« Farmer's Rain | Main | Book of the Week: 'The Practice of Contemplative Photography' »

Tuesday, 07 June 2011


Feed You can follow this conversation by subscribing to the comment feed for this post.

Nice. They made something heavier and clunkier than my phone just for GPS... when my phone can already take GPS tagged pictures. Way to go.

I would guess it hasn't escaped your notice that all DSLRs are "heavier and clunkier" than your phone too.

In any event I'm sure no one will mind if you prefer your phone....


Interesting - I wonder how long before Pentax (or someone) offers a generic, stripped-down GPS unit that is usable on all cameras?

If you could trigger the GPS to take a reading from the flash (or pc) contact and hold the data in storage until you can download, read or print it, it would be workable with any camera made that has a way of triggering a flash.

Image such a device attached to an 8x10 camera, or mounted to an old Spotmatic! Unless, such a device already exists?

Drat. This sounds like a very useful device, but I have a K-20. Perhaps this is a good reason to upgrade and buy a K5.

"ASTROTRACER function, which couples the unit with the camera’s SR (Shake Reduction) system and enables users to photograph celestial bodies. The unit can calculate the movement of stars, planets, and other bodies using the latitude obtained from GPS data and the camera’s alignment data (horizontal and vertical inclinations and aspect) obtained from its magnetic and acceleration sensors, then shifts the camera’s image sensor in synchronization with the movement of the objects. As a result, stars and other bodies are captured as solid points rather than blurry streaks..."


OMG!   That would be, like, an invasion of my privacy!!


That sure look like the ultimate GPS gadget....reminds me of the optics used in Dune.....I wonder wether it could retrieve my Nikon lens cap I mysteriuously seemed to have lost today?

Greetings, Ed

Wonderful innovation by Pentax,...pity about the continuing lack of a 24mm f/2 after TEN YEARS of DSLR production......but presumably Pentax has its priorities...??


Chances are your cellphone uses SkyHook, not true GPS. If you want that functionality you can just buy an EyeFi card and be done with it.

That's a big ol' blob of electronics in the hotshoe! Definitely not gonna fit in the camera holster...

Yes, yes, I understand that it has its own batteries and some 50-odd channels of GPS goodness. Oh, and it converts your K-5 into a compass and way-finder and astrophotography rig... but the really interesting thing (to me, anyhow) is that it records not only where you took that picture, but also the direction you pointed the camera! Could make "seasonal landscape time-lapse" much easier, or just add a creepy CSI-factor to street photography.

@Paul Van

Jobo has made just such a device for several years now. I think with film you'd still have to jot down the time and frame number and manually match that info up later though.


Dear Folks,

Mark Banas kindly sent me the tech info.

In theory, the GPS module could track for 8 minutes pointed at the celestial north or south pole. Pointed at the celestial equator, the tracking time is inversely proportional to the focal length of the lens-- for a 30mm lens, it would be about 20 minutes.

As a point of reference, the following photograph of the center of the Milky Way:


was made in 1986 with a lens of normal angle of coverage and moderate aperture (Pentax 67 105mm f/2.4). Exposure time was only 5 minutes on ISO 400 film. A digital exposure of the same length would capture **considerably** more faint detail ...assuming a sufficiently dark sky (I was at 10,000 ft in the middle of the Pacific ocean).

This is theory-- in practice, the exposure limit is more likely to be controlled by how accurately the sensor can really determine camera position and orientation. Still, even 1 minute exposures with large aperture lenses would get results similar to my film photo.

I'd love to have a chance to try this out at some point.

pax / Ctein

O-GPS1 Specifications-

Astroarts's test ,looking great-

Dear Gleeman,

Thanks! OK, for those who didn't click thru, Pentax is claiming a maximum exposure time of 5 minutes. It is independent of focal length at the equator, but decreases with focal length at the pole. That's the opposite of what I predicted, but it is consistent with pointing accuracy rather than sensor travel being the limiting factor.

I couldn't glean much from the jpg-- to small and of low quality, plus I can't read Japanese.

Still, much appreciated info, gleeman!

pax / Ctein

So glad I recently sold my 5D Mark II for the K-5. This camera is phenomenal and keeps getting better.

Good on ya Pentax!

Now, about that 16-50 2.8 redesign...

You are welcome, pax
The spec. is using equatorial coordinate system,so it is independent of focal length at celestial poles( Declination 90°).hope this help.:)

P.S. Oops, I read the table backwards. Exposure duration is constant at the celestial poles, decreases with focal length at the equator. Ignore my comments about pointing accuracy.

pax / confused Ctein

You are welcome, Ctein
Actually, the spec. is equatorial coordinate system, so it is independent of focal length at the celestial pole(declination 90°),hope this helps.

for those who don't know how much does the astrotracer cost...
( japanese yen)

See?The O-GPS1 is a stealth me.
(and max 5min is a lot of time to k5.)
Posted by: gleeman | 

Hmmzzzz, Mark,

It also contains a function to point itself to the nearest Pentax service center. Whoops.

Greetings, Ed

The problem with hot shoe accessories is that they block the shoe. Why don't they pass the shoe through for flashes?

Ctein: note that the table represents declination, not latitude. In other words, allowed exposure time depends on what you point the lens at in the sky relative to celestial equator, regardless of camera location on Earth. The numbers look as they should.

I am also glad to have recently switched to the Pentax K5. This new tool is much more than GPS, and it will be really useful. I am looking forward to try it with the 15 Limited:)

Please check link for more photos of the astrotracer feature of the unit. Unfortunately the text is Japanese.




Hmmzzzz, Ed,

"It also contains a function to point itself to the nearest Pentax service center. Whoops."

Ha ha! Finally, a camera that annoys you with an "idiot light" and directions to the repair shop until you get some random, minor thing fixed. Why did BMW have to start us down that road? ;)

Dear Ivan,

Yeah, I said it was celestial coords in my original post.

I read the table backwards at quick glance, as my PS indicated.

pax / Ctein

Paul Van -- if I understand you, such devices have existed for years. Fairly cheap, too. Software exists to match the GPS trace stored in the GPS device up with the images using the timestamps in the EXIF data (you need to make sure your camera clock is set accurately).

Of course, since it's a separate device, it can't tell which direction you were pointing the camera.

The category name seems to be "gps logger". One brand is Holux.

I will buy one the GPS I meant, on top of the camera which has to tagged along, if it really works.

In fact, it start my research on Pentax as I plainly ignore Pentax (other than 645d and 67) camera so far. I only knew k-r and k5 beacuse this forum from time to time "off track" to Pentax :-). If it really works and just for snapshot of some wide field astro photos (50 to 200mm), it would be god sent.

Can I get away with the lowest spec one such as k-r (in orange, to match my planned purchased of Celestron C8 :-) My Mak 5 inch is too small and 1900mm/F15 is too long a focal length).

For the comparsion with iphone (which I have 10 astro programs on) and ipad etc., one must have to real and compare with how much effort to get those "bloody" tracking system work.

Piggy-back is fine but the GEM mount/tripod/goto/... it is light setup you have as one would say as it is less than 100 pound. It is heavily than my 8x10 setup by a huge margin. Can try etx backpack etc. but still it is quite a setup. All this is just to take a snapshot of the milky way, not even start to deal with real astrophotos. BG-4 ...

Hence, I am watching this very very closely. Hope it work. Please.

BTW, the latest innovation here is Astrotrac which is great because it is 2 pounds. You still have to polar aligned (why pentax need not, would it have rotation field or it compensate even the RA movement). I just bought the Manfrotto 410 yesterday to prepare to mount it when I bought it in due course. I may now wait for this development instead. They are same price. I think it is lighter as the 410 is heavier than the camera body of at least the k-r.


real world shoots from eti_forest


The time limit is related to the celestrial position not earthly position.

The comments to this entry are closed.



Blog powered by Typepad
Member since 06/2007