[Learjet]

Yeah it was pretty bad a few hours ago. Even the windows fogged up!

[weathermon]

I continued the Helix nebula tonight and now have a total of 2.5 hours worth of images. Heaps more detail on the core especially! I also finished building a dew heater from resistors so have that running There's an Excel Spreadsheet from Alan Sheehan B.E that I've converted to PHP and put it on my site here - http://www.facebook.com/l.php?u=http%3A%2F%2Fastrophotography.bsch.com.au%2F&h=tAQH4MsvW

[ruggiex]

I had another go at capturing stars using O-GPS this past weekend. Although there were still a lot of light pollution where I shot this, the result after some PP is better than the first time around. Still got a lot to learn!

[weathermon]

Nice shot mate! Glad you're having success with the O-GPS1. They're not the easiest units to use (precise calibration) and they really smash the AAA batteries fast. Well the 2 dew heaters I made are working a treat! almost 90% humidity and not a drop of dew on the lens ) Been imaging now for close to 4 hours (M8, M20 and now M31)

[weathermon]

Lagoon and Trifid Nebulae - 10x5 minutes @ ISO400 on both images. Far out what an improvement since when I first started with M20!

[VoiceOfReason]

Has anyone tried ISO 80 with the K5 for this? If so is it worth it?

[interested_observer]

Has anyone tried ISO 80 with the K5 for this? If so is it worth it?

Well, this last weekend I was out shooting (using my K5) - with the intent of trying to get the Milky Way with the O-GPS1. But I also wanted to get the landscape element with out the astrotracking (static element smearing) - I had the camera at ISO 80 for the first frame which came out black with a 30 second exposure. So, I had to dial it up to about ISO800 to start to get any definition in the landscape (using 30 second exposures). So using ISO 100 as a target...

ISO .... exposure
800 .... 30 seconds
400 .... 60
200 .... 120
100 .... 240

So, you would probably need to go about 300 seconds (~5 minutes) or so at ISO 80 to get a reasonable image given a moonless dark night. So, the answer is yes - you just need to relax and slow your shutter speed. I wanted to take about 5 frames to stack and average the noise out even more.
______________________________________

I went over to my other system and was pursing a number of shots that I have taken of this one location at night (MW) with a landscape element. ISO 1600 is pretty clean, but not really enough to print at 20" x 30". On several occasions now, shooting from slightly different locations, and using about 8 to 10 frames, I have what I need (I think). I want to stack, and I tried it with my tone mapping utility, it did a great job, but on closer inspection - still noise. I am going to have to use some stacking that will average out the noise. Either that or I could go shoot a number of 5 minute shots at ISO 80.

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Last edited by interested_observer; 08-28-2014 at 08:56 PM.

[weathermon]

Tonights setting moon here in Mackay Australia

[Learjet]

Super shots Mike! Looks like you are having a ball in this clear weather.

[Learjet]

Comet C/2013 A1 (Siding Spring) passes cluster 47 Tucanae. ED100 at F7.2, Pentax K-5.

[pixelsaurus]

Comet C/2013 A1 (Siding Spring) passes cluster 47 Tucanae. ED100 at F7.2, Pentax K-5.

Very cool. What is the blobby below the comet? Cheers.

[Learjet]

It's a little globular cataloged as PGC260239.

[smigol]

NGC 6960 as seen with my camera and scope over this summer. Several nights and several sessions went into the data gathering. Lots of issues with the setup stemming from centering, collimation, sensor squareness to the light axis, and flattener spacing all gave a lot of bad data with very little to show.

In the end, this is the result of 24 subexposures of 1200 seconds for 8 hours of integration. Stellarvue SV4 scope with SSF6 flattener and IDAS HEUIB-II filter. Pentax K10D camera modified and cooled. This is the same camera that I've been using, it continues to have the permanently broken shutter and now sealed reflex mirror. I've also permanently fixed the shake reduction to avoid smeared stars.

[jbinpg]

Stunning, Stephen. The red DSOs are the hardest to image. The human eye and unfiltered DSLRs are poor at picking up the red objects. I have often wished I could just look up and see the Heart and Soul nebulae beaming but it just doesn't register. Maybe one day there will be Ha filtered binoculars with image pumping to increase the signal.

Jack

[smigol]

Thanks! It's hard to see in the version here - there are wisps of red nebulosity "below" 52 Cygni. I didn't expect to see them and it was surprised that they showed up. Having darker skies and decent flats really makes a difference. The IDAS HEUIB-II filter is a broadband UV/IR filter with a notch just above 650 nm to reduce the red sky glow without losing definition of Ha. This loses SII sensitivity, though.