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Posts posted by Prolifics

  1. On 10/07/2019 at 18:29, michael8554 said:

    If your camera and guidescope aren't separated between sessions the focus and hence HFD shouldn't change, and 2.2 is great. 

    If you're not separating them, then are you guiding on saturated stars sometimes (flat top to star profile).? 

    Auto selected stars don't do that. 


    Hi Michael Found 20 minutes of gaps between clouds tonight done all the things you mentioned and with hazy clouds was getting between 40 and 90 snr on quite small stars. Thats a big improvement and I think will solve the issue and be even higher without clouds. I also loaded up sharpcap and turned on polar align. I have never had more than 9 stars detected it was at 19 tonight :)

    Oh and that was on gain 1x using the ascom altair driver. Did not get chance to up the gain clouds rushed in fast!


    Thanks for all your help in this matter :)


    Regards David

  2. 21 minutes ago, michael8554 said:

    It's HFD, and below 3 would be great, but minimum might be higher and would be the best you can get.

    You can check your current HFD in a PHD2 guidelog, search the text file for HFD. 


    Many thanks that was the next question :) I have been focusing on objects about 40 m away and it works fine so not sure what the problem is. I am using the adapter that came with the guidecam so you can get focus.

  3. Hi having a few issues with my guiding and focus.

    Just a couple of questions especially if you have one of these guiding scopes.

    1) Which driver should I use Altair or ascom altair? I am using eqascom setup.

    2) What gain should I use on the guide camera as a ballpark? Some say gain 1x (lowest) if you can set in ascom if using the Altair Ascom driver.


    Finally a link to my actual guidescope. I have also in phd2 software set the noise reduction to 2 x 2 mean as recommended by several people.



    Many thanks


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  5. Managed to get out last night. Spent alot of time getting the autofocuser working as I wanted it. I ended up with only a couple of hours so I tried M13. With the filter wheel the right way around :)

    I have no photshop skills as you can see. Took me about 10 minutes to get something that qualifies as identifiable. Flats seem to have worked a lot better this time. Be pleased to have some input please as this is a minefield in learning which I love.

    Guiding averaged 0.85 in PHD2
    HWFM 1.37 and HDR 0.50 using ZWO EAF 

    30 x 1 min Luminace
    15 x 1 Minute Red
    15 x 1 Minute Green
    15 x 1 Minute Blue

    20 Darks
    20 Flats @25000 ADU


    PS. I have some slightly oval stars to the edges are these caused by not having a Flatener/Focul reducer? I should have cropped the picture but left it as is.




    M13 test 1.jpg

  6. Another major fix I have just made which I would have not picked up on if I wasn't scouring the forums. My EFW zwo wheel was on the wrong way. Which means the gap between the camera lens and the filter was 8.5mm instead of 2.4mm approx. Plus it also meant the filters were on the wrong way. I reversed it all and the camera is on the correct side of the filter wheel now and the screw threads on the filters are facing the camera.

    Which accounts for those big black reflection filterwheel size circles on my images :) Should also reduce vigneting sigificantly!

     I just purchased and installed the EAF ZWO Auto focuser and is working like a dream. Can't wait to get back out hopefully this weekend for another try. Will post end results. 


    Regards David

  7. My flat panel should arrive tomorrow. In APT the ADU is set as default at 20,000 should I leave it there or change it. Some people have mentioned 12,000 is better? Or use a histogram and do it that way?

    I would like a good start to my flats probably take 40 per filter.


    Regards David


  8. 1 minute ago, Adreneline said:

    Sorry about that - it's getting late and I wasn't concentrating on what you wrote regarding the flats.

    You can take darks at any convenient time as long as they are at the same temperature, exposure, gain and offset.

    I usually take my flats the following morning - I'm usually too tired to do it at the end of an imaging session. I can't see it being an issue providing you don't disturb the imaging train at all. If dust bunnies move they can often be reduced during processing. The flats will really help with the vignetting.

    It's all going in the right direction and looking good!

    Apologies again for not registering the lack of flats and darks.


    Hi again Adrian


    No problem I do that a lot myself :) I think I got the PHD2 tracking great and the focus acceptable. Just need a clear night and try with flats and darks. A never ending learning process thats why I am enjoying it so much :)

    I usually stay up until i go unconscious :( Then I realise I need to bring the scope and mount in as well as all the wires. I need to organize myself and finish 45 minutes earlier so I can take the flats just before I fall to the ground :)

    Have a good sleep.

    • Like 1

  9. 8 minutes ago, Adreneline said:

    Hi David,

    Well I've had a go.

    On the positive side this is a really well framed image of M101. I would say you have definitely improved the focus issues you were experiencing. Don't forget that achievable absolute FWHM is dependent on so many things and trying to achieve some magic low value on any given night is pointless. In my view you need to achieve the lowest value you can for a given filter - they will all vary. With my ED80DS I find that blue never focusses as well as red, green or luminance. Many of my rgb images suffer from blue bloat around the stars.

    On the negative side the flats are clearly not doing what they should be doing as all the masters exhibit severe vignetting and evidence of dust bunnies; I would suggest the latter are on the filters as they move from filter to filter.

    Having said that I have done my best (I'm sure others could do better) to reduce the effect of vignetting and dust bunnies as much as possible, probably at the expense of some of the outer arms of M101.


    I've processed pretty much as before but this time I also used the Luminance image as a 'Lighten' layer in Photoshop at about 45% opacity.

    Can you post one of the master flats - anyone - so I can have a look please.



    Hi Adrian 


    Thanks again for all your help. As I stated above there is no flats or darks in this image. I did not want to complicate matters and wanted to try and fix focus issues etc. Would you suggest next to use some flats and darks taken on the same evening as I take some exposures? I also am waiting on my light panel to arrive. So seeing there are no darks or flats in these stacked images I think they have turned out ok ish :) This is still my 2nd ever object I have imaged. Next to the flats and darks. 

    My theory on Darks is to take:

    same length of Exposure as lights
    Same Gain and offset as Lights
    Complete darkness and temperature as of lights taken.

    Flats will need experimenting with via APT Flats maker and a suitable Light source.


    Also Using FWHM in Sharpcap making the square reitcle smaller over a star also brings down the Focus number :)


    Also PHD2 guiding on my gear modded eq6 pro was 0.51 over 1.5 hours. There was a time that for 35 minutes no corrections to the graphs were ever made. I though that this was an error but it was guiding at 0.23 (total error) then :)

    I run Phd2 guiding right out of the box as to say and don't even bother with the guiding assistant.



    Kindest regards David




  10. 16 hours ago, Adreneline said:

    Good luck David! Hope you get some good results tonight; not easy on these short nights when Mr Moon is up and about but it's still a good opportunity to sort out a few niggling issues and problems.

    Next time I get my gear out I will be sure to screenshot the focussing results I get with SharpCap for comparison.

    Looking forward to seeing the results of tonights endeavours!


    Hi Adrian


    Your right about moon and short time to aquire an image. I decided to take 20 x 1 minute exposures in LRGB I stacked them in DSS without dark or flats. I wanted to eliminate any problems.

    Link not M81  https://www.dropbox.com/sh/skqoxrbe5huosg4/AAAdQ_UEP0XsX0S0b6oBPiiKa?dl=0

    Firstly I wanted to see if the focus was better and if I eliminated those red problems. Please give me your views if you have any time on your hands to download the new data of a new object. I noticed I have no claw marks now (probably caused by bad flats). But I still see what looks like coin size circles around SW of centre. Are these from the filter wheel or dirt? Scope is brand new nearly.

    When I load my masters into PS they are RGB/32 bit. I saved them in DSS as 16 bit not sure either why they are not greyscale when I load them in?


    Look forward to your honest opinions :)


    Kindest regards Davd




  11. On 18/05/2019 at 13:27, Adreneline said:

    From purely personal experience I have found SGP hdr focussing not to yield good or consistent results. I have wasted so much time trying to get autofocus to work that I now focus manually, albeit with a stepper motor focus unit - I go and stand outside and use SharpCap on a laptop - five minutes (if that) and I'm done.

    As for SharpCap I've decided £10 year is money well spent; it is constantly being updated and improved. I use both the FWHM Measurement and Bahtinov Mask options and find I get very good results.

    Solving problems is all part of the fun! Not sure you ever reach the point where you've solved 'em all though!

    Good luck.



    Hi Adrian 


    Out with the scope used Sharpcap and used the Bahtanov mask and focused exactly the middle spike to the centre. Then went to  FWHM Measurement mode in Sharpcap showed as 5.6 I used the fine focuser and got the bars down to low yellow average 3.3. It won't go any lower than that. 3.3 Obviously an improvement over 5.6 whcih is where my setting were on my first upload.


    I also found huge movement in my EQ6 Pro mount on the dovetail head of over 6mm :) Tightened the 3 tap screws and re-aligned for home park position.


    So tonight I aim to do some 2 minute exposures. I will let you know how they turn out if they look OK i'll upload them so you can take a look. I think I am heading in the right direction :) Thank you for all your valuable help!


    Kindest regards David

    • Like 1

  12. 7 minutes ago, Adreneline said:

    Hi David,

    I've used a BM with and without success. I've recently started using SharpCap (£10 per year) to help me focus with a preference for FWHM measurements but success depends on so many things, including the 'seeing'.

    I do pretty much the same but I have had more success using a uniform light source; I use my iPad running a lightbox type app and get very consistent results; the flats also work!

    Well done you! I'd be happy to have that average over an imaging session.

    tiff is just fine but I wonder whether it is DSS that decided to save as rgb rather than greyscale. I presume you have checked it is expecting to process mono images - it's in one of the Settings menus somewhere - can't exactly remember where though.

    As for the artefacts I'm really not sure what to say - it doesn't look like dew to me. It may be the flats just not doing their job properly.

    Another thing I would say is that the advice seems to be not to use Bias with a ASI1600 Pro. Rightly or wrongly (but it seems to work for me) I've started using flats + dark + dark-flats (instead of bias). If I'm doing something very wrong then hopefully someone will pop up and put me straight! Dark-flats are exposures taken with exactly the same exposure times as the corresponding flats but with the lens cap on - hence dark! You can use them in DSS.

    I would have another bash at taking your flats. I know dust bunnies may have moved but it might correct the vignetting problems you are experiencing. People use a variety of white light panels; I tried using one of the Huion panels but found it gave me severe 'banding' when used with both my dslr and ccd's so I gave up.



    I have Sharpcap as it comes free with my Altair GPcam2 aor130 but I first started using SGP for focus with the mask by right clicking picture and using the HDR option on the menu. Not sure how to do that with Sharpcap will take a look later. But if i change camera it will de-license itself as its only a full version with the Guidecam above selected. I use Sharpcap for my Polar Alignment.

    I will investigate in a better light source for my flats some sort of evenly lit panel that has different brightness options and try the flats again. I will stop the bias frames from now on. 

    I will also investigate options in DSS so they don't save as RGB and ssave as Greyscale.

    After that lot is sorted I may see some of the problems go away :)





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