matthasboldlygone

A couple of nights ago, mist, fog and dew rolled in shortly after.. but probably the sharpest stars I've photographed so far

12 hours ago, Budgie1 said:

The focal length of the Evostar 100ED with the Skywatcher field flattener attached is 900 x 0.85 = 765mm.

What I've done is; I set the focus outside without the field flattener on, so 900mm, and when I came in after imaging I drew a line with a Sharpie on the focus tube where it meets the housing. Then I did the same with the field flattener attached. So I now have two lines on the tube and I know roughly where focus will be without having to measure each time.  

I've got various scribbles on the focus tube now  

So when you put the reducer on did you have to wind the focus tube inwards by 135mm? 

765mm from front lens to the reducer, then 55mm to the sensor?

I tried some daytime focusing, but only had a tree about 50 meters away as a target, and this didn't seem to match focus on stars.

I like to have my telescope roughly focussed before going outside, otherwise I spend hours winding the focus in and out all the way trying to find the right position.

Without the reducer I know the camera sensor needs to be 900mm from the front lens, I can measure this and then tweak it when outside in the dark.

If I add the 0.85 reducer I know the camera sensor needs to be 55mm behind the reducer, but not sure how far out or in the focus tube should be. Will it be 900mm to the reducer or 900mm to the sensor or 900mm x 0.85 ?

👍

Been busy collecting things, the good(ish), the bad and the damn right ugly

Telescope : Bresser AR 102/600 Achromatic
Camera : Bresser HD Deep Sky Camera
Mount : HEQ5 Pro
Processing : Siril / Pixinsight
Bortle : 4 - 5

The Moon
Dumbbell Nebula – M27 / NGC 6853
Andromeda Galaxy – M31 / NGC 224
Star Cluster – M92 / NGC 6341
Fireworks Galaxy – C12 / NGC 6946
Bode’s Galaxy – M81 / NGC 3031
Great Cluster – M13 / NGC 6205
Pinwheel Galaxy – M101 / NGC 5457
Triangulum Galaxy – M33 / NGC 598
Superman Galaxy – C44 / NGC 7479
Ring Nebula – M57 / NGC 6720
Bubble Nebula – C11 / NGC 7635
Iris Nebula – C4 / NGC 7823
Whirlpool Galaxy – M51 / NGC 5194
Small Cluster – NGC 6229
Deerlick Group – C30 / NGC 7331
Mars
Saturn
Jupiter
 

11 hours ago, MarkAR said:

Very nice, lovely little target.

Thanks Mark, I'd really love to do it justice but not sure my setup will be up to it. Still trying to work out if the fuzzy stars is bad focus or oversampled at 0.66" / pixel, so many variables to this hobby.

My first try at guiding with AsiAir and a new scope. Camera not well matched so think I'm well beyond the limits, but wanted to try things out while I wait for a new camera. Soft focus style

Skywatcher 100ed - Bressher HD camera - Asiair guided - 60 x 3 minutes - Siril stack - Pixinsight fiddle

This is probably my last image from my Bresser achromat with clunky focus, upgraded to a skywatcher evostar with guiding. It's been fun but looking forward to trying the new kit soon. Think I've probably pushed my current setup to and beyond its limits.

2 hours at 2 minutes (was 3 hours but lost 1/3 to star trails and focus slip) - Bresser AR 102/600 - Bresser HD Camera - HEQ5 Pro - No guiding

Been trying PixInsight for a few weeks and thought I'd go back to my first images way back at the end of July 2020 and see what extra detail I could get out of them. Wasn't very hopeful, only had 50 x 2 minutes of very blue subs.

Using some basic stretching, background removal, deconvulation, star masks and other random bits. Certainly improved my images greatly. 👍

30 July 2020

11 September 2020

Thought I'd try another not so easy target. The colour my camera was catching was all over the place, I gave up and just used the Green channel. Managed to get 3 hours but lost an hour to clouds.

60 x 2 min - Bresser AR 102/600 - Bresser HD Camera - Siril and Pixinsight

Always thought these looked a bit boring, but I'm growing to love them. Spent about 30 minutes on each one with 30 second exposures, happy with the way it all turned out.

Bresser AR 102/600 - Bresser HD Camera - Siril stack - Pix insight fiddle

M13

M92

NGC6229

Bonus snap - M81 Bodes Galaxy 

Productive night

First night - missed the target and took lots of images of some nearby stars
Second night - 35 x 2 min
Third night - 60 x 2 min

I've tried stacking the two nights separately and all together to give a total of 3 hours, but the stacked images all turn out roughly same. Think I must be limited somewhere else and the extra data isn't being captured. The best of the batch was a very quick process of night 3, 2 hours. I was happy to see the bubble shape and a bit of cloudy bits 👍

Bresser AR 102/600 - Bresser HD camera - Stacked in Siril, simple process in Pixinsight

On 23/08/2020 at 14:30, Adreneline said:

Nice image - really well framed. I think the first one is the best of the bunch.

You can reduce the star colour fringes using a Noise filter:

You might want to experiment with the Reduce Colour Noise slider. Works better on some images than others.

Adrian

P.S. Apologies if you already know this trick.

 

Thanks, I've been playing with noise filters, like you say seems to work better sometimes than others. Much more to learn about noise in general 👍

It was a dark and stormy night ... but between the rain, mist and 50mph winds I managed to get out and grab this. Surprised how bright this nebula is, easy to find on short exposures, 30 x 1 minute and a few darks. I'll try it with a barlow next time to see if I can get it a bit bigger without the drizzle in Siril

Bresser AR 102/600 - HEQ5 Pro Rowan - Bresser HD camera - Siril and Photoshop

Not sure if you're wanting to call a 3rd party API or acquire a dataset for your own use? If you just want the data you could webscrape it off astronomy.tools (assuming it's for personal use) , it's all in the HTML source. Doesn't look like they have an API as such, just a bit of jquery and some drop downs. 

I doubt anyone would want you calling their API unless it's setup for public use. There's a project for you...

Between the clouds I managed to get 1 hour of 1 minute exposures on my new target. Stacked 70% of them in Siril and Pixinsight, used Pixinsight for some background removal and finished up in Photoshop.

Bresser AR 102/600 - Bresser HD Camera (sony imx290) - Siril, Pixinsight, Photoshop

It's a bit bigger than I thought it was going to be. I'll give it a few more sessions to see what I can drag out of it, but quite happy with my short session last night. I guess a couple of hours in total time is considered an 'instant photo' in this game

After a couple of weeks and 3 or 4 good sessions outside I think it's time to move on from M27. Must have processed, stacked and stretched the images a 100 times now in a combination of Siril, Pixinsight and Photoshop. Various image sets from 30 seconds to 1 minute taken on multiple nights. Probably 1.5 hours used on these images.

Bresser AR 102/600 - Bresser HD Camera (sony imx290) - Siril, Pixinsight, Photoshop
30sec - 1min + a few darks

Quite like this one but the star is big..

A nice apple core floating in space

And maybe the best I could get at the moment with the help of Pixinsight (not that Pixinsight is very 'helpful' , bizarre software design)

Looking forward to getting a guide camera and being able to take longer exposures without trailing stars.

For now time to find something new

Thanks @michael8554, I will do some playing and time the movement more accurately. I'll also watch the belt / gears to see if anything looks odd. Sounds like guiding is going to be the way forward.  

I've always noticed some star movement, not drift as in a bad polar alignment. It's a back and forth movement over 10-15 minutes.

The Rowan belt was installed by FLO, level tripod, good polar align, light and balanced payload.

This is two exposures to show to extreme movement. The most I could get was 30 second exposures before star trails got really bad.

It seems to be worse with the scope in certain positions, pointing low East isn't too bad, but this pointing South and higher in the sky.

I've looked at programming periodic error on the handset but that looks like it could take maybe 1 hour every single time I use the mount. That would probably be the end of it for me, there's enough setting up without adding that level of hassle.

I'm sure a HEQ5 Pro with Rowan should do much better than this, I hear of other people doing 5 minute exposures without guiding.

Any suggestions?

That's a great start, looks much cleaner than my first attempts. Looking forward to seeing your progress on it. What equipment and software are you using?

2 hours ago, MarkAR said:

Lovely image, that's the closest view of the Dumbbell I've seen. What equipment are you using?

Thanks Mark, I did a bit of cropping and resizing in Photoshop to get a nice fit.

Bresser AR 102/600 telescope
Bresser HD Deep Sky Camera (Sony IMX290)
HEQ5 Pro + Rowan mod

110 x 30 second exposures - gain 15 / 50
Stacked in Siril, played with in Photoshop including some enlargement

Picked up some good tips and advice here and thought I'd give a nebula a go. Really happy with this one. Had to use 30 second exposures due to movement in the mount, annoying, but it worked ok. Maybe 45 minutes in total. Seems to be a more friendly target 🤗 

Bresser AR 102/600 telescope
Bresser HD Deep Sky Camera (Sony IMX290)
HEQ5 Pro + Rowan mod

110 x 30 second exposures - gain 15 / 50
Stacked in Siril, played with in Photoshop including some enlargement

On 11/08/2020 at 13:51, ollypenrice said:

The final image had about 30 hours total exposure in Ha LRGB. 

Great images, 2 hours vs 30 hours, I can see I definitely need to increase the total time somewhat. A couple of hours isn't going to get what I want. 👍

On 11/08/2020 at 12:39, vlaiv said:

here is comparison image:

 

I'd be happy with that one. I can see my expectations of 1-2 hours are too high, tried stacking everything I've collected so far, maybe 3 hours and it's getting there in a way. 

1 hour ago, Hallingskies said:

Try your imaging rig out on a few less demanding targets (e.g. M81/82, M42, M27, M13) and see what your results are like before spiralling into the never-ending cycle of kit upgrades...

Good advice, I'd like to max out what's possible with what I have before going further. 

I've been trying a few 5 minute exposures but getting stretched stars, periodic error maybe? I was thinking a good upgrade would be a guide scope / camera to get those nice long exposures.

1 hour ago, michael8554 said:

What do YOU think is lacking in your images ?

I felt it was a little hazy and fuzzy. I'd like a bit more detail / contrast in the cloudy stuff, and a few more of the bright stars in the structure to pop out. But after looking at some other examples I can see they all suffer a bit from those issues. 

Maybe I'll give M81 a go next time, or find another target a bit higher in the sky. Choosing the right target at the right time is something I need to think more about.