5dsr & cropping

[gary samples]

I have a few math questions mixed in with some theory
I shoot 600/f4 200/f2
and some with the canon extender III @ 200- 600- 840
with the 5dsr what type of reach can I expect
cropping in and still have 20- 24 raw files I know lens resolution needs to be factored in there also.
thanks guys for any insight !

 

[rs]

When cropped to 1.6x, you get 19.6 MP. At 1.3x, you get 30.5 MP. Multiply your focal lengths by this to get your equivalent framing.

 

[gary samples]

thanks
200mm with a 1.6 x = 320mm
200mm with 1.4 III extender and 1.6x = 512mm
600mm with a 1.6x = 960
600mm with 1.4III extender and 1.6X = 1344mm and still have 19.6 mp
any info on the resolving power of these lens

 

[Eldar]

I believe it will be a lot of guessing at this point, since we don´t have any images to judge or measurements to check. But regarding resolution and resolving power, putting one of those lenses on a 7DII would give you a good hint. Those two lenses are also close to the best you can get, so I would think 1.3x and 1.6x cropping would work like a dream, provided you don´t push ISO too much.

 

[takesome1]

Theory and framing questions aside.

My 7D II gives me between a 15 - 20% edge over a comparable cropped picture out of the FF. 12' from subject vs 10' with FF. I tested this using my 500mm F/4 II

I am hoping for the same out of the 5Dsr. That little bit of edge without the crop body negatives when you can frame appropriately will be nice.

 

[privatebydesign]

Theory and framing questions aside.

My 7D II gives me between a 15 - 20% edge over a comparable cropped picture out of the FF. 12' from subject vs 10' with FF. I tested this using my 500mm F/4 II

I am hoping for the same out of the 5Dsr. That little bit of edge without the crop body negatives when you can frame appropriately will be nice.

Can we see the tests and can you tell us the test conditions? And how do you measure/conclude "15-20% edge"?

 

[takesome1]

Theory and framing questions aside.

My 7D II gives me between a 15 - 20% edge over a comparable cropped picture out of the FF. 12' from subject vs 10' with FF. I tested this using my 500mm F/4 II

I am hoping for the same out of the 5Dsr. That little bit of edge without the crop body negatives when you can frame appropriately will be nice.

Can we see the tests and can you tell us the test conditions? And how do you measure/conclude "15-20% edge"?

If you are really interested in seeing tests samples, yes. It will not be today because I am not at home.

The tests were in a controlled setting, controlled lighting with all the normal steps to control vibration. Focused in live view and manual mode. I used an ISO chart I printed off line.

What I was trying to establish for my own use is how much benefit did a 7D II actually gives.

I used a 5D II as my FF, and set it as the control camera. If my memory is correct I started at 15' for the FF. I then shot with the crop camera at 1.1x the distance from the target as the FF camera. I carried this out 1.2x, 1.3x ...on to...1.6x

For the comparison I knew that if I shot and cropped a bird photo with both bodies I would crop the exact same field of view and print or display the exact same media size. To simulate this I cropped the center target out of the ISO chart for the same fov. I then resized the files to the exact same size.

My conclusion was drawn comparing the cropped center target pictures against each other and determining at what point the crop pictures degraded below that of the FF. At 1.2x the crop and ff are very similar. At 1.6x the crop files are far worse than the FF.

 

[StudentOfLight]

thanks
200mm with a 1.6 x = 320mm
200mm with 1.4 III extender and 1.6x = 512mm
600mm with a 1.6x = 960
600mm with 1.4III extender and 1.6X = 1344mm and still have 19.6 mp
any info on the resolving power of these lens

Your best estimate is by looking at TDP crops for the 7D mark-II which has roughly the same pixel pitch as the 5Ds. The 5Ds-R will probably look a tad sharper...

Here are crops of the 600mm f/4 IS II on the 7D-II "bare" vs "with 1.4xTC":
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=748&Camera=963&Sample=0&FLI=0&API=0&LensComp=748&CameraComp=963&SampleComp=0&FLIComp=1&APIComp=0

The 200 f/2 has not yet been tested with a 1.4xTC on the 7D-II.

 

[Ebrahim Saadawi]

Don't confuse yourself. It will be just like shooting with an APS-C 1.6/1.5x DSLR in terms of final image. (especially identical to the 7D mk II)

A 50mm lens gives the FOV of about an 80 on APS-C
A 200mm gives the FOV of about 300mm on APS-C.

Just multiply by the crop factor available on the 5Ds (1.6 and 1.3) and you'll get the field of view and depth of field equivalent to FF.