Our Beautiful Universe - Photos and Videos

[davenn]

I got some strange artefact (darker middle spot ) on image of Sirius. ??

probably due to out of focus and you are seeing the shadow of the secondary mirror of the telescope

And secondly I attach image of Sun take directly (without) filter…-I am not sure if line on lower right quarter could be siluete of sun?

not a wise thing to do, it can burn out camera sensor etc
Are you sure it was the sun ? looks like blurry craters in there ...
maybe they are out of focus dust spots on the mirror ??

Now I already order solar folie for filter-do you some have experience with it?

that's good to hear
don't do any more solar pix without one Dave

 

[DennisN]

Cannot remember specifically what I said now?? so let's try again

I remember you recommended experimenting with single images.

Yes, a steady mount is essential and I suggest that if you really want to make good use of that scope

Yes. There are some other problems with the telescope which makes me a bit reluctant to buy a better mount, for instance when I use the star diagonal I can not focus with the eyepieces, since they get just a bit too far away from the focusing point due to a limitation of the focusing mechanism . I am considering fixing that, if I can, though.

I am considering building a small DIY Dobsonian mount, since it seems to be a quite good design both for targeting reasons and stability, and I watched a couple of youtube videos where people were building mounts. I think it would be fun to do.

Still a good effort considering what you were dealing with keep experimenting

Thanks, I will.

I would also suggest that you do more experimenting with just single images.
You will be surprised with the results that can be achieved !
Stacked images from video frames can produce awesome images but you need a steady platform to begin with

Thanks, I will do that.
I took some single images too, and also extracted some single images from the videos I took, and I compared them with the stacked image and the stacked image was only marginally better. I watched the Moon via the computer screen when I was filming, and I noticed 1) a lot of noise artifacts from the camera (at least I think so, and this could maybe be reduced by filming dark frames which I did not do this time) and 2) a lot of noise due to the atmosphere.

 

[davenn]

Hi @bruha

Sorry, I didn't answer the second part of the question ...

Now I already order solar folie for filter-do you some have experience with it?

Yes, over the many years I have done many solar white light photos with the basic filter both using
foil as well as silvered glass. I would use these for photographing solar eclipses, Mercury / Venus
transits and for sunspots.

here are some examples ...

lots of sunspots

closeup

Transit of Venus and some spots

solar eclipse ... this image was on the way to totality about 10 mins after this pic

Annular solar eclipse ( where the moon doesn't fully cover the sun - it's a little too far away)

Cheers
Dave

 

[davenn]

I took some single images too, and also extracted some single images from the videos I took,

Lets see an example of a single image, generally they will look better than a single frame from a video
unless it's HD video.

and I compared them with the stacked image and the stacked image was only marginally better.

The stacking part in Registax is reasonably easy, you of course realize that you get it to only stack the
best ~ 50% of the frames ? ( you probably do )
It's the processing of the stack that is the tricky part and to be honest, when it comes to solar, lunar
or planetary stacks, I still have a lot to learn to produce a decent result
Stacking and processing deep space single frames is much easier.

I watched the Moon via the computer screen when I was filming, and I noticed 1) a lot of noise artifacts from the camera (at least I think so, and this could maybe be reduced by filming dark frames which I did not do this time) and 2) a lot of noise due to the atmosphere.

1) Don't think they do darks video ... maybe they do ?, I have never heard anyone say such.
2) Atmospheric "noise" is what doing the stacking helps to overcome ... keep your used frame count
to a max of around 50% ... Registax will determine the best frame to use.
2a) ... you will learn that you have to pick your nights ... this also applies to doing solar imaging
(day time, obviously) the atmospheric conditions can vary quite dramatically.
One night, the image can be shimmering lots because of the instability and it's just a waste of time
trying to do anything. Other times not so bad or really steady.
You will be able to judge that by just looking through the eyepiece even before attaching the camera.here's a couple or examples of single shots of the moon ...
The first one using my Canon camera and telephoto lens

This second one is using an astro camera ZWO ASI 1600MM on my Skywatcher 120 x 1000mm
refractor telescope ( image captured in the SharpCap program)

Gosh, the forum software really destroys the image quality

Dennis, if you are interested, PM me and let's swap email addy's or maybe you would be
interested in joining my facebook astro group and see what others are getting up to
By either of those ways at least you / I would be able to send / receive images in their original
quality directly to each other
Dave

 

[DennisN]

Beautiful photos, @davenn!

Lets see an example of a single image, generally they will look better than a single frame from a video
unless it's HD video.

I'll be back...

 

[DennisN]

Lets see an example of a single image, generally they will look better than a single frame from a video
unless it's HD video.

I noticed I had deleted the single images because they were too bad.
But I checked with some other images, and the capture via SharpCap was in the resolution 1280 x 960 both for single images and video. The movies were captured in 30 frames/s.

There is one issue I forgot to mention though: I did not use a moon filter, which I should have. This was because I could not fit the variable polarizing filter I've got with the setup I used at the time. And this was just an initial test with the webcam. Instead of filtering, I changed the exposure time and brightness in the software SharpCap instead. Quick and dirty .

Nevertheless I extracted two of the best images from two different movies and here they are
(directly extracted, no modifications and with the original 90 degrees rotation):

I also uploaded one of the original movies to youtube (which youtube probably compressed in some way), but anyway here it is (note that the image is rotated, and wobbles quite a lot, maybe because of small vibrations that traveled through the mount to the scope, I'm not sure):

 

[davenn]

There is one issue I forgot to mention though: I did not use a moon filter, which I should have. This was because I could not fit the variable polarizing filter I've got with the setup I used at the time.

I never use a filter on the moon. There's really no need to even if the moon is nearing or is full moon.
Just drop the exposure time so that the image isn't over exposed. You are just adding extra glass to the optical path
that will further distort the resulting image

The best times to image the moon and get the most
detail of craters etc is up to and a little past first quarter ... as in my examples above. There's nothing wrong with imaging the
full moon if you just want that, just don't expect a lot of detail as most of it will get washed out in the brightness

I changed the exposure time and brightness in the software SharpCap instead. Quick and dirty .

yup, exactly

Nevertheless I extracted two of the best images from two different movies and here they are
(directly extracted, no modifications and with the original 90 degrees rotation):

OK ... now, I'm not sure how much of the blur is 1) the moon motion, 2) the unknown quality of the optics in the scope,
3) the quality of the webcam, 4) focussing or 5) a combination of some or all 4 of the above.

Referring to #2, how does the moon look through the scope visually ... eye to eyepiece ?
Is it reasonably sharp with good detail ? Do you see any colour fringes around the edge of the moon ... like a poor rainbow ?
If it looks reasonably respectable, then the blur can be put down to the other 3 things ... motion, focussing, camera.

Registax ( or any other stacking prog) will really struggle to stack a set of images that are moving across the field of view ... seriously!
And then on top of that other vibrations

This is where my comments on a solid mount become apparent ... You will see those comments in this thread and any other one where
people are struggling with imaging ... I really cannot stress it strong enough !
There's no point having a $2k scope on a crappy mount and even a very good mount will make a middle of the road scope perform well.

Hence my comments a few posts back ... spend money on a decent mount, even if it is just for this current scope ...
at least you will have a decent mount for a better scope in the future

Other big advantage of a decent mount is that it will be one you can do tracking with it, as all the respectable ones come with different
tracking speed settings, eg ... Solar, Lunar, sidereal ( for tracking deep space objects ( galaxies, nebula etc)
This is because the sun, moon and stars all move at different rates across the sky.

am considering building a small DIY Dobsonian mount, since it seems to be a quite good design both for targeting reasons and stability, and
I watched a couple of youtube videos where people were building mounts. I think it would be fun to do.

Dobo's are great, do a decent one with say an 8" mirror, don't mess around with anything smaller ...6" or less ... will lead to disappointment
Keep in mind with a dobo, you will still have no tracking and you will need to confine imaging to single very short exposure single shots
Most scopes on dobo mounts are Newtonian reflectors and generally low f-ratios, eg f4.5 to around f7 and that tube could always be
transferred to a tracking mount at a later date
OK that will do for this post ... a pretty long spiel haha
Will let you digest it and make any comments/questions Dave

 

[bruha]

Hi and thank you very much for answer and images-it looks very interesting -is there some difference in filtering function between foil as well as silvered glass?

Lot of succes hi

 

[DennisN]

I did some more "mobile astrophotography" a couple of days ago, that is, photographing the sky with only a mobile phone (LG G4), like I've done before.

Date: 26 April 2019.
Stacking software: DeepSkyStacker.
Detection software (online): Astrometry.net.

Big Dipper/Ursa Major:
(20 stacked photos, ISO 800, f/1.8, 4 seconds exposure per photo (if I remember correctly))

With more contrast:

I also took some photos by putting the phone on a flat surface, pointing the camera straight up into the sky:
(20 stacked photos, ISO 800, f/1.8, 4 seconds exposure per photo (if I remember correctly))

Detections by Astrometry.net:

I also took multiple sets of photos, trying to make a larger image by making a panorama.
I have however not been able to make this work, since none of the software I have tried has been able to stitch photos with merely stars in the photos. I have also searched for specialized software for this job, but I haven't found any, so I don't know if this is possible at the moment with available software. If anyone knows more about this, I would very much appreciate information about it .

And here's another photo from my observation point out on a beach:
(1 photo, ISO 800, f/1.8, 15 seconds exposure)

 

[DennisN]

OK that will do for this post ... a pretty long spiel haha
Will let you digest it and make any comments/questions

Thanks for your support, @davenn! I will digest it and reply with more details later. I have got a better a tripod now (which can be elevated to about 1.5 meters), and I also have managed to make it more stabile than it was. I'm working on doing a mount for the scope on it. And I have got some ideas I will try to improve the focusing mechanism.

 

[DennisN]

I found a https://live.staticflickr.com/65535/47681612592_63286714b4_c.jpg today at a second hand store for $10, and I took it out with the scope to the park today, since I was going to try to take photos of the Sun (with a sun filter mounted in front of the scope). I set up the tripod at a good place and looked around for my bag with filter, eyepieces and camera mount. But it wasn't there, I had forgot the bag at home .

We have very clear skies here at the moment, and I am thinking of going down to the beach tonight to try out some things...

 

[davenn]

I found a https://live.staticflickr.com/65535/47681612592_63286714b4_c.jpg today at a second hand store for $10,

nice find

 

[Andy Resnick]

I also took multiple sets of photos, trying to make a larger image by making a panorama.
I have however not been able to make this work, since none of the software I have tried has been able to stitch photos with merely stars in the photos. I have also searched for specialized software for this job, but I haven't found any, so I don't know if this is possible at the moment with available software. If anyone knows more about this, I would very much appreciate information about it .

Nice photos! I use Hugin to stitch panoramas (astro and otherwise), with astro pics I usually have to manually identify 'control points' for the stitching algorithm.

 

[DennisN]

Nice photos!

Thanks!

I use Hugin to stitch panoramas (astro and otherwise), with astro pics I usually have to manually identify 'control points' for the stitching algorithm.

Oh, I forgot about Hugin, if I remember correctly you suggested it before to me. I will definitely try it out in a couple of hours.

Last night I actually got a lot of good photos, including a large 360 degree panorama with stars, where I used the city skylines, beach and other things as a "base" so the stitching program could handle it. I also filmed Jupiter moving, a first time for me! I will post the best things when I am done processing (I captured about 14 GB of stuff ).

 

[Andy Resnick]

Here's a recent result of stitching- a portion of the Virgo supercluster, followed by a small 'Rogue's gallery'. Individual images were acquired over the past 3 years, each night's viewing was stacked into a 'substack'. Acquisition times on each substack are about 1 hour@ 400/2.8, ISO 1000. Three primary fields of view were then assembled from substacks after stretching, denoising, and background subtraction (the lines are artifacts produced by non-identical fields of view), the three 'superstacks' were then stitched in Hugin. Images are a bit larger than usual...

 

[davenn]

Hi and thank you very much for answer and images-it looks very interesting -is there some difference in filtering function between foil as well as silvered glass?

Lot of succes hi

Not much really. the silvered glass often has a colour filter in it so the result will be a yellow to orange appearance.
The mylar film filters tend to have a bright blue colouring

 

[bruha]

Hi, thank you for answer,
hope, today I will try solar filter, (but when I produced solar follie piece unfortunately small middle hole (from compasses) was made -do you think it is problem?
thank you and lot of succes

 

[davenn]

hope, today I will try solar filter, (but when I produced solar follie piece unfortunately small middle hole (from compasses) was made -do you think it is problem?

yes, it is a problem
You have to treat filters very carefully. Store them in a cardboard box so that nothing touches/damages the front or back sides of the filter.
This goes for mylar or glass filters.

Is your filter a glass type or mylar film type ?
if it is a glass one, use a black marker pen ( texter) to cover over the scratch

But by your comment, I'm assuming it's a mylar type. I have used a small bit of black tape over a hole/mark in an urgent situation ...
Away from home and unable to make a new filter.
Show me a photo of the filter so I can see what you are dealing with Dave

 

[bruha]

Hi and thank you for answer,
filter is Baader astrosolar safety film 5.0 and I attached photo of filter,.

 

[bruha]

Hi and thank you for answer,
filter is Baader astrosolar safety film 5.0 and I attached photo of filter,.

 

[bruha]

 

[bruha]

Thanks :):)

 

[DennisN]

Last night I actually got a lot of good photos, including a large 360 degree panorama with stars, where I used the city skylines, beach and other things as a "base" so the stitching program could handle it.

Here is the large 360° panorama (resized here to appropriate forum width) which is a combination of 25 photos, ISO 50, f/1.8, but I don't remember the exposure times which for some reason weren't saved in the photo info. There are stars in the picture, but they are only visible in the large photo versions (see photo links below).

Info (from left to right):

------- Turning Torso --------------------- Malmö ---------------------------- Øresund Bridge -- Copenhagen ---

Larger versions are here, and darker versions are here and https://www.flickr.com/photos/132956507@N08/46973326824/sizes/l.
Copenhagen was definitely observed when doing this measurement, so I think I collapsed the wavefunction of the city.

I will post a short clip of Jupiter moving in my next post, when it has been uploaded to youtube.

We have very clear skies here again today, so I will probably try some more stuff tonight! .

 

[DennisN]

Jupiter moving in my telescope:

 

[bruha]

 

[davenn]

View attachment 242856

this and your earlier post...
What are all the large discoloured patches ?

looking at my one ... maybe it's just the way the light was reflecting from "waves" in the surface ?

 

[davenn]

@bruha

" filter is Baader astrosolar safety film 5.0 and I attached photo of filter,. "

the forum is playing up, it wouldn't let me quote that textYes, the same stuff that I use
it's good stuff but as I said earlier, you need to treat it carefully

If you did get the whole sheet ... I would suggest you just redo the filter with a new piece of film

 

[davenn]

Here is the large 360° panorama (resized here to appropriate forum width) which is a combination of 25 photos, ISO 50, f/1.8, but I don't remember the exposure times which for some reason weren't saved in the photo info. There are stars in the picture, but they are only visible in the large photo versions (see photo links below).

love it ... really nice

 

[bruha]

HI davenn
and thank you for answer,,
my photo is filter but from outisde not attached to telescope. -it is not image of sun observing !
Anyway I covered this small middle hole with piece of tape and will see (if will be today sunny ), in other case I will redo it.

 

[Andy Resnick]

Got these over the weekend- the first deep sky objects of astrophotography season (for me): M51 and M101. 2 hours acquisition time on M51, 5 hours on M101 (both 400/2.8, ISO 1000-ish, both 1:1 crops). These images still need some noise reduction and color-correction...

Each full frame shows a multitude of galaxies, I'm especially fixated on NGC 5474 (image is roughly in the center).

 

[Andy Resnick]

Here's what post-processing can do, starting from the previous post: this is a 2:1 zoomed image.

 

[davenn]

NGC 5128 Centaurus A Galaxy
Canon 6D, 400mm EF L lens, ISO4000, f/5.6, 16 x 30 sec lights, 9 darks
Stacked n Sequator, edit in LR ( cropped)
This galaxy is well known for the large dark dust band across the middle of it

Dave

 

[bruha]

Hi
I attach my first image of sun.. there is one sunspot, I attach as well second image (DSC02558) as sample of error dark artefacts whose must be due some scratching or wrinkled filter … ( I have no another explanation)..
Have nice day

 

[davenn]

Hi
I attach my first image of sun.. there is one sunspot, I attach as well second image (DSC02558) as sample of error dark artefacts whose must be due some scratching or wrinkled filter … ( I have no another explanation)..
Have nice day

other than the blobs, a good sunspot capture

OK, wrinkles/waves in the filter film wouldn't produce those artifacts.
I would put money on it being dust on the lens or on the camera sensor
Note how those artifacts are out of focus, indicating that they are closer to the camera than
what you are trying to image ... ie, the sun

Can you please use another camera ( maybe your phone) and take a foto of your imaging setup,
when it is all connected up, so that it shows camera, lens/telescope etc that you are using.
cheers
Dave

 

[davenn]

Last Friday night ( 10 May) our astronomy club had a public outreach as part of the local
botanical gardens "Stars over the Gardens" night.

It was a bit of a variable night, starting nicely as the sun set and the stars started coming out.
A cool wind was blowing that made us all dress up with multiple layers of clothes as the
temperature dropped. About 30 mins after sunset some large dark clouds rolled in and dumped
a shower of rain on us all, causing a scramble for things to cover all the telescopes.

The clouds hung around or almost an hour which, sadly, really ruined the night for the majority of the
members of the public that turned up. Most left, including a few of the club members who didn't think
it was going to get any better but a hardy few astronomers and public stayed around and were treated
to an almost cloudless sky. We were able to point out the constellations and show the small crescent of
the moon and other objects through the telescopes.

As can be seen from the photos, there were a good range of telescopes to look at and through
Schmidt/Cass, Newtonian dobo mounted, and several brands and different sized refractors.

8" S/C and 10" dobo in the foreground

8" dobo in the foreground ( I used to have the same one) and 1 x 100mm and 1 x 120mm refractors
in the b.ground

View from the other direction 120mm (left) and 100mm (right) refractors

My 100mm refractor in the foreground and a 150mm refractor behind it ( both Skywatcher brand)

cheers
Dave