Recently Browsing 0 members
No registered users viewing this page.
Still sorting the (new to me), Atik 16200 imaging train as I try to shift from my trusty SBIG 8300, Mac to PC for mount control/capture and from a separate guide scope to the Atik OAG....
The camera needs to go back to Atik (awaiting the email from Vince) as there is dust inside the chamber, so this is a good time to get everything checked - ready for the autumn season.
After some imaging/testing time at the rear of Leo in the last week, I noticed on my flat frames a strange half moon light - by the dust mote (that was over-correcting the lights).
Eventually I worked out it was the screws surrounding the sensor cover window (or the 3x rounded cap screws that attach the EFW3), bouncing the light onto the back of the filter (Baader L in this example) and I suppose onto the cover window and onto the sensor. To test the theory, I opened the imaging train up and added a Sharpie pen to them. Couldn't get into the cross-heads with the pen, but with re-testing, the reflection had gone! Perhaps it would never be an issue with the actual light frames, but you never know with a bright star in the frame of a future target...?
So today, after shifting slightly outwards the OAG stalk, I addressed the stainless steel screws 'properly', by (again), taking everything apart and lightly painting a cover of matt black acrylic paint over them and into the x-heads (a bit of overspill), nothing too heavy-handed as I didn't want to glue the things in with paint! The finished effect is duller than the pic here and the reflection has gone after another round of testing.
Always something to catch us out, hey!? Why Atik can't use black screws is another matter.....
Perhaps this may help others out at some stage....
when applying the flats taken in my last session (to find out what is causing the strange diffraction spikes) with Siril, the final stacked result still shows the vignetting and the dust spots. I also did the whole preprocessing with Nebulosity, same result.
I took the flats as follows:
same iso as my subs camera and focus not touched I use a homemade flatbox combined with the a white t-shirt with Ekos took test shots till the histogram was half-way to the left checked all my flats, they all show vignetting and the same dust spots as in my subs I tried using them with and without using a bias frame, same result, the final result looks as if no flats were used.
Anybody any idea what is going on? An other question I have, will the vignetting and dust spots also show in the master flat (flats stacked)?
Thanks for your help,
I have a huge problem with DSS.
About a week ago, I took 300, 2 second long exposures of Andromeda with my skywatcher 90/900.
But when DSS started scanning the stars in the images, it only registered about 5 stars at 40%. And only 7 stars at 20%. I tried to stack them and selected stack 100% of frames, but it only stacked around 29.
I even tried it at 4% where it registered around 40 stars, but DSS crashed mid process due to the immense amount of stars being scanned (60 000 per image at least).
I tried it sooooo many times, but I don't get it to work. It somehow stacked 131 images I took of the lagune nebula (1 second lang exposure). You couldn't see the actual nebula, but some bright stars were there and DSS was able to stack.
In the Andromeda pics, there were like 5 times more stars, but it didn't work.
If anyone knows what's wrong, pls help me!!! I'm slowly loosing it on that nonsense.
I'm trying to stack 240 light frames of Milky Way taken from quite a light polluted area.
I tried to stack them in DSS. The Milky Way seems to have been stacked okay, but the surrounding stars look like they've been deliberately dimmed or brushed over.
I thought there was something wrong with my frames but when I used the same frames in Sequator, it's working fine.
I've attached both the images below, and I have exaggerated them a lot on Lightroom just to see how much details I could pull out. Sequator one seems to have too many weird light bands(?) but I think I can fix them using an adjustment brush. But look at how many stars Sequator is able to show compared to DSS.
DSS image: The settings I've tried on DSS and yet nothing changed:
1) Tried in Standard, Mosaic both
2) Tried both Sigma Clipping, and Auto Adaptive Average(These two were recommended by DSS)
3) Hot pixel detection and removal (tried it with enabled and disabled)
4) Nothing enabled in the cosmetics tab
5) Tried with and without Flat frames
6) Star Detection Threshold: Tried from a range of 50 stars to 300 stars. Even manually checked to see if DSS was picking any noise as star(it wasn't).
If I try with less than 30 light frames, DSS does an okayish job and the stars in the rest of the image still look like stars, but then the Milky Way has no details to pull out, unless I stack a lot more shots.
Can anyone please tell me what am I doing wrong in the case of DSS that it's doing such a poor job for the surrounding stars? If you guys need me to upload some Raw light frames I will do so as well. Any advice and suggestions are welcome. Thank you
Camera: Nikon D3100, with 18-55mm kit lens
Exposure Settings: F/3.5, ISO 3200, 15s x 240 frames, 18mm focal length, no tracker
50 Darks, 50 Bias and 50 Flat frames.
DSS version: 4.2.3
I've created my own darks library for my ASI1600mm Pro. Various gains and various exposure times all at -10 Celsius.
I'm just wondering what people do with them? Once you've taken darks and processed an image you get your master darks.
Do you guys just keep the master dark, in a master darks library, or do you process your darks again each time you stack a new image?
I'm just thinking to save storage, could I discard the dark sub frames and just keep the masters? I don't want to throw them away if that is wrong though.
Also, with this camera I take dark flats rather than bias frames. Because the scope is covered, do I need to do dark flats each time I take flats?
I have an even illuminated flat box which I always use at the same exposure lengths. I guess the only thing that could vary is the gain value.
I understand the need for flats every time you change focus, for each filter etc., but if I'm using the same exposure time can I just use a previous set of dark flats as long as the camera settings are the same?
If this is possible, can I then create a dark flats library for any difference in gain values? Not sure if I gain values affect dark flats though.
I've read that back, and that's a lot of questions! All help greatly received.