alacant

Hi everyone The haze held off sufficiently last night to be able to push this one a little more than usual. processing Calibration: Siril. Heavy lifting: StarTools 1.7. Niceties: DarkTable. Thanks for looking and do post if you've had a go at this with a dslr. 700d on gso203: 4 hours @ ISO800

Hi everyone An old thread I know but does anyone have CAD drawings/files for this design as above? TIA

Think where the dslr sensor was positioned when in focus with the ff. Your 533 sensor with the ff needs to be at that same distance. Now look at how far buried in the camera the dslr sensor is: 44mm. In the 533 it's only 6mm. Any good? Worse?! Cheers and HTH

Hi everyone Set for all night, alas curtailed by haze from the onshore -damp- easterlies with about 3 hours of darkness remaining:( Thanks for looking and do post your dslr examples if you've had a go at this. 700d on pn208: ISO800

Hi ATM, Mars won't appear much different from a star at magnifications available with your 150. You should though be able to discern a small disc with a short eyepiece if the atmosphere is steady. Either side of focus, you will see the spider vanes -with a black blob in the centre- as you describe. Focus on, say Capella as tight as you can. Then leave that focus position for Mars. That represents the best you'll get. Cheers and HTH

Hi everyone I managed to steal back a fast reflector. Nothing like the field of view as the 72ed last night but oh, the speed. Thanks for looking and if any dslr users have had a go at this, do post. markarian's chain (detail) 700d on es208-f3.9 3 hours ISO800

Hi everyone Easter weekend, so everyone stole borrowed the decent telescopes to image galaxies. I ended up with a miserable short refractor, Perfect for galaxy season! So, 3 1/2 hours later, it gets you to 03:00, still with 3 hours of darkness. Couldn't find anything worthwhile to fill in 3 hours, so just got EKOS to park and shut down. Of course the sensible thing to do is (would have been?) to just continue and almost certainly lose more of the noise. Didn't think of that until I awoke this morning. Very much a DUH moment. Thanks for looking and do post if you've had a go at this with a dslr. 700d @ ISO800

Hi We should be able help with -links to- a light frame, flat frame and, if you've made them yet, a dark-flat frame. Cheers

Dark current is temperature dependent. It is impossible to match light and dark sensor temperature when using a dslr; the temperature varies during the exposures. Their use will therefore add more artefacts and noise. There are dark optimisation algorithms which can be used when all else fails; usually for old sensors with banding. DSLR: take bias and flat frames and dither between the light frames. Stack with a clipping algorithm. HTH

Hi The master calibration frames do not work correctly. The bias is too bright and the flat over corrects. Not many of your frames have usable data. Recommendations: - lose the barlow - use ISO200 - use a cc - bias: 1/4000s in a dark room - flat: use a light panel with paper to adjust the exposure to over 2s with the camera on aperture priority - don't use dark frames - use Siril for calibration, registration and stacking Good luck and HTH

hi Wind gusts maybe? If you have only a few bad frames, how about stacking and then correcting the stars?

Hi Yes, but... There is much more to Siril than the scripts. I'd highly recommend pre-pocessing, registering and stacking manually, at least to begin with, otherwise you may as well just use dss (or maybe not on a mac). Move onto the scripts when you are familiar with the workings. You may just stay with manual;) Cheers and HTH

If it works for the laptop, it will for the pi. Use vnc/SSH or WHY.

Windows is not perhaps the best platform upon which to build an automated solution. There are however many alternatives. ASI and StellarMate for example offer commercial systems with inbuilt automation modules which are designed for the task. Simply connect via your 'phone and you're away. Even better, build your own. Linux does what you decide. Add to that first class security, networking and reliability... Cheers

Unless you've an ancient DSLR, lose the dark frames or take one set of dark frames and use an app which has a decent optimization algorithm e.g. Siril. HTH

Meridian flips are included in the automation process.

All our sessions are as such. If we had to sit by the mount all night, we'd soon lose interest and so obtain little data. We use the EKOS scheduler which automates the process from start to finish; over Internet on your 'phone if you're not planning on being on site. Cheers

Hi Could you please post the link/reference and the target example? AP. The dark art indeed. Until you've tried the methods available, you don't know which will afford the most pleasing result. The advantage being that you have only your own criteria by which to judge:) Cheers.

Also around the same time you have m13 and m92. Superb with your 200p:)

It means 'get your images into a state where they can be stacked'. In your case this would consist of manipulating your light frames with the bias and flat frames; best to lose the dark frames with an 800d. It's what's done inside the OSC black box you mentioned.. To get the best out of Siril, I'd recommend learning how to use it manually before using the processing scripts;) Now you do! But seriously, to do anything other than basic processing (for which you may as well just use DSS), you need to understand what's going on in the scripts. The tabs are easy to understand and there are loadsa tutorials. You could try both methods. Use a sequence with just your two stacked images > register > stack Yet another way would be to layer the two stacked images in GIMP using screen/lighten/WHY. Not a problem. Unless you've been using the HST, you'll see no difference. 16 bit output in Siril is fine. if you like Siril, you'll most probably like StarTools too. Instead of stretching using the levels and curves of the 1990s, it uses mathematical modelling to achieve a cleaner result. Your image is held linearly in a database throughout, thus obviating the need to distinguish between said and non-linear versions of the same. HTH

Method here.

Siril: use images from two nights, even if you've moved the camera. One of many ways: Pre process both nights, say folders n1, n2 but do not register and stack. Create a new folder for the combination and set it as the new working folder. Use 'Convert' to populate from the pp_ prefixed files in n1 and n2. Select the new sequence. Register Stack That's it. HTH

In our opinion, the 250p -we've an old blue tube version- is better for both ap and looking through, and yes, it focuses with a DSLR. (Not relevant here though so perhaps time to use your other thread?) Cheers

That article to which you link refers to the 200pds. Apart from hands on, you can use a search engine to verify: https://www.google.com/search?q=250pds+secondary+size&oq=250pds+secondary+size https://www.teleskop-express.de/shop/product_info.php/language/en/info/p3888_Skywatcher-Explorer-250PDS---10--f-4-7-Newton---2--1-10-Crayford.html

Hi I think the term oversized is misleading. It's the optimum size to capture all the light reflected by the primary. Too small and you lose light. Too large and you block light. 250p: 58mm 250pds; 63mm With a 58mm on a pds, check you're not losing light. Crude method: point toward the sun holding a sheet of paper at the open end of the tube. Cheers