Adreneline

Hi. I was in a very similar position to you three years ago (ED80 + Canon 70D) experiencing exactly the same feelings with what I considered to be disappointing images (except Andromeda which looked great!). Modding the 70D was never going to be an option for me; I also use the 70D a lot for everyday photography and really didn't like finding it covered in dew after a night of imaging. I opted for the Atik414 osc and it transofrmed my imaging and gave me lots of pleasure to use. OSCs seem to be derided by many but they have their place and I still use mine for the ocassional astro session when I use the ED80 to which it is permanently attached and 'ready to go'. I eventually progressed(?) / moved on to an Atik428ex mono and now a ZWO1600MM-Pro Cooled but I learnt so much from the osc. Have to say most of the time I now use the ASI1600 with either a Samyang 135mm or a WO-ZS71 but that is largely because my interest shifted from imaging galaxies to narrow band imaging of nebula. Good luck!

Well I cannot answer that one! I was a committed PI user and had tried with limited success to complete mosaics to an acceptable standard. Yes it can be done but to be honest I have better things to do in life than the excessively protracted procedure required to get good results. (I know others will argue differently). With APP you just load in the lights and calibration frames and it gets on with the job with minimal intervention. For mosaics it is a dream. I still use PI to process the image and PS to colour tweak but I now use APP pretty much exclusively for all pre-processing. Adrian

Astro-Pixel-Processor. I chose to 'rent' as opposed to buy - either way it is good value IMHO.

APP is magic when it comes to mosaics - well worth the money in my view. Thank you. Adrian

Thank you! I was lucky to have two clear moonless nights so I got much better and more consistent results with the OIII than normal. It would have been nice to have had astro darkness and longer nights but at least it was a rare opportunity to do something! I'll be interested to see the results from your Duo filter. Good luck. Adrian

Hi Alan, In an attempt to answer your question I have processed the rgb data I took from a night of imaging the Veil with my 1600 and Samyang 135mm; we actually had three clear nights here - unheard of! - and the first night I imaged the Veil in rgb, Ha and OIII but was not overly impressed with the end result - hence the change to the ZS71+1600 and two pane mosaic. This is only a quick process (pre-processed in APP, and then PI using ABE, AdaptiveStretch and combine in PixelMath); spending a lot more time may reveal more detail but hopefully it gives an idea. Adrian

Hi Alan, Thank you. It is taken with Ha (7nm) and OIII (8nm) filters. If I understand your question correctly I imaged it using RGB filters on the first night (for star colour as much as anything) but I found the nebula was barely visible using 60s exposures. Sky Safari says it has a magnitude of +5.00 but I have no experience of visual astronomy (other than low power binoculars) so not sure how easy it would be to discern. HTH Adrian

Two consecutive clear nights with no moon is almost inconceivable! Not that I'm complaining. Managed to get the Eastern Veil last night to add to the Western Veil from the night before. Both halves are 30x120s of Ha and 30x120s of OIII using an ASI1600-Pro Cooled at 139 gain / 56 offset. Mosaic created in APP - it took two hours to do each filter - that's half the imaging time! Processed in PI (DBE, LinearFit, AdaptiveStretch) and combined in PixelMath with 40%-Ha and 60%-OIII in the Green channel. All followed by a tiny colour tweak in PS and minimal noise reduction. Please feel free to offer CC - it's the only way to improve. Thanks for looking. Adrian

Thank you for the kind comments. Yes, I did use my 1.25" filters. I've set up my ZWO-EFW with RGB+Ha+OIII. I never seem to get along with L very well and in the past I've ended up not using it at all, so I figured taking L out and replacing it with OIII might be better. All my previous NB images have been with a manual 2" filter setup and I was wondering if the focus issue might be down to the smaller filters but I don't know - I'm clutching at straws really. Thank you Gina - I'm glad you like it. So far I am really liking the results I have achieved with the ASI1600. Maybe I need to be more adverturous with gain/offset settings but I like the fact that lots of shorter exposures give very good results. There is also less wastage compared with the 300s and 600s subs I have been taking with my CCD - living on the East Midlands flight path can be very frustrating! Adrian

Despite the lack of astro darkness last night turned out to be quite rewarding and provided a first opportunity to use my recently (February!) acquired ASI1600 with my WO-ZS71 and ZWO-EFW. This is 30x120s of Ha + 30x120s of OIII , gain 139, offset 56. Pre-processed in APP and then processed in PI with a final colour adjustment in PS. This is the first time I have imaged Ha and OIII and found the background levels to be almost identical; using LinearFit in PI made no discernible change at all to the OIII. Focus could have been better I feel. I just could not get below FWHM of 2.1 on either filter using SharpCap and SGPro gave an average HFR of 1.4 Thank you for looking. Adrian

Hi Doug, I purchased an ASI-1600 Pro in late February and so far have had little time to use it - weather and all. I was also confused by the various settings and found this article on CN site to be very helpful: https://www.cloudynights.com/topic/573886-sub-exposure-tables-for-asi-1600-and-maybe-qhy163/ I have used the tables as a starting point and so far have been very pleased with the results I have achieved, however, there is clearly much in the way of experimentation to be done. I live in a Bortle 5 area (and with all the new build I think going on Bortle 6!) - 19.93 Magnitude. Apologies if you have already seen this and I am telling you nothing new. Adrian

Good luck with the light panel - at least it should provide consistent and repeatable results.

Very nice Scott. It is a joy of a lens to use and I've been very satisfied with the results I have obtained using the ASI1600, my Atik428ex and my Canon 70D. It's great to see what others have achieved on a variety of targets. Adrian

Hi Scott. I put some details here: The filter wheel in the ZWO Mini EFW. More than happy to provide more detail if you'd like. Adrian

This is my first RGB image with the Samyang 135mm/ASI1600 combination albeit with some Ha and OIII added for good measure! I'm amazed I got anything at all with the short night and clouds. In total this is 210s Red, 90s Green, 120s Blue, 720s Ha and 600s OIII all pre-processed in APP, processed and combined in PI PixelMath followed by a little colour tweaking in PS. The RGB were all 30s exposures, the NB was all 120s exposures. Even at 30s there was clear signal on the RGB Spacing is really sensitive and as things stand I can only go as far as f4 and get reasonable FWHM values of less than 2.0. Adrian

Well I’m not sure. In SGP I go for 30,000 - 32,000 or thereabouts. That’s always worked for me. Have a go at a range of settings and see what works best. 😊

Sorry about that - it's getting late and I wasn't concentrating on what you wrote regarding the flats. You can take darks at any convenient time as long as they are at the same temperature, exposure, gain and offset. Complete darkness is essential. People often use the sensor cover supplied with the camera; some advocate wrapping it in tin-foil. The considered view is poor darks introduce more problems than they solve. I guess you can say the same for any calibration frame! I usually take my flats the following morning - I'm usually too tired to do it at the end of an imaging session. I can't see it being an issue providing you don't disturb the imaging train at all. If dust bunnies move they can often be reduced during processing. The flats will really help with the vignetting. You should take the dark-flats at the same time but with the lens cap on. It's all going in the right direction and looking good! Apologies again for not registering the lack of flats and darks. Adrian

Hi David, Well I've had a go. On the positive side this is a really well framed image of M101. I would say you have definitely improved the focus issues you were experiencing. Don't forget that achievable absolute FWHM is dependent on so many things and trying to achieve some magic low value on any given night is pointless. In my view you need to achieve the lowest value you can for a given filter - they will all vary. With my ED80DS I find that blue never focusses as well as red, green or luminance. Many of my rgb images suffer from blue bloat around the stars. On the negative side the flats are clearly not doing what they should be doing as all the masters exhibit severe vignetting and evidence of dust bunnies; I would suggest the latter are on the filters as they move from filter to filter. Having said that I have done my best (I'm sure others could do better) to reduce the effect of vignetting and dust bunnies as much as possible, probably at the expense of some of the outer arms of M101. I've processed pretty much as before but this time I also used the Luminance image as a 'Lighten' layer in Photoshop at about 45% opacity. Can you post one of the master flats - anyone - so I can have a look please. HTH Adrian

Will certainly take a look and get back to you later/tomorrow.

Good luck David! Hope you get some good results tonight; not easy on these short nights when Mr Moon is up and about but it's still a good opportunity to sort out a few niggling issues and problems. Next time I get my gear out I will be sure to screenshot the focussing results I get with SharpCap for comparison. Looking forward to seeing the results of tonights endeavours! Adrian

From purely personal experience I have found SGP hdr focussing not to yield good or consistent results. I have wasted so much time trying to get autofocus to work that I now focus manually, albeit with a stepper motor focus unit - I go and stand outside and use SharpCap on a laptop - five minutes (if that) and I'm done. As for SharpCap I've decided £10 year is money well spent; it is constantly being updated and improved. I use both the FWHM Measurement and Bahtinov Mask options and find I get very good results. Solving problems is all part of the fun! Not sure you ever reach the point where you've solved 'em all though! Good luck. Adrian

Hi David, I've used a BM with and without success. I've recently started using SharpCap (£10 per year) to help me focus with a preference for FWHM measurements but success depends on so many things, including the 'seeing'. I do pretty much the same but I have had more success using a uniform light source; I use my iPad running a lightbox type app and get very consistent results; the flats also work! Well done you! I'd be happy to have that average over an imaging session. tiff is just fine but I wonder whether it is DSS that decided to save as rgb rather than greyscale. I presume you have checked it is expecting to process mono images - it's in one of the Settings menus somewhere - can't exactly remember where though. As for the artefacts I'm really not sure what to say - it doesn't look like dew to me. It may be the flats just not doing their job properly. Another thing I would say is that the advice seems to be not to use Bias with a ASI1600 Pro. Rightly or wrongly (but it seems to work for me) I've started using flats + dark + dark-flats (instead of bias). If I'm doing something very wrong then hopefully someone will pop up and put me straight! Dark-flats are exposures taken with exactly the same exposure times as the corresponding flats but with the lens cap on - hence dark! You can use them in DSS. I would have another bash at taking your flats. I know dust bunnies may have moved but it might correct the vignetting problems you are experiencing. People use a variety of white light panels; I tried using one of the Huion panels but found it gave me severe 'banding' when used with both my dslr and ccd's so I gave up. HTH Adrian

Well I managed to get something for you although I'm sure those with more expertise could achieve far better. All the individual masters were rgb so I converted them to greyscale. I haven't used the Luminance master. I took them into PixInsight, cropped the vignetting (not sure the flats are doing the best job for you) and then applied AutomaticBackgroundExtraction (ABE) twice, once as subtraction and then as division. I then created a luminance mask and applied some noise reduction. I then duplicated the image and to one I applied incremental/multiple HistogramTransformation (HT) and the other I applied an ArcSinhStretch. I took the resulting images into Photoshop and layered the HT image over the ArcSinh image as a lighten layer with about 40% opacity. Finally I applied a little bit of extra noise reduction. You can definitely tell it is M81! Maybe the focus could be a bit tighter and there are a few artifacts on the masters I don't understand (especially the red for some reason) but hey! - you got a pretty good first image hiding in amongst all that data. HTH Adrian P.S. May I ask how you are taking your flats?

I think it is amazing what this 135mm @ f2 plus the ASI1600 @ unity gain, offset 50 can achieve on a 50% moon night; this is 25 x 120s of Ha and 20 x 120s of OIII taken between 23.50 and 01.30 last night. Sadr Processed in PI with a final colour tweak in PS. Adrian

Really frustrating with all the clouds of late which is stopping me experimenting with my new ASI1600 with the Samyang 135mm. There might be undersampling but I still love the level detail combined with the wide'ish field of view - a compromise I can live with. This is IC1396; 12x120s + 12x180s + 12x240s all at 200 gain/50 offset pre-processed separately in APP and then combined as HDR in PI, followed by a little bit of tweaking in PS. Stars removed using Annie's Astro Actions in PS. Next time I'll aim to get all of Sh2-129 in the shot as well! Thanks for looking. Adrian