[i83N]

I hear you.

The diffraction-limited depth of field is constant for all sensor sizes, so if it already hits you at f11 on APS-C, it will hit you even harder at f22 on FF.

It has a dependensy off the size of the pixels so the diffraction will occur later with the K-1 than the K-3. But since the sensor is larger the DOF will be shallower at a given focal length...

[Ikarus]

It has a dependensy off the size of the pixels so the diffraction will occur later with the K-1 than the K-3.

If you enter the data of the K-1 and the K-3 in the calculator here, you'll find that the K-1 at f/22 is closer to being diffraction limited than the K-3 at f/11.

But since the sensor is larger the DOF will be shallower at a given focal length...

Sure, that's why it makes no sense to compare diffraction between formats at anything other than the equivalent focal length and f-stop.

If you enter the data of the K-1 and the K-3 in the calculator here, you'll find that the K-1 at f/22 is closer to being diffraction limited than the K-3 at f/11.



Sure, that's why it makes no sense to compare diffraction between formats at anything other than the equivalent focal length and f-stop.

When I enter 24 MP crop sensor and f/8 it says Limited, f/5.6 not limited

When I enter 36 MP FF sensor f/11 it says Limited, f/8 not limited

I have made IRL tests using different lenses and visible diffraction comes later than in these calculators. Also it differs between lenses.

Using Tamron 17-50 it started 1 stop earlier than when using the Pentax 16-50.

I keep doing what I always do. I take a test shot.

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Last edited by Unregistered User; 04-08-2016 at 05:37 AM.

[noelpolar]

I to have been a bit flat awaiting the K-1, so went to the beach with my DFA 150-450 and K3 yesterday and got chased home by Zombies chanting "go home and wait for your K-1, we will not be cropped" weird..

see I'm not lying... being a bit tough I did slap them around a bit with some F14 diffraction before running home screaming like a girl.


Zombies on Goolwa Beach.jpg by Noel Leahy, on Flickr

[Zygonyx]

When I enter 24 MP crop sensor and f/8 it says Limited, f/5.6 not limited

When I enter 36 MP FF sensor f/11 it says Limited, f/8 not limited

I have made IRL tests using different lenses and visible diffraction comes later than in these calculators. Also it differs between lenses.

Using Tamron 17-50 it started 1 stop earlier than when using the Pentax 16-50.

I keep doing what I alwas do. I take a test shot.

Good practice.
I have "no-visible diffraction samples" with K20D and FA31/1.8 @ f22...

[pathdoc]

and got chased home by Zombies

They look like something from Lovecraft, coming out of the water with all the mist in the near-dark...

With all the screaming that gets done about diffraction setting in at f/11 or even lower, why do so many Pentax lenses of both older and more current vintage go to f/32? I note that almost all of my normal or near-normal Taks stop at f/16, as does a pre-A Vivitar 28/2.8 that I own, but it surprised me to see that my Rikenon 55/1.2 also stops at f/16 and that's roughly contemporary with the Pentax A lenses.

[Ikarus]

When I enter 24 MP crop sensor and f/8 it says Limited, f/5.6 not limited

When I enter 36 MP FF sensor f/11 it says Limited, f/8 not limited

Ok, it seems you also changed the print size from 10" to 24" in order to get such low limits. Anyway, the key point here is that one should not expect the K-1 at f/22 to outperform the K-3 at f/11 in terms of diffraction. So, to those folks who feel like their lowly K-3 or K-5 is not not up to snuff anymore with the K-1 on the horizon, I say this - just go out and shoot, it really ain't all that bad.

[jatrax]

Anyway, the key point here is that one should not expect the K-1 at f/22 to outperform the K-3 at f/11 in terms of diffraction.

I think most folks that have expressed an opinion seem to expect a 1 stop improvement going from APS-C to FF. Based on that I would look to see the K-1 perform better at f/16 than the k-3 at f/11. But f/22 is two stops and that might be a reach. If I understand what you are saying.

[Ikarus]

I think most folks that have expressed an opinion seem to expect a 1 stop improvement going from APS-C to FF. Based on that I would look to see the K-1 perform better at f/16 than the k-3 at f/11. But f/22 is two stops and that might be a reach. If I understand what you are saying.

For the equivalent shot on FF you have no choice but stopping down to f' = f*1.5 in order to match an APS-C camera in DOF and AOV, but diffraction at the equivalent DOF and AOV is independent of sensor size, so the K-1 will do about as well at f/16, as the K-3 does at f/11.

[mee]

I sold my K-5IIS last week. I figured by the time the K-1 arrives there would be so many for sale in the marketplace that it would be impossible to get a decent price for it. I am going through withdrawal though and do not have a film camera to fall back on. It is supposed be gray and rainy this weekend, which will help somewhat. I placed a wanted listing for a used K-3II in the market place. Maybe I will get lucky :-)

haha playing the market.. somewhat risky.

Even if you don't get a nice deal on a gently used K-3 II, you might find a K-5IIs for less than you sold it.

[loveisageless]

haha playing the market.. somewhat risky.

Even if you don't get a nice deal on a gently used K-3 II, you might find a K-5IIs for less than you sold it.

I'm actually considering forgoing the K-1 in favor of a K-3II. I recently upgraded my computer after my Mac Mini crashed. I used the Mini with a 27" Apple Thunderbolt display. The current Mini models do not allow for enough processing power, graphics capability, storage, or user memory upgrade. To get the specs I wanted (trying to future proof the new computer as much as possible) I wound up having to consider an iMac. I purchased a refurbished 27" iMac with 5K display. The Thunderbolt monitor I had was no slouch resolution wise and I would have kept it if I could have gotten what I wanted spec wise in a new Mini. Last night I was reviewing my picture catalogue on this new computer and I was absolutely floored by the resolution. The pictures I was looking at ranged from 10 to 24 megapixels files. I had no idea that the images were capable of such resolution or such a broad color gamut. Makes me think about the impact a display's resolution has on the perceived image resolution and color rendition produced by a given camera and lens. The photos indicated that the cameras used had much better resolution and color depth than I was ever aware they could produce. I had images taken with a K-10 that were stunning at 27". I don't often print photos, and when I do, they are not 27" ones, so I am rethinking whether 36 megapixels or a FF sensor are really necessary for my purposes.

[noelpolar]

I don't often print photos, and when I do, they are not 27" ones, so I am rethinking whether 36 megapixels or a FF sensor are really necessary for my purposes.

I'm similar in my thoughts, but my knees need a flippy screen......

[loveisageless]

I'm similar in my thoughts, but my knees need a flippy screen......

My knees aren't so bad, but the hereditary hand tremor is. The five axis stabilization may be the deciding factor

[noelpolar]

My knees aren't so bad, but the hereditary hand tremor is. The five axis stabilization may be the deciding factor

Yes, the K-1 could be marketed as a "Special assistance Camera" , for those that can't bend (floppy screen), see all that well (led lights), hold things steady (5 axis), forget where you are/were (GPS), have fits (flash removed), have compulsive collecting disorder (old K lenses) etc etc....