matt_baker

Gone at it again. Forgot that with canon banding you have to rotate the image 90 degrees before applying the reduction. Went for a more subtle approach and made sure DBE was correct unlike last time

Also seems to be an artefact that didn't get corrected by my flats toward the bottom left. I exposed for almost half well depth and that ended up being about 75% of the histogram, so I'm not sure if the flats were too bright to pick up the dust?

Here's my first light with my new modded 600D on the Elephants Trunk Nebula.

I took 22x600s @ 1600ISO with a Duo Narrowband filter.

I decided not to take any darks as this would waste heaps of time, and just decided to dither at 5 on APT but I can still see some questionable banding? I took flats and used my superbias as a master dark.

I definitely need more data as it's very noisy but at least it's a start and when it's next clear I can take more subs. Is 10 minutes too long especially for a non cooled DSLR?

Also what's the best way to mitigate the red stars?

1 hour ago, ollypenrice said:

You could just get a length of square section steel tube (probably an offcut from a local metal yard) drill it and bolt it to your dovetail and then bolt your tube rings to the opposite side of the steel. The steel between the dovetail and the scope will put the scope further from the saddle plate, considerably increasing its moment.

Olly

I like the idea, unfortunately I don't have access to a drill that'll do the job, only my dad's knackered 20 year old Bosch

1 hour ago, Peter Drew said:

Try it without a counterweight.      🙂

I did but the scope was way too heavy

I've ordered the tube rings that'll arrive on Monday hopefully and I'll see if that'll do the trick. My telescope weighs 4kg, the ST102 is about 3kg, camera is ~700g with coma corrector, and the tube rings for the 102 are about 500g, so all in all, it brings the total closer to 10kg

I do have some weights but unfortunately the bore diameter is 1 inch, not 1.25

So this will seem very overkill but I mounted my 130PDS on my local obsy CGE mount.

Now with everything attached and the 10kg counterweight pushed all the way up, it's still way too heavy.

I do have one idea to counteract this and it's to use a spare 102mm refractor and stick it on top as a beefy guidescope and to add extra weight.

I don't really want to spend £60 on a 5kg weight that's for the G11 but the hole diameter on the CW is 1.25 inch

Any ideas?

https://www.amazon.co.uk/gp/product/B07GSVB7RR/ref=crt_ewc_title_oth_1?ie=UTF8&psc=1&smid=ANIKFWVM7JXQP 

Think this is it

Looks great! 

Was wondering if you could upload the masters, so I can play around with my processing?

On 26/04/2020 at 21:00, Pete Presland said:

Looks pretty good to me. I can see the stitch lines slightly, what program are stitching with?

On second thoughts, I don't think what you're seeing are stitching artefacts.

I have a feeling they're horizontal banding artefacts?

11 hours ago, Merlin66 said:

Matt,

The download link didn't work for me, but I found the site:

https://ft.rognemedia.no/

I'm not sure how effective this process is on solar images which only show "some" NR - not extending across the whole image.

Worth experimenting with????

(AstroArt also has a FFT filter, but it didn't work too well for me. I asked Fabio, and he said it (the FFT filter) only works where the fringes extend across the whole image. Bumma!)

 

Sorry, I messed up spelling of the URL, has been changed now.

My NR actually didn't extend across the whole image, only certain bits of it, should've made it a tad more clear

On 21/04/2020 at 09:06, Uranium235 said:

FYI, the lightbox I used was this - 14 quid from amazon:

I then created a protective cover and OTA attachment using the box it came in, and a bit of foam oh, plus 3 sheets of A4 to further dim and diffuse the light. The pic shown is with it on max brighness, I've only used the lowest setting so far on lum data. NB will probably require it to be kicked up a notch or two in brightness. Its amazing what you can do with a bit of glue and tape  

Probably needs a bit more tape around the edges, just to make it star party friendly.

 

Do you have a before and after comparison with your flats? I'm considering doing this based on your idea and it looks cheap and effective, without spending £200 on a flatbox.

Would rather spend that money on going towards a mono cam rather than that

13 hours ago, Merlin66 said:

Matt,

When you say you used PS......was that the Photomerge option? (file/automate/photomerge)

I found ICE and other programs didn't work too well for me, but that Photomerge did a pretty good job.

 

For some reason photomerge didn't like to align it so well so I loaded the files into a stack, told it to automatically align, and aligned the 2 mismatched panels myself then blended that to create the image

That'll only stitch JPEG's, I need to be able to do tiff files

Photoshop, as ICE will only do half of it for some reason

35 minutes ago, MarkAR said:

Looks really good to me, well done.

Thanks, Mark!

Went out again today and got this. Is there anything I could improve on? 

Drizzled and re-edited

Just found out how to suppress newton rings in a Ha Solar image and thought I'd share with you how

I tend to do this after all of my sharpening but you can do it before

I'm not sure about all the maths behind Fourier Transform but I know what to do

1. Download http://www.rognemedia.no/diverse/FFT.zip (It's an instant download)

2. Extract all but the .dll file into a folder in Plug-ins on Photoshop (typically located C:\Program Files (x86)\Adobe\Adobe Photoshop\Plug-ins) and call the folder FFT

3. Place the .dll file into the root directory of Photoshop

4. Load up Photoshop and change your colour to RGB using Image > Mode > RGB

5. Go to Filter > RONC 2018 > Ft2DH

It should do it's thing and come up with something like this

Now depending on how apparent your NR are, will depend on how easy they will be to see and suppress.

Mine aren't so apparent, so you have to look carefully for a bright speckle(s) around the star itself

In my case, although very hard to see are two brighter spots in the image

6. Paint over them in solid black with about the same diameter brush like this

7. Go back to Filter > RONC 2018 > Ft2DH and click on iFt2DH

8. Now hopefully your NR's are much less apparent or eliminated

Here's my before and after on my NR's:

Before:

After:

Hope this helps anyone

2 hours ago, Davey-T said:

Could be Newton rings.

Dave

I think you are correct. Although I wonder why I only get them on some of the panels and not others?

This is my second attempt at a mosaic with the LS60 and QHY5L-II M with a 2x Barlow.

I'm using sharpcap and sometimes although not as bad as last time, I got weird diagonal lines appearing and I'm not too sure why. They are faint in the raw AVI so it's hard to see them unless you squint but when you stretch the image out, on my first attempt, they were very prevalent.

Other than that, it went well, apart from a bad panel on the middle right, which is a little blurry.

Here's the processed version, still some funky stars but they appeared in the raw stacked image so I'm not sure

I figured out the issue. Apparently it didn't like being in 16 bit so I set it to 32 bit and it just worked. vlaiv was right

2 minutes ago, vlaiv said:

I have no idea but suspect low bit count of data.

Did you by any chance take PNG file that was posted online and is only 8 bit per pixel? That could explain artifact.

Maybe convert it to 32bit float prior to DBE?

It's a 16 bit fits file

I've been processing someone's data but I noticed that whenever I tried to do any kind of DBE, I would always get these wave like structures and can't get rid of them.

Does anyone know what's up here?

Complete re process of M45 that I took in January 

Maybe the noise in the background is a little much still? But I'm sure this could be fixed next time I image this.

What would be the best way to go about PEC Training a CGE with a C14 mounted onto it?

I remember trying to guide with a 50mm guidescope (not ideal I know) and the DEC guiding was awful but RA was okay after calibration.

Is this something PEC can fix or is there something else at bay here that needs fixing with the DEC?