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Posts posted by Prolifics

  1. Hi Sean


    Thanks for your reply. Each colour is stacked and aligned by itself. But each colour has drift like you said of a few millimeters. Isn't there a program that aligns your LRG and B data after they are stacked?

    For an example say I take 30 exposures of Lrgb 1 night then decide to finish it in 2 months time. They are going to be slightly different.


    Here are examples of my RGBL data as you can see the stars have rotated slightly. My mount has just been hyptertuned and was guiding at 0.40 average in PHD2. Polar aligned with Sharpcap to 00.08 on each or better.

    L 60x 1 Min
    R 30 x 1 Min
    G 30 x 1 Min
    B 30 x 1 Min
    30 Flats of each 
    60 Darks








    Finally RGB when put in there channels without luminance. Now you can see the green and blue where we arent alligned with each other.





    Regards David

  2. Hi guys

    I am suffering to being able to understand something as a new imager.

    I imaged an object that went past meridian and my mount done a automatic meridian flip but from then on the pictures were upside down. Using APT
    I put them in deepsky stacker and made a reference frame for each of LRGB images and got them all to stack fine and saved them as L.tiff R.tiff G.tiff and B.tiff. Each colour are aligned fine. (now each colour are all the same way up)
    However when i put them in photoshop when I make an RGB channel and paste each one in I get red and green dots in the RGB master which shows although each colour are aligned they are not aligned with each other.

    So question is when I have stacked each LRGB although individiually they are stacked fine how do I get them to stack with each other. Stars are slightly missaligned in each colour to each other.

    Very hard to describe but hopefully you understand.


    Thanks in Advance David






  3. 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

  4. 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.

  5. 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


  6. MDS-C11- MDS Series Dovetail Bar for Celestron 11″ SCT Telescope


    Fits all Celestron 11″ OTA’s including CPC and HD models. Curved radius blocks and mounting hardware include. Uses existing mounting holes in OTA. 18″ long, 1.5″ wide, .625″ thick, Wt.16 oz.

    R100- 100 mm Adjustable Rings with Delrin Tipped Thumb Screws



    £89 for both Collection Only.







  7. 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

    • Like 1

  8. 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

  9. 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
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