[beholder3]

I have no idea what a APSC NEX speedbooster is but I have owned several full frame and crop sensor camera bodies and I can say without any reservation that the characteristics of a lens changes when you put it on a full frame vs a crop sensor. Here is another way to look at it. Take a picture on a full frame camera. Now take the same lens and put it on a crop sensor body. Compose the exact picture you just took on the full frame (you will need to back up a little). You will see the DOF changed and the picture looks different.

A Speed booster is a wide angle converter (optics), just as there are teleconverters.
And using one you effectively turn an A50mm/1.2 FF lens into an 36mm F0.85 lens with the investment of $150 or so (but only works with smaller register distance --> NEX). Not only do you get the exact same DoF and blur and noise characteristics (the total amount of light is primarily defined by the optical system not the sensor), but even the resolution goes up (obviously pixelcount is still a bottleneck).
https://www.lensrentals.com/blog/2013/01/metabones-magic/
Sidenote: The above also busts the myth that there is no fast enough glass "for APSC" to compete 1:1 with FF.

You attitude seems to suggest that you have never owned a full frame body because I have never seen somebody switch to full frame and then feel like they needed to go back to crop (with the one exception shooting wildlife).

Surely I only have limited experience, but I think owning both a K-1 and 5D3 with some appropriate glass should give me at least limited insights into what looks I can create how.

Some while ago I asked my friend Kermit to help me out comparing the visual impact of sensor sizes and focal lengths and apertures keeping the subject frame the same:



I am not saying FF has not reason to exist. I just say that most of talk about it is myth and over-simplistic (thus wrong) statements from both photographic and physics standpoints.

[normhead]

Just curious, did you get a model release?
I've always wanted to work with Kermit, you lucky guy.

[phat_bog]

I am not saying FF has not reason to exist. I just say that most of talk about it is myth and over-simplistic (thus wrong) statements from both photographic and physics standpoints.

Bringing Kermit over here to validate this wasn't necessary but sure it's cool

Both your photographic and physics standpoints are irrefutable, and of course everything else is myth considering technology today.

That said , things would only different in the film world, comparing an APS-C sized film & 35mm, of more, or 35mm or 6x4,5 with photographic chambers. Mostly because of chemical/physical specs of the photographic support.

Honestly i still use aps-c a lot today, even if i use FF everyday.
I used digital APS-C for years combined with medium format, and no FF for years.
What did i use most? APS-c. Why? because of the equipement size.
What do i use most today? FF. Why? the equipement size again, large prints possible with broader shooting capabilities than medium format.
And why do i still use APS-C? equipement size again. a little fuji with a little lens goes unnoticed and delivers great pictures with lovely sizes to process rapidly.

I hope one day Pentax will develop a similar to Fuji Xpro, aps-c camera, as it will surely become my everyday camera.

[biz-engineer]

I am not saying FF has not reason to exist. I just say that most of talk about it is myth and over-simplistic (thus wrong) statements from both photographic and physics standpoints.

Most comments here are regarding background blur. As already written in several posts, the background can be completely blurred, for example, take a 400mm lens @ f5.6 framed on a small bird, and here you go, background is smoothly blurred. No need of FF , APSC does it very well. This kind on composition (small bird or small Kermit), has nothing artistic, those are all "technical" shots, the lens blur the background and the subject is sharp, ok, 99% of the posts are referring to this, this can be done with micro4/3 when getting very close to a subject and having a background very far away from the subject. In the Kermit example, there is a flat background, it is not a background with progressive distance. Now, consider photographing real size people models (1.75m high) having their feet on the ground (in that case, the background can't be miles away). FF framing + fast lens give that 3D effect, much harder to reproduce with APSC. Do you understand what I mean, or, in your analysis, do you stay at the level of a "technical" blur?

[redcat]

x-post, a blur background for free, I don't need more blur than that (but I don't mind a K1 for free either )

[beholder3]

This kind on composition (small bird or small Kermit), has nothing artistic,

The Kermit framing is the size of a human head and shoulder portrait shot- it is a rather large Kermit. You'll learn that this is not really an unusual scenario where photographers use and care for and compare blur and it is not macro.

I'll let any readers here judge if they agree with you that the size of the photographed object increases the level of "artistic" quality. Makes it really hard to take you serious.

give that 3D effect

Maybe the earth is flat and was created by a spaghetti monster 2000 years ago. If we want to discuss purely technical physical differences (sensor size is physical area not a bit more), then fairy dust and fantasy and personal liking are off topic.
I have not read a single forum user ever who was referring to "3d effect" in a discussion about comparing sensor sizes and had even remotely understood the basics of imagetaking.
It is these myths and fluffy undefined attributes which people tend to evade to when there are no arguments left.
Next we get the "FF look" and Elvis lives on the backside of the moon.

, much harder to reproduce with APSC. Do you understand what I mean,

Sadly this is easy to understand nonsense. Only in the narrow cases for DSLRs and equivalent exposure settings which you can not reproduce (requires the fastest possible lenses on FF and not nothing short of wide open and must ignore mirrorless cameras) a smaller format it get's "harder". That is in not even "5%" of possible cases.

Remember the APSC NEX with the wide angle converter: It will create 100% the same images from a blur perspective. This inevitably falsifies any statement that "APSC" can't produce those images, because it does.

If you just focus on specific cherry picking scenarios then we all can find dozens of those where one format trumps the other. The usualy failure in argumentation is that people cherry pick extreme scenarios and then repeat them in an over generalized way.

I have already said that there is some benefit in FF DSLR cameras. But it is not much.

I do own and shoot the Canon 85/1.2L on a Canon FF for a reason. But I could put it on the APSC NEX + speedbooster as well and get the same shots. It's is just much more inconvenient. And people need to differentiate between "more inconvenient" and "not possible".
This thread is titled "can't do without". From a non-technical perspective there is not a single image you could not do on the APSC NEX, because all definitve differences are either convenience or autofocus or other purely technical parameters.

[Barry Pearson]

If you just focus on specific cherry picking scenarios then we all can find dozens of those where one format trumps the other. The usualy failure in argumentation is that people cherry pick extreme scenarios and then repeat them in an over generalized way.

I agree. That is why I post about my own experiences, rather than attempt to generalise to what other people would experience.

And my own experience is that the K-1 is significantly superior to the K-3II in nearly all respects. I find it easier to use, I get a higher percentage of keepers, and typically they are better keepers. I mainly shoot action, such as motorsports and airshows, but I also shoot the occasional landscape, and do studio work.

As a result, my K-3II is now relegated to a back-up camera in case my K-1 breaks.

(I used at least 6 models of Pentax full frame film SLRs from 1967 to 2004. I used 6 Pentax flagship APS-C digital SLRs from 2004 to 2016. Now I've switched comprehensively over to the Pentax full frame digital SLR, and I'm scrutinising my APS-C equipment to decide what place it has in my future).

I certainly won't claim that (say) most other people would have the same experience! (Although I am aware of some who do). And, of course, it would be wrong of someone who is successful with APS-C, (and there are vast numbers of such people), to assume that there aren't significant numbers of people, (but almost certainly a minority), who wouldn't benefit in similar ways by moving to FF.

[Kerrowdown]

If you have a shed load of old FF K mount lenses, then clearly the K1 is heaven sent

That'll be me then...

[biz-engineer]

I have not read a single forum user ever who was referring to "3d effect" in a discussion about comparing sensor sizes and had even remotely understood the basics of imagetaking. It is these myths and fluffy undefined attributes which people tend to evade to when there are no arguments left.

After 25 years of photography, I still don't understand the basics of image making, I still have a lot to learn :-). Since I swallow marketing propaganda, I acquired a K1.

Should I resell the K1 system?

[noelpolar]

Elvis lives on the backside of the moon.

Whilst unlikely, he did gain quite some weight in his later years suggesting he was preparing to move to a cooler climate.

And before one dismisses it off hand completely, Pentax did release a FF digital camera.

[micromacro]

Hm... I don't understand this thread. Lisa Holloway is an amazing pro, but all her pictures are edited in Photoshop, one way, or another. It is possible to get dreamy editing with any camera, more or less.
Here are useful tips from her:
https://iso.500px.com/backlight-natural-light-portrait-photo-tutorial/

[Barry Pearson]

After 25 years of photography, I still don't understand the basics of image making, I still have a lot to learn :-). Since I swallow marketing propaganda, I acquired a K1.

Should I resell the K1 system?

Or you could start a thread "What can you do with an APS-C camera that you can't do without?"

After all, it isn't the case that APS-C dSLRs are the "proper" ones, and FF dSLRs need to be justified in some way. They are now both equally valid options that don't need to be justified to users of the other range.

(Only 25 years? I bought my first 35mm camera 53 years before buying the K-1. I was at school at the time).

[beholder3]

After 25 years of photography, I still don't understand the basics of image making, I still have a lot to learn

Many users have progressed farther in their understanding after less than a year. Trying harder would probably help.

[monochrome]

Has anyone asked yet what you can do with {anything else} that you can't do with K-1?

[bertwert]

Has anyone asked yet what you can do with {anything else} that you can't do with K-1?

Take photos underwater without a case... or in a volcano... pretty much nothing else...