richyrich_one Posted January 5, 2017 Author Share Posted January 5, 2017 On 03/01/2017 at 09:34, Chris Lock said: I doubt there would be, I've seen pinched optics with both lenses and mirrors, and once loosened they are generally fine On 03/01/2017 at 09:44, Peter Drew said: I agree. Mirror nice and loose and yet no difference. Really starting to think it's mullered. Link to comment Share on other sites More sharing options...
Davey-T Posted January 5, 2017 Share Posted January 5, 2017 So was it alright before flocking, have you got a pre flock picture ? Dave Link to comment Share on other sites More sharing options...
richyrich_one Posted January 5, 2017 Author Share Posted January 5, 2017 5 minutes ago, Davey-T said: So was it alright before flocking, have you got a pre flock picture ? Dave I can't be 100% sure when I did it but fairly sure this was before. I have had decent shots after flocking but not since I slackened the mirror off after suspected sensor tilt on the camera. And this is a sub using the same camera but on the 250P-DS a couple of nights ago. I can't get anything approaching this with the 130 Link to comment Share on other sites More sharing options...
Thalestris24 Posted January 5, 2017 Share Posted January 5, 2017 Hi Rich I've had similar problems with my 130pds which is one reason I haven't used it since early last year (in comparison, a frac (or a lens) is a dream to use! I think I boiled it down to tilt in the focusser. It can be centered (see Astronomyshed video on tweaking the quattro) but I've not got around to attempting it - yet. Louise Link to comment Share on other sites More sharing options...
richyrich_one Posted January 5, 2017 Author Share Posted January 5, 2017 2 minutes ago, Thalestris24 said: Hi Rich I've had similar problems with my 130pds which is one reason I haven't used it since early last year (in comparison, a frac (or a lens) is a dream to use! I think I boiled it down to tilt in the focusser. It can be centered (see Astronomyshed video on tweaking the quattro) but I've not got around to attempting it - yet. Louise I hear you, and glad of any suggestions. I actually recently went through checking the focuser and all seemed ok to me. Link to comment Share on other sites More sharing options...
Thalestris24 Posted January 5, 2017 Share Posted January 5, 2017 The focusser itself does have collimation screws but there is a design flaw if you need to adjust them! It's not easy to determine whether it is slightly tilted but Dion does a good tutorial using the quattro: from about 43:10 He makes it all look so easy! I think with the 130pds you can easily get tilt because the tube metal is a bit on the thin side. Anyway, it was just a thought as you've been running out of ideas... Link to comment Share on other sites More sharing options...
richyrich_one Posted January 5, 2017 Author Share Posted January 5, 2017 No worries Louise, I'll check it again. Link to comment Share on other sites More sharing options...
Chris Posted January 5, 2017 Share Posted January 5, 2017 I don't think pinching is the problem in that case. Make sure you haven't gone to loose with the primary mirror clips else you might get mirror flop. I honestly don't think your image is that bad on the face of it, bear in mind that I can't zoom right in close. when I had pinching my stars were literally figure of 8 shaped, no joke. I'm starting to think that you would be much happier with an ED/Apo refractor - perfectly round stars and you only usually need to adjust your flattener spacing to get the corners right. Link to comment Share on other sites More sharing options...
richyrich_one Posted January 5, 2017 Author Share Posted January 5, 2017 53 minutes ago, Chris Lock said: I don't think pinching is the problem in that case. Make sure you haven't gone to loose with the primary mirror clips else you might get mirror flop. I honestly don't think your image is that bad on the face of it, bear in mind that I can't zoom right in close. when I had pinching my stars were literally figure of 8 shaped, no joke. I'm starting to think that you would be much happier with an ED/Apo refractor - perfectly round stars and you only usually need to adjust your flattener spacing to get the corners right. There definitely was some flop, I had to recollimate after slewing. A frac is starting to look tempting I have to say. But it will forever bug me if I don't get to the bottom of this. It shouldn't be this difficult. There is something fundamentally wrong somewhere so I am going to give it one more try from the ground up. I noticed that when collimating the primary last night that either I can get the reflection of the crosshairs centered or the central hole in the Cheshire but not both at the same time. To my mind that's pointing to some kind of focuser misalignment so going to start there. I also noticed some slight play which seems to be from between the base plate and the rest of the focuser. I've had some good stuff from this scope and I want it back! Link to comment Share on other sites More sharing options...
Peter Drew Posted January 5, 2017 Share Posted January 5, 2017 An easy way to test whether the primary mirror is at fault is to rotate it through 90 degrees and see if the issue revolves with it. Link to comment Share on other sites More sharing options...
Skyline Posted January 5, 2017 Share Posted January 5, 2017 Always start from the primary end of the scope. Make sure the mirror cell is ok, primary, springs and locking screws are good. Loosen the mirror clips, take out mirror or move the primary freely around the cell, mount clips back on, I have always made sure my clips are just slightly touching the edge surface of the mirror loosely without any forced applied. The whole point of those clips is just to stop the mirror falling out of the cell. Remove spider vane with secondary holder Check focuser, adjust as needed, fit focuser back - Focuser base 1st, make sure it is mounted square on tube and bolts and nuts are tight. If your using a skywatcher focuser Get a Vernier Caliper and measure the depth of the focuser lip on all three contact points on skywatcher focuser base to make sure tilt on base are equal around base. Fit back spider vanes with secondary and make sure secondary is on axis, recollimate secondary 1st with a sightube and collimate primary with chesire. Do visual star test Link to comment Share on other sites More sharing options...
iapa Posted January 5, 2017 Share Posted January 5, 2017 1 hour ago, Skyline said: Always start from the primary end of the scope. Make sure the mirror cell is ok, primary and locking screws are good. Loosen the mirror clips, take out mirror or move the primary freely around the cell, mount clips back on, I have always made sure my the clips are just slightly touching the edge surface of the mirror loosely without any forced applied. The whole point of those clips is just to stop the mirror falling out of the cell. Remove spider vane with secondary holder Check focuser, adjust as needed, fit focuser back, make sure it is mounted square on tube and bolts and nuts are tight. If your using a skywatcher focuser Get a Vernier Caliper and measure the depth on all three contact points on skywatcher focuser base to make sure tilt on base are equal on around base. Fit back spider vanes with secondary and make sure secondary is on axis, recollimate secondary 1st with a sightube and collimate primary with chesire. Do visual star test No, can you do a video of all these steps - in detail - and post on youtube. Would be an excellent reference. Link to comment Share on other sites More sharing options...
wornish Posted January 5, 2017 Share Posted January 5, 2017 No offence to anyone but I can't believe this thread is for real. Who views an image magnified so much that you can almost see the pixels ? Its meant to be a hobby not a science experiment, at least thats how I treat it. At the end of the day you can use Pixinsight or PS and morphologically change the stars to look like what you want and no one would even know. I would be more than happy with the image originally posted. Just saying. Link to comment Share on other sites More sharing options...
richyrich_one Posted January 5, 2017 Author Share Posted January 5, 2017 22 minutes ago, wornish said: Who views an image magnified so much that you can almost see the pixels ? That's an over exaggeration. Nothing wrong trying to correct a problem that wasn't present before. There is obvious distortion present that wasn't present before. Any serious imager would agree. I guess there will be those that settle for OK. I am not one of them. Link to comment Share on other sites More sharing options...
Davey-T Posted January 5, 2017 Share Posted January 5, 2017 36 minutes ago, wornish said: No offence to anyone but I can't believe this thread is for real. Who views an image magnified so much that you can almost see the pixels ? Its meant to be a hobby not a science experiment, at least thats how I treat it. At the end of the day you can use Pixinsight or PS and morphologically change the stars to look like what you want and no one would even know. I would be more than happy with the image originally posted. Just saying. The image posted on the forum is snapshot of the actual full size image which you can view by clicking on it and choosing "full size" then + you will then see what the problem is, this is not " pixel peeping " Dave Link to comment Share on other sites More sharing options...
Skyline Posted January 5, 2017 Share Posted January 5, 2017 2 hours ago, iapa said: No, can you do a video of all these steps - in detail - and post on youtube. Would be an excellent reference. Only if we had a 8th day in the week, otherwise time is too precious. Link to comment Share on other sites More sharing options...
wornish Posted January 5, 2017 Share Posted January 5, 2017 1 minute ago, Davey-T said: The image posted on the forum is snapshot of the actual full size image which you can view by clicking on it and choosing "full size" then + you will then see what the problem is, this is not " pixel peeping " Dave I did say I dont want to offend anyone in my post. I have already looked at the 100% version and to be honest, as others have said, you really have to look hard to see the slight variation. I am not been critical , there is nothing wrong in correcting distortion that has just appeared. That said I think people can lose perspective about what is a good or bad image. To want to "seriously pack it in" as the OP stated because of a very slightly distorted star in one corner does seem a little excessive IMHO. I am a relative newbie to astrophotography and can't match a lot of the posts on here, but that doesn't stop me trying or make me less serious about imaging. Link to comment Share on other sites More sharing options...
Chris Posted January 5, 2017 Share Posted January 5, 2017 25 minutes ago, wornish said: No offence to anyone but I can't believe this thread is for real. Who views an image magnified so much that you can almost see the pixels ? Its meant to be a hobby not a science experiment, at least thats how I treat it. At the end of the day you can use Pixinsight or PS and morphologically change the stars to look like what you want and no one would even know. I would be more than happy with the image originally posted. Just saying. I didn't think it looked too bad until I saw the the full size image. It really does show how bad the bottom left corner is if you click on the image and select full size. I'm not that fussy but I have to say it would bug me, it's not right. EDIT: cross post, I see you already saw the full size image and don't see a problem?? Link to comment Share on other sites More sharing options...
Davey-T Posted January 5, 2017 Share Posted January 5, 2017 13 minutes ago, wornish said: I did say I dont want to offend anyone in my post. I have already looked at the 100% version and to be honest, as others have said, you really have to look hard to see the slight variation. I am not been critical , there is nothing wrong in correcting distortion that has just appeared. That said I think people can lose perspective about what is a good or bad image. To want to "seriously pack it in" as the OP stated because of a very slightly distorted star in one corner does seem a little excessive IMHO. I am a relative newbie to astrophotography and can't match a lot of the posts on here, but that doesn't stop me trying or make me less serious about imaging. No one gets offended here, you must be thinking of CN Imaging folk who have spent loadsa money tend to have higher expectations that rise exponentially with the expense. Read some posts and you find folk obsessed with perfection and others like me who have long ago given up striving for perfection which is why you very rarely see my images posted. It's annoying having to try and correct unnecessary faults if you can fix it at source. Luckily we're all different it's what makes the world go round Dave Link to comment Share on other sites More sharing options...
Thalestris24 Posted January 5, 2017 Share Posted January 5, 2017 1 hour ago, wornish said: I did say I dont want to offend anyone in my post. I have already looked at the 100% version and to be honest, as others have said, you really have to look hard to see the slight variation. I am not been critical , there is nothing wrong in correcting distortion that has just appeared. That said I think people can lose perspective about what is a good or bad image. To want to "seriously pack it in" as the OP stated because of a very slightly distorted star in one corner does seem a little excessive IMHO. I am a relative newbie to astrophotography and can't match a lot of the posts on here, but that doesn't stop me trying or make me less serious about imaging. Hi You have to select 'full size' the click on the image again to zoom in to 100% view. You can clearly the see that the stars, especially on the left, have various distortions and elongations. No one would be happy with that! Generally speaking, problems mostly on one side of an image indicate tilt somewhere in the system's light path. Louise Link to comment Share on other sites More sharing options...
wornish Posted January 5, 2017 Share Posted January 5, 2017 16 minutes ago, Thalestris24 said: Hi You have to select 'full size' the click on the image again to zoom in to 100% view. You can clearly the see that the stars, especially on the left, have various distortions and elongations. No one would be happy with that! Generally speaking, problems mostly on one side of an image indicate tilt somewhere in the system's light path. Louise OK, I didn't do the second click to see the actual full size image, I can now see the double spikes and some distortions. BUT ... it would not make me want to "Pack It All In" which is what drew me to this thread in the first place; and yes I would also want to try to fix it. That said at normal viewing levels I would still be happy to share it with other "non serious" imagers, you should see some of my attempts if you want to have a laugh This kind of very critical assessment especially in the Starting Imaging Forum makes me not want to post anything for fear of been unworthy. I will shut up now. Link to comment Share on other sites More sharing options...
Chris Posted January 5, 2017 Share Posted January 5, 2017 Just now, wornish said: This kind of very critical assessment especially in the Starting Imaging Forum makes me not want to post anything for fear of been unworthy. I will shut up now. I have to say I think the 'standard' of images has gone up just in the 5 or so years I've been hanging around here. I don't post images often now days, but that's more to do with having 3 young kids than the increasing standards I see. Some of us need to fly the flag for rubbish pics else no one starting out will dare post lol Link to comment Share on other sites More sharing options...
iapa Posted January 5, 2017 Share Posted January 5, 2017 2 hours ago, wornish said: That said I think people can lose perspective about what is a good or bad image. To want to "seriously pack it in" as the OP stated To be fair - that is just the topic, OP did not originally at the end that "I don't want pack it in but I have completely lost the plot" I can relate to the sentiment - in this you often feel 'nuff!', SHMBO will concur on my behalf to this LOL - and I am way behind the OP in standard of work. To paraphrase an earlier respondent; the expectation increases with investment in time and money. Having said that - I would be equally determined to find the cause, and more importantly solution - to the issue here. Link to comment Share on other sites More sharing options...
Charic Posted January 5, 2017 Share Posted January 5, 2017 2 hours ago, Davey-T said: The image posted on the forum is snapshot of the actual full size image which you can view by clicking on it and choosing "full size" then + richyrich_one, I've Just had another look using Davey-T's advice............ I'm now really shocked you even posted such a dire image! Lol. Seriously, I missed that level of detail at first, hence my original " is this a test comment? " I've even been checking my own eyes? but I now understand your determination to improve on something that was, as you say, ok before. Keep at it, you`ll get there. Link to comment Share on other sites More sharing options...
iapa Posted January 5, 2017 Share Posted January 5, 2017 3 minutes ago, Chris Lock said: Some of us need to fly the flag for rubbish pics else no one starting out will dare post lol I'm more that nhappy to run something up the flag pole as an example of something below most people's expectations Link to comment Share on other sites More sharing options...
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