Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

A beginning imager's successes and bloopers


MikeP

Recommended Posts

I thought I'd share last night's experiences. Probably a bit of a laugh to some of you but possibly helpful to others. Sorry it goes on a bit.

Last night looked promising so at about 5pm, I set up the ED80 on the EQ6 and roughly polar aligned with a compass, ready for later drift aligning (house obscures Polaris). Dumped camera, laptop, cables etc. outside to let it all cool down and went back in to cook tea (Mrs MikeP's night off).

Looked out from time to time until clouds disappeared (around 8.30pm) and was pleased to see that the dew heater was doing its job. Popped in the illuminated reticule, switched on the mount and slewed to a bright star in the south. Now, I have to admit that this was only my second attempt to drift align, but I was full of (misplaced) confidence. I observed the star's drift, made one adjustment to the mount and watched again. It didn't seem to want to drift any more, so I thought "cracked it" - lets adjust the altitude. Slewed to a bright star in the east and watched for drift - "ah ah", I thought "this setting should be OK because the mount is in the same place as last time and I haven't touched the altitude adjusters". So after a cursory period I decided the mount was aligned. As you may guess, it was close, but undeserving of a cigar.

Did a two-star align using Vega and Deneb. Was pleased to find that the mount slewed fairly closely to both. Must be well aligned I thought.

At this point I removed the eyepiece and diagonal and inserted the Atik, powered it up and connected the USB lead to the laptop. I fired up Maxim and connected to the camera - well, tried to. It didn't want to know. This seemed strange because I was sure I'd done a test connection indoors some time ago and it had worked. Rather than mess around in the cold, I took the camera indoors and tried to connect to Maxim on my desktop. XP didn't want to know, so I installed the drivers and plug in and voila it connected. Back outside with the camera and CD and plugged everything in again - strange no complaints - so I tried to connect to Maxim again and did so with no problem. The lesson here (I think) is to check your cables are firmly plugged in.

I'd decided to start with M31 because it must be easy, so I used the GOTO and slewed to M31. "Hmm, I wonder if it's pointing at M31 - I can do a short image and see if anything appears. Oh damn, should have focussed on a bright star first, no matter, M31 is bright I'll focus on that". I then spent an amusing 30 minutes or so trying to make something other than a big smudge appear on the laptop. Eventually I decided perhaps that is what I should see, took a series of exposures and stacked them. The result was a much more detailed smudge. After a bit of head scratching, I remembered I'd removed the diagonal and hence I should have added the extension tube - no wonder I couldn't get a focus. Two lessons here - don't be an idiot and focus on a star before you try to find a DSO.

After that, it was fairly easy to focus and centre M31. I took a series of 50 images of 5 seconds each and watched them download onto the laptop. After a little while I noticed that M31 was "rotating" and so were the stars in the image. Oh no, the Atik was being pressed against one of the tripod legs (M31 was very high overhead) - another lesson learned. Stop the sequence, move the camera and start again. Got my sequence of 50 subs.

Unfortunately, (only played with them this morning) the core in each sub was very bright, so stacking has just given me an even brighter core. I've concluded a much shorter exposure was called for, so next time I'll experiment a bit with exposure / stacking.

It was then a toss up between M33 and M74. For no good reason I chose M33. The GOTO slightly missed M33 (I wonder why) so it took a few minutes of taking shortish exposures and moving the scope with the hand control, but I found it and centred it. It seemed pretty dim, so I decided I'd do 50 subs again, but this time 30 seconds each. The process was uneventful and I got my 50 subs, but it was at this stage that I realised the drift alignment had been sloppy.

In the first sub, M33 was in the middle. By the time the 50th sub appeared, it had moved getting on for half way to the top edge. Also, the 30 second exposure had resulted in some star trailing. Bit disappointing, but the images looked OK for a first attempt.

It was at this point that a monkey passed by with welding equipment and I realised it was freezing cold and 1.45am - late enough for me, so with a last look at the sky (particularly Orion appearing above my neighbour's house) I packed up.

This morning I stacked the M33 subs with Maxim - what a clever piece of software - it coped with the quite significant drift that had occurred. I've attached a (very) slightly stretched version, which I'm quite pleased with for a first attempt. Next time, I'll pay a lot more attention to the drift alignment (I've ordered a barlow from FLO so I should see the drift a bit quicker) and hopefully not make some of the silly mistakes again.

Mike

1857_normal.jpeg

(click to enlarge)

Link to comment
Share on other sites

:D:lol: :lol:well that was a cracking read Mike , loved it and it reminds me of me lol every night , i even forgot to take my lens cap off and wondered why i could not find a guide star,

But getting back to your image , well done , its a darn good image , and what a way to start. i have been a long time doing unguided imaging Mike ,and got some pleasing results , so no problems for you , just keep that going like last night and we can expect some more very good images from you .

well done

Rog

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.