Yesterday evening I took another shot at capturing the milky way. The result is this



It looks ok (I know there is vignetting, it's not processed in any way). However, when I zoom, the stars show motion. I exposed for one minute using the astrotracer on the K-1,and I took the same image with astrotracer turned off, using bulb. They look the same. Here are two in camera crops






What am I doing wrong?

Thanks.

Can't see the images ?

Little boxes with x's in them.


That is your problem.

Should be fixed

Much better now Bernard, thanks.


Although I don't have experience using astrotracer, there have been many similar posts here regarding the same issue. From the results of those posts here are some questions:


Did you calibrate the camera for the lens used?


What direction was the camera pointed? How did you align it with North?


Have you tried a shorter exposure time? I read the exit and your exposures were about 60 seconds, perhaps 30 to 40 seconds would produce better results.


The crop you shared here is from the side and lower corner of the image. How do the stars look more towards the center? From what I have read, wider lenses (you used a 16mm) will show more trails around the edges.

right, compare the stars in the center...

also you can do a calibration more than once on a given night... sometimes it seems it doesn't catch it the 1st time...

I did calibrate once. I was looking due south.

I read that wider lenses are not ideal. What bothers me, however, is that both crops look the same, whether astrotracer is active or not. Especially the foreground. Whatever else happens, the trees should be blurred if astrotracer moves the sendor, shouldn't it?

I had used a longer exposure time (4:20 min) and reduced it to one minute when I saw traces.

How did you set that up? Compass?

That is what I have read too.

Yes, the astrotracer works by moving the sensor, very slowly, to account for the rotation of the Earth.

If the foreground is not blurred then I would suspect the function of the astrotracer either was not set up and active during the shot, or it has malfunctioned somehow.

But how much foreground blur should be dependent on the focal length and how long the exposure is.

I made some night shots with my K5IIs and a Sigma 28mm manual lens last year in Death Valley, and was able to get great shots without an astrotracer. I set the camera up to expose for about 30 seconds, and was able to get pictures without star movement.

Racer X, my experience without astrotracer matches yours. But if the stars are blurred, the trees should be too. Maybe as Weevil suggests I should have done the calibration twice.

Ok so I tried again tonight. K-1, DA40 limited. Attached the camera to the tripod THEN performed two calibrations, set the tripod down, used one minute exposure time, looking south.

Same results, I can't tell apart the images with and without the astrotracer active.

Either it's not working properly or I'm doing something wrong.

Do you have an APSC camera that you can try the OGPS1 on?

I have been reading along - even though I don't have a K1 - but I did download the manual. The GPS user interface is much nicer than with my K5IIs &GPS. Anyway, here are some stupid questions.

• What color was the satellite icon on the rear display?
• Have you used PhotoME (free download) to see the EXIF meta data which contains the GPS coordinates (lat, long, altitude) and whatever other information it has associated with the GPS.
• Did you have the camera in [B]ulb mode?
• When you go into the compass display after calibration, does the bearing track where the camera is pointing? Also, it should have the location data which should change when you are walking around with the camera.

I don't know that doing the calibration with the body attached to the tripod would help matters any.... After reading the thread a couple of times, I am thinking of Murphy's law - what ever can go wrong - will...

Doesn't look like the astrotracer is on at all. Even a poor calibration should result is sensor movement that will be obvious on terrestrial objects.

Check the simple things - astrotracer is enabled in the menu, you have switched to Bulb (B) mode (when you do the rear LCD should proudly display 'Astrotracer', it renames the bulb mode), that your GPS is on (I assume the K-1 has the orange light on the prism hump, when lit GPS is on, if not, press the GPS button) and that the GPS has locked onto the satellite signal (look for the green satellite icon on the rear LCD).

I suspect one of these is the problem, probably your shooting mode or the GPS not being on.

Indeed it doesn't. I had programmed my settings in a user mode, maybe that's the problem.

GPS was on, satellite icon was green, exif does contain the exact coordinates, but I can't confirm that the mode was renamed astrotracer. I'll look into this and try without using my user mode.

I'd say that it almost certainly is. I suspect astrotracer will only change in B, and a user mode based on Bulb won't count.

Good luck!