Adreneline

I couldn't even get it in touching the glass! Every time I tried the threads crossed or it just fell out. I took it back to RVO and they couldn't do it either so I'm afraid I gave up in the end. Hope you have better luck. Adrian

Me too! In fact I'm a bit disappointed but there it is. I use an app on my iPad as a light source and found it was best to set an exposure time (e.g. 2 seconds or whatever) on the ASIair and then adjust the screen brightness to get the histogram peak mid-way along the axis. As you recommended I took dark-flats at the same time. Got there in the end but it's not as easy as it is with something like SGPro. Adrian

Interested to see you appear to be using a circular profile pully belt to transfer drive from the stepper to the focusser. This may be a total red herring (apologies in advance) but many (many) years ago as part of my degree I made a hifi (?) turntable using a dc motor and direct belt drive to the rim of the turntable (copied a commercial design available at the time) - made the whole thing from garish coloured perspex. I did all the calcs to size the pulley and turntable so the dc motor gave the desired 33 rpm. First test resulted in the rpm being substantially out - nothing to do with my calcs - all down to procession of the belt on the pulley and turntable rim. Had I used a toothed belt there would have been no problem. In the end it came down to trial and error to size the pulley correctly to the turntable diameter. Procession of the belt caused real problems which I would have thought would be exacerbated with backward and forward movements and repeatability of exact relative positions required with a focusser. Apologies again of this is a complete red herring. Adrian P.S. I have made stepper and d.c. motor focus units and always used toothed timing belts - mind you I have still had problems with autofocus in SGPro.

Shame you missed M13 but there's always another night. Good luck. Adrian

Excellent job to my eyes Adam - really like the star colours. An added bonus is there is so much to see in the image in terms of other 'fuzzies'. Thanks for sharing. Adrian

Hi Astroberry users. I am a new Astroberry user and I am seriously confused by one aspect in particular when using Astroberry, namely Home and Park. I think I understand that Home is what I have hitherto referred to as 'park' when I park the mount at the end of the evening and Park is where one might choose to position the mount (with OTA) so you can close the observatory roof (if you have one - which I don't!). Please correct me if I have that wrong. I've tried setting the Home position and I've tried setting Park to be the same as Home but no matter what I do when I select Park at the end of a session the mount (iOptron CEM25EC) goes off to some random position; on one occasion I am pretty convinced the OTA would have hit the mount had I not been there to switch if off - pull the plug! I also discovered tonight that Astroberry had somehow redefined the Home position I had set in the mount Hand Set so that when I used it to park the mount in my home position it once again went off to some random location. Can someone give me some clues as to what I am doing wrong. As things stand I dare not use the option to Park the mount at the end of an imaging session - so I will be getting up at 03.30 to park it manually. Most other aspects of Astroberry I am starting to get to grips with it's just this aspect that is giving me some grief. Thanks in advance. Adrian

It certainly does work a treat! Obtaining a half decent focus used to be the bane of my life when I first started out. I could get a pretty good result using my dslr with the FWHM feature in BackYardEoS but as soon as I started using a cooled CCD with SGPro it used to drive me mad and I wasted so much time trying to minimise the HFR reading for the image. I now use my iPad with a Bahtinov Mask and the pinch-zoom feature on the iPad works pretty much just like a magnifying glass. Onward and upward! Adrian P.S. Also meant to say you've got some nice star colours coming through as well.

Nice image - looks like you nailed the focus pretty well too. Hope you don't mind but I thought I'd plate solve your image in PixInsight.

Very nice Mark - PI can be a challenge but looks like you are geting it well sorted. Did you dither during capture? Adrian

Well I've used it with PHD2 and it seems to work just fine either with self picking the guide star or letting PHD2 auto pick. In the end I used SharpCap to help me focus the mini guider. All I found was that when you found the best focus position the process of 'locking off' could alter it again; it just took a bit of patience and persistence to get it sorted. No doubt about the fact that it works and it is definitely light weight and easy to mount.

I use the above combination with a light weight Samyang 135mm + ASI1600 combination. The mini guide system works very well but I did find it quite tricky to get an acceptable level of focus with the guide scope. The focus ring and locking arrangement is ok but I found it requires patience and persistence to focus well. Once focussed and locked off it works very well. Adrian

Nicely framed image David. Can I suggest not making the background quite as black - I think it may be a bit clipped. I was given some very good advice to set the background at around R:G:B - 23:23:23 or there abouts. If you do that on your image it may reveal more of the nebulosity around M81 & M82. Adrian

Out of interest how does your proposed approach differ/compare from/with Photometric Colour Calibration in PixInsight? Adrian

And now they have appeared on mine - very weird.

Hi @vlaiv. Don’t know if it’s just me but none of the images after the QE graph show anything - it’s just a uniform grey box. Adrian

This is IC1396 and Sh2-129 in Ha - 4 hours 24 mins of 180s exposures, unguided - all on the same night! Calibated and integrated in APP followed by ABE, HT, LHE and masked HDRM in PI and finally minimal noise reduction in PS ... .. and annotated in PI APP reported FWHM of less than 1.5 on every frame so quite pleased I've got focus and spacing pretty well sorted. Just need the same amount of OIII.

I really like the colours - very nice image. I’ve been meaning to revisit old data with new skills and now I’ve got time on my hands I really ought to do it! Adrian

I know this is probably cheating but this is a composite of six separate 16 bit mono images taken with my Allsky camera (ASI120MM-S) on the 21st. Out of over 1000 images just six clearly showed signs of meteor activity. I aligned each frame using DynamicAlignment in PixInsight , layered them in Photoshop with a Hide All mask and then allowed the meteor to be revealed as a Lighten layer. Relatively they are all in the correct place with regard to the Plough but the times were spread throughout the night. Have to say I expected to see a few more. I did the same on 20th-21st and only recorded one meteor in 750 images. The 22nd-23rd was worse - nothing! Bottom of the picture is pretty much due East. Apologies for the quality of the image. Thanks for looking. Adrian

Hi Roger, You certainly want to achieve focus with the focus mark aligned somewhere in the base of the 'L'. The only way I have found to do this is to experiment with various spacer combinations to get the correct spacing. Nominally it should be 44mm but my experience is it is always more. You will find that even introducing a 0.2mm shim spacer will make a lot of difference to the focus position - it is very sensitive to getting the spacing correct, especially at f2. I spent last night trying to marry up my Samyang 85mm to my Atik414ex-osc. After a couple of hours I decided to stop and have a go another night. I'm pretty close but I think I need another 0.15mm shim spacer which I don't have. Frustration! If I stop the lens down to more like f8 I can achieve focus but opening it up to f1.2 and I can't get focus within the limits of the 'L' mark. It's all down to trial and error I'm afraid - and perseverance! Good luck! Adrian P.S. I use SharpCap FWHM whilst I'm getting things sorted - I'll use a BM once I've basically got it all sorted with the correct spacers/shims.

Had me worried there. Hopefully you don't have your wellies on!

Interesting. Not sure why there appears to be banding in the second image. The last one looks pretty comparable to my flats. Which filters are you using? Adrian

A very kind offer Ole and one I will take you up on once I've got my ED80 system up and running again. My ED80 has a ZWO-EFW and HitecAstro focus system but at present no camera attached. I'm sure my failure to get SGPro to work is purely down to operator error so any guidance would be appreciated. I'll get back to you Adrian

I've had exactly this effect on both my 414ex-osc and (before I sold it) my 428ex-mono. I only used to see it when making flats and I would have to wait 5 or 10 minutes for these triangular areas to subside to the left and right and fade to nothing. I have no idea what it is and it may indeed be moisture but it never seemed to have any effect on the images. Sorry I can't be of more help but I'm pretty sure it is nothing much to worry about. Adrian

No, I didn't guide so didn't dither. I find the CEM25 very good at tracking certainly up to 180s and so far my attempts at guiding with the ASIair and ZWO120mini +guide scope have not been encouraging - possibly/probably due to my bad setup of the PHD clone within the ASIair. I'll take a closer look at the image because I hadn't noticed the artefacts. Thank you. Adrian

Yes, but the greatest improvement was in the peripheral stars in the extreme corners of the image - there was no real discernible difference for stars in the central region. As you are finding even tiny changes in spacing make a huge difference to the focus position. It is worth the effort in the end. Good luck. Adrian