Punggai Trip Astrophotography (7 - 9 Aug 2010)

Gary · Post by **Gary** » Tue Aug 10, 2010 3:40 am

A couple of photos just to roughly illustrate how clear the sky was. Shot by the least skillful person in the group using a compact digital camera.

Looking foward to be blown away by the photos taken by orly, fizzy and cloudcover very soon!

orly_andico · Post by **orly_andico** » Tue Aug 10, 2010 8:14 am

I'm not gonna be blowing anything away.... my M31 images are mind-bogglingly full of noise. :-P

orly_andico · Post by **orly_andico** » Tue Aug 10, 2010 10:30 am

Here's M31 with the Zenithstar 70ED (420mm f/6.2), 4x 30 seconds, Pentax K20D. No flats or darks.

A few things:

1) the Z70ED is in desperate need of a flattener! notice the blob stars in the corners

2) the K20D is horrific for AP, look at all that noise! and dark-frame subtraction can't be turned off!

I got to thinking... the Z70ED is too short for the smaller DSO's, so should I just get the flattener for the Orion 100ED and use that for imaging? (the Z70 can be relegated to guiding)

orly_andico · Post by **orly_andico** » Tue Aug 10, 2010 11:27 am

I saw this jaw-dropping M31 with 55x 30s with the Pentax K-x.. the K20D is nice, weatherproof, and beefy, but completely falls down for AP.

fizzy123 · Post by **fizzy123** » Tue Aug 10, 2010 11:38 am

lol, Gary, you are thinking too much already. This is my very first attempt in astrophotography, let alone talk about using a dslr in capturing images. Anyway, many of my star photos have trails as I was over ambitious in exposure (50-60s). At first, it looks ok on the camera LCD, but when uploaded onto PC, the flaws start to show up.

orly_andico · Post by **orly_andico** » Tue Aug 10, 2010 11:44 am

@fizzy, i noticed that even at 100mm FL, anything over 10s will show trails. It's quite obvious on-screen, that's why I gave up on untracked years ago :-)

I actually have an EQ-1 mount lying around, but it has a lousy worm gear. I ordered a replacement (better) worm gear from the US and have a drive motor for it (will have to restore the old speed since am using the drive motor on my Polaris right now).

Would make an interesting tracking mount for DSLR + camera lens or a small telescope...

in other news.. I was extensively using my Pentax 100mm f/2.8 Macro lens last weekend, and.. well, it has horrible CA around bright stars. Didn't help that it was wide-open.

A big surprise for me since the 100mm Macro is considered one of Pentax's best primes.

Here's M45, the Pleiades, with the 100mm Macro lens, 3x 30s. DSS processed it in B&W (can't figure out how to force color!) so the CA disappeared. There's some nebulosity around Merope.

Notice that the stars are round all the way to the edge. Yay for flat-field camera lenses!!

Gary · Post by **Gary** » Tue Aug 10, 2010 12:04 pm

Where's cloudcover's Orion shots?

fizzy123 · Post by **fizzy123** » Tue Aug 10, 2010 12:49 pm

Selected starfield photography of the night skies of Punggai...

cloud_cover · Post by **cloud_cover** » Tue Aug 10, 2010 2:10 pm

Heh.... been busy at work lah and can't spend time at home editing pics thanks to YOG.
Prelim shots of andromeda with my standard DSLR lenses come nowhere near orly's shots though

Will post the finished shots once I get time in front of my PC at home (which might be the weekend or next week, thanks to YOG