[Ian Stuart Forsyth]

The camera used for the test by Photozone.de are both apcs. The results of the test are obvious: the pixel density of a 10 mpx camera is inferior to that of the 16 mpx camera.

Not arguing this

That's math. Obviously , given the same composition with both the cameras and given the same lens on both, you'll find more detail with the 16 mpx camera.

Not arguing this

I repeat: given the mpx count, given a composition, pixels are just pixels, on FF and APSC

For pixels that are 2 times smaller that lens needs to resolve more to record the same level of resolution as a pixel that is 2 times larger.
If you take a look at the Fullframe or APS-C for sports or bird photography - Page 3 - PentaxForums.com
you will see as the 10 mp gets smaller they can only record less and for the same 10Mp count with larger photosites the record more detail
so for 10 mp image from the K10 it can deliver more line LW/PH with those 10 mp, and if we compare 10 mp cropped from the k5 I will resolve less LW/PH as shown above.

Its a good thing that you bring in a LP filter most of the time we see as pixels counts go up the strength of the filter goes down. Even with this we see a decrease with how much detail a 10mp crop from the K5 can capture when compared to 10 mp form the K10.
Why is this important be cause the discussion was about cropping for reach, but with larger photosites you do not need to adjust the focal length of the lens to equal the same FOV. Most of the time you can get away with only having to increase the FL around half of the crop factor to achieve the same level of detail need for a highly cropped image in wildlife photography.

Let’s have a look at the 35 F/2.5 if we had a camera that used the same pixel density as the K10d but increased the size of the sensor such that it would be equal to 16mp only increasing the size of that sensor by a factor 1.26 ( half the area different between FF and cropped) What would we get ?

That camera using those pixels the size of the K10d would deliver 2955 LW/PH

And the look at what decreasing the pixel size by a factor of 1.26 get you 2679 LW/PH

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Last edited by Ian Stuart Forsyth; 05-22-2017 at 03:03 PM.

[normhead]

This is not your brightest retort, normhead.

This is ridiculous. You're basing your whole point by limiting the definition of reach to the ability of the lens. Effectively, reach can also refer to magnification at the same distance. What we mean by reach is that using a 24 MP FF camera and a 24 MP APS-c camera, the APS-c camera will give you more magnification, and therefore more apparent reach. The point is compared to a 450mm lens on FF, you can get the same image using a 300mm lens on the APS-c. SO interns of IQ, images size etc. 300mm APS_c gives you the same "reach" as 450 FF. Since each is hardly a scientific term I fail to see how this would be a misuse of the the terminology. However I can see how claiming an APS-c camera and FF camera have the same reach with the same lens, might be a logical argument for film era cameras, in digital it's just misleading.

What exactly is your problem with defining reach in this way?

If it were an exact scientific term I could see it, but you're getting semantical about the vernacular, and that's just silly. The vernacular changes faster than you can blink.

---------- Post added 05-22-17 at 06:50 PM ----------

For pixels that are 2 times smaller that lens needs to resolve more to record the same level of resolution as a pixel that is 2 times larger.

Any good quality lens does resolve more than needed for an APS-c sensor, that's why you can increase your subject resolution with a 1.4 of 1.7 TC. There's that much untapped resolution in any DA* lens, Limited or comparable lens... . The point that is escaping you is that it's not a matter of need, it's a matter of many lenses already doing that.

The fact that many use high resolution lenses that out resolve their sensors by a huge degree, means with smaller pixels you are using the resolution of the lens more efficiently. Using too large a pixel as in many 18-24 FF action cameras, the extra resolution of FF lenses is simply wasted due to the large pixel sites.

---------- Post added 05-22-17 at 07:03 PM ----------

The camera used for the test by Photozone.de are both apcs. The results of the test are obvious: the pixel density of a 10 mpx camera is inferior to that of the 16 mpx camera. That's math. Obviously , given the same composition with both the cameras and given the same lens on both, you'll find more detail with the 16 mpx camera. That's OBVIOUS : more pixel can resolve more detail, given the same composition. It's like a mosaic: the smaller the pieces, the more the detail you can achieve. I repeat: given the mpx count, given a composition, pixels are just pixels, on FF and APSC . A mosaic of 24 000 000 of pieces is simply that. differences in detail can be visible due to other causes: lack of LP filter, for example, or a different image processing by the camera engine.

When you downsample images to a lower resolution, the effect is that of a sharpening just at low magnification, but actually you loose high magnification possibility. All depends on the magnification of the output device.

Don't be disappointed if Ian doesn't get this, I've been trying to get through to him for years. it's just not in his mindset.

[galelegg]

Thanks to all for replies you have given me plenty of info to consider. When I return home I will examine these photo's on my desktop, currently on mobile phone as I write this post. From my phone that brings me to another consideration regarding my photography. A pro photographer at my club said for you Ron (my name) ask yourself where will your photos will end up. If you want to make money then you will need the best equipment, its tough game and from posts many of you are making money from photography. For me 20 photos a year in amateur competitions and sports photos on clubs Facebook pages most likely viewed on a mobile phone by the players etc. The club pro said in your current situation don't be to concerned about high quality equipment. Those that view your photos will not know the difference. Its a mobile phone world even she said I'm using my mobile phone for photography more and more.

[clackers]

Despite of what you think of the contrary, I am pretty sure I know what I am talking about.

The OP ask: "Fullframe or APS-C for sports or bird photography". In this context "reach" started to find its way into the discussion.

You advanced this all embracing answer:

Quote "I'd stick with crop, Galegg. You're basically making your lenses get fifty percent more reach" End of quote.

In my book the "reach" of a lens is determined by its focal length. And that never changes.

Now I'm positive you don't know what you're talking about, SS.

If you continue to deny this, just put the 300mm on your crop camera, put to your eye, then full frame, and put to your eye.

I'm talking about reach, the only one around here banging on about 'But a focal length never changes!' is you, champ.

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Last edited by clackers; 05-22-2017 at 09:26 PM.

[Dan Rentea]

Tough subject this one with "the reach".
Even if the focal length is the same on both camera, one being a full frame and one a crop camera, the crop camera will give you a different perspective due to the crop factor (1.5x on Nikon/Pentax crop cameras and 1.6x on Canon crop cameras). Clark's suggestion is very good. I'll tell you the conclusion if you don't have a full frame and a crop camera to take the test. Shooting with a crop camera and with a full frame camera the same subject, from the same distance and with the same lens, the subject in the image taken with a crop camera will look 1.5x or 1.6x closer.

[Schraubstock]

put the 300mm on your crop camera, put to your eye, then full frame, and put to your eye.

In your example above the view changes not the focal length of the lens.

The physical focal length of a lens never changes unless you re-design the lens.

Have a look at this it may help you to understand. Advance to 03.50 if you impatient.

Crop vs. Full Frame Cameras | SLR Lounge

By the way, this will be the last post on this topic I will submit.

Cheers

[Dan Rentea]

In your example above the view changes not the focal length of the lens.

The physical focal length of a lens never changes unless you re-design the lens.

Have a look at this it may help you to understand. Advance to 03.50 if you impatient.

Crop vs. Full Frame Cameras | SLR Lounge

By the way, this will be the last post on this topic I will submit.

Cheers

This is true. The physical focal lenght never changes. Only the angle of view due to the crop factor.

[bm75]

No one said that FL changes. There's a misunderstanding about the word "reach" of the lens. We all would refer to "What we see in OVF" than "reach" . and with APSC we see the 1,5x crop of the FF composed image

[normhead]

No one said that FL changes. There's a misunderstanding about the word "reach" of the lens. We all would refer to "What we see in OVF" than "reach" . and with APSC we see the 1,5x crop of the FF composed image

Exactly, no ne ever said the FL changes, we said "More reach". More effective enlargement, narrower FoV, all the things "reach means when you aren't using your lens with two different systems. As soon as you use different size sensors with the same lens, and MP, the smaller sensor gives you more reach. FL has nothing to do with it.

If you are shooting one of the many FF action cameras that are less than 24 MP, the "reach" factor become even more exaggerated.

[bm75]

The misunderstanding with the word appears when you consider the distance to the subject. Some are arguing that distance from the subject doesn't change from FF to APSC (that's obvius..that's a property of the lens, no matter the crop of the sensor) thus claiming there's no more "reach" . If I've undestood right, those people consider reach as a synonim of distance/ subject magnification ratio. In fact they claim FF+ 400\600 mm is better because, with those lenses, you stay away from the subject , possibly obtaining quite the same composition in the OVF but with the full resolution of the FF. For me , instead , reach is just what I see in the OVF, no matter the distance because I just need to fill the frame...so yes, for me I have more "reach" with APSC, given a FL.

[normhead]

From my days shooting....
Same, lens, same FL(250mm DA*60-250) , Pentax K-1, K-3 and Q
What would be the logic for saying they all have the same reach?

K-1


K-3


Q-S!

[RonHendriks1966]

From my days shooting....
Same, lens, same FL(250mm DA*60-250) , Pentax K-1, K-3 and Q
What would be the logic for saying they all have the same reach?

With the birds, the Q is a winner.

[clackers]

In your example above the view changes not the focal length of the lens.

Who said it does?

I think the Equivalence Fanatics are superficial on most matters and downright wrong on others, but they are right at least on this telephoto aspect.

You can multiply by the crop factor to show that to fill the frame with the same deer or fox you can do with a 300mm on APS-C, you're going to need 450mm on full frame.

I'm speaking as someone who does shoot action and wildlife, not just a watcher of YouTube videos.

[hrutii]

You should ignore the crop factor and compare across cameras instead. Like others have said, the 36mp FF sensor of the K1 cropped will give you similar (if not better) results to the K3 sensor, uncropped. So if that is the only deciding factor then it's not really one at all.

I think you should also consider weight too though. What type of birding do you do? For trips of 5-6 hours of non-stop birding I've found a lighter setup helps a lot for handholding. If you're more of a tripod guy, then that doesn't matter much.

[clackers]

You should ignore the crop factor and compare across cameras instead. Like others have said, the 36mp FF sensor of the K1 cropped will give you similar (if not better) results to the K3 sensor, uncropped. .

The K-3 will give you 24Mp, the K-1 15Mp.