michael8554

Hi Rob I guess you're talking about a Meade 10" RCX-400 ? I think any SCT Crayford / Zero Shift type focuser should fit onto the OTA rear port. The problem is the RCX is missing the focuser socket on the control panel that most other Meade SCTs have. So you will need a handbox for it, or a focuser that has an ASCOM connection to allow control from a PC. Michael

The lower sheathed cable looks neat, and is in a nice smooth curve, but if it's stiff it could make matters worse. Rubber washers under the guidescope bracket ? Making the mount more wobbly isn't going to help ! If the bracket is tending to rotate then a metal lock-washer is required. Michael

Griffin is correct, a HFD of 1.0 pixel in the Star Profile means you were locked onto a single hot pixel instead of a star. Your location error, real or not, won't hinder you at this stage of finding if the mount is moving under PHD2. Michael

Okay, you Polar Align at around Dec = 90. What target was the mount pointing at when you tried guiding ? Did the mount Calibrate ? Calibration is where ASIAir moves the mount west a number of steps, then north a number of steps, to understand how far the mount moves for a given step size. Michael

Maybe only stack the lights that have acceptable framing ? Michael

Might work, worth a try Michael

Thanks Craig, jpegs would have done 😆 RA was tracking, this is just cumulative drift from Polar Alignment error. Were the star shapes good enough to stack ? Then carry on as usual, maybe improve the PA, or reframe as necessary during the session. Michael

The videos for replacing the battery look easy enough ? Some Torx 5 screws hold the back on. Then some Philips/Pozidrive screws for the battery. And one power connector. Michael

Neither answer is better for you. All that incorrect FL will mean is that the reported guide errors will be 10% smaller than reality. Michael

All my laptops have a catch on the underside that allows the battery to slide out of the casing. What laptop is it ? Google for a replacement battery and see if that gives you any intsructions on replacement. Michael

I've seen a wide u-shaped tray mounted between the forks onto which the small refractor rings are screwed. Michael

Have you tried running it on mains with the battery removed ? (I don't mean the button cell) That's how I run my laptops with dead batteries. Michael

I didn't mention Dec guiding at all. I suggested the mount might not have been tracking in RA. Without seeing, say, the first and last Light, it's hard to say why there was drifting. Michael

You didn't mention Calibrating ? And what Dec were you guiding at ? Michael

From what I've read here on SGL, you have to be in the correct Star Adventurer mode, or RA tracking will be OFF. Don't have that mount, so can't advise on what the setting is. Michael

I see from your GuideLog that RA, Dec and Guidespeed are not being reported from the mount, so you are ST-4 guiding ? With ST-4 you must Calibrate on every new target. Calibration took 7 steps in RA and Dec, but Dec included clearing 15 steps of Backlash before Dec Calibration started. It is well worth clearing that Backlash by pulsing north until the guidestar moves consistently, THEN Calibrate. But the guiding shows that RA and Dec are both "stiff", and so not responding to PHD2 commands - Dec took 2 minutes to correct at one point ! Both worms need adjusting. PHD2 Dec Backlash Compensation was disabled, which doesn't help. After a good Calibration, run the PHD2 Guide Assistant with Measure Backlash ticked, that will advise a starting setting for Dec Backlash Compensation. Michael

I'd say the bottom left corner is correct, the other corners are tilted. So leave bottom left alone and correct the tilt in the other corners . That may be difficult, so do your best with the tilt, then add/subtract mm's to correct any coma. Michael

Yes, in what way aren't they working ? RGB values seem okay, about 50%. Camera is well off centre. Michael

This may be what you want, from 4 minutes in :

Shows that Dec Guiding in one direction works, if correctly implemented. Michael

As in your previous NEQ problems, diagnosing without a GuideLog is just guesswork. But from your screenshot, before the DIther, Dec did not need any guiding, so PA must have been pretty good. As soon as Dec guiding was required following the Dither, PHD2 was failing to pull Dec back. Because of Stiction in Dec at a guess. Michael

Well I suppose if the vignetting at the bottom of the Flat isn't apparent on the Lights, you may be right. But I'd say its vignetting by the bottom of the shutter box, or the step between the circular lens mount and the sensor. Michael

That's not shutter shadow. 1/25s = 0.04s Michael

ASIAir produces a basic PHD2 style GuideLog that can be read by PHDLogView Michael

I've heard that too-fast exposures (0.025s, 0.001s) with mechanical shutters, as in DSLRs, may show shutter artefacts. Dim the light source until AV exposures come out at about 1 second. AV gives a 50% exposure. Michael