[jawats]

All,

I’ve had the K-1 out for 3-4 attempts at the Orion Nebula (M42) and on none of the occasions have I been able to get astrotracer runs longer than what is possible without it (at 105mm).

I always get star trails at even 1/2 or worse of the recommended time. I’ve been following the most detailed directions here exactly, without any results: Astrotracer's giving me problems, help! - PentaxForums.com

To wit:

(1) Set bulb mode. Set ISO. Focus lens (autofocus lens, used in manual mode). Set aperture.

(2) Turn on GPS. Set view screen to “electric compass” mode and wait for satellite to turn green. I confirmed that it was reading correct latitude - same as my PS Align Pro on my iPhone.

(3) Turn on astrotracer and perform alignment.

(4) Attach camera to tripod and ensure it’s aimed at M42.

(5) Press green button to ensure that astrotracer is active.

(6) Press shutter trigger.

Is there anything I am missing here? Is it possible I’m at a bad latitude? I never have issues with my phone GPS here. Thanks for any help!

—Jonathan

[jbinpg]

Astrotracer performance is at the mercy of a good calibration. Some locations with iron-rich soils will not allow a reliable calibration. That could be your problem.

[biz-engineer]

(3) Turn on astrotracer and perform alignment.(4) Attach camera to tripod and ensure it’s aimed at M42.

I'm using a mainly carbon tripod, but the ball head is made of ferous materlial, at least the central screw is made of magnetic metal.
Magnetic metal in tripod construction skews the compass when mounting the camera on the tripod after calibration the camera away from the tripod base plate.
The solution I found was to attach the camera to the tripod unfolded, calibrate the whole things, unfold the tripod ready to use, gets me perfect star dots without trails.

[Kevin B123]

Are you sure that it calibrated all three axis before the menu said OK?.
Sometimes the location may give a false OK after just two axis. That means it is not properly calibrated at that point. When this happens, repeat until all axis are attempted, then the OK comes up.

[gel56]

Greetings All.

If I'm reading "on none of the occasions have I been able to get astrotracer runs longer than what is possible without it (at 105mm)." ... you are trying to take a sharp image of M42 with a long shutter exposure (more than 30 seconds), focal length of 105mm, using the astrotracer function, and all your images so far have shown star trails.

My thoughts immediately went to looking at the moon ... by naked eye it doesn't seem to move, but when I look at it through a 900mm telescope the moon races across the field of view.

Have you had any success using astrotracer at shorter focal lengths?

[jawats]

I'm using a mainly carbon tripod, but the ball head is made of ferous materlial, at least the central screw is made of magnetic metal.
Magnetic metal in tripod construction skews the compass when mounting the camera on the tripod after calibration the camera away from the tripod base plate.
The solution I found was to attach the camera to the tripod unfolded, calibrate the whole things, unfold the tripod ready to use, gets me perfect star dots without trails.

I will definitely try that. Thank you so much!

---------- Post added 02-19-20 at 06:37 AM ----------

Are you sure that it calibrated all three axis before the menu said OK?.
Sometimes the location may give a false OK after just two axis. That means it is not properly calibrated at that point. When this happens, repeat until all axis are attempted, then the OK comes up.

It sometimes takes me 6 repetitions to get calibration. Will it definitely work after three, if I hit all correctly?

---------- Post added 02-19-20 at 07:34 AM ----------

Greetings All.

If I'm reading "on none of the occasions have I been able to get astrotracer runs longer than what is possible without it (at 105mm)." ... you are trying to take a sharp image of M42 with a long shutter exposure (more than 30 seconds), focal length of 105mm, using the astrotracer function, and all your images so far have shown star trails.

My thoughts immediately went to looking at the moon ... by naked eye it doesn't seem to move, but when I look at it through a 900mm telescope the moon races across the field of view.

Have you had any success using astrotracer at shorter focal lengths?

I have not tried it at shorter than 105, but I am using a Tamron 28-105, so I can definitely try.

[MossyRocks]

I've never turned on the electronic compass as part of my process with working with it but I don't see how that will help. I have used it to check reasonable alignment when centering Polaris in the frame. I would lean towards it not being a good calibration as it does take some experience to get good ones, or something in the environment affecting it. Also with my recently acquired K-3ii I ended up finding out that the electronic level sensor was horribly miscalibrated (off by almost 20 degrees) on one of the axes so it ended up having no idea how it was actually oriented in space so that would be something to check as well if you haven't. The place I got that camera from has a 6 month warranty on used gear so I brought it back and made it their problem. Several weeks later it arrived back after a trip to Precision Camera and is not properly calibrated.

As far as what can affect it in the environment look for large amounts of iron, so setting up near vehicles, fences, the iron range in northern MN as these will throw it off. Other things that I have found throw it off include electric motors, or anything that has a magnetic field, especially buried power lines or transformers. I've done all of those a number of times once setting up in the dark at the end of a road between 2 transformers out in the brush a little ways with a buried power line right below the tripod, once not thinking and setting up by to the air source heat pump below my deck, a number of times trying to get night shots up by Split Rock lighthouse. Forgetting that one pair of my hunting gloves has a flip open mitten portion that has magnets in it to keep the mitten part open if you want it out of the way for a bit.

Smaller amounts of iron I'm not sure how they affect it but with my setup on my big wooden tripod with made with regular steel bolts and a Manfrotto 3047 head and hex quick connect plate there doesn't seem to be a problem. I'm not sure how much iron is in the head but it wouldn't surprise me if it were significant given how heavy it is. Here is a single shot with only very mild quick edits captured with astrotracer and my 400mm wide open for 20 seconds on the setup I mentioned. The lens was still coming down to temp and that was the first quick test shot to check settings, calibration and exposure so was a planned throwaway shot and shows a lot of coma wide open which happens with that giant lens until it reaches thermal equilibrium.

Apart from all of that practice calibrating it with smooth movements along each axis and only one axis at a time. The smoother and more limited to a single axis each movement is the better calibration you end up with. I also have found it useful to go beyond the 180 degree range recommended. Often times the movements I put the camera through are closer to 270 degrees. With the K-3 + O-GPS1 there is an option to do a regular calibration and a precise calibration so I always do the regular one first followed by the precise one. Even with the K-3ii I will turn astrotracer off but have the GPS on so that I can do a regular calibration first when setting up and then switch astrotracer on to do the precise one. I would assume that the K-1 would be similar to the K-3ii in how it functions and is calibrated.

My experience is that the suggested times astrotracer provides are optimistic at best. However at 105mm a 50 or 60 second exposure should be expected to provide good results given that I will regularly do 30 seconds with a 300mm and 20s with a 400mm.

[jawats]

I've never turned on the electronic compass as part of my process with working with it but I don't see how that will help. I have used it to check reasonable alignment when centering Polaris in the frame. I would lean towards it not being a good calibration as it does take some experience to get good ones, or something in the environment affecting it. Also with my recently acquired K-3ii I ended up finding out that the electronic level sensor was horribly miscalibrated (off by almost 20 degrees) on one of the axes so it ended up having no idea how it was actually oriented in space so that would be something to check as well if you haven't. The place I got that camera from has a 6 month warranty on used gear so I brought it back and made it their problem. Several weeks later it arrived back after a trip to Precision Camera and is not properly calibrated.

Mossy,

Thank you for the detailed information!

So, I will be checking the electronic level vs a physical level and the horizon and ground. I am planning on building a wooden tripod to hold the K-1 and my Skyguider pro, so that may help. I will be checking for the presence of buried or above-ground lines, and trying in a more open area (the golf course which runs in the neighborhood may help).

--Jonathan

[gel56]

I will definitely try that. Thank you so much!

---------- Post added 02-19-20 at 06:37 AM ----------



It sometimes takes me 6 repetitions to get calibration. Will it definitely work after three, if I hit all correctly?

---------- Post added 02-19-20 at 07:34 AM ----------



I have not tried it at shorter than 105, but I am using a Tamron 28-105, so I can definitely try.

Question ... are you shooting only M42, or are you going for the entire Messier catalog? Thanks.

[jawats]

Question ... are you shooting only M42, or are you going for the entire Messier catalog? Thanks.

Messier catalog is a nice idea, but I'm currently just trying M42 because it's very visible early in the night in my sky.

When I read the first part of that, I thought, "No, I'm shooting K-mount, mostly."

[Gimbal]

All,

I’ve had the K-1 out for 3-4 attempts at the Orion Nebula (M42) and on none of the occasions have I been able to get astrotracer runs longer than what is possible without it (at 105mm).

I always get star trails at even 1/2 or worse of the recommended time.

Forget max recommended time as that will not work at all, start with 15 seconds and increase if successful. Also know that the flip-out screen, which is very useful when doing astro photo, do affect the electronic compass in certain directions. At least mine does.

It’s easily checked though by bringing up the electronic compass and move the flip out screen from tucked in to working position. If the compass moves then the astro tracer will be fooled into compensate for the wrong area of the sky.

[JensE]

It’s easily checked though by bringing up the electronic compass and move the flip out screen from tucked in to working position. If the compass moves then the astro tracer will be fooled into compensate for the wrong area of the sky.

I just noticed that my camera seems to have a significantly stronger magentic field than the earth and accordingly the compass is stuck around 190 +/- 10 degrees. With the flipped out screen alone, I'm able to turn a magnetic compass 180 degrees. The K-1 does seem to contain quite some ferromagnetic material :-(

[Aaron28]

I believe pressing the green button toggles between....the time the camera will set for exposure time and another press of the green button allows you to set the time...…

can't remember this either as I usually use a an ir remote and 3 sec delay for shots but if there is no delay when you press the shutter it could be from 'shake' even on a tripod.....maybe employ a shutter delay

[Gimbal]

I just noticed that my camera seems to have a significantly stronger magentic field than the earth and accordingly the compass is stuck around 190 +/- 10 degrees. With the flipped out screen alone, I'm able to turn a magnetic compass 180 degrees. The K-1 does seem to contain quite some ferromagnetic material :-(

Sounds extreme but maybe the camera somehow lost the calibration. I´ve seen the same behavior in other electronic compasses and that is usually fixed with a calibration.

[JensE]

Sounds extreme but maybe the camera somehow lost the calibration. I´ve seen the same behavior in other electronic compasses and that is usually fixed with a calibration.

I think it lost its ability to be calibrated with an about 10x stronger field than the earth's. I suspect that the magnetization was caused by the magnetic buckle of my photo backpack.