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06-21-2016, 03:03 PM - 1 Like   #31
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QuoteOriginally posted by biz-engineer Quote
But the thing is, I can also get closer like you ... so in the end, apsc can't catch up, never, not possible.
Maybe, maybe not. Listen, don't argue with me, get off your lazy ass and try it.

Why do I want more blur on a shot like this?

At that point does the "more blur" make the picture look different.

And as pointed out above, you can't just open up the camera and leave large parts of the subject out of focus, you have to have a certain amount of DoF, and at that point equivalence kicks in and stays with you.

The only images for which this would be true ( an advantage for FF) would be images where you can endlessly reduce your DoF, without your subject portion of the image suffering. Like a 2D test chart. Even when shooting for narrow DoF, I rarely shoot my lens wide open. The only place where FF would have the advantage would be the circumstance where you are shooting wide open, and your subject is flat. IN the example photographs, unless the photographer shot wide open, you can do exactly the same thing with APS-c. If they shot 85mm ƒ2, you can shoot 55mm ƒ1.4. Of the possible ƒ-stops that could be used, only 85mm ƒ1.4 couldn't be reproduced on APS-c, and there is a very real possibility that set up would not produce an acceptable image. There are reasons why people don't shoot everything wide open. And you have no idea looking those images what ƒ-stop was used. They could easely be shot at ƒ4 and well within the capability of any APS-c 2.8 lens.

There is nothing to suggest the example images were shot wide open.

IN all my time on the forum I have seen one image where the person who posted showed it couldn't be done on APS-c, and he claimed there was wall behind him and he couldn't back up. My suspicion is he lied about that.


Last edited by normhead; 06-21-2016 at 03:18 PM.
06-21-2016, 03:41 PM   #32
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QuoteOriginally posted by alamo5000 Quote
At some point this stuff just gets pointless and old. After a certain point lenses won't focus anymore. Also after a certain point lenses will have such a shallow DOF that the person's nose might be the only thing in focus.
Wait a minute. We aren't shooting people at 10 inch from them. So, at 20 feets even with a fast lens, DoF is non issue. Once again, I was referring to photographing people, not small birds, cats or flowers at 2 feet distance. Saying it's pointless completely misses the photographic goal.

---------- Post added 22-06-16 at 00:44 ----------

QuoteOriginally posted by normhead Quote
Why do I want more blur on a shot like this?
I have no problem creating blur shooting birds at f8 450mm. There is no risk to create this same amount of blur when shooting people except if their body would be floating in space or suspended to a cable. Usually, people have to stand on their feet so the background isn't 200 yards away from the subject.
06-22-2016, 05:54 PM - 1 Like   #33
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I couldn't care less about the relative ability of APS-C and FF to obliterate backgrounds into unrecognizability with a subject 1-2 feet away with the background like 20 feet away. That proves nothing. My m4/3 could easily do that and more with a significantly smaller kit than APS-C DSLRs. Even a cheap P&S can produce a similar effect under those circumstances

I have not had the K-1 long enough to find specific shots that could not be closely replicated with APS-C under the circumstances which they were taken, but in the past I have had various instances where achieving the DoF on I wanted on the K-5/K-3 was no problem, but I was unable to capture the field of view that I wanted because of the limitations of K-mount fast wide angles. Take this shot that I was disappointed with for example:



This was shot with the K-5 with the Sigma 35mm f/1.4 Art. This was before the 18-35mm was available, and thus one of the very few options for fast kinda-sorta-not-really-wide on APS-C K-mount. The point of it was to capture the irony of the kid walking right past the "No Sliding" sign with a toboggan. Wide angle shallow DOF was necessary as the background was full of tons of detail that would make it hard to isolate the subjects, but I didn't want to obliterate the background so the environment and location were still readily apparent (Mount Rainier National Park). Yet the shot was not what I wanted because I could not fit the whole body of the kid in the frame, along with the sign, nor was there any in-focus portion of the ground (which would've been right under the kid's feet).

This was a very quick shot for which I only had a few seconds window (no time for elaborate setups/techniques). No, I could not have "zoomed with my feet" (which is a complete fallacy by the way, altering the picture's perspective and DOF), as that would involve making my way down a steep snow slope, by the time of which the kid would be long past the sign, and/or my gear and I would've tumbled down. The 18-35mm might've gotten a similar, but not as shallow, effect, but it did not exist for K-mount at that time, not to mention the unpredictable AF and AE of that lens may or may not have cooperated at that instant (I know, having owned that particular lens since it came out). A 16-50 f/2.8 would have produced a very subtle shallow DOF effect that would not be apparent except at high magnification.

But using a bit of extrapolation, this picture would've been exactly what I wanted if shot with this exact same lens, same settings, same location and circumstances with a FF camera (well, except for the nervous bokeh quality that I never liked on the Sigma 35 Art).

The other thing that is impossible to replicate with APS-C DSLRs is astrophotography, where absolute aperture diameter (not f-number) is king for light gathering power on stars. Ask any astronomer which is better at gathering light, the Hubble Space Telescope with its f/24 (that's "twenty four") focal ratio or an iPhone with an f/2.4 ("two point four") lens. There is no substitute for a 24mm f/1.4 lens on FF on any smaller format (or even with 645 MF for that matter) in terms of AOV and light gathering power, nor for the upcoming Irix 15mm f/2.4 that I am very much looking forward to. I have tried with 12mm f/2 on m4/3, and the Sigma 10-20 f/4-5.6 and 18-35mm on APS-C and come up with decent looking photos at low magnification with heavy post-processing, but definitely wanting more.

You should in theory be able to do neat tricks like capture more point light sources, like stars, without adjusting exposure for non-points like the moon. This is because point light sources (on the scale of 1 pixel or smaller) are controlled by absolute aperture diameter, while controlling exposure on distributed objects are by f-number (normal exposure). In theory it should be possible to adjust exposure to get more stars to appear without further blowing out the moon in a shot like this if it were taken with a 15mm f/2.4 on FF, rather than the 10mm f/4 on APS-C that it was (that's a quarter moon in the center):


Last edited by Cannikin; 06-22-2016 at 06:48 PM.
06-24-2016, 02:55 PM - 2 Likes   #34
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QuoteOriginally posted by Cannikin Quote
I couldn't care less about the relative ability of APS-C and FF to obliterate backgrounds into unrecognizability with a subject 1-2 feet away with the background like 20 feet away. That proves nothing. My m4/3 could easily do that and more with a significantly smaller kit than APS-C DSLRs. Even a cheap P&S can produce a similar effect under those circumstances

I have not had the K-1 long enough to find specific shots that could not be closely replicated with APS-C under the circumstances which they were taken, but in the past I have had various instances where achieving the DoF on I wanted on the K-5/K-3 was no problem, but I was unable to capture the field of view that I wanted because of the limitations of K-mount fast wide angles. Take this shot that I was disappointed with for example:



This was shot with the K-5 with the Sigma 35mm f/1.4 Art. This was before the 18-35mm was available, and thus one of the very few options for fast kinda-sorta-not-really-wide on APS-C K-mount. The point of it was to capture the irony of the kid walking right past the "No Sliding" sign with a toboggan. Wide angle shallow DOF was necessary as the background was full of tons of detail that would make it hard to isolate the subjects, but I didn't want to obliterate the background so the environment and location were still readily apparent (Mount Rainier National Park). Yet the shot was not what I wanted because I could not fit the whole body of the kid in the frame, along with the sign, nor was there any in-focus portion of the ground (which would've been right under the kid's feet).

This was a very quick shot for which I only had a few seconds window (no time for elaborate setups/techniques). No, I could not have "zoomed with my feet" (which is a complete fallacy by the way, altering the picture's perspective and DOF), as that would involve making my way down a steep snow slope, by the time of which the kid would be long past the sign, and/or my gear and I would've tumbled down. The 18-35mm might've gotten a similar, but not as shallow, effect, but it did not exist for K-mount at that time, not to mention the unpredictable AF and AE of that lens may or may not have cooperated at that instant (I know, having owned that particular lens since it came out). A 16-50 f/2.8 would have produced a very subtle shallow DOF effect that would not be apparent except at high magnification.

But using a bit of extrapolation, this picture would've been exactly what I wanted if shot with this exact same lens, same settings, same location and circumstances with a FF camera (well, except for the nervous bokeh quality that I never liked on the Sigma 35 Art).

The other thing that is impossible to replicate with APS-C DSLRs is astrophotography, where absolute aperture diameter (not f-number) is king for light gathering power on stars. Ask any astronomer which is better at gathering light, the Hubble Space Telescope with its f/24 (that's "twenty four") focal ratio or an iPhone with an f/2.4 ("two point four") lens. There is no substitute for a 24mm f/1.4 lens on FF on any smaller format (or even with 645 MF for that matter) in terms of AOV and light gathering power, nor for the upcoming Irix 15mm f/2.4 that I am very much looking forward to. I have tried with 12mm f/2 on m4/3, and the Sigma 10-20 f/4-5.6 and 18-35mm on APS-C and come up with decent looking photos at low magnification with heavy post-processing, but definitely wanting more.

You should in theory be able to do neat tricks like capture more point light sources, like stars, without adjusting exposure for non-points like the moon. This is because point light sources (on the scale of 1 pixel or smaller) are controlled by absolute aperture diameter, while controlling exposure on distributed objects are by f-number (normal exposure). In theory it should be possible to adjust exposure to get more stars to appear without further blowing out the moon in a shot like this if it were taken with a 15mm f/2.4 on FF, rather than the 10mm f/4 on APS-C that it was (that's a quarter moon in the center):


And I could care less that you could care less...


It's not about replicating anything. It's about seeing any kind of difference between the two, other than theoretically and mathematically in practical everyday photographic results.


I'm glad you are convinced FF is going to solve all your problems. For most it's going to make no difference whatsoever, except be heavier, cost more and eat up hard drive space.


Back in the film days, most people didn't argue that they needed medium format, 35mm did what they needed it to do. Today, Aps-c far exceeds the possibilities of anything 35mm film was capable of, yet people seem to think they all need FF to solve some mythical shortcomings of APS-c. Yes, the emperor is missing some garments... sorry.

06-24-2016, 03:16 PM   #35
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^^ The control factor being "with the lenses I already own." For those of us who own primarily or exclusively traditional FF lenses APSc most assuredly does not render the same images as FF, other environmental factors being the same.
06-24-2016, 03:41 PM   #36
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here's my 1$ reply: spend more money, earn more money. and vice versa.

06-24-2016, 09:37 PM   #37
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QuoteOriginally posted by biz-engineer Quote
The amount of blur is different from the depth of field. The blur depends on diameter of the entrance pupils, placement of subject relative to hyper-focal distance. Depth of field can be the same regardless of the diameter of the entrance pupil. Most people confuse both. If I use a 200mm f2 wide open, there is no way you can achieve the same background blur with a 50mm lens because you would need a 50mm f0.25 lens which does not exist. And if you use a 500mm f4, there is no way you can achieve the same completely smooth background with a 85 f1.4 lens. Therefore there is a gap between formats that can only be close via stitching, and when stitching can't be done, it is wrong to say that two different format can produce the same result. That's physically not possible. Interesting to see people defying the laws of physics for emotional reasons.


It's not about defying the laws of physics, it's about actually being able to see what your talking about in a print. Try it. And show the world your results. Good luck.


Interesting to see people go through such pains to justify their purchases.


It goes both ways.

---------- Post added 06-24-16 at 10:44 PM ----------

QuoteOriginally posted by monochrome Quote
^^ The control factor being "with the lenses I already own." For those of us who own primarily or exclusively traditional FF lenses APSc most assuredly does not render the same images as FF, other environmental factors being the same.


But the differences are minimal at best. You would have a really hard time demonstrating these FF vs. APS-c renderings to anyone. Iso 3200 will look the same as 1600 on APS-c, so that might be easy, but that's about it.


If you have a shed load of old FF K mount lenses, then clearly the K1 is heaven sent, no doubt about it. If you don't, then the K1 is just not that compelling...
06-24-2016, 10:41 PM - 1 Like   #38
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QuoteOriginally posted by Qwntm Quote
But the differences are minimal at best. You would have a really hard time demonstrating these FF vs. APS-c renderings to anyone. Iso 3200 will look the same as 1600 on APS-c, so that might be easy, but that's about it.
I'm not a professional photographer, but I read that agencies often refuse to consider APSc images. Why is that?

What everyone forgets is, to achieve the same perspective using two formats the distances to subject and subject to background differ significantly. It is not possible to duplicate a photograph standing in one place with a FF camera and an APSc camera using the same FL lens.

Then comes the argument about equivalence, devolving into a discussion of different fields of view, focal lengths, apertures and ISO's, by which time it must be inferred that saying one could theoretically duplicate a FF photograph with completely different equipment, settings and unlimited space is not the same thing as asserting a FF camera is not necessary.

06-25-2016, 03:59 AM - 1 Like   #39
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QuoteOriginally posted by Qwntm Quote
If you have a shed load of old FF K mount lenses, then clearly the K1 is heaven sent, no doubt about it. If you don't, then the K1 is just not that compelling...
The best is fuji , one of the highest priced apsc system that you praise on youtube photouniverse channel, i.e $1700 Euros for an 24Mpixel apsc camera such as Xpro2 ($200 less than a 36Mpixels K1 DSLR) + the cost of $500 to $800 for each of the bunch of primes you have to buy to try to get closer (but not quite) to full frame image quality.
06-25-2016, 05:16 AM   #40
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About the original question:

There are rather simple connections which are mirrored and valid all the time:

Larger sensor can be emulated 100%* by either
a) wide angle converter lens on large image circle lens on small sensor OR
b) sticking together ("panorama stitching") more images from small sensor. In theory 2 images** mean double size mean +1 stop

Small sensor can be emulated 100%* by either
a) tele coverter lens on small image circle lens on large sensor OR
b) cutting out ("cropping" / "digital zoom") one image form large sensor. In theory cropping to 1/2 the area means -1 stop.

This all is the result of the factor "magnification".

*=Noise, background blur, DoF, resolution, CAs
**= in practise you will take 3 images with overlap since automatic stitching will not work with zero overlap.

In practise stitching is difficult with moving targets.
In practise optical FF viewfinders with only crop mode used are smaller.
In practise tele converters negatively affect AF performance.
In practise wide angle converters only work on mirrorless APSC cameras.
In practise you get the best background blur at infinity using Sigmas lens at 500mm F2.8 as the aperture of 179mm is unrivalled.
In practise the open space to use is limited, so the background blur at infity sometimes is less relevant than the background blur with a close background and in this scenario results can turn around completely.
06-25-2016, 09:14 AM   #41
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QuoteOriginally posted by Qwntm Quote
And I could care less that you could care less...


It's not about replicating anything. It's about seeing any kind of difference between the two, other than theoretically and mathematically in practical everyday photographic results.


I'm glad you are convinced FF is going to solve all your problems. For most it's going to make no difference whatsoever, except be heavier, cost more and eat up hard drive space.


Back in the film days, most people didn't argue that they needed medium format, 35mm did what they needed it to do. Today, Aps-c far exceeds the possibilities of anything 35mm film was capable of, yet people seem to think they all need FF to solve some mythical shortcomings of APS-c. Yes, the emperor is missing some garments... sorry.
I did not say it will "solve all my problems". I have pictures I want to take with certain results. I have clearly identified several instances where APS-C did not get me my desired result (e.g. the framing/composition-DOF dichotomy in my first picture), or where it is unambiguous fact that FF will achieve closer to the (unachieveable) ideal (e.g. astrophotography) for optical (the same principles that apply to telescopes that are much older than modern photography) and practical reasons (fast and wide APS-C lenses are few and far between, especially for DSLRs).

If I am just walking around, not trying to achieve a specific photo that I know FF will be better suited for, my m4/3 kit is significantly smaller, lighter, and more reliably focusing (not necessarily faster, but almost never have problems with back/front focusing) than my K-3 and K-5, while achieving very similar IQ (the difference between m4/3 and APS-C is less than the difference between APS-C and FF). The only thing my APS-C DSLR is better suited for than either now is fast action, which I rarely shoot nowadays.

I have a 5-foot-wide, highly detailed, landscape panorama hanging on my wall right now, daylight and low light landscapes, super shallow DOF flower shots, action shots etc. all of which I'm pretty sure no one could determine which format I used just by looking at them (other than aspect ratio), all shot with APS-C and m4/3 until now, so I know very well what smaller formats are capable of, as well as the situations where they did not quite get what I wanted.

I've done my research, as I'm sure many others have. I don't much appreciate thinly veiled, condescending implications that people who want FF are merely fooling themselves.

Last edited by Cannikin; 06-25-2016 at 09:48 AM.
06-25-2016, 11:22 AM - 3 Likes   #42
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QuoteOriginally posted by ChristianRock Quote
The site linked in the original post shows pictures that have had a lot of PP done to them. Including some PP to blur the background beyond what was blurred through the lens. It's not uncommon practice for professional photogs to do that.
this guy knows what actually happens, PP, tons of PP I watched her videos on how she processed thoses photos, lots of layers, levels, background replacement... no camera can shoot that even with a god lens.
06-25-2016, 10:23 PM   #43
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Looks like some video tutorials found at K1 productions :-)
https://www.youtube.com/channel/UC37YX_5sEWTk024SPAXWG3Q
06-26-2016, 06:17 AM   #44
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QuoteOriginally posted by biz-engineer Quote
Looks like some video tutorials found at K1 productions :-)
https://www.youtube.com/channel/UC37YX_5sEWTk024SPAXWG3Q
Looks interesting but it is not about the K-1. They are PP tutorials.
06-26-2016, 06:55 PM   #45
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There are common shooting scenarios where there are lenses available for apsc and lenses available for FF. Both do fine used with skill.

What is interesting is seeing lenses that didn't seem right on apsc turn into jewels on FF. The 43mm for example. The 31 on apsc is exquisite, on FF it is a totally different beast, alot wider still with the exquisite rendering. Something who mastered it on the apsc has a challenge to master it on FF.

Either end, short or long have advantages on each format. Wide and fast becomes complicated on apsc, with limited choice whereas FF is a simpler proposition. Long apsc is preferable; the 300mm is a long portrait lens on FF.

What I'm interested in is another extreme, low light. I like the 70 mm macro on apsc for flowers, a nice mixture of width and magnification. On a FF, I suspect a 90 or 100 mm will give me the same satisfaction. But what really attracts me, both for long and macro is a couple of stops or more low light performance. I'm not interested in razor thin dof, but being able to stop down to get a deeper dof without losing detail from noise. 3200 ISO is the new 800 Iso, which definitely would get me shots I couldn't otherwise.

Of course if Pentax released an apsc with a stop or better noise performance that would change the equation considerably.

Last edited by derekkite; 06-26-2016 at 07:01 PM.
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