[Wasp]

I find the K-1 works quite well for my work. Some examples...

That's quite a cosy looking room in the third picture. I love books even more than camera gear and I can really identify with those shelves. It does make my own collection look a bit small.

One day I will get round to counting how many books I have. I did measure the shelf space the other day. It added up to twenty meters. At an average of two centimeters per book that makes it about a thousand.

[osbourne one-nil]

Thank you - I've spent quite enough recently but that won't last long!

Hopefully I'l have this camera mid-week and the amount of rain we've had over the past few days is going to mean the rivers and waterfalls are going to be looking good, so it's going to get put through its paces regardless of clear nights or not.

[MossyRocks]

If choosing between APS-C or FF with the KP or K-1ii I would base my decision on if I wanted to go wide or long. If going wide the K-1ii would be a better choice because for a given field of view you can usually get a faster lens. If you want to go deep an APS-C will better serve you as for a given field of view you can find a faster lens on APS-C. The dynamic range on the K-1ii and KP are very comparable so that is why I am focusing on lenses. As far as built in GPS vs. O-GPS1 I really haven't found a difference in results between using them . I own a K-3 and K-3ii so that is my experience and if I were looking to upgrade camera bodies I would be looking for a KP since I mostly go deep. To get the same field of view that I get with my 400/2.8 and K-3 I would have to have a 600mm lens on a K-1, but that 600mm would be at best a f/4 lens (maybe my 400mm + 1.4X-L converter) however at that point I still have lost a stop of light which the better sensor of the K-1 barely makes up for over my K-3. When comparing the K-1ii and KP sensors they are basically the same from an astrophotography perspective so figure out if you will be going wide or going deep and pick based off of that.

However don't take that as being the be all end all. Either camera would do wonderfully with any astrophotography I was just providing how I would decide which I think is fairly rational. As stated I am some one who is using K-3 and K-3ii for astrophotography and has recently been able to go wide. Here is my first non test wide shot and here is a deep shot from early last winter. Both of these were stacked shots and were taken with the K-3 or K-3ii. The Milky Way on was taken with the Laowa 12mm f/2.8 Zero-D lens and the Orion Nebula was taken the the Pentax SMC A* 400mm f/2.8 ED [IF] so I was using some exceptional glass in each case so focus more on glass than a body.

Seems to me there's three kinds of astrophotography, not that I'm any kind of expert, but from what I've seen posted, that's my conclusion. One is the wide-angle lens view showing constellations much as you'd see them with your eyeballs. The second is the mid-range telephoto view of the moon or nearby planets. The third is ultra-long-range telephoto views of distant galaxies produced by stacking hundreds of images. I don't know whether that makes any difference as to which body would be best, but it seemed to me that you might want to be more specific in case people had suggestions based on what kind of astrophotography you plan to do.

I'd note further that the KP has much greater pixel pitch than the K1, which means less dynamic range, but almost the same image data in a smaller, lighter package. But for astrophotography, I'd think you'd want as much dynamic range as possible.

I can't help thinking that the Canon EOS 5ds R, with the 50-some-odd megapixel sensor might be worth considering, particularly for your work, though it has no astrotracer or gps. The Pentax in-body image stabilization is a big plus too, though they say you should turn it off when the camera's on a tripod (I never do, because there's always something to shake things up, trucks going by or whatever).

[MossyRocks]

The second is the mid-range telephoto view of the moon or nearby planets.

The moon while being huge is really best photographed somewhere around 1000mm on a full frame (about 650mm on APS-C) as it will be close to filling the frame. Planets require even more magnification and Jupiter is pretty small even at 2000mm on APS-C. Here is a 100% crop test shot I did of Jupiter and the 4 Galilean moons with my Sigma 300mm when I first got it using my K-3. The exposure is bad (overexposed) but I was exposing for the moons not Jupiter and there is trailing because that was a 1 second untracked shot. Even with my longest setup Jupiter would only be 7 times the size which produces a some what usable image when tightly cropped. My point is that planets need really long glass but it doesn't need to be super fast since most planets are pretty bright.

M42 (orion nebula) frames up really nice at 400 and not that I have the 1.4X-L converter I can get a nicer closer frame. That shot is also pretty close to the framing one can get on APS-C but is wider in one dimension because of stackggn and not keeping it the same spot for each shot.
M31 (The Andromeda Galaxy) actually frames up really nicely in landscape with a 400mm lens on APS-C. If you thought the moon was big in the night sky the Andromeda Galaxy is huge as it is covers an area about 6 times that of the full moon. Here is a shot I made where andromeda was shot with my Sigma 300 and so was the moon, the moon was poorly pasted in to just show the relitive size of each since they were shot with the same lens. This is actually a really bad edit so a lot of the fine detail was lost as andromeda is bigger than what is shown. Here is a better edit of andromeda shot with a 300mm lens so you can have an idea of what it looks like.
As far as smaller galaxies go here is a shot of M51 (the whirlpool galaxy) shot with my 400mm but is cropped so it is probably about 50% bigger than it would be in an actual single frame. To see what it kind of looks like in a single shot at 400mm there is this shot of it I took on my first attempt with that lens.
For giggles here is a stacked and stitched panorama of a full moon taken at 2000mm. Since I had a lot of shots to play with I did a 2x upsampling before stacking and stitching to see if I could pull out more detail. The full size image is 12,000x12,000 and here is a 100% crop from that shot.
I don't have any non ultrawide wide astro shots but I know that in the 35mm to 50mm range you can frame up most constellations on APS-C and even big ones like Orion you can get entirely in frame on APS-C. Since at these focal lengths really fast good lenses are easy to come by it doesn't matter what body you are using.

I'd note further that the KP has much greater pixel pitch than the K1, which means less dynamic range, but almost the same image data in a smaller, lighter package. But for astrophotography, I'd think you'd want as much dynamic range as possible.

The K-1ii has a bit more dynamic range than the KP does at the same ISO. A while back I did some digging and was surprised at how close things are between them. Here is the resource I found but you have to select the K-1ii and KP. The fact that at the ISOs one would use for astrophotography (max of some where around 6400) there is well less than a stop difference in dynamic range. So this is why I pose it as a question of wanting to do more ultrawide or do more deep shots. For ultrawide one would be better served by the K-1ii because you end up with faster glass for similar field of views by usually a whole stop, just like on the deep end one gets similar field of views with the KP with glass that is faster by a stop. If you are thinking of staying between about 35mm and about 200mm (you can do some pretty reasonable deep sky objects at 200mm) it doesn't matter what body you use but the slight advantage that the K-1ii has would be of a benefit. In either case the K-1ii or KP would outperform my K-3 and K-3ii which is why I may get the K-new as that should be even better for someone like me who mostly goes deep.

[osbourne one-nil]

Thanks both - fantastic photos too.

I'm definitely a wide-angle milky way with a bit of landscape thrown in sort of guy. My telescope is a plain and simple dobsonian with no electronics at all but I prefer binoculars these days as they take me to locations I could never go with a telescope and show the stars in context if they're near the horizon...or if you view them through gaps in trees/clouds etc. I'm full of admiration for people who take stunning photos of nebulae etc, but that's not me. I haven't the time or inclination and the weather makes it well nigh impossible here anyway. Also, photos like that, while impressive, don't reach out to me as they're a bit....sterile? A nebula looks the same every night but only I can get that shot of the Orion rising behind a Lake District Fell...if you get me?

I think that makes my (with retrospect, inevitable) choice of the K-1 even more sensible, as the 24-70mm lens will give me 24mm...not 36mm.

The K-new might be badly timed for me!

[MossyRocks]

A nebula looks the same every night but only I can get that shot of the Orion rising behind a Lake District Fell...if you get me?

I fully understand that. Wide and ultrawide astro shots are very different from deep sky objects, especially when capturing things in the foreground. I'm all for theoretically spending other people's money but will at least try to be thoughtful about it. You mentioned a 24-70 but I would highly recommend looking at primes. Primes have less distortion, generally are faster, generally have better transmission, and also generally have less CA. That isn't to say you can't do astro with a zoom but you will likely get better results with a prime, even an older one. For good results even going wide stacking is always a good idea as you can really drive down the noise so the lower distortion from a prime helps a lot here too. If going ultrawide (like with my 12mm) astrotracer may make a mess of things as it works like a alt-az mount that also does field rotation. However crossing the celestial equator in the frame or having high distortion really messes with things. The good thing is that you can get by with long untracked exposures without noticeable trailing. The milky way shot I linked to was a stack of 143 shots each 13 seconds long that were shot wide open at f/2.8. I would not use astrotracer with a fisheye as that seems like something that will end in a hot mess fast.

[MossyRocks]

A nebula looks the same every night but only I can get that shot of the Orion rising behind a Lake District Fell...if you get me?

I fully understand that. Wide and ultrawide astro shots are very different from deep sky objects, especially when capturing things in the foreground. I'm all for theoretically spending other people's money but will at least try to be thoughtful about it. You mentioned a 24-70 but I would highly recommend looking at primes. Primes have less distortion, generally are faster, generally have better transmission, and also generally have less CA. That isn't to say you can't do astro with a zoom but you will likely get better results with a prime, even an older one. For good results even going wide stacking is always a good idea as you can really drive down the noise so the lower distortion from a prime helps a lot here too. If going ultrawide (like with my 12mm) astrotracer may make a mess of things as it works like a alt-az mount that also does field rotation. However crossing the celestial equator in the frame or having high distortion really messes with things. The good thing is that you can get by with long untracked exposures without noticeable trailing. The milky way shot I linked to was a stack of 143 shots each 13 seconds long that were shot wide open at f/2.8. I would not use astrotracer with a fisheye as that seems like something that will end in a hot mess fast.

[osbourne one-nil]

I think that's the great thing about the Pentax cameras. An ultra-wide doesn't need (or can't use) astrotracer, but it's then for lenses that can. I could even get a Skywatcher tracking mount or nab someone's equatorial mount for a few nights. I've got lots of options.

I'll definitely be in the market for a prime or two once I'm used to the camera, but I think the 24-70 will be SO versatile that it will cover most of my needs on most occasions. A prime 50mm lens would make sense for my professional work, but something like a 12mm or 15mm ultrawide would be so much fun!

[MarkJerling]

PS - Mark....lovely shots (and house). It seems silly that I've spent the last few years walking in some spectacular scenery armed with nothing more than a mobile phone. What was I thinking?!

Thanks! Sometimes a phone works because it's the only thing you have on you. Other times....

[MarkJerling]

That's quite a cosy looking room in the third picture. I love books even more than camera gear and I can really identify with those shelves. It does make my own collection look a bit small.

One day I will get round to counting how many books I have. I did measure the shelf space the other day. It added up to twenty meters. At an average of two centimeters per book that makes it about a thousand.

My client has quite a collection of books. I wish we had a room like that. In our house, we have a fair number of bookshelves but they're spread out all over the house. I have not counted or catalogued although it would not be a bad idea as I sometimes struggle to find a book that I think is on one part of the house but turns out being somewhere else!

[osbourne one-nil]

Ah - you should have pretended it was your house (although I'm sure yours is lovely too). My dad died recently leaving about 2000 classical vinyl albums and thousands of books, including classics like 4mm Coal Wagon Finescale Modelling volume 2. I might begin to appear very educated in the coming months one I learn how to make bookcases.

I can't wait to get out in the evenings and put this thing through its paces; it doesn't get dark until about 10.30 which gives me plenty of time for a nice leisurely lakeside walk. I think a ND filter might be my first addition.

[disasterfilm]

You mentioned a 24-70 but I would highly recommend looking at primes. Primes have less distortion, generally are faster, generally have better transmission, and also generally have less CA. That isn't to say you can't do astro with a zoom but you will likely get better results with a prime, even an older one.

Definitely agreed here! I haven't tried the D-FA 24-70 for any type of astro photos, but maybe I'll give that a spin my next time out.

Just spitballing here, but I believe that for the price of the D-FA 24-70, you could probably find a D-FA 28-105 + Roki/Samyang 24 f/1.4. That would give you tons of versatility with the standard zoom, and a 2nd-to-none option for wide field photos of stars. The 28-105 really is spectacular in its own right. Just an extra option to consider! On the US market, especially used, it would be less expensive to go with the dual-lens option.

[osbourne one-nil]

Much slower lens though (is that the right term) so would require longer exposures and/or higher ISO...or so I figured. I've decided I'm going to try really hard to win the lottery this weekend anyway so I'll then be able to buy whatever lens I want!

[disasterfilm]

Much slower lens though (is that the right term) so would require longer exposures and/or higher ISO...or so I figured. I've decided I'm going to try really hard to win the lottery this weekend anyway so I'll then be able to buy whatever lens I want!

Yes, you've got that right! It's a slower lens.

I consider practical usage though when comparing lenses. Not everything needs to be shot wide open, and there are often benefits to stopping down the lens. When shooting architectural/cityscape/landscape, I'll often stop down to f/5.6 or f/8 anyway, regardless of what lens I'm using. Particularly if you're on a tripod, or if the shutter speeds are still good enough to hand-hold.

I pretty much never shoot the D-FA 24-70 at f/2.8. Most of the time I'm f/4 or further down. Not trying to talk you out of anything! Just trying to illuminate other things to consider before you start spending that lottery money.