Rallemikken

On 25/10/2022 at 12:28, SmokeyJoe said:

I bought a Zwo 120mm as a guide cam but despite months of trying every trick I could find on this and other forums, I cannot get it to focus with my Skywatcher finderscope. 

I have this combo. It's exactly 246mm from the front of the scope to the rear of the camera. Don't think you can alter the distance from the front to the lens, so if you can get this total lenght with bits and pieces you have laying around, your good to go! And, of course, any optics in the rear must out. Only tube, front lens and camera.

I run Kstars on a linux desktop in my observatory, very pleased dispite some niggles. Been many discussions on this topic. As a linux user this would be my approach if I had the rig out on the lawn within reach of a couple of extension cables:

Get a Pi3 B+ and install Linux Mint 20 or Debian Bookworm, and set it up as a headless INDI server (and nothing more) with an ethernet cable from the Pi trough the window to you laptop/desktop. Run the Kstars/Ekos suite on the laptop, and watch the subs roll indoors onto the laptop as the session progresses. Why?

* Both Mint 20 and Debian Bookworm has the complete INDI drivers in their repos. Mint uses Jasem's PPA, and Debian has it all in it's own. For older Debian, you can add Astroberry's repo.

* You can run the rig with different laptops, as long as you have the same settings and index-files (for platesolving) installed. The Pi can fail (although I have never heard of such) but it can be replaced and booted with the SD-card from the first (or from a duplicate - once installed, the SD-card is mostly static).

* With an ethernetcable the subs come in fast, and they are safe and can be inspected from the comfort of your living room. With real fast wireless you can achieve the same, but I think you need a Pi4. And my router will be the bottleneck for me.

Kstars is much more than rig control. While capturing I spend time setting up new schedules and sequences, picking up new targets, and reviewing the subs as they roll in. Sometimes I abort, do a few adjustments, and restart the capture. Much of this is done inside Kstars itself. Done in this way, you can do all these things without risking to disturb your ongoing session.

As the topic says, this is a single sub under bortle 4 skies at 60 seconds at ISO 800. Conditions average, some haze, but this post is meant to show how this CC works with this scope and a fullframe. I ordered my SL 150mm from FLO with the Baader CC, but due to delivery problems had to settle with the slightly cheaper 0.9 reducer/coma corrector from SkyWatcher. As Astrobiscuit says, the proof is in the pudding: I'm not disappointed. Slightly distorted stars at the far out corners, but this sub is shoot with a Canon 5D MkII fullframe. And to be clear: Don't stack subs with this combo without good flats. And with "good flats" I mean flats shoot against a blue sky, but with the rig safely placed within the shadows.

A good estimate of what this combo can do. Scope is right out of the box, no mods except a black stringbag around the bottom to keep my dew heater.

When the platesolving fails in Ekos, the error message gives you a few hints: Are there enaugh stars, do you have the necessary indexfiles installed, are the FOV correct and so on....   Please add the following: "Have you removed the focus mask?"  I always start the session with Vega and a focus check, then pick my target, slew the scope, and platesolve......

6 hours ago, old_eyes said:

Voyager/Viking

Looks good, but I'm a Linux user. This was the simplest for me. With a fourway relay I also have the option to open the roof before the schedule, but i havn't implemented this yet. Feels safest to do it manually, must start the computer and switch on the DSLR and mount anyway.

Short update: Opted for the boxed 4-way USB relay, installed and tested. Some remarks, all this is done on Linux Mint 20.3:

* This version does not need any power supply, but be sure your USB-port delivers enough current. With all relays closed, it pulls some amps. I've plugged it into a USB-hub with it's own supply.

* It might conflict with any other equipment connected with a USB-to-serial plug, my HEQ5 for my part; it's connected with a EQDirRJ45 cable. To fix this, we must give the box it's own shortcut in /dev. This is done by writing a udev-rule, and reboot. Just like in Windoze.

* This box and my EQDir-cable uses the same chipset. [removed word]. Yours might not, but better safe than sorry. Unplug everything, apart from the box from KMTronic, and reboot.

* Run this in the shell:
udevadm info -a -n /dev/ttyUSB0 | grep '{serial}' | head -n1
You maybe get this response:
    ATTRS{serial}=="AB0LB2GY"

* Then we write our udev-rule. Make a file named /lib/udev/rules.d/99-observatory.rules This must be done as root, or via sudo.
This is how mine turned out in the end:

Line 1: # KMTronic box for takmotor (roofmotor)
Line 2: # SUBSYSTEMS=="usb", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6001", ATTRS{serial}=="AB0LB2GY", MODE="0666", SYMLINK+="takmotor"
Line 3: # SUBSYSTEMS=="tty", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6001", ATTRS{serial}=="AB0LB2GY", MODE="0666", SYMLINK+="takmotor"
Line 4: SUBSYSTEM=="tty", ACTION=="add", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6001", ATTRS{serial}=="AB0LB2GY", MODE="0666", KERNEL=="ttyUSB*", SYMLINK="takmotor"

As you can see, I've fiddled a bit. The first three lines are commented out, line #2 and 3 are pure failures. The last line (line 4) did the trick. I suspect it was the last "S" in "SUBSYSTEMS", but we'll never know....   The  ACTION=="add" and KERNEL=="ttyUSB*" might play a role, anyway, putting them in don't seem to do any damage....

* So to the bash-file that is called after finished schedule in Ekos:

#!/bin/bash
#
#  1    FF 01 01    HEX     Turn ON relay 1
#  2    FF 02 01    HEX     Turn ON relay 2
#  3    FF 03 01    HEX     Turn ON relay 3
#  4    FF 04 01    HEX     Turn ON relay 4
#  9    FF 01 00    HEX     Turn OFF relay 1
# 10    FF 02 00    HEX     Turn OFF relay 2
# 11    FF 03 00    HEX     Turn OFF relay 3
# 12    FF 04 00    HEX     Turn OFF relay 4
#
echo -e "\xFF\x01\x01" > /dev/takmotor
echo -e "\xFF\x02\x01" > /dev/takmotor
sleep 30
echo -e "\xFF\x01\x00" > /dev/takmotor
echo -e "\xFF\x02\x00" > /dev/takmotor
sleep 3
exit

The 'sleep 30' gives the motor time to pull the roof all the way, it has a stop switch at the end of travel, timing is not cruzial for my part. The next two lines turns the relays back to their default, open configuration. I have a manual switch to OPEN the roof, and I don't want my USB-box to conflict with my manual switch in case I don't turn off my computer. The 'sleep 3' is just a precausion to let the computer finish the talk with the box. Next is 'init 0', but that's another story....

Should be easy, as long as you run Linux on both. The traditional way of editing /etc/network/interfaces doesn't always work now, miss the old days. You can check out network-manager and try to configure the laptop's LAN as a "Shared connection". I use this when I  need a screen close to my mount when PA and such. I grab a laptop, connect LAN to LAN and fire up X2go. It looks like the main computer that runs KStars (a desktop in my case)  serves the laptop the same, consistent IP.

3 hours ago, beamer3.6m said:

So what do the different 'Bin' options do when capturing frames?

To the rest of the forum, correct me if I'm wrong:

Bin 1, or "binning 1x1" isn't really binning at all. Each pixel is transfered from the sensor as is. Picture looks like the native resolution, or size.

Bin 2, or "binning 2x2" means that a grid of 2x2 (four) pixels is averaged and transfered as one. Picture suddenly gets only half as high and half as wide, and only 1/4 in size.

Bin 3, or "binning 3x3" means that he grid is 3x3, or nine pixels and so on.........

Binning is mostly used on guide cameras, to get sharper images with more distinct stars that is easier to lock on. Under certain circumstances it may be used in capture, but I don't have any experience with that.

My roof is operated by a slightly modded 220V two-way winch, and I'm planning to let Ekos pull the roof over the rig when the nights schedules are finished. I've mounted stop switches in both ends, so it's just a matter of  setting on current for a limited time, once it reach the end it switches off itself.

I've taken a look at these:    https://www.kmtronic.com/usb-relays.html

Looks like these can be operated by a single bash-script (I'm on linux). I might opt for the boxed four channel, maybe the eight. Might come handy later. Am I missing something? Anyone else tried these?

9 hours ago, Barna20 said:

Can you say something about the 60D too?

No, never used it. It's a crop sensor camera, not much different that the 600D. When it comes to DSLR's and astrophoto, the only thing three that really matters is that it's covered with drivers in software, that accesories are available, and that the sensor is of decent quality. Additinal options and functions in the menus don't really matter, you will not use them anyway. You set the ISO and expose for xx seconds, and take the raw data off the camera. It all boils down to your skills and the rest of your rig.

I have bought a used Canon 5D MkII this summer, paid 300£ for it. Looking forward to try it when it gets dark enough. I suggest you start with the cheaper 600D, and saves up for a fullframe later if you find the hobby interresting. I've done this only one season, and my log is online:  http://www.agle.no/astro/index.php

  All of theese images, with one exception (Canon 450D) was taken with a 600D. And I've just started....

Choose the 600D. They are by far the most plentyful in the 18MP+ range, and therefor the cheapest. The flip-out screen is VERY handy when you image without a computer, especially when you focus. And when you buy accesories, like coma correctors or field flatteneres, you often find ready-tuned solutions for this range of Canon cameras regarding backspacing etc. Not to mention the slip-in filters. And the 600D is very easy to astromod yourself, with the excellent guide made by Gary Honis. No welding, no pitfalls.

Big difference. Some attach the peltier element to the camera itself (with or without fan - AstroBiscuit did this on one of his hilarious videos), while others make an insulated box, with element, vents and fan (Gary Honis has a couple of really good descriptions out). What's your approach? Image mostly in cold weather, but being a tinkerer, this is tempting!

I'd say you start with a scope for visual. An 8" f/6 dobsonian. Sweet spot in price, aperture and focal lenght. They are cheap and easy to sell if you want to upgrade later. If you first buy a setup for astrophotography, you will miss a scope for visual while imaging. Even if your AP-scope is big enough to really be useful for visual, the hazzle of removing the photogear each time you want to take a peek will put you off. And those tracking mounts with GoTo are not that useful for visual. I bought my AP-rig last spring, and imaged the whole season without putting on an eyepiece. This winter I also have a dob in the shed.

Have you tried the generic indi-qhy under Kstars/Ekos? They claim to cover everything from 2015 and onwards. Be aware, theese drivers are constanly updated.

I also shoot with a modded 600D, and stack both in DSS and Siril. Never had issues like you, must be a weird setting.

First: DSS (and Sequator as well) present the finished stacked image in an other way than Siril. Flat and colorless, as Siril seldom shows more than a black square. Load the Autosave.tif/fits into Siril, and play with the preview options (Autostretch and Histogram stretch). There may be more in it than what is immidiate visible.

Second: When shooting with a modded camera, you will need the color calibration routines in Siril, at least it willl save you some work. I always start a stretch with the photometric color calibration in Siril. Than I do a couple of very carefully Asinh-stretches, before I finish in Gimp.

Some times DSS does the best stack, other times it's Siril. I even have had targets that stacks best in Sequator. It's all about learning how to set the options, and as Siril gives you best control, I slowly improves my skills in Siril, and it's the stacking software I use most nowadays. Not the easiest to learn, but not impossible either.

Take a look at this:

https://stargazerslounge.com/topic/385345-skywatcher-150-pds-issues/#comment-4205909

Works for me.

I think DSS saves the stacked image in the "Lights"-folder, with the name "Autosave.fits" or similar. Look for it there. Btw, I don't do any image processing or converting in DSS itself. I take the fits-files into Siril, does a couple of tweaks, and export them as tiff's, which I finish in Gimp. If you dont have Siril installed, DSS can be configured to save the finshed image as a tiff, which you can work on in Gimp or Photoshop.

Nice, lucky you. I live at 65°N. This year Pluto will not rise above 3°. It will not rise high enough to image from my obsy for 100 years or so.  So no Pluto for me.

On 10/05/2022 at 19:06, Parziva1 said:

I know Dobsonians usually aren't that great for astrophotography

True.  But as suggested earlier here, you can put the tube on an equatorial mount later. If so, bigger is NOT better. The weight of the tube of an 8" or 10" will need a massive mount. I'd go for the SW 150 Classic dob, the same focal lenght as most 8 and 10", and the tube alone is light enough to ride on a HEQ5 when you have consolidated your savings. Actually, it looks a lot like the 150 PL OTA, a scope that is very good at planetary and narrow deep-sky AP with some mods.

In AP, the mount sets the boundaries. Both on tracking, payload and durability. Anyway, I'd be hesitant to spend much money on a integrated solution like the Celestron.

15 minutes ago, Archiewbrown said:

I have read somewhere that I need a 4mm eyepiece, is this correct?

No. First you must sort why you can't see what you want with the eyepieces you already have.  Some things to check:

-- Collimation. Does the moon look crisp and sharp? If so, continue.

-- Focus. After you have taken a glimse at a crisp moon, have you fiddled with the focus knob? If so, don't. Some adjustment may be necessary when you switch target, but not much, and not untill you have the new target in sight. If you switch eye-piece, focus will have to be adjusted.

-- GoTo-function. This scope is computerized. Don't know exact how it aligns itself, but the chances are good that you are staring into the abyss while the mount tells you that Saturn is dead-center. At least align the finderscope 100%.

-- Expectations. You should be able to see the rings on Saturn with this scope, but not every night. If it is low on the horizon or the seeing is bad, Saturn will just look like any other star. Trust me, I have an 8" f/6 dobsonian, and clearly defined rings around Saturn is regarded as a bonus for the evening. Truth be told, I live at 65N, so it's alvays low. Also remember that imaging and visual is two completely different beasts. When you see an image of Saturn, with the rings and the Cassini division, the only thing you can expect to see through an eyepiece in the same scope is a slightly oblong star....

Clear skies, hope you find your Saturn!

1 hour ago, pipnina said:

Outside it's a laptop with ubuntu, indi server in a terminal and the PHD2 app
Inside it's an Arch Linux desktop with Kstars

Anyway, under linux PHD2 uses INDI (as far as I know), so it should be possible to run it from inside. Btw, I have settled on the internal guiding in Ekos, took some time to master it, but now it works at least as good as PHD2. Kstars is a child of KDE, which in turn is King_Of_Options. Ekos started to guide well on it's own once I learned to configure the camera. PHD2 took care of this itself, but in Ekos you must sort out all the options in the INDI Control Panel on your own, without much hand-holding.

Cheers!

5 minutes ago, pipnina said:

I may go the VNC route as you suggest since it would be good to be able to adjust PHD without going outside as well.

Not sure if I understand your setup. What OS is on your inside desktop?  You run Linux/Kstars/Ekos (with PHD2 for guiding) inside, and a laptop with Ubuntu at your rig that runs the INDI-servers (and only those) in a terminal window?  Or do you run Windows/Kstars inside, and Kstars/Ekos/PHD2 on the Ubuntu laptop outside? The fact that you must out to correct PHD2 points to the latter. You must run PHD2 on your laptop outside, and it gets it's input from the INDI-servers on the same machine.  Anyway, the Ekos-window you open when you start your session treats the file paths in accordance to where it self sits. And the fact that the images travels indoors suggest you have some kind of network. Sounds like a complicated setup. And why the videos are reluctent to come indoors, I don't know.

Guess your rig is controlled by a Pi, or something, if so, it runs linux. Most likely the whole Kstars application runs on this thing, and you use some VNC to monitor it from inside on a windoze machine. Run like this, your Pi is a server for it's own client. You only monitors and control it from inside.

First, I will advice you to try running only the server on a headless Pi on the rig, and a laptop with linux/Kstars/Ekos inside, and use the Pi as a server and your laptop as a client. If you like things as they are, and just want the images to travel directly indoors, you have to use some network file sharing. The place where linux and Microsoft meets to do this is Samba. Samba is included in almost all linux distro's as default, most likely in your Pi too, if not it can be installed by a couple of lines in the shell. Can't help you setting this up, havn't used windoze since y2k. In this way you can VNC into your Pi as usually and set the filepath for your images to a samba-share on your indoor-laptop. Will demand some heavy bandwitdh, though...

If you already use linux on your indoor laptop, then NFS is the thing to reach for. Very simple to set up, and on this issue I might be of some help!

12 minutes ago, thestargaze said:

When do I know when it will be less distortion due to horizon? 

Stellarium is your best friend. Turn on the azimuthnet on the bottom toolbar, and click on the clock on the left. Wander through time. I was out with my 8" dob myself last night, trying to catch Jupiter. I live at 65N, so it was only 20  above horizon, rarely gets any higher. To bad, Jupiter and the Orion nebula - two of the best targets for visual and AP, so hard to reach at my location. No pictures, but I could just see the banding on Jupiter if I used a little imagination. Saturn never climbed over my horizon.

I have both 450D and 600D's. In my experience, the best tool you have while taking subs is the histogram. I set the ISO and expo-time such as the histogram peak is on the left side, thats 1/4 to 1/3 from left. I never let it go beyond 1/3, if the sky lightens over time I abort and reduce exposure. If it is a really dark night I start the session with the histogram peak 1/3 from the left. It's not only about gathering light, it also counts what light gets registred.

I'm blessed with cold weather and bortle 3/4 skies, and usually use ISO 400 and 800. If I can set the ISO to 800 and exposure to 240 sec, and still have the peak at 1/4 from the left, I'd say thats a good session! Usually I expose 1-2 minutes @ ISO 400 or 800.