[brenski]

thanks Grimmus, now the Focal Length popup is appearing, I'll try again later and see what ensues

[mlag]

Hi, please excuse this post, but I'm completely new to Pentax cameras and (in particular) the Astrotracer functionality (all of my photography experience being Canon-based).

I've just purchased a Pentax K-3 II and I'm hoping to get some good astro imaging done.

Can anyone help with:
♦ Complete step-by-step setup for Astrotracer, including GPS, Bulb mode and imaging.
♦ I've read (somewhere) that configuring the lens is important, if so, why? and how is this done?
♦ Remote Android control of Camera

Any other settings required? ie white balance, colour etc?

thanks

Probably late with this but there is starter's info here
https://pentax.eu/blogs/news/the-astrotracer-on-the-pentax-k-3-mark-3-recomm...otography-tips
At bottom of article there is reference to other websites...

[brenski]

hi, thanks - but much of that does not appear on the K3II menu system

[Grimmus]

now the Focal Length popup is appearing, I'll try again later and see what ensues

Yeah, I suppose if you are not getting this popup, the camera is making an uneducated guess at the focal length, and there's a lot to choose from so would be invariably wrong
I've noticed that it usually suggests what I put in last time when I use a manual lens, so presume it makes the same assumption for astrotracer....but I digress.......

[brenski]

Hi Grimmus

I've got a Takumar Asahi 300mm f4 on order. this has a good reputation for astro results.

I'll be looking into the Sigma you mentioned too.

My Hoya 200 just doesn't reach infinity on the Pentax (it does on my Canon). - it's an M42 with a K adapter

[Grimmus]

Hi @brenski, you should have a poke around in the astrophotography group, lots of info over there if you haven't already.
Including images from testing on various lens options in this thread
The Great Astro Lens Test - Astrophotography - PentaxForums.com

[brenski]

Hi @brenski, you should have a poke around in the astrophotography group, lots of info over there if you haven't already.
Including images from testing on various lens options in this thread
The Great Astro Lens Test - Astrophotography - PentaxForums.com

thanks, but I don;t appear to be able to post there:
https://www.pentaxforums.com/forums/group.php?do=message&groupid=135
You must be a group member to perform this action.

latest update, and it ain't good news, feel like giving up on this as a bad job. star shape is awful and halos are terrible.

GPS Calibrated (correctly) = Yes
Astrotracer On = Yes
Focal Length Set = 135mm
Lens = Asahi TAKUMAR Bayonet 135MM F2.5
Focused correctly using Bahtinvov
Astrotracer suggested I could capture around 1'15" - these are only 20" captures and they're a mess.

100x 20s stacked images @ iso 400 / F/4.0
(jpeg for illustration only)




here's the link to the stacked tif file:
test.tif - Google Drive

I'm lost on this one. almost thinking about giving up and trying to recover some of my investment

[Wheatfield]

I have done very, very little night sky photography, but I've done enough reading to suspect that lens selection is of critical importance since this is pure technical photography, and not all lenses are up to the task.
For example, the below shot was done with the D FA*85/1.4 lens wide open for 10 seconds at ISO 800 using the Astrotracer function on the K1.
I processed this particular image with the Enhance tool in Lightroom which increases the number of pixels four times, effectively rendering a 144mp image.
The lens is sharp wide open, allowing me to have as much light gathering capability as possible.



By contrast: Same night, same location, same camera, but this is with the DFA 70-210/4,
at 200mm, 20 seconds, f5.6 and ISO 6400.