[oldstoat]

Having been a pentaxian since the days of film I have quite a few lenses and bellows and extention tubes. I am thinking of upgrading, but do not know whether to buy a K3 or K3ii or go whole hog and save even harder for the FF K1, my main interests are macro and ornithology, I would like to get into astrophotography and already have the telescope and convertors to attach pentax to the telescope.

So would be really grateful for any thoughts on the matter

Cheers

[Na Horuk]

That's a very good answer right there.
Basically, the APSC cameras have a slight "magnification bonus", which might make them better for macro and telephoto.
The K-1 is a slightly bigger camera and has some innovative features and a tilting screen, and even those LED lights to help in dark.

I would recommend you go to a store where you can hold both cameras in your hands. Maybe that will give you the final push to decide.

[Oakland Rob]

You can get some dandy glass with the price difference....

The K-1 definitely has an edge for big prints, dynamic range, probably autofocus in hard situations, shallow DOF. Has wifi, tilt screen. But needs FF lenses ideally. Heavier. Pricier.

The K-3II is lighter, faster burst mode, and cheaper. Works with all those APS-C lenses. More forgiving on DOF for those macro shots.

I don't think you'd go wrong with either; the big difference will be $$.

[surfar]

A used k3,a new k1...or a new k3ii and wait andxsee if K1 prices drop? (It wont be soon)

[DeadJohn]

...I would like to get into astrophotography and already have the telescope and convertors to attach pentax to the telescope...

What telescope and what mount? Astrophotography through a telescope needs very good tracking. Google "autoguiding" for more info.

You can get some dandy glass with the price difference....

The K-1 definitely has an edge for big prints, dynamic range, probably autofocus in hard situations, shallow DOF. Has wifi, tilt screen. But needs FF lenses ideally. Heavier. Pricier.

The K-3II is lighter, faster burst mode, and cheaper. Works with all those APS-C lenses. More forgiving on DOF for those macro shots.

I don't think you'd go wrong with either; the big difference will be $$.

About the DOF. The sensor size has no impact on DOF. What impacts is distance, aperture and focal length.

[slip]

I would hold out until the K1 drops in price.

Randy

[clawhammer]

Having gone from a K10D to a K5 myself, I can tell you that either camera is going to be a massive improvement. The K10D is a good camera, but the newer cameras are slicker, faster, auto-focusier, auto-exposurier, comfortablier, and all-around cameraier.

[Rickster]

I was going to get the K-1 but after a bit of thinking about It I opted for the K-3 II - I'll revisit a K-1 purchase next spring. So far I'm thrilled with the K-3 II - awesome camera.

[Ikarus]

About the DOF. The sensor size has no impact on DOF. What impacts is distance, aperture and focal length.

Sure, except that in order to match FOV and DOF of a FF 50mm f1.4 shot, one needs a 35mm f1.0 on APS-C, so good luck with that!

[oldstoat]

What telescope and what mount? Astrophotography through a telescope needs very good tracking. Google "autoguiding" for more info.

It's a 6" refractor with alt azi mount Then placed on a brick column rather than a tripod

---------- Post added 05-29-2016 at 09:15 AM ----------

About the DOF. The sensor size has no impact on DOF. What impacts is distance, aperture and focal length.

I have two lenses from 35mm film days so would they act as FF lenses on the K1

---------- Post added 05-29-2016 at 09:17 AM ----------

You can get some dandy glass with the price difference....

The K-1 definitely has an edge for big prints, dynamic range, probably autofocus in hard situations, shallow DOF. Has wifi, tilt screen. But needs FF lenses ideally. Heavier. Pricier.

The K-3II is lighter, faster burst mode, and cheaper. Works with all those APS-C lenses. More forgiving on DOF for those macro shots.

I don't think you'd go wrong with either; the big difference will be $$.

I have two lenses from 35mm film days so would they act as FF lenses on the K1

It's a 6" refractor with alt azi mount Then placed on a brick column rather than a tripod

---------- Post added 05-29-2016 at 09:15 AM ----------



I have two lenses from 35mm film days so would they act as FF lenses on the K1

---------- Post added 05-29-2016 at 09:17 AM ----------


I have two lenses from 35mm film days so would they act as FF lenses on the K1

Yes, 35mm=FF.

---------- Post added 05-29-16 at 02:28 PM ----------

Sure, except that in order to match FOV and DOF of a FF 50mm f1.4 shot, one needs a 35mm f1.0 on APS-C, so good luck with that!

And 50mm f/1.4 has to do with DOF in macro work in what way?

[Na Horuk]

Sure, except that in order to match FOV and DOF of a FF 50mm f1.4 shot, one needs a 35mm f1.0 on APS-C, so good luck with that!

And to match a 300mm (not to mention 450mm, 560mm) on APSC with good DoF, you need a monster of a lens on FF! And to match the extra magnification from APSC you get in macro range (virtually pushing you beyond 1:1) you need an enlarger lens! Good luck with those!
Matching different formats is Sisyphus' errand

[normhead]

Macro and ornithology has K-3II written all over it.
IN the APS-c crop area, the K-1 is 15 MP, the K-3II is 24 MP.
With the same lens, you will get more subject magnification with the same lens.
To make up for the less magnification on a K-1 you'll have to use the whole frame and more magnification. By the time you've used the better ISO to compensate for the loss of DoF, you'll also have lost your shutter speed an noise advantage. For those two things, a K-3 is probably just as good as the K-1 for a lot less money. Although, if you do everything needed, like use a longer local length lens, set up your image so you don't crop etc. etc, you will get a better image on the K-1.

Images like this image taken with the K-3 DA*200 and F1.7x AF adapter, for 340mm, you are going to need a Sigma 500 4.5 on a K-1 to do the same field of view.

Original image



Final crop


My 200 with 1.7x is quite portable. The Sigma 500 4.5, not so much.
To get the higher resolution with a K-1 there's a price far beyond the price of the camera. Since the K-3 already resolves the feather detail, I'm not even too sure you'd get anything from that extra 25% of detail.

The total cost of my DA*200 and 1.7 TC, which gives me 340mm ƒ4.5 is around $1200 CAD. The Sigma 500 is $7,500 CAD plus $2500 CAD = $10,000 for a K-1 setup. For me, i can afford the K-3 set up, not the K-1 set up. Resolution is a wonderfull thing, but it costs you 4 times the price, hoping that everything will line up, and the gods will smile, and you "nail one" and get a superior image.

Personally, if someone starts buying my images I'll go for it. Until then it's unlikely. I'm only willing to put that kind of money into something that can make me money.

But if you have the 10k lying around and strong back... go for a K-1

[Ikarus]

And 50mm f/1.4 has to do with DOF in macro work in what way?

Not in the least. I was responding to the following statement of yours: "The sensor size has no impact on DOF." If that was meant to say "The sensor size has no relevance for DOF when one is not operating at wide open aperture.", we have no disagreement.

---------- Post added 05-29-16 at 11:41 AM ----------

And to match a 300mm (not to mention 450mm, 560mm) on APSC with good DoF, you need a monster of a lens on FF! And to match the extra magnification from APSC you get in macro range (virtually pushing you beyond 1:1) you need an enlarger lens! Good luck with those!

Yes, aka flip-side of the coin. For tele work, APS-C is definitely compelling. For shallow DOF, I'd go with FF.

Matching different formats is Sisyphus' errand

To me it's less about matching them than knowing your trade-offs and one thing that's important to understand is that they really are significant only for the corner cases (low light, long distance, shallow DOF, high magnification, etc). For everything in between, i.e. the vast majority of shots, people will be hard-pressed to tell the difference between APS-C and FF.