[Grimmus]

not quite the case, the K-3iii does it as well

Thanks @kypfer! Well gobsmacked I'll remain......didn't think about the NKOTB (K3-3). This thread might have started when the K3-3 was just a twinkle in someone's eye. I like my Kp for nightscapes even more now!

[scotty1]

I can't get my K70 to use Astrotracer in Bulb or manual mode. I do the calibration and make sure the GPS is on etc. I may try getting out of town to see if it's a GPS problem.

The only way I can get any success is with the user3 mode Astrophoto. I can get 20 seconds without startrailing with the 55-300 HD WR lens at 300mm.
I turned off noise reduction in this mode as I wanted the RAW files unedited.
I may try turning the inbuilt noise reduction on again, to see how the jpgs turn out for stacking.

With my K5 I can use the Astrotracer in Bulb mode, and use a remote to open/close the shutter as needed. It seems more straight forward with the K5.

[kypfer]

I can't get my K70 to use Astrotracer in Bulb or manual mode. I do the calibration and make sure the GPS is on etc. I may try getting out of town to see if it's a GPS problem.
The only way I can get any success is with the user3 mode Astrophoto. I can get 20 seconds without startrailing with the 55-300 HD WR lens at 300mm.
I turned off noise reduction in this mode as I wanted the RAW files unedited.
I may try turning the inbuilt noise reduction on again, to see how the jpgs turn out for stacking.
With my K5 I can use the Astrotracer in Bulb mode, and use a remote to open/close the shutter as needed. It seems more straight forward with the K5.

Not quite sure what the question is … in Bulb Mode, the infamous Green Button switches from manual control to timed release, 10sec to 20min … not sure why one would need to use Manual for Astro' work.
Have you activated Astrotracer in the menu or on the control panel? … the User3 'Astrophoto' seems to do that by default.
I usually take the Astrophoto settings as a perfectly good starting point and set the exposure time to suit the combination of focal length, background pollution, working aperture and ISO.
The camera will limit the exposure time available depending on the focal length, but this setting seems to be only a compromise, as shutter speeds need to be shorter with the camera pointing near the celestial equator than they do to the celestial pole.
Depending on the number of exposures required, in-camera noise reduction can be very adequate, until such time as it starts to be a nuisance 'cos it takes longer than you'd like At this point you can switch noise reduction off to save time making actual exposures, but you'll need to spend time at some point making 'darks' and 'flats' etc. later to compensate … very much an individual choice
I've only tried cameras other than my K-70 very briefly with the GPS module … the K-70 just seems to be so much easier to use, with it's fully articulated screen.
If I remember correctly, the K-5 has a reduced set of features, compared to the K-70, so that might be why it seems "easier" to use.

[scotty1]

Hi thanks for replying

Yes I tried all the menu settings, and calibrating the GPS then the Astrotracer . I was able to get good shots in the Astrophoto mode, so I will stick with that unless I can work out the other modes. Sometimes the Astrotracer just doesn't play ball maybe it's the signal, or interference from metallic objects.

[kypfer]

Sometimes the Astrotracer just doesn't play ball maybe it's the signal, or interference from metallic objects.

Absolutely … because of my domestic location I almost invariably drive out a few miles to get clear of at least some of the light pollution and more than just a fixed field of view. By trial and error I've found that if the camera is within about 10ft of the car when I try to calibrate or use it, the results are likely to be poor.
By using an ordinary old-fashioned hand-held compass in relation to the North Star I was able to ascertain my little Renault was distorting the local magnetic field quite extensively, and that was with everything switched off … I'd imagine a larger vehicle could be even worse!

[MossyRocks]

By using an ordinary old-fashioned hand-held compass in relation to the North Star I was able to ascertain my little Renault was distorting the local magnetic field quite extensively, and that was with everything switched off … I'd imagine a larger vehicle could be even worse!

Likely. Where I shoot there is a spot where I seem to get the best results and have my car parked on the other sideof the lot and there are a fe sign posts, a picnic table and big park provided barbecue that I need to stay away from. Iron is everywhere and it will throw it off but it can be avoided or minimized.

[scotty1]

Yeah when I used my K70 the other day , I drove a few miles from town to get darker skies. I made sure I was a good twenty feet from the car when I calibrated the Astrotracer. I expect telephone cables or underground cables may effect the GPS too.

We had a fair area of undeveloped land by my area. Unfortunately there is ALOT of new buildings going up, this will create alot more light pollution nearby.

I guess it's the same world over, it's getting harder to find dark skies nearby.

[scotty1]

Tried something I hadn't before tonight,
I calibrated the Astrotracer with my camera on the tripod. It was a bit awkward, but I felt less likely to drop the tripod, rather than calibrating the camera by itself. Firstly I calibrated the GPS in the wrench menu, then calibrated the astrotracer in the astrotracer menu. I was then able to use the bulb mode, instead of the user mode 3 astrophoto. I did this in the back garden. Next time I'm out of town trying astro, I will use the calibrate on the tripod method.

[MossyRocks]

Next time I'm out of town trying astro, I will use the calibrate on the tripod method.

I've wanted to do that but the heads I have that I do astro with don't have 180 degrees of travel on at least 1 axis so I haven't done that. I have thought about creating a PVC construction that allows movement in all 3 axes . Some 1" PVC pipe and a bunch of elbows and T fittings and it should be doable at a fairly low cost.

[slartibartfast01]

I've wanted to do that but the heads I have that I do astro with don't have 180 degrees of travel on at least 1 axis so I haven't done that. I have thought about creating a PVC construction that allows movement in all 3 axes . Some 1" PVC pipe and a bunch of elbows and T fittings and it should be doable at a fairly low cost.

I thought he meant physically lifting the tripod and rotating it in all 3 planes. I did try that once before deciding it was too difficult even with the legs retracted.

[MossyRocks]

I thought he meant physically lifting the tripod and rotating it in all 3 planes.

I don't think I could do that with any of my tripods I use for astro and I am a pretty strong guy and I wouldn't want to risk my big astroglass as that only makes things worse. The small astro tripod I use is an old manfrotto 3058 with the 3057 head and the other astro tripod is a home built monster that makes the 3058 look like a little unstable flimsy toy.

[scotty1]

I thought he meant physically lifting the tripod and rotating it in all 3 planes. I did try that once before deciding it was too difficult even with the legs retracted.

Yes this is what I tried, I have a velbon D7000 tripod. The tripod is quite old and the pan arm fell off a while ago. It's a fairly sturdy tripod for astro, as I'm only using a DSLR and lens. I attached my K70 to the tripod, with the legs retracted, then did the calibration and it functioned ok. I did this in my garden.

Yesterday I was out around 4 miles from town in a rural area. I tried to calibrate my camera in the various menus, and by rotating around the axis. I was in the middle of a field well away from power lines buildings etc.
It said calibration was completed but it wouldn't track stars, and only allowed 10 second exposures in Astrophoto mode and Astrotracer mode. After about 12 attempts I gave up, and put the camera into manual mode. Thinking back I was calibrating the camera while it was not on the tripod.

When I returned home I put the camera on my tripod, walked out to the garden and tried the calibration again and it worked. I was able to get 10 seconds zoomed to 260mm without obvious trailing. And one at 20 seconds with slight trails.

So when it calibrates and works it's pretty good, but as mentioned by other people it is a bit hit and miss. One thing I've found is having the camera on the tripod, makes calibration a bit smoother
and maybe safer.

[MossyRocks]

I expect telephone cables or underground cables may effect the GPS too.

Yes it will. I know people have had issues using astrotracer under or near high voltage lines and I had a terrible time the last time I was out in Colorado and inadvertently setup right on top of some buried power lines. Didn't figure that out until after dawn when I saw that I was right in line with 2 transformer/distribution boxes. Also soil with a lot of iron in it will throw it off so it becomes basically unusable, another thing I learned the hard way when trying to use it up in the Iron Range of MN.