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A first try at astrophotography and I didn't even use a tripod.... just set the camera down on a picnic table, and held the shutter down.

Taken with the K10D and Tamron 28-75mm 2.8 @ 346.6s f/2.8 ISO400 28mm

[m8o]

That's really quite stunning! I really like your results without the star trails. I'll have to try the 50mm 1.4 next time... or maybe the 31 Limited.

At 30 seconds the star trail is still there, but it gets lost when you look @ the hi-rez shrunk down to 800px on the long side. Here's a 100% crop.



I wish I would have tried 5 or 10 seconds.

That wider FOV Limited of yours should work well too, given the sharpness they are said to have.

[Fritz]

All these shots are quite nice. I've had some fun of my own playing around with star trails. I have found that I get better results with my M 50 f1.4 then my kit lens. I've tried it stopped down to f2.0-f2.8. On the long exposures I seem to get alot of noise even with the noise reduction turned on. What are you guys doing to keep the noise level down? I also get a band of light at the top of the frame.

[m8o]

Turn off noise reduction and Shoot RAW. (at least that's what I did) I find Lightroom does a great job converting it, getting rid of "hot pixels" and other noise 1 pixel in size, while keeping the detail unaffected that spans multiple pixels. The actual unprocessed RAW image has a lot of super-bright green (and some other color) specs one pixel in size.

Regarding the band of light... Is there any light, however dim, anywhere near you when you perform the shot? There can't be. My latest one posted here that I shot at Ngorongoro crater had a red cast on one side of the frame, from light coming from two rooms down who had their light on even though the curtain was drawn. The one I did a few days earlier at Tarangire park had -complete- and utter darkness [I could barely see my hands in-front of my face when I turned-off my head-lamp] and it had no color casting what so ever. So, I'm thinking that might be behind it. BTW, to get rid of the color casting in this photo I posted in this thread, I just reduced saturation, with some WB, brightness & contrast adjustments, and ended up with what you see.

BTW, I'll add ... the star trail left from a multi-second exposure actually greatly aids the application processing the image from differentiating noise from actual star image detail. If there was no trail, it would be harder for the image processing program to tell which dot was a star and which was noise!

[Peter Zack]

I have tried this a few times as well and M80 advice on stray light is very true. Shoot at a low ISO as well. For those of us that don't use any Adobe products (yet) Ileave the noise reduction on and just make sure that I let the camera finish it's 'dark frame' to correct for hot pixels. By just waiting for it to complete the cycle I've had no issue with the final result. Maybe you're not letting it complete the dark frame/ hot pixel correction?

[Fritz]

My apologies to the original poster if I'm hijacking his thread.

Thanks for the tips. I always shoot in RAW anymore. I love the flexibility that it provides. I have been using the Photo Laboratory software that came with the camera, but I also sometimes use the GIMP. I use the noise reduction (dark frame) which takes as long as the photo itself to complete. The hot pixels are removed, but I seem to be left with noise as a result. I was thinking of playing around with a program that I found linked on this board that combines multiple frames of a shorter exposure to get the trails. Hopefully with less noise.

You are probably right on the light band that I'm getting. Probably just stray light that I didn't think would be significant. It sure seemed dark at the time!

Here is an example of what I am talking about, shot with my M 50 f1.4, either f2.0 or f2.8, ISO 200, 770.4 sec.

[hamidlmt]

No apologies needed! I'm really enjoying everyone's shots! And, the advice of more experienced folks is truly invaluable!

It really is amazing the different levels of darkness that exist... there's so much light that we're not even aware of it.

When I was shooting I left noise reduction off in the camera. There was light coming from the campground's bathroom facilities, not far from our campsite so I shielded the camera with my body. I'm looking forward to finding a really dark corner of the world to give this another try. I imagine a moonless night, in general, is helpful too.... unless you want the moon in your shot.

My apologies to the original poster if I'm hijacking his thread.

Thanks for the tips. I always shoot in RAW anymore. I love the flexibility that it provides. I have been using the Photo Laboratory software that came with the camera, but I also sometimes use the GIMP. I use the noise reduction (dark frame) which takes as long as the photo itself to complete. The hot pixels are removed, but I seem to be left with noise as a result. I was thinking of playing around with a program that I found linked on this board that combines multiple frames of a shorter exposure to get the trails. Hopefully with less noise.

You are probably right on the light band that I'm getting. Probably just stray light that I didn't think would be significant. It sure seemed dark at the time!

Here is an example of what I am talking about, shot with my M 50 f1.4, either f2.0 or f2.8, ISO 200, 770.4 sec.

[JCSullivan]

Some excellent stuff guys. To someday find or be in a place with no light pollution would be just great.

[islander]

Hello, I am thinking about getting the K10d or K100d shortly, and am interested in doing an occasional night shot.

Is there a cable trigger available for either of these models or a method of holding the shutter open without holding the button on the camera?

If its a three minute or more shoot, I don't want to start shaking the camera if my finger get tired or I start getting cold.

Not sure what the cable thingie is called, but I'm sure some one here does.

Thanks

[Peter Zack]

Yes if you check your manual the accessory is listed there. I bought this model and it works fine:

Shutter Release Cable for Pentax K10D K100D K110D *ist - (eBay.ca item 170168444798 end time 18-Nov-07 20:41:59 EST)

[Fritz]

I made my own from parts I assembled from Radio Shack. Works great, but not really any less expensive then the e-bay model. It's just that I'm impatient and wanted it that day, so I built my own!

Click me!

[m8o]

Is there a cable trigger available for either of these models or a method of holding the shutter open without holding the button on the camera?
If its a three minute or more shoot, I don't want to start shaking the camera if my finger get tired or I start getting cold.

I used the IR remote.

[Slick]

Not to keep hijacking but I was in Italy on vacation recently and decided to try some star shots on a clear night. This is one of them.



I looked a little closer and found something interesting.



That's Comet Holmes just below the center of the first image.

K10D, kit lens @ 18mm, 200 iso, 45 second exposure.

Here's a link to some information if anyone's interested in trying to capture it.

SkyandTelescope.com - Homepage Observing - Comet Holmes Beckons Skygazers Worldwide

I'm going to try again if I have clear skies any time soon. My FA50 f1.4 is broken so I'll have to try something else.

[s!lver]

wow, here in LA. the night skies doesnt look anything like the pictures posted. stupid smog.

[Mechan1k]

I should get out an take pics at night ... I always get a clear view of the milkyway ... the stars are piercing most nights.

[vizjerei]

My guess, from looking at the amount of movement of the stars, and given the location and altitude of the site of the photograph, is about 346.6 seconds.

hahaha you are funny :P