imagemeister Loc: mid east Florida

Arthur Morris has all the full frame cameras and big prime lenses he wants - and yes, that is where TC's work BEST - plus, of course, he KNOWS how to use them ! Some day, when he gets tired of carrying the big lenses and tripods, he may TRY pixel enlargement with smaller lenses and crop frame bodies and not look back ........

DaveO Loc: Northeast CT

Figured you knew what you were doing,but maybe the nikon TC is constructed differently. If not,oh well.....I gave my 55-300 to a family member along with a D7000 and 18-55. My wife got my D7100 and 18-140 and the rest is mine,but I do share with her!

Steve Perry Loc: Sylvania, Ohio

Unless I misunderstood, I thought we were just talking about a single body cropped vs that same body with a TC. In that case, I still think the TC is better than just cropping. Although I'm intrigued by up-rezzing the cropped file, I'm still not overly optimistic (unless you have poor glass with a poor TC).

For a crop camera vs full frame with a TC, it's a different story and I agree 100%. Assuming the crop camera is higher pixel density than the full frame camera, it's an easy win for the crop camera every time. With my D5, if I need a "TC" I use my D500 instead! I did an article / video on that topic too :)

http://backcountrygallery.com/comparison-test-crop-camera-vs-1-4x-teleconverter-full-frame/

imagemeister Loc: mid east Florida

Yes, this exemplifies some the points I have been trying to make ! Speaking strictly to optical resolution, cropping on high pixel density wins - BUT, there is a point where ISO/noise begins to over ride the pixel density advantage in lower light levels and the full frame lower noise level begins to look better.

imagemeister Loc: mid east Florida

That is why I used the Canon 300 2.8 and TC 2XII in my testing ! The subject was a Red bellied Woodpecker ........not printed text .....

Steve Perry Loc: Sylvania, Ohio

I'm not sure if you're talking about cropping an full frame, crop camera or what. However, when comparing a higher pixel density crop camera to a full frame camera with a TC you have keep in mind that full frame camera loses its ISO advantage over the crop camera since the TC ate a stop of light. In Nikon, the full frame bodies only have about a 1 stop advantage over the D500 (the D5 has 1.5). This scales up the ISO scale. So, full frame + TC vs crop camera = the same noise levels even when the ISO climbs. Now, if you start cropping the crop camera the story changes, but you would presumably have to crop the full frame camera + TC for the same shot (more actually since it's 1.4 instead of 1.5 crop), so it's a wash.

Steve Perry Loc: Sylvania, Ohio

The reason I test with printed text is because it's fixed. I control the entire situation. If you're testing with woodpeckers, you're not really testing anything. Here's my test method:

http://backcountrygallery.com/lens-sharpness-testing/

It takes all of the variables out and allows me to test in a very controlled way. If you're using PDAF with TCs on woodpeckers, there's too much variance to come to any conclusion beyond just an anecdote.

imagemeister Loc: mid east Florida

No, I am leaving TC's out of this mix entirely - just talking about cropping on FF vs APSC.......


Here is another image, for the bird people, 1.7X CIZ, Sony A77II, Sigma 100-300 from tripod.

(Download)

imagemeister Loc: mid east Florida

There is something to be said FOR real world field testing also ....though.

Steve Perry Loc: Sylvania, Ohio

I agree to a point, but the problem with "real world" testing is that there are too many variables in play. When testing something - like is a camera sharper when you crop or when you use a TC - you need to eliminate everything but the teleconverter in that equation. Basic scientific method.

For example, if you're out testing this in the field, there are tons of variables at play. For one, the PDAF system always has some variance so it might focus better on one shot than the next. The AF sensors really aren't boxes, and if more of the AF sensor is on the focus point in the first shot than the second, there can be variance there. If you're not using single point AF, then there's a chance the camera is picking a different AF point than what you think. If the sun is out, it can introduce mild atmospheric distortion that can cause diffraction between you and the subject to varying amounts. This can also affect the PDAF system and fool the AF sensors into thinking they have a lock when they don't. There's also the variable of handling the camera. If you're touching the camera, you're introducing motion and it's impossible to repeat the exact same motion from shot to shot. If you're hand-holding it's even worse. On top of that you're shooting a subject that's moving around. Plus, if you're comparing a TC shot to a non-TC cropped shot and hand holding (or have the setup loose on a tripod), then the TC rig is harder to steady than the non-TC rig, possibly introducing more movement into the TC shot.

And those are just a few variables off the top of my head. However, if just one of those variables comes into play, it can skew the results, making you draw conclusions that simply aren't accurate. Maybe you moved a little on the TC shot and when you compared it to the crop where you didn't move, the crop seemed better. Not saying that happened, just giving an example.

So, that's why I like controlled tests. I like to eliminate all of those variables so I'm actually testing just one single variable. I don't mind then taking that out to the field and making sure what I saw in my tests is accurate, and if it's not trying to figure out why, but I wouldn't trust any uncontrolled test.

Just my opinion, we don't have to agree :)