The "No EQ" DSO Challenge!

[Nigel G]

10 minutes ago, happy-kat said:

Do you think the better star shapes is the difference between reflector and refractor? I find that observation of your's interesting as the main influencing factor I assumed would be the mount but that was the constant here.

How do the stars compare between ed80 and your 135mm lens. Ian gets great stars with his ED, is that the link a corrected nice refractor.

Yes I believe the refractor is mainly responsible for the stars rather than the mount. There's no spikes, they are smaller and sharper, this is without a flattener as well.

The whole setup is more stable than with the reflector. My camera shutter makes the 150p wobble so a bit of both I suppose.

My 135mm lens also gives fairly good stars, large bright stars seem to blow though.

Nige.

[The Admiral]

59 minutes ago, happy-kat said:

How do the stars compare between ed80 and your 135mm lens. Ian gets great stars with his ED, is that the link a corrected nice refractor.

Kind of you to say so, but if they are I'm sure it's down the gear rather than me! I'm lucky to have an APO, and that helps, and I use a focal reducer/flattener. Even so, spacing needs to be 'tuned' and although I've done the best I can with that, I think I have a bit of focuser droop, or else the 'scope's optics are a bit skew-whiff, because I get oval stars in some, but not all, corners. ST can help here, but if I'm honest I'm often too lazy to mess with that. May be I haven't mastered ST's masking yet .

I'm not a great fan of spikes that reflectors give, and when they are combined with field rotation things can look messy, in my view. It's hard to beat a refractor for Alt-Az in my view, though I occasionally hanker over a much greater light gathering power, and reflectors steal the show there. But I think the mount needed needs to be in a different league. The use of large aperture dobs on a Go-To mount is an interesting path.

Ian

[happy-kat]

So I processed the stack, 32 lights of 30 seconds (only 5 rejects) 52 bias and 46 flats. Canon 1100d, Baader Neodymium filter, ISO 800 Virtuoso mount 135mm old manual Helios lens f2.8 or at f3. NGC 2244 fitting for Valentine's Day.

Immediately DSS showed a very strong gradient at the top, I am now thinking this was caused by some form of reflection hitting the lens from the near by street light, I will have to remember to use the larger flocked flower pot next time. Proccessed in StarTools starting with a very heavy crop and bin 50% then a dabble of all sorts (well more methodical than that). Finished in PSP.

If you look too closely on the left you will see the edge of ther other hideous gradient which is more into the general light pollution level. Terrbile night really really bad clarity and wet refractive air but the first clear for so long had to go out and try something.

Edited February 14, 2017 by happy-kat

[The-MathMog]

Here is the result of one of my only semi-successful sessions with imaging. I am currently using a Celestron Nexstar 130 SLT, and decided to try some imaging with it, until I can afford a equatorial mount. The 130 SLT is infamous for not wanting to do prime focus, so I used the lens from a Baader 2.15x barlow, and screwed it onto the prime focus adapter I have. This seems to work decently, making it able to focus, and it seems to reduce the 2.15x so it doesn't need AS long subs.
It is a stack of only two 30 second exposures 6400 iso (the rest of the attempted exposures had horrible tracking), one 8 second exposure to reveal more of the trapezium, and a few dark frames to remove some horrendous red noise in the lower frame.
Editing is also quite new to me, as the techniques used in astrophotography is so different from anything that I am used to.

It pales compared to a lot what you guys can manage, but it's an accomplishment for me

Next time, I think I will just fire away a ton of 10-15 second subs and stack those, as they seem to be quite a bit more manageable to achieve.

[Nigel G]

4 hours ago, The-MathMog said:

Next time, I think I will just fire away a ton of 10-15 second subs and stack those, as they seem to be quite a bit more manageable to achieve.
 

Well done.

My best image of Orion was only 60 x 20s and 60 x 10s.

Its such a bright nebula, short subs should be fine.  

Nige.

 

[Nigel G]

HappyKat, Perfect for Valentines day

 There has been lots of moisture in the air, what is going on with the British weather. So few clear nights, when it is clear seeing is awful.

Nige.

 

[happy-kat]

The MathMog, you've made a start, excellent. Roll on the next clear night to have a repeat go. When processing be careful not to clip the black point. There are some great videos to get going with on wwe.budgetastro.net by Doug.

They can be followed pretty much using many different editing programs.

Edited February 15, 2017 by happy-kat

[SteveNickolls]

Hi happy-kat,

Well done for even getting outside and having a stab at imaging. The weather since the end of September last year has been the poorest since I started records in 2012. I keep hoping the balance will return soon so we can all get out and image.

Your mention of gradient and light pollution in your image of NGC 2244 struck a chord and of course when we image using our Alt-Az equipment we are limited to the altitude we can image to meaning we get the brunt of the light pollution. While I couldn't see any clear sky a few night's ago I took a photo of how the mist made the the light pollution spilling of the local church below us visible, this is half a second at ISO 400-

They can't even seem to illuminate the spire accurately! Some nights the church looks as if it is on fire. The top of the spire is around 180 feet high and the light shaft goes up quite a long way above that. The church is due East.

I took another photo of the southern sky on the 13th February, two second image at ISO 400 and where Orion ought to be-

Once again good for you having a go imaging in the present conditions!

Cheers,
Steve

[rotatux]

9 hours ago, The-MathMog said:

Here is the result of one of my only semi-successful sessions with imaging. [...]

Nice one for a first. With your barlow it somewhat looks like my first shots with a Mak127, your progress will be fast and easy once you start using longer stacks. 10-15s per sub seems fine given your setup, though you will want longer ones at some point

About your 130 not focusing enough out of the tube... maybe try a lower power barlow such as 1.25X; I don't think ocular projection would gain you anything as with a DSLR the projection distance would be too long and induce a focal multiplier bigger than your current barlow. Or try one of the primary-mirror-raising mods :-P

[happy-kat]

Thank you Steve and Nige, this image might make you laugh it is the view I had Monday whilst imaging MGC2244 currently taking bias files with a bag over the lens. Behind me are 3 more leds one 15 feet away!  I am suspecting my lens shield was not long enough for the direction the camera was pointing. 

 

[noah4x4]

Up until now I had merely dabbled using a Nexstar Burst Colour.  I had secured a few hazy images of Jupiter & Saturn, but they were always disappointing. This is my very first ever effort with an unmodified Nikon D5200 DSLR in a Celestron Evolution 8".  It was a single 8 second exposure at ISO 1600.  The only subsequent processing has been conversion to JPEG and significant cropping. Now awaiting delivery of my wedge so my tracking will be better and to permit longer exposures and the stacking of multiple images. But for a very first attempt it blew my socks off with surprise. I am very familiar with the Orion Nebula,  but to capture some colour was unexpected.

 

Edited February 15, 2017 by noah4x4

[Nigel G]

13 minutes ago, noah4x4 said:

Up until now I had merely dabbled using a Nexstar Burst Colour.  I had secured a few hazy images of Jupiter & Saturn, but they were always disappointing. This is my very first ever effort with an unmodified Nikon D5200 DSLR in a Celestron Evolution 8".  It was a single 8 second exposure at ISO 1600.  The only subsequent processing has been conversion to JPEG and significant cropping. Now awaiting delivery of my wedge so my tracking will be better and to permit longer exposures and the stacking of multiple images. But for a very first attempt it blew my socks off with surprise. I am very familiar with the Orion Nebula,  but to capture some colour was unexpected.

 

Well done  It looks a lot like my first ever image. Get ready for a challenging journey  

Nige.

[Herzy]

Has anyone been able to capture the comet out now? It's up in the morning or so I've heard.

[The-MathMog]

8 hours ago, Nigel G said:

My best image of Orion was only 60 x 20s and 60 x 10s.

Its such a bright nebula, short subs should be fine.

Thanks guys! Good to know. Quantity seems to work miracles at times, I just need to figure out how I best improve my mounts tracking too. Not sure if Sky-align, two star align or solar system align is the best. And I suspect that I need to add a small amount of weight at the back of the telescope, for when shooting at objects low in the sky, as the camera weight might pull the telescope down a bit?

3 hours ago, rotatux said:

Nice one for a first. With your barlow it somewhat looks like my first shots with a Mak127, your progress will be fast and easy once you start using longer stacks. 10-15s per sub seems fine given your setup, though you will want longer ones at some point

About your 130 not focusing enough out of the tube... maybe try a lower power barlow such as 1.25X; I don't think ocular projection would gain you anything as with a DSLR the projection distance would be too long and induce a focal multiplier bigger than your current barlow. Or try one of the primary-mirror-raising mods :-P

I will definitely want to move more into the realm of longer exposures, hence why I am saving up for either a HEQ5 or maybe EQ6?
The barlow lens I use now, advertised that if you only used the lens part, it would only magnify by 1.3x, which I then added to the prime adapter. It seems to be a bit more than 1.3x though.

I have looked a bit into moving the primary mirror too, but I am not sure if that is something I want to try out, as I am not veeery good with stuff like that, and it would be a shame if I ruined the only OTA that I have

[Stub Mandrel]

This lovely widefield photo by Bob King on the Sky and Telescope website:

[Nigel G]

16 minutes ago, The-MathMog said:

 I just need to figure out how I best improve my mounts tracking too. Not sure if Sky-align, two star align or solar system align is the best.

I would suggest the 2 star align for DSO's. Its what I do with mine.

Nige.

[Nigel G]

19 minutes ago, Herzy said:

Has anyone been able to capture the comet out now? It's up in the morning or so I've heard.

I have been waiting for a chance but its been cloudy the whole time  

P45 Honda comet. Mag 7 atm in Canes Venatici

[happy-kat]

I did 2 star align and had to make my setup rear heavy bias to image in the east otherwise I had altitude trailing. I will assume I will need to reverse this bias when facing west. Don't forget the star selection within 90 degree but no more than 130 apart and a altitude between 30 to 60 degrees (from my memory). Check your manual for alt az star selection for aligning it was different in my manual to the normal eq star selection parameters. Synscan v3.

[SteveNickolls]

6 hours ago, happy-kat said:

Thank you Steve and Nige, this image might make you laugh it is the view I had Monday whilst imaging MGC2244 currently taking bias files with a bag over the lens. Behind me are 3 more leds one 15 feet away!  I am suspecting my lens shield was not long enough for the direction the camera was pointing. 

Blimy, you need ARP Warden Hodges from 'Dads Army' to, "put that light out". Keeping on the military theme you deserve a medal putting up with that streetlight!

Good luck imaging.

Steve

[happy-kat]

The only consolation is the four the other way (3 visible from front) block north and north east, less of a loss in the scheme of things. That light is pretty much due south and I am long gone to bed before they are turned out!

[Filroden]

I thought I had a clear evening yesterday so I wanted to see if my new spacing on the camera improved my star shapes (and also hopefully get some more colour data for my Rosette image). After a new set up at the end of the garden I found my new mini-PC was just on the edge of wifi range and the connection just wasn't strong enough to use remotely. I'll have to test more in daytime but I swapped to the laptop and sat outside (thankfully a much warmer night than usual). The new spacing meant I needed to find the new focus points for each filter which took about 10 minutes. Autofocus worked so well on the Ha filter that i reduced the exposure time down from 10s to 5s and went from bin4 to bin2.

I set up a new sequence to capture 10x60s each of RGB and Ha, hoping to run it at least twice before the forecast clouds came over. I managed 10x60s of Ha and RG.

On review of the data, it looked of similar (if not slightly better) quality than previous sessions (much less gradient in the R and G). However, when I blinked through the images the field rotation was spectacular. Zooming in on individual subs showed beautiful trails moving clockwise around the Rosette  I should have know better and a) checked the first sub before committing to the sequence and b ) probably reduce the exposure to 30s. So I can't use this data to check how flat my field is.

I haven't taken flats yet but I did a quick integration without any calibration and all three looked good in the central area. Probably good enough to throw into a bigger stack once I've calibrated them since the older data has elongated stars in the corners because of poor spacing.

Isn't it funny how routine makes you forget the basics. By setting up near my kitchen window I could only image to the east so field rotation was never really a major concern (wind and mount limited my exposures to about 60s). Because the Rosette had moved so far round I needed to set up in a new location and I never paused to think I was now imaging south where rotation becomes the single limiting factor for my system!

[SteveNickolls]

22 hours ago, Filroden said:

Isn't it funny how routine makes you forget the basics.

Hi Ken,

I'd add to the list with lack of clear night skies and age. I'm sure you will surmount this hurdle. Good luck.

 

Best regards,
Steve

[happy-kat]

OK I'm ready to take on the street lamp I've flocked an a4 sheet of fairly  tough acetate plastic and that is holding shape well and giving me a long tube of protection. 8 rubber bands later and it's not going anywhere.

[happy-kat]

My A4 flocked tube worked great. Filthy moist air again but a lot warmer outside I had my dinner whilst I sat imaging out there. I'll have to pass on the rosette now as I think I'm going to lose half the images I took as my target drifted over to the other side and my mount was weight biased for a rising object not a declining one. Had to do two star alignment three times to get tracking good enough most likely due to my poor accuracy contorting around objects to sight through the rdf. So my one given win is my flocked tube no nasty street light direct reflection on the lens. Tomorrow I'll see what I managed. Before I forget lens was set at f3. That's 6 times using my battery now and still half charged.

[happy-kat]

Well I can right all of those off, even though I had 52 good images out of 61 the general light gradient in that direction was hideous anyway so even though more subs and a bazzoka lens shield the final result is worse than first time around. So next clear night I willl revert to the back garden and the neighbour's hedge and restrictive view but where I think there is less sky glow dome in the Westerly direction.