prusling

Many thanks for such a detailed reply. I'll throttle back the speed to 200 though I could go lower as there is a custom setting offered. Will report back!

I have Lakeside motor focusers on my 2 imaging scopes and I'm switching from using the standard Lakeside focus controller to a Pegasus eXternal Motor Controller (XMC) driven from a Powerbox. The standard controller has served me well but I'm moving to drive all my kit from the scope area and they are too bulky. The Lakeside controllers just worked and there was little in the way of settings to configure, but the XMC offers a choice of full/half/quarter/micro-stepping and max speed limits of 200 or 400. The manual recommends full/half combined with either max speed for the Lakeside stepper. During my first outing I had some issues which seem to be due to lower stepping units than the native controller which threw out SGP autofocus including its backlash compensation. The motor was also noisier than before. As it was a very rare clear night I aborted the switchover and reverted to the standard controller rather than experimenting further. Has anyone driven a Lakeside stepper motor (McLennan P542-M482U-G21L82) using other means than the standard controller, and if so what settings did you use - ideally to match with standard ones?

+1 for StarTools (latest version 7) with a GPU - I have a reasonably-priced Ryzen 4600 equipped laptop (12 cores) with a GeForce GTX 1650 (14 compute units) and it absolutely flies!

I removed mine as it was causing drag on RA. I recommend this if you can do without it.

Another factor you may need to take into account is the variation in main camera focus point when using filters, either where they are non-parfocal or you are using a refractor without good colour correction. I don't have a problem with this when using a triplet with near-parfocal Baader filters but have found that there is a significant variation in focal distance between Ha and Oiii when using a doublet, and this is enough to put my OAG focus well out. I could focus the OAG mid-way between the extremes and have it a little out of focus all of the time, but have presently reverted to using a finderguider.

TS make them and they are on offer at present! TSOAG11

I vaguely recall coming across a T-adaptor with integral OAG so it may be worth searching for that.

Yes, unfortunately it does. The amount of back focus required is dictated by the reducer/flattener - many are designed for a 55mm back focus which matches a DSLR plus T adaptor. With such there is no opportunity to include any additional length in the back focus and an OAG will require anything from 9mm upwards (mine are relatively thin at around 16mm). Some reducers are designed for greater back focus and these may be able to accommodate a thin OAG with a DSLR.

Another order placed. Thanks to johninderby for developing the mod and Adeking for pointing me to it. As well as plate-solved push-to for my Dob I plan to use it for polar alignment using Polaris for my grab and go Az-GTi in Eq mode. All that and a happy grandson with the mount and OTA! Looking forward to hearing and sharing usage experiences.

Hi, the first thing that came to mind was that you need to tell Sirilic where the Siril executable is located in File, Preferences. However it sounds as though the executable was found in your later edit. Sorry I can't help with that error message.

The custom white balance is a once-off setting on the camera which is then applied to shots taken in Auto WB mode. You may be thinking of an adjustment to the WB in post processing each time which is unnecessary.

The dual astro/daylight mod works well - you enter a custom white balance and use Av mode. Not sure that a special white balance is needed for planetary but as you don't need long exposures you can shoot in Av mode and use one. It does help not requiring an external filter although I occasionally use a UHC filter to cut light pollution. Great choices on the lenses - I have the latter (Samyang=Rokinon). At 200mm I'd recommend using vintage lenses with adaptors such as the Pentax Takumars - the quality is superb and you can pick them up at a reasonable price. You can always get a small APO as well! Here's another widefield shot, this time with the 40mm pancake.

Hi, sorry I use the Windows version. The following page (in French) https://astroslacholet.wordpress.com/2020/04/11/utilitaire-conv2siril/ advises the following which may apply to MacOS: Under linux, you must make the "sirilic.pyw" file executable or launch online command in a terminal: python3 sirilic.pywYou can associate the extension ".pyw" with the python program (/usr/bin/python) in your browser. This may be a bit of a pain to set up but I believe it is worth it as the resulting front-end is very easy to use. I have written a (Windows) tutorial which is referenced on the link above.

Hi, I've had a 550d for a number of years and been very pleased with it. It was dual astro/daylight modded byJuan Ferrios at cheapastrophotography so I've never had a problem with UV/IR bloat which can happen with a full spectrum mod without additional filtering. I have used it with a Samyang 14mm, Canon 40mm pancake and 55-250mm zoom, and vintage Pentax Takumar 135mm and 200mm lenses with adaptors. I prefer prime (non-zoom) lenses as you don't need to worry about retaining the zoom position if you take flats later. I've also used it with various scopes. As you are probably aware, the 550d unusually has a 640x480 'movie crop' mode which uses 1:1 pixels from the central part of the sensor to give a magnified image for planets, etc. My sensor developed a couple of lines across every image, which I believe is fairly common and known as "Canon banding", but I fix this by using Fitswork4 and Processing, Background Flatten, Lines to Equal Values. Here is a Milky Way shot using the 14mm lens. This was on a tracker (iOptron SkyTracker) with around 40 1-minute subs at ISO800 plus darks. You can get away without a tracker with short exposures on wide-angle lenses; there's a rule of thumb you can use. I'm sure you will enjoy your 550d - let me know if you'd like any other info or example images. Cheers, Peter

Sirilic (the simplified front-end utility for Siril) supports multi session.

Many thanks, Grant, I was also unaware you could double-click on a column header to replicate the settings! Looking forward to further SGP material from Darren.

Like you i have a 550d and I don't know whether you are aware but there is (unusually) a movie crop mode where it uses pixels from the central part of the sensor to give a 'magnified' view at 640x480 resolution. I haven't used that feature on mine for a while and I think the Moon may be too large to exploit it, but it's definitely worth considering for the planets.

Slightly off-topic - I get banding on my Canon 550d and Fitswork4 does a pretty good job of removing it using Lines to Equal Values with default parameters in the Processing, Background Flatten menu.

Many thanks Grant

Slightly OT, where did you get your Rolson Load Straps?

It requires a fairly recent processor with a specific command set that it uses. It will run on my laptop but not my older desktop.

A "SUZUKI OPEL VAUXHALL 50357 Front 246.5mm Solid Brake Disc Coated By Pagid" works well for the HEQ5. I paid around £16.50 for mine from eBay in 2016.

My experience is that accurate measurement of the resulting total backfocus is essential (e.g. with digital calipers) as sometimes spacers (for example) don't fully thread in so take up more space than expected... Many times I've worked it out on paper then measured the result only to find it's out!

I've googled "QHY183c Indi" and there do seem to be issues though some seem to have solved them with some Linux-level tinkering. This was my original plan for an economy setup to minimise cabling between the scope and mount but I ended up making the USB output to a hub on the side of the mount rather than input from it (for mount, focuser, etc) and kept the laptop connection from it to run everything rather than the Pi. Please keep me up to date on any positive outcomes as I'd like to revive this sometime. Cheers, Peter

Very nice images - love the delicate filaments on the Veil! I found 5 min subs were fine at f5 for LRGB but I tend to go longer for narrowband (my preferred mode for winter targets). The challenge for me is that you really need 16 or more subs to bring sigma clip stacking into play which I find very useful; this is one of the advantages of OSC with which I tend to use 1-2 minute subs depending on the sky background and dither. As a lazy imager the whole mono experience was made so much easier (even I would say practicable) with automated control. I don't know whether you have a motor focuser but I find mine a godsend. In SGP I can frame my intended target ahead of time and create a sequence from its coordinates, then slew / plate solve / centre, then leave the sequence running and it takes care of auto-focusing as necessary. Have you tried StarTools - I'm a big fan. It's great value and performs very well on gradients (Wipe function). Most functions work well with their default parameters but you can change them when you have worked out the effects. There's a free trial. Thanks for the networking advice - I now have the Pi running on a network cable linked to a Homeplug equivalent. It's a DIY StellarMate on a 4GB Pi 4 (you can buy just the image and source the Pi separately). I generally use a laptop with SGP and don't have connectivity issues over wifi via the extender though it is slow. I've also successfully set up the Pi in 'headless' mode with just an Indi server on the Pi, though I've also connected over VNC without any issues. The bad news is that I can't connect to either my guide camera (Altair) or the QHY getting: "Unable to establish the following devices: + QHY CCD + Altair". I had a similar problem with a previous uncooled Altair 183c with SGP so sold it and bought the QHY cooled equivalent but not got around to trying it with the Stellarmate. I'll do some digging around but it may be a problem - a pity. I'll update if I find anything out.