My First Ever Nebula Attempt - Tarantula

[mikeyjames]

Hi all,
I had a go at imaging the Tarantula last night.

18 x 20 second exposures @ ISO 1600 - then I accidentally turned off the mount.
10 x Dark frames
10 x Flat
10 x Bias

Used Deep Sky Stacker. The resulting image looked near grey scale so I had a stab at brining some colour out in Paintshop Pro. I think the colours look a bit tacked on but overall I'm happy with my first try.

Happy for any advice.

Cheers
Mick

[Atmos]

Much better that my first, second and third nebula attempts :) Doesnt help turning the mount off though ;)

[barx1963]

Hi Mick
Well done. The spider is a very hard target. I have had almost no success with it in my time. Personally I almost prefer it as a visual target!
What gear are you using?

Cheers

Malcolm

[mikeyjames]

Thanks Colin. I didn't realise until I saw pic number 19, then realised I had turned off the mount rather than my phone charger when packing up some of the gear.

[mikeyjames]

Thanks Malcolm.
200mm/1000 Skywatcher Newt
Canon 60D (modded)

I wish I could see things like Tarantula as a visual target. When I looked at the piece of sky the scope was pointing I could barely see a single star.

[raymo]

Being as you can see the Tarantula with the naked eye, why can't you
just centre it in your finderscope?
raymo

[mikeyjames]

I couldn't see it from where I am in Sydney. I can only barely make it out looking through the main scope.

[raymo]

O.K. so I'm gathering that your light pollution is pretty bad.
raymo

[mikeyjames]

It's a combination of general Sydney light pollution and mission control next door (which is directly in my view of the Tarantula part of the sky). I find nebulas one of those things where I'm asking myself, "is there something there or am I imagining it?" The view for the western sky is less light polluted but still no clear cut views of nebulas.

Maybe some type of filter may help - I've read that Lumicon make a good one and the Orion Ultrablock is good too.

At present, I need to get the goto pretty accurate, then when it slews to a to a target I take a pic and then centre it from that.

BTW - that tip you gave me about shooting the moon really paid off, I got a couple of really good shots last night.

[raymo]

Many people here on IIS swear by NPB nebular filters. Their service is good,
and they sell cosmetic seconds. My 1.25" cosmetic second was $75, and
the only fault was part of one letter of a word on the rim was missing.
Glad you had some luck with the moon. A $15 webcam with a 2x barlow
is a popular way of getting pin sharp lunar shots. Just have to learn the ins
and outs of Registax or whatever other software you are using. When the
seeing is really good you can get nice single frame lunar shots, but video
is really the way to go; you can of course do video with your DSLR.
raymo

[gaseous]

The DGM NPB filter will be a godsend if you're trying to see fickle nebulae in light polluted skies -it will certainly confirm if there's something there or your mind is playing tricks! Even more rewarding if you can get yourself to a dark sky site.

[mikeyjames]

Thanks raymo

[mikeyjames]

Thanks Patrick

[thegableguy]

Re being unable to see the Tarantula through the scope...

When I look through the viewfinder of my DSLR through my 200/1000mm Newt, I can barely see anything. When I take the camera out and use, say, a 25mm eyepiece, I can see vastly more. The camera's viewfinder is nowhere near as bright as an eyepiece - only bright targets like clusters or planets (or the occasional nearby nebula like Orion) are visible through it. It's a pain having to refocus etc, but it's either that or take a bunch of high-ISO exposures and guess which way to slew the mount to centre the target.

You probably already know that, but just thought it was worth making sure!

[mikeyjames]

Hi Chris,
I'm using a modded Canon 60D. I am having trouble viewing anything other than Moon, Saturn, Venus, and sometimes Mars through the viewfinder. Even with ISO set to its highest and shutter speed set to 30 seconds nothing like Orion Nebula or clusters in my viewfinder. So I end up doing exactly what you said is the less desirable option, taking a high ISO image and then trying to move the scope to get it in the centre.

I wonder if there is some setting on the camera I am getting wrong.

Thanks
Mick

[raymo]

Mick, the viewfinder is purely optical; you see the same view with the camera switched off, so settings are irrelevant. The night sky is dim through the viewfinder because of the focusing system built into it. There used to be
different gratings available for different purposes, one of which
brightened up the finder somewhat; maybe they are still available.
raymo

[Regulus]

It's a pretty good result for first try, and especially given your circumstances. Given it is your first go, and in trying situation, I have to wonder how much better it would have been from a better site, and i hope you can get to one one day.
Well done - Trev

[mikeyjames]

Thanks raymo. I've just realised I had the terminology wrong. I meant the LCD screen on the camera.

The gratings sound interesting, I'll have a look around and see what I can come up with.

[mikeyjames]

Thanks Trevor. A dark site would be great and I will get there one day. Before I do that I want to learn how to accurately set everything up and find things and there is still a long way to go.

I'm 98% sure I will stick with it. Generally I love a challenge and lose interest in something quickly once I get pretty good; I don't see this ever happening with this hobby as there is always room for improvement.

[thegableguy]

Ah! Then yeah, you're never going to see much with that as it's limited to 1/25 or 1/30 expsures.

You're better off using your eye to the viewfinder, but that's still very dim because of the focusing mechanism blocking part of the light as Raymo said.

You're never going to see anything with the DSLR, either through the viewfinder or the rear LCD, anywhere near as well as you'll see it through a 25mm eyepiece. Yes you'll have to refocus each time, but at least you'll actually see your target.

[mikeyjames]

Hi Chris
What do you mean by limited to 1/25 or 1/30? Is that exposures quicker than this will show nothing at night on the screen? Is this limit just for astrophotography/low light photography ?

Even when I set ISO to 12800 and exposure to 30 seconds there is nothing on the screen other than the moon, Saturn, and Venus; sometimes Mars makes it to the view screen too.

I may also try connecting the camera to my laptop and see if that helps.

At the moment it's get the goto as accurate as possible and them take the picture and hope the target is somewhere in there. Then I adjust, taking note of what I did, take next shot hoping I get it closer to the centre of the pic.



Thanks
Mick

[DarkKnight]

Hi Mick,

Firstly, apologies for not answering you in my thread as I was on a mission to get my mount hardware sorted and I tend to get tunnel vision.

I've picked up a couple of things along the way that may help you. I also can't see the SCP which makes my polar scope useless. However there are apps available to enable you to get true south at solar noon by using a plum-bob, or a piece of string with a weight on it, and marking the shadow line on the ground where you set-up your tripod.

This is the one I'm going to try..... http://www.solar-noon.com/ If you get that pretty close I figure it should make drift aligning quicker and easier.

re focusing: I have given up on trying to use my camera's Live View screen and also tried some phone apps to no avail, too small, too dark and too blurry. Use your laptop as there are heaps of camera control apps available for Canon and you may even find a freebie that works. I think I tried four before I found one that worked for Nikon. Backyard EOS seems to be a popular pick for Canon.

I did a lot of research on LP filters and eventually settled on an Optolong UHC Clip-on, however fitting it was not straightforward on my Nikon and I haven't used it so can't comment on it's effectiveness, but it seems to be well regarded by those in the know.

You asked whether I thought your photos were worthwhile. Worthiness is highly subjective and will vary greatly depending on an individual's expectations. I will say that no photo is unworthy if it is used as part of a learning curve and a benchmark for improvement.

Mick, you seem to be heading in the right direction by seeking advice from those more experienced. I keep telling myself that the only dumb question is the one that I don't ask. :shrug:

PS: I'm sure you are aware of these two apps for planning your shoots.

http://app.photoephemeris.com/ll=-32.676328,151.609493&center=-33.9369,150.9839&dt=20140914033400%2B1000&z=15&spn=0.01,0.03&sll=-33.934840,150.983545

and http://www.stellarium.org/

[mikeyjames]

Hi Kev,
Appreciate the tips and links. I have been using Stellarium and it is really helping me to learn the sky.

The photographic app I have never seen before. I'll give the solar noon thing a go as well. Raymo also gave me some really good instructions for DARV method for drift aligning which I plan trying out when work and weather combination decide play ball for me. I'm having a couple of weeks off after Christmas so hope for some clear sky then too.

I have made a contraption that fits between the legs of the tripod for pointing to true south with a proper Sylva compass with magnetic declination set, plus I have an inclometer for the angels.

I will set up one day and ask it to go to sun, moon, Venus and it works reasonably well - not perfect but all targets within FOV and tracks moon or sun within FOV for an hour and goto finds things later in the evening. Then next day it may find the sun but won't do moon, so I manually adjust things until I can slew back and forth and I may have trouble locating things - the Tarantula was found by accident while looking for a supernova remnant in the same vicinity.

Doing the manual adjustments and then parking the scope has really shown me how minor errors can cause big discrepancies. The other day, the difference between my setup and adjusted setup was 1 mark on the Dec scale of my NEQ6 and such a small change on the RA scale it would be difficult to quantify. Yet enough to totally miss the moon when slewing from the sun.

I do find the errors seem to be worse for objects higher in the sky - not sure if that means much but objects - including sun, moon, Venus - seem to be located and tracked better when lower in the sky.

I know the easiest way would be to mark the place on the ground where the legs of the tripod go and mark all other settings on the mount so I can repeat a good setup, but I would rather keep setting up from scratch each time until I learn to get it right.


I have a NPB filter I have been waiting to try out - I purchased one of their seconds for a bit cheaper and can't see anything wrong with it http://www.npbfilters.com/about.html

Will definitely give Backyard EOS (or something like it) a go.

As for my pics. Personally I was/am really happy with them for my first try. I was just wondering what level you are aiming at - maybe being too hard on yourself??

Sometimes I wonder when I ask questions which philosophy I should follow:

1) The only stupid question is the one not asked

or

2) better to let people think you're stupid than open your mouth and prove it ;)

No, I plan to keep asking heaps of questions :)

[DarkKnight]

Cheers Mick,

I guess I am pretty hard on myself but I figure that if I put in the time and the effort I should get pleasing results, at least to me.

Here is my first serious attempt at astro photography. I guess I thought it turned out well enough to encourage me to get involved.

And I also found out that post processing astro shots is a whole new ball game. The shot was taken out of town but unfortunately facing back toward the light pollution emanating from Maitland, hence the hunt for a LP filter which are like rocking horse poo for Nikon.

This was a single frame with a Nikon D800 + Samyang 14mm f2.8, 30secs, f2.8 at ISO1600.

Since then I've tried stacking with DSS with lower ISO and shorter shutter times. I'm aiming at getting my ISO down to 200/400 with much longer exposure times. I'm hoping I've finally got my HEQ5 Pro sorted and can get out and start chasing nebulas.

[mikeyjames]

That pic would definitely get me quite encouraged to keep going. What did you use to fix up the light pollution in the 2nd one?

Yes, processing the images is a whole new ballgame. All I seem to manage at the moment is to make the pics worse.

[DarkKnight]

The first is the shot SOOC.

I think I used just about every slider in Photoshop and still couldn't get rid of the LP. That's the red/magenta glow in the bottom RH corner.

The best way to get rid of it is to find a dark site. :stargaze:

[mikeyjames]

You should have told me the reddish bit is ionised hydrogen - I would have believed you:)