69boss302

That is correct, 2600MC Pro OSC, no filters (yet). I do have a zwo duoband though.   Vlaiv, it seems what I need to do is pay closer attention to my atmospheric conditions next time, before I do any dramatic changes. Or any changes at all in fact.  I remember the other night I tossed a bunch of lights because of whispy clouds in the shots, so that does tell me it wasnt great.  I tend to dismiss it as just that though and didnt really consider that the evening was not great for shooting. I will pay much closer attention next time.  Its been really rough here for the last month and a half, so even a semi reasonable night, Im going out there! Its been 2-3 nights in the last 2 months

Wow so much good information, thank you again!   OK good news on the camera / OTA match, I did do some homework before buying it all and thats what I came up with so Im glad to hear that.  I am actually in a pretty good spot for viewing, top of a hill, no water and Bortel 3/4. Not near any big cities. It gets pretty dark out here.  I will read up on getting better tracking, I know thats vital, thank you for that.  As for visual conditions, when I start out its not so bad, but admittedly I do go in and get some sleep.  Maybe the conditions change throughout the night.  I do know that a few nights ago wasnt ideal, it had a thin layer.  Ill pay more attention to that next time.  Now... on to the field flattener.... Thats a good possibility. I remember thinking how sharp my center stars were before I got the FF (stacked tiff image attached).  I decided to stay with the one 'made' for my Z73 and my assumptions were that it would be best for it but maybe Im wrong on that. Have you any recommendations for a better quality one?  THank you for helping me nail this down!

Bob

Andromeda2.tif

1 hour ago, ONIKKINEN said:

There could be frost developing on surfaces other than the objective lens, even inside the tube if you have moisture in there for some reason. I find a thin layer of frost develops quickly and is difficult to see by eye but the camera will pick this up as a dimming/bloating effect.

How do you handle the gear after shooting? Do you open all the caps for several hours to let moisture out before putting the gear back to storage? If you dont, you could have moisture lingering inside the tube which sets as frost to a corrector/filter/inside of the lens or whatever and wkuld be difficult to spot with the objective lens being dry to the outside.

Generally when I bring it back inside, I put it on the sofa and go to bed and worry about it next morning, so it does have a few hours of getting back to room temp.

@vlaiv If I am understanding you correctly, I likely have the wrong camera for my scope?

@vlaiv Thank you! Wow some really good info there. I think I should start with my basics of good guiding.  I do the pa then it does its guiding with almost no input from me, so I just let it go and never pay much attention to it other than look at the graph on occasion.   I do have a dew heater and use it! Its cold up here in CT this time of year.  Ill also check my objective lens for cleanliness but Im fairly fanatical about lens cap etc.  I dont have the guiding specs for this rosette picture, however I did just happen to capture a screen shot from when I shot horsehead, and I think my horsehead came out very nice (for a beginner)...!

@vlaiv Thank you, that is a great suggestion, I have attached my stacked fits to this, maybe someone can make something out of it!   As for focus, I have the ZWO EAF and do a focus routine before PA each time, as well as a temp change and Meridian flip, so hopefully that is enough.  I also have no filter but it seems I should.... 

Rosette.TIF

@Budgie1thank you for this. Just shows I have so much to learn still. Thats not a bad thing.... Ill get there. You guys are the best, thank you.

@mike1485 Thank you, and  I think you nailed it, I do use Histogram Transfomation!  And you are also correct in that I comment on your new script and I look forward to giving it a try. My plan is to read about it tonight when I get out of work. Looking forward to it!

@vlaivthank you for that great response, much appreciated. I am indeed using a Z73, however I am using no filters, maybe I should try the one you suggest.  I think I have guiding pretty tight, but can see if I can improve it a tad. Im thinking it is the way I process... the individual .fit files dont have bloated stars, so it must be something Im doing in the process...

@scotty38 On a side note, when I remove stars using Starnet++, its a really blotchy image. I was hoping to reduce the stars in the original image and not as much in post...

I have removed stars with Starnet, but never added them back again with pixelmath! Ill definitely try that, thank you!

Seems odd saying I have too many stars in my pictures on an astrophotography board!  But when I do some Nebulas...actually almost anything... I get predominant stars where I want the nebula to be the main attraction. Example below...  I do all my calibration frames, stack in DSS, and process in PI. Pretty basic processing.  The image below, Soul Nebula,  was about 57 lights at 300 sec each.  Is the secret more lights but shorter duration?  I really dont love the outcome of a lot of the stuff I do.  As always, any tips much appreciated.

Bob

This sounds interesting. Thank you for putting in all that work and sharing it with the community, I will try it as soon as I can! Just out of curiosity, do you have any comparison pictures?

Ill start out by saying Im VERY new to this and am by no means any good at it      Last night I spent some time on horsehead/flame nebulae and stacked it in DSS and  processed it through pixinsight.  I have watched dozens of youtube videos on it and they have helped a lot, however my end result isnt as good as it should be I dont think. This is an example of what I got last night after all was said and done. I think about 4.5 hours of lights, stacked with darks/flats/bias etc.   If I look  at reference pictures of this, its not as 'rust red' colored, the thin nebulosity is more dramatic on others, and they just seem more overall pleasing to the eyes. 

Gear listed in my sig.. this was 57 (I think) 300 sec lights.  I saved the tiff out of DSS as 32 bit and used that, not its autosave. I included it here in case anyone wants to play.

Thank you for any pointers!

Bob

Horsehead 32bit.TIF

I know Im new to this so I apologize in advance, but what is ABS?

You can get a longer dovetail or you add a front threaded (1/4-20) weight. I got a couple of small ones off amazon but also machined my own for a little bigger one, and it worked great!

Just as a followup Ive been having amazing luck with the 2600 MC Pro OSC.  Last night I went out for a while and took some shots, but when my target went below the horizon I switched to a new one,  The Horsehead Nebula. Well, as it turns out, I got exactly ONE shot out of it before my battery box died so most of the night was wasted. Just for kicks, I processed that single frame in PI in a real hasty and crappy manner just to see what it would come out like.  As luck would have it, a meteor went through it. For a single 180 second shot, Im just amazed how well it came out!   Again its just a really quick processing to see what one frame can do...

@wimvb Thank you for your very helpful reply. Yes, generally I do use flats, but did not this time. I do have flats that I shot during the session and will reprocess and see if it helps. Thank you.  Im glad its a normal occurrence and nothing to worry about.  As for the dot, I will clean my optical train and see what happens! Once again, thank you for your reply.

Bob

That dot does not appear to be in any of my original .fit files, nor in the autosave.tif file from DSS. Only in PI

Here is that dot in the finished product

Also, on the main picture I always have this 'clear' dot in the same spot all the time. This is the artificially stretched shot, but you do still see it in the final product:

Whenever I do background subtraction in PixInsight, I get a very uneven field, but it seems to be consistent among my photo sessions. (see extracted background below).  PI seems to take care of it just fine but it seems to me it shouldnt be like this.  I have a Z73 with 73a field flattener and ZWO EAF. Camera is ZWO 2600 MC Pro OSC, cooler on, and AA+ taking the pictures.  I use dynamic background extraction, not automatic. Seems to work better but still get same basic results. Is this normal or should I be concerned?

Thank you guys, yes, still a little bit left to go, but at least I know Im on the right track now! Im sure itll take me several nights to get it dialed in.

Just to follow up with you, I added that extra extension and last night I did some shots. Although the skies werent great, it was enough to see that it fixed the issue!  A VERY quick and dirty NGC7000 shows the corners as being much better. Thank you all for your amazing advice.

Bob

thank you @Phillyo. I added the extra extension last night, and today I will test and report back I hope this does it!