Jm1973

I'll try to get the ASCOM driver to work with my camera tonight. That's the best method really, as I can use the ASCOM option in Astro Tortilla as well, instead of the 'File Open Dialogue' method.

Great idea!

I hadn't seen that github. It looks like they have very recently made some updates to the Nikon side of things. Thanks!

Hi. Firstly thanks for the reply. You are quite correct, I am talking about manually taking a photo with my DSLR attached to the telescope (using digicamcontrol), and using the 'virtual camera' functionality in SharpCap to process the images within the Polar Alignment tool (assuming the virtual camera is integrated into the polar alignment module). However, PhotoPolarAlign sounds like it may be a viable alternative. I will take a look at that and see how well it works. Thanks for the tip! If anyone else uses SharpCap, I would still be interested in hearing whether the polar alignment module makes use of the virtual camera module.

I'm thinking of buying sharpcap, mainly for the polar alignment tool. However I have a nikon d3300 which is unsupported by sharpcap. Does sharpcap's 'virtual camera' feature work with its polar alignment tool? If so then I could take images and use them for polar alignment. I suppose the other possibility is to use as ascom, but last I checked there was no ascom driver for the d3300, although there had been talk of one. Does anyone know the answers to these questions? Many thanks.

I'm using a d3300. I was able to get a reasonable image of Andromeda with 30 second subs, so I thought 1 minute would be ok for something like wixard nebula. You may well be right though. I've managed to get rid of the vignetting, but by the time I have brought out any nebulosity, the stars are so bloated that the image is ruined. Obviously It doesn't help that they aren't in good focus to start with, but I even if the stars were in focus.. I wonder would I be able to do anything with this. This is the best I have been able to get. I would like to know whether it is my data that is bad, or my processing.. or both!

Do you stretch a tshirt or anything over the telescope, or do you just put the tablet straight over the end? Yeah they are out of focus. I'd been playing around with the settings on Astro tortilla and not having much luck, then I suddenly got it working so started shooting. It was only halfway through that I realised I hadn't got round to focussing properly. I haven't got a bahtinov mask yet, but my mum has bought me one for Christmas (I'm 47). I usually focus by finding a bright star and then zooming in fully using live view. When in focus the star will generally have diffraction spikes. Kind of like a poor man's bahtinov man I guess.

Well I just calibrated again but without the flats this time and the results look far more normal. So I think I need to look at my process for taking flats.

I don't know about better... I would say different. Instead of a reddish ring I now have this: I am still unable to get rid of the gradient, or even understand what's going on. I don't really understand how removing some slightly cloudy images has caused this to happen. Is it possible my flats are causing problems?

I just went through my 60 lights and removed 15 that had slight amounts of cloud in them (over and above the others). Stacking now. WIll report back later.

Hi Everyone. I am quite new to image processing, but with the help of this forum I have managed to get a reasonable image of ANdromeda recently. So bouyed with this small success I decided to take a shot (no pun intended) at Wizard Nebula. Using AstorTortilla I managed to get it pretty much centred in my sights, and took 60 subs at 60 seconds each before the clouds arrived. I also took 25 darks, 25 bias and 30 flats. I registered and stacked them in APP. But when I stretched them there was a very prominent red ring present, that I have struggled to remove as it is a very similar colour to the nebulosity I am trying to bring out. In fact in order to get the nebulosity to show at all, I have to stretch the image so much that the gradients are overpowering as are the stars. I have not had much luck clearing it up with either 'correct vignetting' or 'remove light pollution' in APP, and I've also not had much luck with removing the stars before stretching. Does anyone who is good at this sort of stuff fancy taking a look at my stacked fits image and see if anything can be done with it, or whether I should try stacking it differently? I don't want to spendanother evening messing about in PS, GIMP, APP etc. if it's a lost cause. I know there is data there as I can see the nebulosity when thoroughly stretched, but I can't seem to get to it without ruining the image. This is after stacking, then stretching, in APP. I'm not sure what caused the purple banding. . Here is a link to the FITS file: https://www.dropbox.com/s/4g46xszfuf4zlw2/Wizard_Nebula-RGB-session_1.fits?dl=0 Thanks in advance.

Ah.. that makes sense. I am definitely running some stuff as admin. I will check to make sure everything else is too. Thanks! edit: a quick update for anyone else with this issue: it worked! I launched Stellarium and AT with admin rights and both prgrams connected to my telescope. Another thing I've realised is the epoch didn't match across mount and both pieces of software. I have fixed this now too.

Hi everyone! I have a D3300, which doesn't play nicely with a lot of software, so I use digicamcontrol and have just started trying to use Astro Tortilla. With AT I have to use the 'file open dialogue' option, and manually take pics to use in order to refine my slew till it's spot on. This works well for the most part. However, most of the things I have read say to use somehting like Stellarium to slew to your target, then use AT to get a more accurate position. My problem is if I launch AT first, it connects to EQMOD and picks up my telescope (so far so good) but then when I launch Stellarium it says no COM port found (or something like that). And similarly if I launch Stellarium first, that connects to my telescope OK, but then AT fails to connect. What am I doing wrong? I can only seem to connect to one or the oher, but not both. This has worked so far as I have been using pics from old sessions to feed into AT to get my position, but if I want to go somewhere I haven't got pics of I don't really know how I'd do that, apart from getting photos from elsewhere and feeding that into AT. I had assumed assumed that both pieces of software would talk to each other, so that when I slewed to a position in Stellatrium, AT would know where I was aiming for, and thus when I then uploaded a photo of my actual position into AT it would be able to work out the difference and put me in the right place (possibly after multiple iterations). Does anyone have any experience with these software packages who could possibly enlighten me? Thanks for any help. Clear skies!

I've figured it out.

Hi All! I have just instaled ASCOM and EQMOD, and I can now control my telescope in EQMOD. I've just installed the latest version of Stellarium as iut now has native support for ASCOM, so no more StellariumScope required. I'm trying to add my telescope, but under Telescope>Add there is no option for ASCOM. I figure I must be doing something wrong, as apparently there should be an option for ASCOM telescope. Does anyone here use Stellarium and know how to add an ASCOM telescope please?

Hi. Thanks for the reply. At the time of taking the subs used in that image my kit consisted of a skywatcher 200p on an eq5 synscan pro goto, with an unmodified d3300 attached directly to the focusser with a T ring. A number of the subs have some trailing, one in particular is quite bad. However I think they are not primarily due to tracking issues, as many of them do not have trails at all. I think they are due to me not having an intervalometer, or shutter release, at the time so I had to manually push the button on the camera for each exposure. I think that caused a slight trail on a lot of the images. I may be wrong though. I took about 100 30-second subs, at iso800. Since then I've bought a long usb repeater cable, and nikon data cable and downloaded digicamcontrol, so if that was the cause of the trailing it shouldn't happen next time. Sadly the weather has been terrible the last few weeks, and even though tonight turned out to be unexpectedly clear, I'd agreed to watch a film with my better half, and didn't even realise the clouds had vacated until it was bedtime. Hopefully the clear weather will continue tomorrow evening. Clear skies.

Sorry for the bump, but did anything ever happen with this? I've just bought an eqdirect cable and installed ASCOM and EQMOD and want to start using Stellarium to control my telescope. Do I have to download old versions of Stellarium and stellarium-scope to get this to work, or are there other methods available?

As I've had no good weather lately to get the telescope out, I've gone back to some subs I took a while back. I had previously processed them entirely with GIMP. I was pleased with it as it was my first time stretching an image, but there was a lot of 'haloing' around the image and the core was very bright. I downloaded the free trial of APP and had another go at it. I used the 'Correct Vignetting' tool (which didn't seem to do an awful lot), and the 'Remove Light Pollution' tool which seemed to work quite well. Then I stretched with GIMP again. I think the result is a lot better. I am just waiting for clear skies now to get some other footage I can play with.

I might look at Xterminator, as I want to reach the limtis with Gimp and PS before exploring other software.. lest I get (even more) overwhelmed. I will try your idea for fixing the core tonight. Thanks again!

No problem. It's all very interesting, though a bit above my pay grade so to speak.

So I have got a little further with it now. I am bringing out more detail and more colour, but unfortunately I am also blowing out the core and background.

Thanks for the reply. A lot of what you are saying with gradients kind of goes over my head a bit, but you are not the first person to tell me I should be using more flats. I only used 10 in this image. The next time I get a clear night I will take more. You have managed to get my data looking pretty amazing, as far as I am concerned. I would be very happy if I could get to that stage. I'll have a look at arcsinh stretch. Assuming it is on my rather old version of PS.

Hi. Thanks for the comments. LP filters seem to vary in price from a few quid up to over a hundred. How much would I need to spend to get something that would help. Are there any particular brands worth buying? I'm trying not to break the bank.

@ollypenrice II've just spent an hour or so following along with your steps. I feel I have learnt a fair bit about where tools are in PS I start with moving the black point up the same amount as you did: Giving this: I can't move the black point again as much as you did now, but I move it up to 7, being careful not to clip the histogram: Giving this: Next I zoom in to make sure there are no stars etc where I sample, and I sample 4 points in the black. But the RGB values I get are very low. Nowhere near 22-23. Not sure what I did there. I played about with changing values with colour balance, but I could only tweak them in relation to each other, not increase them overall. I cannot slide the black point any further to the right without clipping the histogram, so I've had to leave the RGB values where they are. Ah well, onward and upward! So I continued on to the curves. I have tried to emulate the curve you did, and I got something like this: I noticed that my histogram is further to the left than yours at this point, not sure why that is. Setting the points on the curves is quite the fiddly task! Finally I got something resembling your curve and ended up with this! This is a lot better than I had previously, and I feel I have learnt some useful stuff. Lots of practise is what's needed now! I am confused about how the RGB values were so off though....

Hi. You were correct. There was one particular RAW file which had very pronounced trailing, much more so than any other. I have taken that one out, and also a number of other ones with a smaller amount of trailing. I am re-stacking now, and will see how it turns out. Thank you for your insight, and you're great work with the image.