[ACG]

Very informative post.
Thanks Steve

[clackers]

I have put some thought into this and I think I understand where the fellow is coming from. I admit he is thinking about things in.. a new way.

Consider a field of view for the final image that frames a Volkswagen with proper emissions control.

1 > At 28mm on a FF, we use crop mode to frame the VW. This gives us an equivalent field of view = 42mm.

2 > At 42mm on a FF, we do not use crop mode to frame the VW. But, we see the same environmentally friendly vehicle as with 28mm+crop.

Alright, the argument is that there is more detail because longer focal length is used in scenario 2 above. Maybe...

Really, I think there is more detail when the longer focal length is used and it is for this reason: In scenario 1, the FF sensor is cropped digitally. The wider view with the 28mm lens is cropped by disregarding portions of the FF sensor and we end up with the VW front and center.. In scenario 2, all the FF sensor is used. A crop is still performed but it is done optically. The wider field of view with the 28mm lens is reduced by mounting a 42mm lens... VW front and center.

So, it could be argued the 42mm lens, being longer, provides more detail. However, I think the better argument is that the 42mm lens performs an optical crop versus the digital crop made when the 28mm lens. We all know cropping with lens is better than cropping digitally...

Hi Tan,


Look back at Post 47, and you can see that's not the situation.


It's about the old Equivalence chestnut - two different format cameras at the same distance with different lenses.


There's no digital cropping being done.


The argument you, me and others have put forward - that details are dependent on how many pixels you can lay down on the target - has been rejected by 2351HD.

[osv]

Yep
The hierarchy of focus performance for all camera types stacks something like this (best at top):

1. EVF zoomed to 1:1*
   magnified live view (1:1*)
   
   less accurate:
2. Manual focus using coincidence rangefinder -or-
   split-image rangefinder -or-
   magnified ground glass at focal plane -or-
   optimized matte field (e.g. Canon S-type with fast lens) -or-
3. CDAF
4. F/2.8 PDAF (with fast lens) (generally limited to central region on high-end SLRs)
5. Microprism rangefinder
6. Stock focus screen for most dSLR cameras
7. F/5.6 PDAF

* At greater than 1:1 pixel mapping (viewfinder to sensor) the view is composed of interpolated (best guess) data.

corrected :-)

[stevebrot]

corrected :-)

It apparently works for you, but I can't believe you would make this assertion if you have experience with the other methods I placed at the #1 spot. OTOH, I don't own your camera so I can't comment on its EVF except that it should be at least as good as magnified live view on a similar pixel-pitch sensor. (1:1 from the sensor is, after all, the gold standard for focus evaluation.)

Edit: My experience has been that the other methods I placed in the #1 spot have equivalent accuracy and precision in day-to-day shooting and I have fairly deep experience with all of them. Still though...I appreciate the smiley


Steve

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Last edited by stevebrot; 03-06-2016 at 09:54 PM.

[clackers]

It apparently works for you, but I can't believe you would make this assertion if you have experience with the other methods I placed at the #1 spot. OTOH, I don't own your camera so I can't comment on its EVF except that it should be at least as good as magnified live view on a similar pixel-pitch sensor. (1:1 from the sensor is, after all, the gold standard for focus evaluation.)

I'll bet I've got the same EVF on my Sony FF as Osv's, and it's beaten hands down by the Katzeye split prism focusing screen in my K-30.

[reh321]

corrected :-)

My own experience with my lowly K-30 is that pictures I take with my old Pentax-A and earlier MF lenses are sharper than the ones I take with my AF modern lenses - which means that the focusing I'm accomplishing using the K-30's built-in "focus achieved" signal must be working well. So, I'm interested in using neither LiveView {which I find to be very awkward to use when doing manual focusing handheld} nor adding split image to my camera; personally I'll stick to what is working for me. {of course, focus-peaking is the choice by default for my Q-7, which is why I have to find room for a Hoodman in my Q-7 bag}. I guess this thread has demonstrated by now that YMMV reigns supreme in this area.

[stevebrot]

I'll bet I've got the same EVF on my Sony FF as Osv's, and it's beaten hands down by the Katzeye split prism focusing screen in my K-30.

osv does his focus evaluation at a distance of about 100 yards with a possible slight advantage over our setups. His PK/E adapter is a little shy of the 45.46mm K-mount register allowing him to rack to slightly past infinity. His demonstrated ability to attain focus with his standard subject at that distance is impressive, though it is not clear if the same could be accomplished using other methods if a little focus overrun were allowed.


Steve

[clackers]

. His PK/E adapter is a little shy of the 45.46mm K-mount register allowing him to rack to slightly past infinity.

I have the Novoflex adapter, the most expensive you can buy, if that makes any difference.

[stevebrot]

I have the Novoflex adapter, the most expensive you can buy, if that makes any difference.

Yes, it would.


Steve

[Cyril_K5]

I think one advantage no one mentions is that on the K1 you will have a little less of a diffraction issue than on the K3, so can shoot at narrow apertures for more DOF in certain instances where you want it. Should be about the same as on the K5 though.

It will certainly help with the diffraction but because you have a better DOF with APS-C at equivalent aperture, I am not sure there is a real benefit to it

[osv]

My own experience with my lowly K-30 is that pictures I take with my old Pentax-A and earlier MF lenses are sharper than the ones I take with my AF modern lenses - which means that the focusing I'm accomplishing using the K-30's built-in "focus achieved" signal must be working well. So, I'm interested in using neither LiveView {which I find to be very awkward to use when doing manual focusing handheld} nor adding split image to my camera; personally I'll stick to what is working for me. {of course, focus-peaking is the choice by default for my Q-7, which is why I have to find room for a Hoodman in my Q-7 bag}. I guess this thread has demonstrated by now that YMMV reigns supreme in this area.

i'm busting steve's chops, but i don't have enough experience with rangefinder shooting to even have a valid opinion on it

i suspect that everyone is making their own method work pretty well, due to experience... the q7 will also do 6x magnification, i think... hoodman on the lcd is a good idea regardless.

here is what it looks like with sony, pixel density matters, 14.4x(a7r) vs. 11.7x(a7)

You Tube

You Tube

people have claimed that all of the higher-end mirrorless cameras have the same epson evf, just different diopters and implementation.

if pentax delivers a clean 16x on the k1 lcd, it's gonna rock some worlds out here.

---------- Post added 03-07-16 at 12:18 AM ----------

It will certainly help with the diffraction but because you have a better DOF with APS-C at equivalent aperture, I am not sure there is a real benefit to it

i don't think so either, because when the actual dof is the same, so is the diffraction, the aperture number on the lens doesn't mean much when comparing formats... higher pixel density makes it easier to see diffraction, unfortunately, but it also increases resolution.

bigger sensors give better control over dof, but that's minor, the real gain comes from more latitude in post, better dr, and 36+ pixels increasing the resolution.

but it comes at a price... $$$, lower fps, bigger glass, etc.

[Pål Jensen]

bigger sensors give better control over dof, but that's minor, the real gain comes from more latitude in post, better dr, and 36+ pixels increasing the resolution.

but it comes at a price... $$$, lower fps, bigger glass, etc.

True, the benefit is better image quality. However, my experience from APS/FF/MF is that the larger the format the less is the control over DOF for real life images (strictly DOF control is constant; it is the usefulness of the control that varies). This is particularly evident the moment you start to use MF (in the film days many 6X7 shooters switched to LF in order to get away from the limited DOF control on the 6X7 format; they shot it constantly at F:22).
As 99,99% of all photographs that are actually taken is about getting enough DOF, transposing the DOF scale to thinner DOF such as happens from APS to FF, is a disadvantage. For most photography getting the same DOF at a larger aperture opening is a definitive bonus.

[jlstrawman]

True, the benefit is better image quality. However, my experience from APS/FF/MF is that the larger the format the less is the control over DOF for real life images (strictly DOF control is constant; it is the usefulness of the control that varies). This is particularly evident the moment you start to use MF (in the film days many 6X7 shooters switched to LF in order to get away from the limited DOF control on the 6X7 format; they shot it constantly at F:22).
As 99,99% of all photographs that are actually taken is about getting enough DOF, transposing the DOF scale to thinner DOF such as happens from APS to FF, is a disadvantage. For most photography getting the same DOF at a larger aperture opening is a definitive bonus.

I got an early start on FF with my Sony A7 II. I moved to FF primarily for the ability to adapt numerous inexpensive lenses, such as Minolta, Konica, Soligor, Vivitar,
Olympus, and of course Pentax. IMHO the IBIS and 24 MP are great features for MY shooting style. Overall, I find that consciously controlling the DOF is less important.
Despite loving the the A7 II, I pre-ordered the K-1. It will be interesting to compare the two. I may keep both.

[Clavius]

Aside from all the mentioned benefits, my small studio will become "larger" in comparison to when using an APSC camera. And thus, it will become more usable.

[cali92rs]

True, the benefit is better image quality. However, my experience from APS/FF/MF is that the larger the format the less is the control over DOF for real life images (strictly DOF control is constant; it is the usefulness of the control that varies). This is particularly evident the moment you start to use MF (in the film days many 6X7 shooters switched to LF in order to get away from the limited DOF control on the 6X7 format; they shot it constantly at F:22).
As 99,99% of all photographs that are actually taken is about getting enough DOF, transposing the DOF scale to thinner DOF such as happens from APS to FF, is a disadvantage. For most photography getting the same DOF at a larger aperture opening is a definitive bonus.

This doesn't make sense.

On your K-3, if you get an the exposure that calls for f8, 1/125, ISO 400. On you K-1, you will get the same exposure and DOF with f11, 1/125, ISO 800. Your image quality will also be the same due to the stop advantage regarding DR, noise and diffraction.

This disadvantage is that the K-1 is a lot bigger and costs a lot more than the K-3.
Also, you get more pixels per duck with the K-3.