I appreciate your detailed post and description of test comparison example. I ask your help in “dumbing” this down so that I may understand in practical terms of what it does for me.

We have a wall space for a 24x36 inch print. We decided something wild life would be interesting. Presently physical limitations force me to shoot from my vehicle, but I know of a pond in nature center. Upon arriving at the parking lot, I spot a colorful duck sitting on a rock, but it’s far away. By putting a 400mm lens on my 90d (a 33 megapixel ‘Crop’ camera) I can frame a shot where top of the ducks head is at the top-edge, the beak tip on the left edge, the end of the tail feather on the right edge, the waterline at the bottom edge. (I know this is not a good composition but please ignore for now). I drive home, put the card in the printer and create a 24-36 print. The print shows a lot of feather details, looks good, friends admire it and we are happy. I read your post, and wanting to show my best work, I dutifully drive to th store and buy a(31 megapixel’Full’ frame) 5d4. Upon returning home I mount the same 400 mm lens drive to the pond, park in the exact same spot, the very same duck is in the exact same position on the same rock. I look through the viewfinder and the duck and rock appear much smaller and nothing’s near an edge so I exactly center them and take the shot using the same settings. At home, I put the card in the computer, and crop so everything touches the four sides again and print another 24-36 print. Why will this print look better on the wall? This is why many of us talk about ‘reach’, it enables us to get us the images we desire. Yes there are hypotheticals in this analogy, but it’s the best way I can make my point. If someone can can show that you will get a better result in this situation. I’ll buy one and I’ll stand corrected.

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Dear Click.... and others on this thread... ...

I am exhausted in 'trying to enlighten' others on this subject.. I have put the 'information out there, it is up to each and everyone of you to decide what you wish to do with it.......... Do you own homework

.... With the 'Wealth' of the internet out there.. I leave the 'continued education' on this subject to each of you to do on your on and for each you to find and live by your own decisions.

I would close by quoting... “Knowledge is wealth, wisdom is treasure, understanding is riches, and ignorance is poverty.”…
. Quote by: Matshona Dhliwayo...

With that said,,, each of you on this thread must decide for yourself if you wish to pursue 'Wealth, Treasure, Riches, OR... Some other direction in your life. I will ‘leave each of you’ to choose the path which best fits your needs… The decision is yours, and decisions have consequenses... I know what works for me.

Cheers
GeoVz
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Thank you for replying, but I feel you avoided the issue of useful ‘effective reach’ which is the universally expressed advantage of a crop sensor. In your example you mention a target, what did you use and what size was it, did it have fine detail?

What if you had done the experiment, with the same cameras but, moved the tripod back by a factor of 1.6 and then completed the process with both cameras and then compared equal size 12x18 or 24x36 inch prints? Now just for the hell of it, consider replacing the 7d2 w/ a 90d an do again. Are you sure you can still brag about the quality of the resultant prints?

For many of us, this is real life. Please help us understand, explain without the self expressed platitudes of your ‘knowledge’ and ‘wisdom’.

You may be right, but please teach us our errors with meaningful, practical, real life examples.

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Paul.... I will make one more attempt to help you understand where you are confused. If this does not work, we will still be friends... and I will remain silent… I truly wish to help you understand..... But, it is OK if we have different views.

The following statement is a direct quote from the introduction of Internet 'Wiki' entitled “Crop Factor” and I will post the link below... it says...

....." Of course, the actual focal length of a photographic lens is fixed by its optical construction, and does not change with the format of the sensor that is put behind it....."

The same "Wiki" also says...

..... " Because of this crop, the effective field of view (FOV) is reduced by a factor proportional to the ratio between the smaller sensor size and the 35 mm film format (reference) size. ...."

So Paul, what a photographer is doing -- is taking a 'smaller piece' of the 'FOV' and stretching it to what a FF camera would be... therefor creating an illusion or MYTH.... Read the below URL link.

https://en.wikipedia.org/wiki/Crop_factor#Introduction

I might also add that, by using a smaller sensor, and ‘stretching’ the actual ‘captured’ smaller image, you have now introduced much more ‘noise’ into the resulting, enlarged rendition…. If you were to shoot the picture with a full frame sensor… you will have the exact image in the center of that full frame… AND, this will be on a ‘better quality sensor with less noise’ ….

Simply put Paul, the photographer is ‘capturing a smaller piece’ of the FOV, stretching it, and by doing so, ‘reducing the quality’ of the partial capture… and you are doing this on a sensor of ‘lesser quality..’

But, your basic argument is that, if someone take a 300 mm lens, from a FF (24mm x36mm -FF) sensor camera, and they put it onto a APS-C (22.3mm x 14.9mm) or 1.6 crop sensor camera.. you now have a 480 mm lens………….

Now, my question to you is…... If that is such a wonderful idea? Why stop there…. Let’s put the same 300mm lens onto a Micro 4/3 sensor (which is 18mm x 13.5m) which has a crop factor of 2.0 and now…. You have a 600mm lens…. WOW!!!..... OR…. Your using a 300m which cost $ 5,000 and replacing a 600 mm lens which cost about $ 12,000… What you have done is created a negative equivalent size equal to that of the old 110 cameras… and saved one heck of a bunch of money…. NO, it does not work that way Paul

Camera companies make smaller sensors because they can reduce their cost, there is less the difficulty of manufacturing the smaller sensor, and they can provide a cheaper product to the consumer…. It is a given fact that Full-Frame sensors can cost as much as 10 to 20 times the cost of a APS-C sensor… Camera companies do NOT make smaller sensors to help photographers think that they have a ‘BETTER’ system for a cheaper price………… There is NO logic in that…

So, basically, your theory is …. Reduce the size of the sensor, that make the size of the lens bigger, and bigger, and you still get this wonderful and glorious, beautify picture… and OH, BTW, the cost just keeps going down.?? How does that work?

I would invite you to read the article from B & H, which is one of the most trusted camera stores out there and it is entitled…. “Understanding Crop Factor” … the link is below…

https://www.bhphotovideo.com/explora/photography/tips-and-solutions/understanding-crop-factor

In the sixth paragraph of this article it says… and I quote …. “However, regardless of what kind of camera or sensor you place behind the lens, the focal length will not change just because you have a larger or smaller sensor or frame of film…. “

Next, continue to read, down to the section entitled “Crop Factor” and you will see that what you are doing is, in fact, just ‘capturing a small’ piece or area of the FOV, then through what is known as Post Processing, you are ‘Stretching’ this ‘small capture’ and making it bigger…. Therein lies the the ‘false illusion’ …

I would like to point out to you that “if you shoot in the Full-Frame to begin with” …. You still have the same image in the center, only with more canvas or sensor area around it….

I would also point out to you that this is what camera manufacturers actually make what Canon calls the “S” lens… which means ‘smaller’ sensor… and they are made at a cheaper price and cover only the small sensor, and not the FF sensor… and even with this “S” lenses, the lens is NOT designated as a 480mm lens when it is actually a 300mm lens. Everyone thinks it is “480mm” because, again, you ‘stretch’ the image …. Put a different way… ‘Stretching an image does NOT make you lens bigger…or longer…’

So Paul, in the wise words of the Canadian based Philosopher, Matshona Dhliwayo, who is known for this quote …. “Knowledge is wealth, wisdom is treasure, understanding is riches, and ignorance is poverty.”… I will ‘leave you’ to choose the path which best fits your needs…

Cheers
GeoVz
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