alacant

Thanks. Yeah, that's an old version so the windows version is a few releases behind. Just trying to get on the same song sheet. OK. So the latest windows version is here. Unzip and find siril.exe in the bin folder. HTH

@bottletopburly Are you on windows? I'm on linux. Could you confirm that the latest windows version looks like my screenshot? Cheers

Hi Please work with the latest version of Siril. No installation necessary. The file you need is here. Then simply click siril.exe from the installation folder.

Hi Excellent effort. Well done. I found that the 450 responds well to dark frames only if you use calibration which includes a dark optimization algorithm. siril's optimisation works well to reduce noise and banding. Just remember that for the optimization to work, you'll need to subtract the bias from the dark frames before creating a master dark. Take around 50 bias frames at 1/4000s in the dark and stack them to produce a master bias. Take dark frames at the same exposure as the light frames. I'd also recommend taking flat frames. These will improve your image a lot. The image looks fine except that the background is really dark; the galaxy lost a lot of fainter stuff. HTH.

No, no, you are quite correct. In Spain, the government have included astronomy as part of the lock-down. This is reinforced at new moon with extra dense cloud cover, mist and drizzle. Notice how the waning moon gets bigger too.

In the orientation you have, the secondary needs lowering while the top edge is rotated toward you.

Siril's display window has 4 tabs. Above the image you'll see red green blue RGB. Choose RGB.

No. No. Summary: Sequence bias: Stack the bias. Sequence flat: Subtract the bias master from the flat sequence. Stack the now calibrated flats. Sequence light: choose the master bias and the master flat along with your light frame sequence. NOW choose debayer. Resultant sequence: register then stack. HTH **You have an old version of Siril. I'd recommend upgrading to the latest.

Siril works with .fits. DON'T convert. Leave it as .fits.

Hi. Check the debayer box, here:

Good. So It's working. Oh, and f6 is very forgiving anyway:) Difficult to visualise. Probably best to send one shot through the collimation cap and then another with the sight tube. Try to keep the 'phone central.

Phew. A hex key makes it that much more difficult. What telescope is it? Hex head m4 screws work fine as adjusters in most spiders.

Correct. You placed the card baffles and background to prevent seeing this and misleading yourself. 2 choices: 1. Call that good enough and go and adjust the primary. Or 2. Make sure the big hammer is still well hidden. Then... Get the cross hair intersection in the centre of the primary spot. That should be close. Look only at the primary donut and the cross-hairs. Proceed first slackening one secondary screw and tightening another. Make tiny movements. Hopefully, you'll have thumb adjusters on your secondary. If not, fit them now. Keep doing this until the cross-hairs coincide. If you mess this up, back to the baffles and start again. Cheers

If it is a combination type (tube and crosshairs) then for me, yes. I've never used anything else. The collimation myths saved me loadsa time;) Cheers

Hi autodev - crop - bin - wipe - autodev - hdr reveal core - decon - colour - entropy Ha - denoise Issues: walking coloured pixels. lose the dark frames take light, bias and flat frames. dither between each light frame. stack using a clip algorithm I then made it look a bit better (with the discalaimer that I'm hopeless with colour!) HTH

Hi Do you have a Cheshire sight tube with cross hairs? Do exactly as you do with your other Newtonian. The only difference you'll see is a greater (at first quite alarming) secondary offset. Cheers.

LOL, yeah. I don't think I'm allowed to say 'magnification' on this forum but 1200mm is the closest I can get:(

Hi everyone <self-pity> Lock-down day thirty -I've-lost-count- something with only 3 clear nights since it started. Desperate times in many ways. </self-pity> I looked out at 04:00 and saw a star. As the 6" f8 already had the camera+oag attached, I put it on the mount and managed a whopping two frames before the next weather front rolled in. Six minutes in all. Couldn't get anywhere with GIMP so took the easy way out and StarTools managed to rescue something from nothing. I even think the colour is somewhere close. Thanks for looking and stay safe. 700d on nt150l @ ISO800

Upload the file to e.g. Google drive or Dropbox and tell us where it is. HTH

Hi Light and dark frames alone won't hack it I'm afraid. Anyway... I'm with @spillage on the first AutoDev and the a crop to remove the stacking defects. But I'd then call wipe followed by a second AutoDev. It's the latter where you can really remove the rubbish, especially the ignore fine detail and gamma adjustments. Post a -link to- your image if you like, then we maybe able to offer specific help with this particular dataset. Cheers

Hi I think in DSS it will take the pattern from the cr2 so you shouldn't have to do anything. I'm trying to ascertain the origin of the grid pattern. IIRC, AHD does a better job than the bilinear default. Maybe try that with the same frames? IMHO and with the impossibility to be able to temperature match dark frames with the light frames, they introduce more noise. Make a master bias from say 50 frames. Subtract this from both the light and flat frames. Make a master flat by stacking the bias calibrated flat frames. Now divide each light with the master flat and debayer the result. Register and stack using sigma clip. A few minutes in Siril (method here). I gave up on dss some time ago;) HTH

Very wise LOL!

Short answer: for a Dobsonian you're only going to look through, no. Longer? The adjustments you make the second time around are tiny. The secondary mirror is just a flat bit of glass. It has no optical properties apart from reflection. The first time you use a Cheshire with cross-hairs for the secondary may take several hours, during which you may feel like taking a big hammer to destroy the whole telescope (sic). The second time takes less than 2 minutes and you then wonder what all the fuss and frustration was about. Get it close -or spot on if you like- and then stop fiddling with it. But hey, make sure you get the primary as perfect as you can. That's the easy bit anyway. Just my €0.02 but hoping it may save you some time.

Hi Nice shot. JTOL. Was the bayer pattern set RGGB? There is very little red and there is a 'grid' pattern on the original. One tip: lose any dark frames. Stick to light, bias and flat but dither a few pixels between light frames. Stack using a clip algorithm. I think dss has sigma clipping. I'm hopeless on colour but had a go anyway and fixed a few of the stars. But to repeat, excellent effort:) Cheers

Hi. StarTools will do what you want without having to jump through hoops. Siril will stack and process start to finish: you can lose DSS. DarkTable will make it all look good. If you want 90's style menus-along-the-top though, you'll have to look elsewhere. HTH