Marmo720

Thank you for the response. Happy to know it isn't something specific to my setup - gives me hope I have attached the same data but without flats (with darks + bias), and without darks (with flats + bias), and lights only (no calibration). I do have some Ha data from tonight and will do same with that to see what the results look like. How do you overcome this issue with your camera? What settings do you use for gain, offset, ADU for flats? Thanks again!

Hi all, I have made the jump to mono with altair hypercam 1600m, combined with 36mm filters and ZWO 7 EFW. I have the train setup to the spacing given for the altair 1x flattener on my Wave 80 ED. To the best of my ability anyway... The link below shows a DSS stack of: 60 x 60 sec lumi at gain 500 50 x 60 sec darks 58 x 0.3sec bias 50 x flats at 2000 ADU All are at -15 deg. The camera is 12 bit and I thought 50% would be 2000 ADU. Equivalent to about 30K on a 16 bit camera. I have tried half the number of flats. I have tried ADU ranging from 800 to 2000. All give me very similar results to the below image. Stuck for what to do so appreciate any advice. https://we.tl/t-pA4rzIxaMb?src=dnl

As always, thanks for the advise Roland I have gone for the Altair hypercam. Hoping for clear skies!

Hey all, Hope everyone and their families are well. I am now considering going mono from my current astromod Canon 600D and would appreciate any advise and guidance. My imaging telescope is the Altair Wave 80 ED APO (with 480mm FL). I came across the sale of a set of ZWO 7nm narrowband filters (36mm) with the matching ZWO EFW for a reasonable price. Before I commit to buying that, I also wanted to check which camera to get at the same time or whether worth waiting. The 3 cameras are all around the same price used from different locations (ABS, Facebook etc). They are the Altair Hypercam 1600m, Atik Horizon and Atik 383L+. All have similar FoV with my telescope (slightly smaller than my Canon 600D) and I believe all have similar back focus, which should work with the 36mm filters. Any advise with those cameras? The 383L+ is a CCD vs the other two CMOS. If age matters, the Altair is the newest and I am not sure how old the other two are yet. The other alternative is to wait for the ZWO 1600mm Pro to be on sale (or used) and get that then. Would mean the smaller filters would be cheaper too in the long run. For reference, I am imaging from Bortle 8 skies. Thanks in advance for any advise

I have very similar scope and guidescope setup to you @oymd and the dew straps and controllers I linked to in your Wanted thread are the ones I use. Work very well and I forget they are there when imaging. I got the quad channel just in case as the price difference was minimal. I was also in same boat as you in terms of getting a controller or not but considering how cheap they are and that it can always be sold on if required meant I just got a controller anyway. Make sure you read the small instructions that come with them and they are very easy to use. The straps come with long durable leads and so can be moved to the side and away from other cables.

Thank you. Glad 4GB at least works for long exposure imaging. At the moment the price of n4100 mini pc with 4GB ram is about same as raspberry pi 4 4GB once everything is bought so not saving anything long term besides time! I did consider that a windows mini pc could always have a Linux distribution installed if I wanted to do ekos etc route.

Thank you very much for getting back to me. I am relatively comfortable with Linux and command lines (use some python at work) so can figure things out but I also don't want to spend heaps of time trying to figure it all out when my Windows setup works fine. Is the Zotac the 4GB or 8GB ram? I am concerned if 4GB is too low or not future proof enough or am I over thinking it? I am mainly focused on DSO imaging but will want to do planetary when the opportunity comes. Thanks again.

Posted multiple times for some reason - sorry!

Posted multiple times for some reason - sorry!

Hi - how did the Raspberry Pi 4 setup work? Was it stable and how does it compare to your mini pc experience? I have been considering either option for about a month now as my current laptop is high end gaming rig that I don't want to wreck. Last night was so cold that I could barely stay out long enough to get everything setup, which can take half hour if I don't need to do focusing!! Can you advise on your experience with both as I am ready to pull trigger on either Raspberry Pi 4 or with Beelink S2 that has N4100 processor and 4 GB ram (I was hoping for 8gb Ram but can't see that model in the UK). Thanks, Marmo

I am going on Saturday and would be great to meet forum members. I am meeting Carole there too and plan to spend on a few things for my astro imaging setup. Will be my first astro event so excited to see everything

Just to update on this - it seems my issues with the imaging train and flats are fixed and I can finally do some astrophotography!! I spent all of Friday night capturing the Rosette Nebula and I was able to get nice tracking for 3 mins and then 4 mins. My only attempt at 5 mins shows some star trails but didn't want to spend the cold night trying to fix that. The attached is auto save from DSS with 45 mins at 3 min subs and 40 mins at 4 min subs. I didn't need darks it seems either so only used lights, flats and bias. Flats I had to do manual instead of the auto setting on APT. Unfortunately, the rest of the nights imaging and also Saturday night are wasted as dew covered my lens and guidescope lens too so will be buying dew heaters at the Astrofest in 2 weeks. Just wanted to say thanks to everyone who gave advise and helped with this. Excited to do some more imaging!! Thanks @RolandKol and @carastro for showing me what a processed image looks like too so I can practice on this data while the skies are cloudy. Clear skies all. Autosave_NGC2237.tif

Thanks for the advise. I have been dithering for a couple of months but continued to do darks anyway as I didn't want lack of them to be reason for why I kept having issues with my stacked images. Now that flats issue is fixed, I will try experiment stacks with and without darks. If there is no difference, then I can save myself time or use the time for lights if clouds are clear.

Ah - thanks for the clarification. I haven't kept an eye on temperature as I always do flats on the same sessions anyway. However, I have noticed for example winter temperatures are about 18C while summer is obviously higher so can't use same flats. Since I do all my darks at the end (and normally after bias and flats), if the temperature has changed a few degress, it should be fine? Or should I be taking darks straight after lights to be as close as possible in temperature and then take flats/bias last? Thanks, Mo

Good tip on darks I didn't realise you could keep darks for a few months like you can with Bias frames? My flats are relatively quick so I take them at the end of the session. However, I have had so many issues with flats since the summer that I have had to setup several times with the aim of just testing flats and no imaging. Think I am almost there though with getting the issues resolved.

I suppose that is an advantage to having an observatory in this country with all the clouds. I don't currently have one and the thought of going out on a cloudy cold night to set everything up and only image darks and flats is not appealing at all! I don't mind if I have a few hours of clear sky to collect lights and then do flats/darks once the clouds come in on the same evening.

Would another piece of acrylic work? With potentially fewer papers if needed to further diffuse? Then you can stick both acrylic together (super glue the edges?) And have less to manage every time you need to take flats?

Thanks Roland! Getting closer with every clear sky It is similar dust bunny to last one and not sure if on sensor or CLS filter but either should be easy to remove now as done it before. @carastro, thanks for the video. Will practice on my old images while waiting for clear skies.

I am using Gimp as I can quickly check the images. I also have Photoshop CS2 to see how I get on with Photoshop but not used it before. Rosette is a good idea and I considered it last night but as I only had a short time to test, I went for M31. Now that things are working again, I will commit to one target and try get as long exposure as possible. Rosette is also in a good spot for me in the sky right now. Thanks Edit: Now that everything is working well - the clouds have decided to take over. No clear skies for over a week and half according to Yr

Thank you very much @carastro! So glad to see the manual flats working and I also don't have that darkening of the bottom right that I have seen in previous images. I knew that dust bunny wasn't going to be removed by the flats as it was very dark even in single lights. I will clean it off the lens at the next opportunity but now everything seems in order for me to start imaging properly I noticed that with your CLS filter on, the 60sec was about 1/6 of the way to the left in the histograms so I know I can do longer exposures. Without your filter, the 60sec histogram was pretty much in the middle or slightly to the right. Looking forward to seeing what 5min exposures with total >2h integration looks like! Quick question - so I know the longer single subs are very useful for targets without cores but what would be the suggestion for bright targets with cores such as M31/M42? 5min subs for the fainter outer parts and shorter subs for the core? Using same ISO or do people change that depending on target brightness? Just checking as I am practising on M31 and don't want to waste any nights by not imaging correctly. Thanks, Mo

Seems to have worked! I only had just over an hour last night to get everything setup, polar aligned and image so went with M31. There is a deep dust bunny which I could have cleared but didn't have time and wanted to check if flats would work on such a dark bunny. I took these images with your cls filter Carole and didn't have time to do without filter but it is setup for next time. I took the chance to take 60sec and 180sec subs. I think I can go for 300 seconds next time with your cls filter! I also had issue that my neighbor forgot to turn off the garden security light so it kept coming on hence why top left corner looks brighter once stacked. I didn't have any of the bottom right vignette that I kept seeing in all my previous images. Here are the calibration files: https://we.tl/t-IIhgwbAvqm?src=dnl Lights: https://we.tl/t-mpw3PPaTSA?src=dnl Thanks, Mo

Thanks Carole! Lovely home and nice seeing your setup. I got all the gear setup now and just waiting for that clear night to test it all

Lovely images. I would love to borrow your CLS filter as I have seen a few on sale here and on ABS and would be good to know if it works or if I need to look elsewhere. So glad the flats look better and thank you for the manual advise. Excited for the next clear night

Thank you Carole - very happy to see the results. I could tell straight away that doing the flats manually was better as the dust bunnies stay in same place. I am guiding but I assumed anything longer than 60 secs at our locations would result in higher noise and not much signal gain? You recommended going up to 300 sec at iso 800 even at our locations and on a dslr? I guess I could do trial run on next clear night with 180sec and 300 sec.

Happy new year all. Hope you all have good health and clear skies. I took some flats last night which are linked to below. I don't have any matching lights, darks or bias so I have attached selection from different night. The camera was moved several times in between and so o wouldn't expect a nice image. Just checking if the flats are done correctly. I started with automatic plan that I have used in the past where the exposure is calculated by the camera/APT. The dust bunnies jump around a lot as previously observed by @vlaiv. I then did 2 sets of manual exposure settings as suggested by @carastro and the dust bunnies don't move around as much/at all which was good to see. I did one manual with same exposure as the automatic so they can be checked side by side and also one at 1/100s so I can reach 75% on the histogram. Any advise and help is much appreciated. Lights, darks and bias from same night but different to flats date: https://we.tl/t-Fkdf2TYAId?src=dnl Automatic flats produced by APT plan: https://we.tl/t-xr6A1hoQIQ?src=dnl Manual flat plan at 1/160, which is same exposure length as the automatic plan: https://we.tl/t-0AF8llWMZd?src=dnl Manual flat plan at 1/100, which puts histogram at close to 75%: https://we.tl/t-SQYlCTBRSe?src=dnl Thanks, Mo