michael8554

To see if that is correctly installed, go to Windows Device Manager Look for a instance of a COM port, and note the COM Port number for EQMOD and PHD2. If the COM port has a yellow error icon, the installation isn't complete. Which Guidecam do you have ? If it's another ZWO brand camera, then it's all too easy to connect to the ASI2600MM-Pro cooled camera by mistake. Try during the day, a 1 second daylight exposure should flood the screen in PHD2, then with your hand over the scope aperture the screen should go black. Can I assume from your expert's setup that this isn't your first rodeo, you are familiar with PHD2 ? Michael

An interesting link Starflyer, I will digest that TAE theory. So Brad, a MinMo of 0.50 pixels will be equivalent to this many arcsecs: Your guide image scale in arcsecs/pixel x 0.50 pixels. Michael

Quite possibly. But you need to look at a GuideLog with the Log Viewer, to see how many arcsecs the 0.50 setting actually equates to. Michael

The "Leap before you Look " school eh ? Might be something helpful in these: http://stargazerslounge.com/topic/135260-127-mak-motor-drive-focuser/ http://www.tanstaafl.co.uk/2012/02/skywatcher-127-mak-focuser-motor-drive-conversion/ With the OTA pointing skyward you might be able to fish for the focus rod. Be careful handling the OTA now that the mirror is free to slide at speed. Michael

If that works, who cares if it's different to your other mount ? Michael

1) When trying to connect The T-Adapter with the ZWO filter drawer it does not lock in position You'll have to be more specific. The T adapter has a T2 female thread into which the T2 male of the filter drawer screws. When you've screwed those together tightly they're locked. 2) you have 44mm DSLR + 2mm T2 Adapter + 21mm T2 Filter Drawer = 67mm So you need 105mm - 67mm = 38mm of spacers. I'd try 40mm which is 2mm too much, and check the star shapes in the corners of images. With a "normal" 11mm T2 adapter for the DSLR you'd need 29mm, so a 30mm spacer would only be 1mm out. Michael

Looking at the screengrab, RA = 9.80 arcsecs, Dec = 29 arcsecs. Such hugely different figures indicate very poor guiding, resulting in Dec elongation of stars Dec is wobbling at least 8 arcsecs, it looks like it's going to end up way beyond the limit of the vertical scale. And the guiding software is struggling to bring Dec back, taking 8 x exposure secs to correct. Your Dec has a lot of Stiction, so when that pent-up energy is finally released, the mount is catapulted to the other end of the backlash. And all this probably repeats. RA is 300% better, but still poor. So many things could be wrong, with little info on settings to work with. Guide stars look out of focus, HFD = 6.06 is too high. Michael

A quick search came up with a mains adapter that Explore sell for your mount, 12volt 5Amp. And the scope spec says 12V 2Amp. I'd be conservative and go for at least 3Amps. Michael

You could try the Camera Gain "Reset" button in the Camera window, my ASI120MM defaults to 48. Whatever the exposure setting in seconds, when you hit the autoselect button, PHD2 will select a suitably exposed guide star for guiding. Don't manually select a guidestar, leave it to PHD2. Michael

I've always been of the opinion that the #LPF-1 adequately blocks IR, but thinking about it, I was probably just passing on unsupported anecdotal information. Michael

PHD2 isn't an imaging prog, so the display was designed just good enough to display stars. I would use something like SharpCap to give a true indication of the guidescope quality. Your exposure is only 0.5 seconds, up it to 1.5 or 2 seconds and the stars may be good enough for PHD2 to select one when you hit the Loop button. Michael

Dew in the brightness control can dissolve the resistive track, making it open circuit.

Many would recommend to roughly hand-focus the mirror, lock it down to prevent "flop", and use a motorised Crawford-style focuser to fine focus. Michael.

Hi Andy Is there room in your image train for a motorised zero-shift focuser ? Moving the mirror 190mm changes the focal length. Michael

Hi Andy I refocus every night with my permanent pier-mounted system, I don't see any way of avoiding that, it takes very little time. Once you have worked out what spacers are required for each camera, to make them close to parfocal at the same focuser position, all you do is swap and tweak focus. I appreciate your desire to "automate" your swaps, I'm afraid how to do that is more than my pay grade 😆 Michael

Not sure I have understood your descriptions of your focus problems. All your adjustments should be to place each camera sensor 146.05mm back from the rear of the OTA, that's Celestrons' recommended back focus for the C11 Edge HD. Which cameras are you trying to make "parfocal" ? How are you attaching these cameras with the FR, without the FR ? Some images of the setups would help. Camera A and Camera B might have different flange distances, so just swapping cameras without adjusting spacing won't work. If daytime tests won't work, try getting a feel of the focusing on a distant streetlight, or the moon, at night. Michael

After searching I think the OP means a "Celestron Skyprodigy" mount with a 90mm MCT. Move to "Mounts" ? Michael

Your SXVR H16 "rains hot pixels" 😆 Michael

I gather you made a stack of exposures that had round stars ? Then that drift in Dec over time is due to Polar Alignment error. Perfect PA is not possible, so guiding Dec would help. But I don't think your mount has Dec motors ? So get best PA and expose for as long as gives round stars, those subs should stack well. Michael

So which "hot mirror" do you to remove ? The # LPF-1 filter passes the visual band and rejects IR, so this remains in place in a Ha mod. If you remove that and the #LPF-2 filter you have a Full Spectrum mod. The #LPF-2 filter is a visual band filter that partly attenuates the Ha end of the spectrum, so only that one is removed for a Ha mod. Michael

"Removal of the hot mirror really does make the red hit you." To avoid further confusion, AFAIK "Hot Mirror" refers to the IR Filter, which remains in place in a Ha mod ? Michael

Hi Bob Depends on what focal length scope you are going to image with. If it's a long focal length such as an SCT you will need an Off Axis Guider, and a premium sensitive camera such as a Lodestar. If it's a short focal length then a separate guidescope and a basic MONO guidecam such as the ZWO ASI120MM range will be adequate. Michael

Nice work Rob ! Most people call that mod a "Ha Mod", the IR filter remains in place. If you had the bandpass and the IR filter removed, that's a "Full Spectrum Mod". Michael

IIRC there's a thread oh Cloudy Nights on sourcing and replacing the display. Michael

Hi Dave This seems to be the reverse of a graph with Dec Backlash. Usually the red dots head off away from the origin instead of following the white line. Then when the backlash has been taken up, the red line starts to run parallel to the white line. Beats me. I would post your image, and a PHD2 GuideLog and PHD2 DebugLog on the PHD2 Help Forum. Make sure the dates in the filenames match. https://openphdguiding.org/getting-help/ Michael