That's pretty close for goto assignments - always near centred with as low as a 20mm eyepiece. I then run the polar alignment routine (unless I manage to get the mount sub-minute, which HAS happened quite often now) and adjust accordingly. I will also rerun the alignment in APT / PHD once I get my guiding up and running this week.

So, what this has given me is the ability to do 30" unguided. I will usually only do 20", as it minimises high ISO noise and light pollution skyglow from my locale. 45" causes SLIGHT star trailing - only minimal, but enough, though Star Tools can easily correct those.

Now all I need to do is make the cooler box for the camera. Got EVERYTHING in except the Baader IR screen/mirror replacement and the peltier coolers I got from China for $3.95 each POSTED :) And I also need Sirius to get it's Orion order delivered :LOL:

Iain.k
08-10-2012, 02:37 PM
Lookin good mate.

LewisM
08-10-2012, 04:48 PM
Yes David, it's a SUPREMELLY impressive telescope. Worth every single cent! Thanks again! :thumbsup:

I always tought Vixen hype was just that - hype. Now I know EXACTLY what everyone means who owns one!

A BIG thanks goes out to EXFSO and his lightboxes - WELL worth it! (got mine second hand with the scope)

Vasya Pupkin
09-10-2012, 12:25 AM
I see, the popularity of the Sculptor galaxy is very high! By the way, would you, please, answer my question about you job, at last. And what is "IC 6726", I can't found it in the Internet.