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Cosmic Geoff

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Posts posted by Cosmic Geoff

  1. 2 hours ago, happy-kat said:

    Is there a fits file we could access to play with? 

    Here's one, for M57.

    Header data follows:

    SIMPLE  =                    T / file does conform to FITS standard
    BITPIX  =                   16 / number of bits per data pixel
    NAXIS   =                    3 / number of data axes
    NAXIS1  =                 1080 / length of data axis 1
    NAXIS2  =                 1920 / length of data axis 2
    NAXIS3  =                    3 / length of data axis 3
    EXTEND  =                    T / FITS dataset may contain extensions
    COMMENT   FITS (Flexible Image Transport System) format is defined in 'Astronomy
    COMMENT   and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H
    BZERO   =                32768 / offset data range to that of unsigned short
    BSCALE  =                    1 / default scaling factor
    CREATOR = 'ZWO SeestarS50'     / Capture software
    XORGSUBF=                    0 / Subframe X position in binned pixels
    YORGSUBF=                    0 / Subframe Y position in binned pixels
    FOCALLEN=                  250 / Focal length of telescope in mm
    XBINNING=                    1 / Camera X Bin
    YBINNING=                    1 / Camera Y Bin
    CCDXBIN =                    1 / Camera X Bin
    CCDYBIN =                    1 / Camera Y Bin
    XPIXSZ  =     2.90000009536743 / pixel size in microns (with binning)
    YPIXSZ  =     2.90000009536743 / pixel size in microns (with binning)
    IMAGETYP= 'Light   '           / Type of image
    STACKCNT=                   11 / Stack frames
    EXPOSURE=                  10. / Exposure time in seconds
    EXPTIME =                  10. / Exposure time in seconds
    RA      =            300.15417 / Object Right Ascension in degrees
    DEC     =            22.794444 / Object Declination in degrees
    DATE-OBS= '2023-09-15T21:17:52.226397' / Image created time
    FILTER  = 'IR      '           / Filter used when taking image
    INSTRUME= 'ZWO ASI462MC'       / Camera model
    BAYERPAT= 'GRBG    '           / Bayer pattern
    GAIN    =                   80 / Gain Value
    FOCUSPOS=                 1617 / Focuser position in steps
    CTYPE1  = 'RA---TAN-SIP'       / TAN (gnomic) projection + SIP distortions
    CTYPE2  = 'DEC--TAN-SIP'       / TAN (gnomic) projection + SIP distortions
    CRVAL1  =        300.080461534 / RA  of reference point
    CRVAL2  =        22.7485782229 / DEC of reference point
    CRPIX1  =        287.141927719 / X reference pixel
    CRPIX2  =        878.079833984 / Y reference pixel
    CD1_1   =   -0.000640259548805 / Transformation matrix
    CD1_2   =   -0.000155699886841 / no comment
    CD2_1   =    0.000155330795079 / no comment
    CD2_2   =   -0.000640007144967 / no comment
    A_ORDER =                    2 / Polynomial order, axis 1
    B_ORDER =                    2 / Polynomial order, axis 2
    AP_ORDER=                    2 / Inv polynomial order, axis 1
    BP_ORDER=                    2 / Inv polynomial order, axis 2
    A_0_0   =                    0 / no comment
    A_0_1   =                    0 / no comment
    A_0_2   =   -2.72399212086E-07 / no comment
    A_1_0   =                    0 / no comment
    A_1_1   =    3.15089321972E-07 / no comment
    A_2_0   =   -4.82895905823E-08 / no comment
    B_0_0   =                    0 / no comment
    B_0_1   =                    0 / no comment
    B_0_2   =    1.01487242366E-07 / no comment
    B_1_0   =                    0 / no comment
    B_1_1   =    5.82881418145E-07 / no comment
    B_2_0   =   -5.54562671461E-07 / no comment
    AP_0_0  =    2.36061654639E-05 / no comment
    AP_0_1  =    -5.6197243827E-08 / no comment
    AP_0_2  =    2.72324015254E-07 / no comment
    AP_1_0  =   -6.89411248193E-08 / no comment
    AP_1_1  =    -3.1489293254E-07 / no comment
    AP_2_0  =     4.8196817389E-08 / no comment
    BP_0_0  =   -3.84631989892E-05 / no comment
    BP_0_1  =   -1.12292551537E-07 / no comment
    BP_0_2  =    -1.0135344279E-07 / no comment
    BP_1_0  =    2.21043408709E-07 / no comment
    BP_1_1  =   -5.82848681282E-07 / no comment
    BP_2_0  =    5.54345404161E-07 / no comment
    IMAGEW  =                 1080 / Image width,  in pixels.
    IMAGEH  =                 1920 / Image height, in pixels.
    END

    Stacked_M 57_10.0s_20230915-221030.fit

    • Thanks 1
  2. Briefly, I'll explain that the new ZWO Seestar S50 delivers two kinds of output files:

    1) A high-resolution .jpeg delivered to the controlling smartphone, and maybe onwards via the Cloud to your image processing PC.  All so simple a child could do it.  An increase in the contrast brings out more detail.

    2) A FITS file (accompanied by a low-res .jpg thumbnail) stored in the S50. This can readily be extracted to a PC or laptop via a file browser.  But what is one supposed to do with it?  Apparently the FITS file contains the stacked images, and needs to be stacked by a program e.g. Siril or Deep Sky Stacker, before being processed in one's program of choice (e.g. GIMP).

    I have looked at Youtube tutorials, and downloaded various bits of software, but my small brain can't make sense of any of it. 

    One  tutorial recommended using Siril using a particular script, which turned out not to be in the default installation, and which I could not find to download.  Fail 1

    Sirilic was suggested, which seems to involve signing up to GitHub. And not finding anything to download. Fail 2  

    I downloaded Deep Sky Stacker (which I managed to try out a couple of years ago on another PC)  but got nowhere with the S50 FITS. Fail 3

    Isn't there a SIMPLE way of doing this?

  3. I have a SLT mount, but I would appreciate a photo (preferably annotated) of the faulty area in case I can help.

    There is a slip clutch and on one occasion I removed the dovetail clamp screw so I could access the large nut and adjust it.  I have not had to touch it since.

    IIRC there are various preparations, e.g. Loctite, used to discourage nuts and bolts from unscrewing.

  4. I received the SS50 a few days ago and on Friday I was able to take it on a dark skies weekend and give it its 'first light'. 

    First impressions are that it is extremely easy to use, except that the app is not that easy to use, and in total darkness it is impossible to see where the little black device is pointing itself - whether somebody is stood in front of it, or if it is pointing at a tree. 

    The aiming process (entirely automatic) is not that quick and can take a minute or more while the device plate-solves and re-aims.   One has to initiate the actual stacked image taking manually.   Once taken, the images look good on the smartphone and if you have setup with icloud will copy to your image processing computer without further intervention.

    Here, I found that an increase in contrast brings up nebulae in the iphone image nicely.

    Images are also stored in the SS50 itself and this is a different story. First, these are not the same images as sent to the smartphone. There is a low-resolution jpg which is essentially a thumbnail, and a high-resolution FITS file.

    A big GOTCHA here for anyone who is used to using Sharpcap for live-stacking and saving a file.  This is apparently a different variety of FITs file and needs to be stacked in Deep Sky Stacker or Siril, before processing in (e.g.) GIMP.   It took me a while to realise this, following a search online. So I downloaded and installed Siril, and tried to follow an instructional video for processing SS50 FITS that I found on Youtube.

    Turns out after further head-scratching that this involves a script file that has to be downloaded separately because it's not in my Siril.  Could not find script, and gave up.

    TBF I'm not impressed with this.  It's really easy for any newbie to use this device, but if you want to process the saved images, you are expected to instantly transform into Image Processing Expert?

    • Like 2
  5. 25 minutes ago, Mark2022 said:

    I've never yet seen a night where, on screen during capture, I can see the detail (even slightly) that Kon has in his photos.

    You won't see much detail on the live screen during capture, compared with the final processed result.  Typically you can see a cloud belt or two, and the Great Red Spot if it's on the Earth-facing side.  

    I'd hesitate to cast aspersions on your camera, but I could not find any reviews comparing it with the ZWO range. 

    Have you checked the collimation of your Meade?  I thought my CPC800 was okay, till I did a side-by-side collimation star test with another SCT, tweaked it and noted an immediate improvement in the imaging results.  Clearly the collimation is critical - if it is noticeably off during general viewing then it's really bad.

    • Like 1
  6. 11 hours ago, Mark2022 said:

    Lots of things to change.  I'm just approaching this step by step to understand, if possible, what are the basic things I need to concentrate on to improve the most. Then next step and next step after that. I'll experiment with everything of course but the issue is - as you know - we get so very few good capture nights to 'waste' on experimenting when we want to capture stuff. Hence why I turn to those of you who can help, give suggestions and  advice.

    You need to adopt a systematic approach, instead of searching for a magic bullet.

    Choose the right observing time, get the focus right, get the video recorded right. Then choose a set of tools (as used by others) and use them systematically, keeping a note of what settings you have used.  If you keep the source videos filed by date, you can go back at any time and try re-processing with different settings, or different tools. Sort processed files in sub-directories.

    If the source videos are no good, the final results won't be either.

    • Like 1
  7. I had a quick play with one of your Saturn files. I am not clear what you have done here, as I don't use PIPP for planetary at all in most cases.  I loaded it into Registax as if it was a file pre-processed in Autostakkert from a video.  The colour balance was awful, with hardly any blue.  I have sharpened it up a bit but it still looks bad.  Oddly there is hardly any noise.

    TBH, given the likely value of the other gear involved, it would not be overkill to buy a used Win10 business laptop, and use it for image capture and processing. Then you can use all the popular astro programs, e.g  Sharpcap > .ser video > Autostakkert >tif > Registax.

    If you reduce your ROI that will cut your raw file size, increase capture rate, and avoid filling your storage with data representing black sky.

    saturn prime focus__000002__22-53-34__data_pipp_____100r_48T_6738reg.jpg

    • Like 1
  8. It's just attention to detail:  do the procedures other people did and check you have the right f-ratio, ADC for low planets,  accurate focus (check again if you disturb anything or the scope temperature changes), enough frames (I usually do 5000), and cross fingers for some decent seeing.  

    A smaller ROI means you can up the frame rate, and increasing the gain means you can reduce the exposure.  Use the Sharpcap histogram to set a suitable exposure.

    • Like 1
  9. On 05/09/2023 at 18:30, squipper said:

    so  what's the type of scope for planets  a  dob or newt or a frak  .

    Any type of scope can be used for planetary viewing so long as it's not a widefield achromat, e.g you could use a Newtonian, a Maksutov, a SCT , or a long focus refractor.  But it should have as large an aperture as you can practically provide.   These scope types all differ in aperture per ££, usability and weight. Some people will claim that some types perform slightly better than others of the same aperture, but you might not see the difference yourself. You also have to mount it.  You could get by with an all-manual mount, but the ability to power track is a great convenience if using higher magnification, and GoTo is a time saver for finding faint planets e.g. Uranus and Neptune, and for finding planets in daylight (yes you can!).

    If you intend to image planets, the same remarks apply, except that a powered or GoTo mount becomes even more of an advantage. 

  10. 42 minutes ago, bosun21 said:

    I would think that sometime in the future they will come out with an update to allow EQ mode. Something like what we have with the SW GTi.

    We shall see. However, the Seestar S50 is designed to stack a series of short images to build up a composite image. (EAA)

    I have done the same using both alt-azimuth mounts and an equatorial mount, and the only notable drawback of using an alt-azimuth mount is that a notable effect of field rotation builds up around the edges of the image and has to be cropped off.  The stacked portions of the image are unaffected.  The effect was demonstrated in one of the Seestar S50 Youtube review videos I watched.

    • Like 1
  11. 6 minutes ago, LDW1 said:

    If you don't upgrade think of the $'s you save and the fun you miss, you can't have one without the other. It just leads to more whining, more cursing, lol !  Good Luck !    PS:  And maybe restless sleep.

    We see where you are coming from and we get you. But not everybody wants to spend money chasing the latest shiny thing, when the old stuff still works.  I don't. for instance, need a 4K TV when my HD TV still works, and I don't need to spend tens of thousands of pounds on a new electric car, when my old petrol car still runs just fine and gets me around. 

    • Like 4
  12. 2 minutes ago, LDW1 said:

    10 years old !  What exactly are you expecting, hopeing for 10 years later operating this revolutionary piece of gear ie SS50 ?  Its always been upgrade this and now upgrade that, lol !

    My 22 year old Japanese car still works fine, so a 10 year old tablet ought to work OK IMHO.  The rapid obsolescence of electronic devices, usually because of software updates, is annoying.

    • Like 2
  13. Just received my Seestar 50 and have been checking it out.  If you have been looking at the online ZWO spec and the Youtube videos, you may know it comes in a nice carry case, with a tripod (which feels reassuringly solid), a USB lead for charging, etc (mine was 50% charged on arrival) a solar filter, and quickstart instruction leaflet.  Apparently the device includes a dual-band light pollution filter (!).

    I downloaded the iphone app and got the device started without any bother, except that the app is about as intuitive to use as iphone apps usually are (i.e. it's not).  I aimed it out of the window and got it to auto-focus on some bricks in middle distance. Took photo. The slider to shut the S50 down is at the bottom of the screen (yes, it's hidden).

    I tried loading the Android app to my 10 year old Nexus 7 tablet, but did not get anywhere.  Terribly sluggish, nothing much happens when I tapped download. (And it's not in the Google Play store, tried that.) Maybe I just shouldn't bother, but the Nexus 6 has a bigger screen. The Android APK (about 680mb) is downloading to my PC just fine, so it's clearly a tablet issue.

    • Like 1
  14. I don't think that drift of the image during exposure was the problem.  I have whole sets of these Moon images all clipped on the same side.  The video was 1000 frames long in this case with an exposure of about 1.5ms, so the whole thing would have taken about 2 secs to shoot.  I ran through one of the vids on .ser player and it didn't drift. The CPC800 tracks well.

    Also, the same video processed with Registax alone gives a full image.

    I did wonder if the AS!3 is chopping off parts of the image that are too bright or too dark?

  15. I now use Autostakkert + Registax to process my lunar and planetary images, and my main interest is with the planets.  I noticed yesterday that the Autostakkert process is cropping the full frames for some reason.  Below I have shown a frame  from the  .ser video (1000 frames, 1920x2080, needs horizontal flip) TOP,  the .tif output from AS!3 BOTTOM,  the final processed AS!3/Registax output THIRD - (note the blank area and clipping), and the output using Registax for all stages of processing SECOND.  The missing areas show up in red in the AS!3 image if I pan it in the app. What is happening here?

    Moon03-25-37still.jpg

    Moon03_25_37R.jpg

    Moon03_25_37AS.jpg

    03_25_37Z__IR_limit000000-005000_lapl5_ap2251.tif

  16. I should think it likely that your handset would be compatible with the 90GT if reprogrammed.   It's a Nexstar+ and apparently that's what the GT is sold with. 

    If you look on nexstarsite.com, it says that if your GT mount has version 5 firmware, then it's the later model and should be used with a Nexstar+ handset, and the handset firmware is version 5 as used for the 4/5 SE mount.

    I don't know if you are a technically adept person.  If the detail of reprogramming the handset is over your head, your best course would be to sell the mount and handset on, and start again.

     

  17. I see that the 90GT is an alt-azimuth mount (it looks like an earlier version of the SLT mount), and the AVX is an equatorial mount, so that combination definitely won't work.   My point remains, that it may be possible to reprogram the handset with alt-azimuth firmware that works with the 90GT.   Is the handset a Nexstar* (older) or a Nexstar+ ?

    I found a quick setup manual for the 90GT online and it seems to show the Nexstar+ handset, but that doesn't mean a Nexstar* handset wouldn't work.

    As an aside, I have found that I have three different types of Celestron handset, and I have three different Celestron mounts, and I can swap the handsets around at will, BUT all are alt-azimuth

    • Like 1
  18. It's possible that if you reprogram the handset with software that's compatible with the 90 GT, it will then work.   This may not be a task for the faint-hearted, as you may have to buy cables or USB-serial adapter, download and install various bits of software, and then download the software for the handset. 

    Last time I did this, I updated the software on a Nexstar* (not Nexstar+)  for a Celestron C8 SE.  On the first attempt, I got it wrong and downloaded the latest software for an equatorial mount (as I presently saw on the handset), and had to start the update process over and select the right software (for alt-azimuth).  

    I also had to hunt around for an older installer, as the preferred one, Celestron's CFM, wouldn't work for some reason.

    If you visit nexstarsite.com, you may be able to figure out whether your mount and handset are potentially compatible. 

    • Like 1
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