The Astro-Imaging Thread

[Green Baron]

What do you mean, betrayed ? dss is quite straightforward. Just choose lights, darks, biases if you have, click "Select all" and then click "register images". dss does the rest and saves a fits in the lightframes directory. Maybe try just the lightframes first ?

You can stack manually with fitswork or pixinsight and will have my respect if you do so. You will have to walk all the way on foot, where dss offers a quick ride.

 

[munlander1]

single light plus dark after playing with the histogram:

Another attempt:

And a single light:

So the error I had with dss was it said only one image could be stacked. I would explain more, but have to go.

[tater]

I took this image with a plate film camera on the 24" (0.6m) Boller and Chivens Cassegrain reflector at the Capilla Peak Observatory back in the 1980s. It was before we installed the CCD, rather a long time ago. In fact, we removed the photometer that had been on the scope, and put the plate camera on as a lark since the film in the fridge had languished with sometimes intermittent refrigeration, and much was moldy (you can see an emulsion issue on the lower right).

I hand-guided the scope on a ladder in the dome, and I developed the plate as well in the darkroom (chemicals were also pretty ancient).

Edited July 1, 2017 by tater
because photobucket stinks

[munlander1]

So well on the dss error, it said that only one frame could be stacked and that I needed to adjust the star detection settings so it could better match in to the reference frame. When it does stack I get a black photo or a photo with multicolor, vertical lines. Is there anything I could do? 

 

I also tried doing the 4 lights that were as similar as possible.

I also posted the above images from my phone. Will try to post them from the computer. They are much better.

Edited February 17, 2017 by munlander1

[YNM]

(sorry for digging a bit)

On 2/10/2017 at 5:27 AM, munlander1 said:

So my telescope cover has one hole in the left (or right, depends on how you look at it).  

Should the other side be cut out?

If you have a filter, then yes. Best for the resolving power.

But if you don't have... I don't recommend only using that at all. Also, I thought they are separate caps already (no need to be cut off) ?

Edited February 17, 2017 by YNM

[munlander1]

10 minutes ago, YNM said:

Also, I thought they are separate caps already (no need to be cut off) ?

I don't know if this answers, but i did not need to cut it. Was just wondering if it was intentional or left over plastic from molding.

[kurja]

10 hours ago, munlander1 said:

And a single light:

So the error I had with dss was it said only one image could be stacked. I would explain more, but have to go.

Looks like there are quite few and blurry stars in the frame, DSS might not find enough of them to align with. I don't really use DSS... Maybe you could try something like this http://ukastroimaging.co.uk/forums/index.php?topic=30566.0

Edited February 17, 2017 by kurja

[Green Baron]

Yep, it is ok for a first try, but it's not ready for stacking. You didn't tell us how you made the photos, but in any case you'll need to find the primary focus first (use a Bahtinov mask), and the camera chip must be aligned exactly perpendicular to the optical axis. Check the collimation and be sure that nothing shakes camera or scope during exposure. Was it windy or did you hold the camera by hand ?

Edit: btw., the star on the right looks like a typical coma-star (comatic aberration, typical for short newtons with a parabolic mirror). But before taking care of this have the above criteria corrected first, especially alignment and collimation. What camera did you use ?

Don't loose patience. It took me over a year. And try to gather all information you can get. I would try cloudy nights for example or another community specialised on all things astro as well !

 

Edited February 17, 2017 by Green Baron

[munlander1]

4 hours ago, kurja said:

Maybe you could try something like this

Thanks, will hopefully try something like this tonight or tomorrow.

2 hours ago, Green Baron said:

Was it windy or did you hold the camera by hand ?

 

Yes, it was some what windy when I took them. I am using a camera bayonet secured to the eyepiece.

2 hours ago, Green Baron said:

Check the collimation

I forgot about that. 

2 hours ago, Green Baron said:

have the above criteria corrected first, especially alignment and collimation.

Will try tonight. 

2 hours ago, Green Baron said:

What camera did you use ?

I used a cannon xti.

2 hours ago, Green Baron said:

I would try cloudy nights for example or another community specialised on all things astro as well !

Will check out CN if I remember tonight.

Thanks!

 

It gonna be clear ALL NIGHT LONG. There will be Scott Manley, kerbals, and food. Only for me though.

Edited February 17, 2017 by munlander1

[Green Baron]

2 hours ago, munlander1 said:

 

Yes, it was some what windy when I took them. I am using a camera bayonet secured to the eyepiece.

 

Try the primary focus, no eyepiece, no correctors, no filters, no bottoms of glass bottles. That means to directly fix the camera to the focusser tube with the appropriate adapter. Will post a photo link later of what i mean.

Eyepiece projection complicates things because you have two foci to hit. Also it adds to the stack of possible errors and mistakes :-) Like balance, focal plane, distortion by lenses, etc.

Good luck tonight !

Edit: if you mean with cannon xti the canon eos400d here's what you need to get the camera in the primary focus:

http://www.telescope.com/Accessories/Adapters-Cables/Orion-Superwide-2-Prime-Focus-Adapter-for-Canon-EOS-Cameras/pc/-1/c/3/sc/40/p/115062.uts

Just an example, doesn't have to be that brand, i just searched these because you already have an orion telescope.

The above is a one piece adapter. For more flexibility in the future it might be wise to split the adapters in two:

http://www.telescope.com/Orion-T-Ring-for-Canon-EOS-Camera/p/5224.uts?keyword=t adapter

and then

http://www.telescope.com/Orion-Tapered-2-to-T-thread-Adapter/p/113926.uts?keyword=2 adapter t

 

Edited February 17, 2017 by Green Baron

[munlander1]

Ok, will try prime focus. Thanks!

[_Augustus_]

Took some shots of the Moon the other day with my Celestron NexStar 4SE and modified Logitech Quickcam Pro 5000. Captured in SharpCap and processed in Registax. 3 km per pixel.

http://imgur.com/a/9o6tD

[YNM]

On 02/17/2017 at 9:53 AM, munlander1 said:

I don't know if this answers, but i did not need to cut it. Was just wondering if it was intentional or left over plastic from molding.

They are intentional, often to make viewing the Moon or bright planets easier. (and here, often to install filters as well.)

[_Augustus_]

The Moon from 3/4/17. I figured out what those sliders in Registax do. Composite of 19 images.

Jupiter from 3/17/17. I was unable to keep Jupiter in the field with a Barlow due to image shift and tracking errors.

Both were taken with my Celestron NexStar 4SE, and Logitech Quickcam Pro 5000 (which I got for $2).

Edited March 18, 2017 by _Augustus_

[Green Baron]

Well done :-)

What are the dark spots ?

 

[_Augustus_]

2 hours ago, Green Baron said:

Well done :-)

What are the dark spots ?

 

Dust on the sensor. I didn't know what a flat frame was at the time.

Edited March 18, 2017 by _Augustus_

[munlander1]

30 minutes ago, _Augustus_ said:

Dust on the sensor. I didn't know what a dark frame was at the time.

Do you mean flats? Darks take care of hot pixels.

[munlander1]

@_Augustus_ was I right?

[Green Baron]

17 hours ago, _Augustus_ said:

Dust on the sensor. I didn't know what a flat frame was at the time.

If the sensor has a protecting glass you could carefully clean that with a tissue for cleaning eyeglasses, or if you have a lens cleaning kit (cleansing liquid, paper, small bellows) you could use that. Anyway it's a good idea to have one at home. If the sensor is exposed you could try to puff the dust off with a bellows or, if you have extremely calm hands and sharp eyes and loupe you could carefully pick the dust up with a cotton bud dipped in cleansing alcohol that evaporates without leaving residue.

Flats can correct the dark spot, but they don't regenerate the missing parts of the picture ...

 

Edited March 19, 2017 by Green Baron

[_Augustus_]

Jupiter, 3/19/17. Used a Barlow this time. Io was transiting but I can't really see it; if it is in the picture it's nothing more than a smudge.

 

On the other hand, the polar regions, equatorial belts, and even the Great Red Spot are very easy to see!

I am going to try a timelapse tomorrow night.

Edited March 20, 2017 by _Augustus_

[Green Baron]

Thanks, very impressive !

So cool to see how a bouncing ball reveals itself as planet.

For the conditions you have surely beaten the hell out of it !

 

[_Augustus_]

1 hour ago, Green Baron said:

Thanks, very impressive !

So cool to see how a bouncing ball reveals itself as planet.

For the conditions you have surely beaten the hell out of it !

 

Yeah, apparently seeing was something like 2/5 last night. Doesn't look like it'll improve either...

Edited March 20, 2017 by _Augustus_

[Green Baron]

Image processing is driving me nuts. Nobody writes a documentation any more these days. You need to watch video tutorials (vt). But they are like tv cooking shows with prepared prerequisites: they work. As soon as as you cook your own soup i mean use your own data nothing works as it did in the vt. Did they mention you had to check the "Lightness mask" box before applying the changes globally ? Or that you need linear data for the process to work correctly ? Or need the "StarAlign" process instead of "ChannelMatch" to match shifted colours in an rgb combination ? Or select three different previews to check the settings ?

Frustrated after several days i visited a forum where the high and mighty discuss, managed to register after answering 20 silly question 4 times to get through the anti spam wall, browsed through all the spam to look if anyone else had the problem before, found nothing, posted my question and get a wavy answer like "did you check the "Lightness mask" box ?".

*sigh* "Thanks for the reply, but, yes, i did ... ?"

 

Vts are just a waste of time and bandwidth. I just read that someone has written a book about astro imaging software. I hope i find the answers that i am looking for there.

 

/rant

 

Edited March 22, 2017 by Green Baron

[kurja]

Learning curve is steep for sure. Do try to think what the bells and whistles actually do, and why doing so is useful, and you'll get more out of those tutorials. Hopefully.

[Green Baron]

One day soon(tm) ...

In the same forum someone was ranting exactly over that learning curve and expressed his thoughts about vts with less reserve than i did :-) He said that he tried several hours and didn't even get behind a certain process in the workflow. Then he got an answer from someone who claimed to do astroimaging since years and just scrapped the work of 160 (sic!) hours on a single image just to start all over again.

Conclusion: keep smiling , things could be worse .