Laurin Dave

With the camera came a threaded ring that will screw into the 21mm extender, screw the filter into that .. it needs to be as close to the sensor as possible to minimise vignetting ..

Presumably the effect of the reducer... without it the sensor will be at the scope's native focus position, with it I'd assume it moves further in

As Skipper Billy says .. and as per ZWOs guide yes...

yes that gives the required 55mm ... See link.. https://astronomy-imaging-camera.com/tutorials/best-back-focus-length-solutions-55mm.html

yes it is .. that and the other two extenders are all you need

I assume then that you don't have the 11 mm female to female T2 extender.. which makes up the distance and reverses the threads ie the black ring on the front of the camera

Should be like this for ZWO (I think) … Flattener M48 (I assume) .. 16.5 mm T2- M48 extender... 21mm T2 extender... 11mm T2 extender (on the camera already so not shown as an accessory) then camera... giving 55mm backfocus

That's easily good enough not to cause any issues so I wouldn't worry about your PA being the cause of our woes... also just checking my PHD settings I have hysteresis at 0.3 and min mo's of 0.2...

Adam Looks like that's to do with the "failure to settle" report and some sort of re-setting .. its showing a general drift owing to Polar alignment and the PE shows as the small sinusoidal overlay on the downward drift.. Dave

Hi Adam I'd suggest longer is better as short exposures will chase the seeing.. Had a look at your settings and can't see anything obviously wrong although it is these I would suspect .. also a quick look at your logs .. the calibration steps at 1200 mm look to me as if the guide camera (or something else) may still be a bit wobbly (on the basis that my OAG at 1070mm returns calibration points on a straight line) ... and on some of the graphs the corrections on Dec are in the wrong direction.. Some suggestions for fault finding .. take SGPro out of the equation to isolate that as a cause ... guide via ST4 (ie On Camera) .. also try the guiding assistant for a couple of PE cycles (ie 10-20 mins) through the 225mm without SGPro - this should give you the PE.. and as an experiment/ test just attach a guide camera to your reflector (ie in place of the imaging camera) and see if that works... (will rule out wobbly OAG) HTH Dave

Pretty sure SGPro will tell PHD to use the profile that is set in the Equipment Profile or Control panel ( so long as the guide camera and mount are the same ).. so if it’s using 225mm focal length with the OAG the calibration movements will be so far from what it expects that it fails . Could also explain why the PE appears to be 4 times bigger (ratio of focal lengths) than it should be .. Dave

Inspired by @PhotoGav's post yesterday evening I thought I'd have a go at comet imaging .. here's the result from 2hrs of 5 and 10 min subs through my Esprit150/SX46 and 2 hrs of 1 min subs through my piggybacked Esprit100/ASI1600. Processed in Pixinsight (using the comet alignment routine) APP and Photoshop where comet RGB and Luminance were manually aligned. Subs captured between 9:30 and 24:00.. Comet position is at 24:00 thanks for looking Dave Comet C 2019 Y4.mp4

A single 10 minute lum sub on the 150... have switched to 5 min as the head looks rather elongated .. also doing RGB on the 100 at 60secs.. Dave

I’ll let you know Gav

Hi Gav.. great video and idea.. imitation being the sincerest form of flattery I’ve just started on it myself! Dave

Adam... these settings may help .. copied from Sara.. you probably have reverse guiding checked in two places.... I did at first and this sorted it Dave Sitech PHD SGPro Settings - Sara Wager (004).pptx

Thanks .. the background is a bit lumpy

From unexpectedly clear skies on Tuesday night.. Globular cluster Messier 3 in Canes Venatici was discovered on May 3, 1764, and was the first Messier object to be discovered by Charles Messier himself. Messier originally mistook the object for a nebula without stars. This mistake was corrected after the stars were resolved by William Herschel around 1784. This cluster is one of the largest and brightest. It is made up of around 500,000 stars, is 90 light years across, estimated to be 11.4 billion years old and is located at a distance of about 33,900 light-years from Earth. It is also 31,600 light years above the Galactic plane and roughly 39000 light years from the centre of the Milky Way. (Wiki) Also visible is NGC5263 a type Sc spiral galaxy about 200 million light years away and many more distant galaxies some visible through the clusters halo. Esprit150/SX46 2hours per channel RGB. Processed in APP Pixinsight and Photoshop. Thanks for looking Dave

What does the Ha you've got so far look like Dave? They're quite weak compared to the general Ha in the core and inner arms

Hi Adam... I run them off the power bricks they came with from ZWO and SX... I have plans to connect them all to the PSU via a Powerpole distribution box and tidy up/reduce the number of cables but as it works fine at the moment I've put them on hold, something to do over the summer... Dave

I have the one form FLO running my mount, focusers, dew heaters and a few other bits in my observatory... (but not the camera cooling) the only downside of variable voltage I have found is when you accidently turn it on in the dark when its set to 8v... everything seemed to work fine but I woke to find that both scopes had dewed up.. Took ages to work out what was wrong

Very nice Rod - presumably a crop?

Maybe focus or camera shake from shutter release if you don't use a remote or from the mirror rising... does it have mirror lock and do you use a remote to release the shutter? Also you want the shortest exposure you can get to freeze the seeing... Have you thought about taking a video (DSLR or smartphone) and trying the "lucky imaging" technique?

Just like mine was..... lets hope its the fix.. also pretty sure that as your guide cam doesn't bin on chip that your real numbers are twice as good as you think and that the stars are bad because of the wobbly OAG..

Interesting Goran... do you run the same guide cam exposure times on both mounts... I also sometimes get a light leak from the OAG along the stalk.. all those LEDs I expect even though most taped over