MikeeJC

Thanks Martin I suppose the only way is to send the curve to the mount and see what happens... or run another session (if I get a long enough stretch of clear sky) and then send it to the mount straight after.

Thanks Ivor I've watched Astrobloke's video and a couple of others but although they say the PEC can be written to the mount during the day, there's no mention of what happens if the mount has been moved and put away i.e. clutches released etc.

Thanks. Haven't tried PHD2's predictive PEC algorithm as yet, maybe worth a try.

I've always used EQMOD's AutoPec when guiding but now wanting to use PPEC instead (although not sure if it's a major advantage or not). I've created a PEC curve over 9 cycles and know to go into the developer area of EQMOD and record this to the mount. My question is, I've heard this can be done during the day but how does the mount know when to sync with the curve? Does the mount have to be in exactly the same position as when recording the curve? As I have to set up each night I've already taken the scope off and moved the tripod into the shed. Is it now too late to load the curve and send it to the mount or can I just make sure it's in the home position before sending it? Thanks Mike

Does it matter where the scope is pointing when recording a PEC curve using EQMOD? I can't get my head around why it would make any difference as the periodic error in the worm drive would be the same wherever it's pointing..... or am I wrong? My mount is the EQ6R-Pro. Thanks, Mike.

Apologies if this is in the wrong group. Is there a comparison review between the Antlia ALP-T 5nm and the newer Altair 4nm dual narrowband filters anywhere? I've been looking but as yet no luck. I had set my mind on getting the Antlia ALP-T but now Altair has brought one out it's made me think I should hold off until I see a comparison between both. Thanks, Mike

Another M51 Whirlpool galaxy here. Taken over 3 nights in April (after waiting ages for a clear night, managed to get get 3 over the month). Total of 11 hours, 46 minutes integration time. Plus 50 dark frames, 40 flats and 20 dark flats. Taken with a RisingCam IMX571 OSC, Esprit 120ED on a EQ6R-Pro mount. Stacked in DeepSkyStacker, processed in Siril, Adobe Lightroom and GIMP.

Not that I'm aware of although I left it running and came in before this occurred. The way the light bars radiate out in increasing radius looks like some sort of shockwave effect. Think I deserve an APOD for this one 😂

That is a good point. Looking at Stellarium, back to the exact time it happened (and taking into account the image is reversed) the 'flash' appears to have come from the South West direction. My target was North North East relative to my position. It looks more likely it's either come from my shed next to the left of the scope or maybe neighbour's garden. Still very strange though, never seen a pattern like it.

I have just got around to checking my individual subs from the 14th February where I left the scope out overnight getting data on the Cat's Eye Nebula. On one of the 3 minute subs there is this very odd 'firey' pattern which has appeared but all the others, before and after, are exactly fine and how they should be. Has anyone ever seen anything like this? I've absolutely no idea what it could be. Almost looks like an explosion with the shockwaves coming out from it. The more bluey image is exactly how it looks from the FITs sub and the more orangery one has been run through DSS by itself without any calibration frames. Clear skies!

Another M45 Pleiades aka Seven Sisters star cluster here in the constellation of Taurus. Taken over 3 nights. Total integration of 10 hours, 51 minutes. 15 x 240secs & 197 x 180secs. Equipment: Sky Watcher Esprit 120ED APO refractor, Sky Watcher EQ6-Pro mount, ZWO ASI120mm mini guide camera & 30mm guide scope. Capture Software: NINA, PHD2 & Stellarium Processing Software: DeepSkyStacker, Siril, GIMP, Adobe Lightroom. Clear skies! Mike

Hi Onikkinen. Thanks for the info. Yes, I always use HCG mode. I haven't tried LCG despite the sensor analysis stating you get a much higher full well depth in LCG at the expense of much higher read noise. My dark frames have been taken indoors completely covered as you mention and all look good (apart from min=0 also) but the dark flats are taken outside as they are straight after the flats, which I take just before a session as this is more convenient than after as I usually leave it running overnight while I'm in bed. As you mention, it is always the first dark flat frame taken directly after the flats which has these elevated values. I'm a little dubious of the figures ASIFitsView histogram is giving compared to the visual histogram, although that could be me just not understanding them correctly. I've attached a couple of screenshots of a light and flat frame showing FitsView histogram.

Hi. I run the gain at 100 with an offset of 20 which seems to be popular for the IMX571 sensor and the images come out pretty good. I will have a play at changing them a bit and see how the average and minimum values change. Thanks. Hi Gary. I'm using the native driver as from what I can remember (it's been a while) it had better functionality and control compared to the ASCOM driver. That said, I'll try changing to the ASCOM driver and see if I get the same result. Thanks.

I'm experiencing a strange issue when starting to take dark flats in NINA's flat wizard. Having looked back I realise it's always happened but only just noticed after switching to ASIFitsView to check the images prior to stacking. The first dark flat taken always has a green bayer matrix visible when stretched which the other frames don't. Also the histgram is showing elevated figures suggesting there's some light present. Although the scope is covered with its lens cap and a folded dust sheet, also taken at night so there's no light entering the OTA. If there were light leaking in then all the darks would be the same. I'm using a RisingCam IMX571 OSC camera which appears to working well. I know I can just delete this single 'incorrect' dark flat frame but it would be nice to figure out why this is happening. Any ideas greatly appreciated. Not sure if it's a NINA or camera issue. I've attached an image of the first flat dark and also the subsequent one to illustrate. Clear skies! Mike