Astrocookie Posted April 8, 2013 Share Posted April 8, 2013 http://s1341.photobucket.com/user/Astrocookie/media/C2011_L4_2013_04_02_Final02_zps75937c5d.jpg.html?sort=3&o=4 Here's my final images of Panstarrs. Critique welcome Sorry its in DSO's (didn't know where else to put it!) Paul Link to comment Share on other sites More sharing options...
Astrocookie Posted April 10, 2013 Author Share Posted April 10, 2013 What no critique !!!! Are they that bad ;-) Link to comment Share on other sites More sharing options...
Guest Steve Posted April 10, 2013 Share Posted April 10, 2013 Look's good to me! Link to comment Share on other sites More sharing options...
angusw2 Posted April 10, 2013 Share Posted April 10, 2013 Better than my image Paul, well done! Angus Link to comment Share on other sites More sharing options...
Astrocookie Posted April 10, 2013 Author Share Posted April 10, 2013 Thanks guys :-) Have a good day Link to comment Share on other sites More sharing options...
Craig Posted April 10, 2013 Share Posted April 10, 2013 Bad? Hell no, I wish I could accomplish that! Link to comment Share on other sites More sharing options...
Perkil8r Posted April 10, 2013 Share Posted April 10, 2013 Nice shot. It's not an easy target. I thought it would be really simple but soon found out once I had all the data that it was tricky to get it stacked in a way that looked pleasing, and then even harder to process it to bring it out without over doing some bits but just enough so other parts weren't left behind. You've done a good job Link to comment Share on other sites More sharing options...
Astrocookie Posted April 10, 2013 Author Share Posted April 10, 2013 Cheers Craig. Nice to know I'm finally heading in the right direction with my imaging. Considering its with a self build guiding system which I am chatting about on Friday unless the weather helps me out and it stays clear. Paul Link to comment Share on other sites More sharing options...
Astrocookie Posted April 10, 2013 Author Share Posted April 10, 2013 Thanks Mike. Yes. I know what you mean. I wish I had taken subs over a longer period of time. I think stacking with just the comet as reference looks great with star trails but I wasn't getting long enough trails so I opted for stacking with both comet and stars as reference. Just starting to learn what works and doesn't in PS to enhance the shot I still think I am perhaps over working them a bit. Paul Link to comment Share on other sites More sharing options...
Astrocookie Posted April 10, 2013 Author Share Posted April 10, 2013 Mike. Have you got any images available to look at? Cheers Paul Link to comment Share on other sites More sharing options...
Perkil8r Posted April 10, 2013 Share Posted April 10, 2013 This is the only one I was happy with: http://www.eastmidlandsstargazers.org.uk/topic/4559-panstarrs-c2011-l4-as-shot-atop-the-belper-glacier-050413/ I don't think you have overworked it, but possibly tried too hard to make the sky black? Don't be afraid to have the sky a dark grey, it's not actually black up there afterall Link to comment Share on other sites More sharing options...
Astrocookie Posted April 10, 2013 Author Share Posted April 10, 2013 Cheers Mike You're right. I did try to get the sky Black. I like a nice contrasty image but yes it was at the expense of detail. I had to do a bit of 'clone work' too due to lots of dirty rings on the image. I thought it might be dirt on the camera sensor but it looks fine. (waiting for cleaning pads) I have noticed what looks like grease spots on the telescope lens when it dews up. I there any advice on any of the forums about cleaning refractor lenses. (I was thinking of using the sensor cleaning pads) cheers Paul Link to comment Share on other sites More sharing options...
Perkil8r Posted April 10, 2013 Share Posted April 10, 2013 I've not come across anything that springs to mind regarding the cleaning of Frac lenses. Philjay is your man for advice though, he is somewhat of a frac restoration guru. Flats may help you though? But if you are imaging with any dew on there you are going to be compromising your image from the outset. If you haven't got any already, consider getting some dew prevention, even a camping mat dew shield will help a lot if you can't stretch to dew bands, controllers and the such. Link to comment Share on other sites More sharing options...
philjay Posted April 11, 2013 Share Posted April 11, 2013 I use just ordinary lens cleaning fluid and tissues but muck on your objective wont show up as artifacts on the image, it'll just generally degrade the image when it gets too bad. I should look elsewhere in your imaging train, sensor, filter, diagonal; if used, generally stuff nearest the camera. If you cant find the culprit, flats as Mike says are the answer, they help me a lot with my mucky gear Link to comment Share on other sites More sharing options...
Astrocookie Posted April 11, 2013 Author Share Posted April 11, 2013 Cheers Phil. I've got some cleaning pads and fluid on order. I'll give it a go. Are you at Wymeswold tomorrow? Link to comment Share on other sites More sharing options...
Astrocookie Posted April 11, 2013 Author Share Posted April 11, 2013 (edited) Here's an example of the opaque black spots on my images. I use the same amount of flats and darks as subs but the blobs still appear on the final image,!!! Edited April 11, 2013 by Astrocookie Link to comment Share on other sites More sharing options...
Perkil8r Posted April 11, 2013 Share Posted April 11, 2013 (edited) There looks to be a lot of vignetting there. Can you post up one of your flats? It might be that your flats are either not helping or possibly harming the final image. I'm lucky that I've never seemed to have any trouble with my flats but a lot of people struggle with them. As for the opaque black blobs, do you process levels and curves in Photoshop? Also I assume you are shooting in RAW as opposed to Jpeg? RAW is a lot better as it doesn't compress the image which can lose valuable data. Edited April 11, 2013 by Perkil8r Link to comment Share on other sites More sharing options...
Astrocookie Posted April 12, 2013 Author Share Posted April 12, 2013 Hopefully we will be able to discuss tonight ;-) Link to comment Share on other sites More sharing options...
Perkil8r Posted April 13, 2013 Share Posted April 13, 2013 Paul, Sorry I didn't get chance to talk to you at the meet, to be honest I didn't make the connection can you post up one of your flats? Link to comment Share on other sites More sharing options...
Astrocookie Posted April 14, 2013 Author Share Posted April 14, 2013 Oh. I didn't think you we're there :0) I'm pretty sure in getting my flats wrong. I bring my kit in after a nights work and put a cricket top over the top of my lens, aim the scope at a white wall and snap away, same ISO and exposure that I uses for the subs. The result is a completely bright white uniform image. What is the correct method.??? Cheers Paul Ps: did we speak at all at the Wymeswold gig? I'm just trying to place you! (Faces to names) Link to comment Share on other sites More sharing options...
Perkil8r Posted April 14, 2013 Share Posted April 14, 2013 Ah...... We have a strong clue as to what's going wrong Your flats are over exposed (in most probability) You have a 350d the same as me if I recall? In which case, set up as you describe. When you take the flat frames you will in most cases need to knock the exposure lengths right back. I take mine using the laptop screen with a completely white image but the method will be the same. Take a short exposure, say half a second, review the image on the camera and look at the historgram. What you are aiming for is the big peak on the historgram to be roughly in the center. Disgard any that you do whilst setting up so to speak so that you don't use them by mistake, if your historgram was too far to the right, shorten the exposure, too far to the left then lengthen. It doesn't need to be bang in the middle, I aim anywhere in the middle third if that makes sense? Give that a go and see how you get on. Darks are the same length as your subs but with the lens cap on, flats need to be neither under nor over exposed as they are going to help the stacking software figure out where dust, dirt and so on is in the chain and also how the sensor is being illuminated to help get rid of vignetting. By over exposing it will think the sensor is being illuminated fully across the whole thing which will cause the vignetting you are getting in some of your images. Have a play and let us know how you get on. . Link to comment Share on other sites More sharing options...
Astrocookie Posted April 14, 2013 Author Share Posted April 14, 2013 Top man Mike You've hit the nail on the head there. I was wondering what the point of a flat was when looking at mine !!!! Darks are OK. I took them immediately after the subs with the cap on as you say. I suppose it's too late to take flats now as I have dusted the sensor since. I'll still have a play later though against my white wall just to get the histogram right. Thanks again. (Were you the one who put their hand up when I asked who does autoguiding????? lol) Link to comment Share on other sites More sharing options...
Guest peter shah Posted April 14, 2013 Share Posted April 14, 2013 a super shot of it, nice FOV Link to comment Share on other sites More sharing options...
Perkil8r Posted April 14, 2013 Share Posted April 14, 2013 Top man Mike You've hit the nail on the head there. I was wondering what the point of a flat was when looking at mine !!!! Darks are OK. I took them immediately after the subs with the cap on as you say. I suppose it's too late to take flats now as I have dusted the sensor since. I'll still have a play later though against my white wall just to get the histogram right. Thanks again. (Were you the one who put their hand up when I asked who does autoguiding????? lol) Not me, I don't do guiding, I just have an OCD for polar alignment and do 5 mins unguided on the eq5 You're right in that your flats will be wrong now if you've cleaned the chip, but it will still help with the vignetting. It will be far from ideal though, but have a go, it's not like it will break anything to try Link to comment Share on other sites More sharing options...
Astrocookie Posted April 17, 2013 Author Share Posted April 17, 2013 http://s1341.photobucket.com/user/Astrocookie/media/histogram_Flat_zps21f5ea1d.jpg.html Is this the sort of histogram i'm after for my flats???? Link to comment Share on other sites More sharing options...
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