Canon 7D vs Mark IV Noise levels when cropping is required
I have been using the Canon 7D for a few months now doing mainly bird photography with it. At first, I was a bit taken back by the higher-than-expected noise levels but eventually realized that noise levels were similar to the 5D Mark II when photographing birds from a set distance. In other words, the 5D Mark II images had to be more heavily cropped than the 7D due to sensor dimensions (1.6x vs full frame) when photographing birds from a set distance and the 7D outresolved the 5DM2 with about the same level of noise.
Since most of us, most of the time are unable to walk up to a bird I am wondering if the extra cropping required by the Mark IV will negate the benefits of lower noise levels.
Your thoughts?
Thanks,
Alan
Let me explain further...
Here's my point...
The 5D Mark II is touted as a low-noise camera...which it is when you can fill the frame with the subject your are photographing...portrait photography, etc.
In my test, I have taken images from both the 5D Mark II and 7D from a set distance using the same lens at ISO 1600 for a test. The subject (text on a box) takes up about 1/6 of the frame on the 7D while the 5DM2 takes up only about 1/10 of the frame. (Similar to what you might expect when photographing a perched bird from a distance.)
Once both images were loaded into Photoshop, I cropped each image to 300 ppi so that the box with the text fills the frame by about 1/3rd in both cases.
The 5DM2 image shows slightly less noise with lower resolution when compared to the 7D...they are very close however.
(If you care to look at the examples, you can view the images here. They were both converted from RAW w/o any noise reduction:
7D:
http://www.iwishicouldfly.com/iwishi...ped_300ppi.jpg
5DM2:
http://www.iwishicouldfly.com/iwishi...ped_300ppi.jpg
My point is that the 1.3x sensors and full frame sensors require greater cropping of the subject in order to create a properly cropped print. In doing so, noise is amplified and this somewhat negates the "lower noise" touted in 1.3x and full-frame sensors. That is why I am wondering if the Mark IV will truly perform any better (noise-wise) than the 7D when photographing from a set distance to a subject. My guess is that it will, but only by a small margin.
Again, this only applies to situations in which your are focal-length limited...in other words you must shoot from a set distance from your subject.
Alan
For Clark and others...feathers it is...
Same test but with feathers:
5DM2:
http://www.iwishicouldfly.com/iwishi...pi_feather.jpg
7D:
http://www.iwishicouldfly.com/iwishi...pi_feather.jpg
In the previous test, I did let ACR auto adjust exposure. This time nothing has been altered except color noise reduction setting of 25 for both images.
Both images were taken with the Canon 600mm f/4 IS lens at a set distance of 30'.
I suspect the 1DM4 will have slightly better resolution than the 5DM2, but not as good as the 7D. I'm sure the noise level will be lower however and how much of a role it plays towards overall image quality will be the key.
Canon has done such an excellent job with the 7D's autofocus and fps, the advantage of the 1DM4 will boil down to its noise level capability. So far from what I have seen on the net, it is quite good, but from a bird photographer's viewpoint where in many instances we are cropping our shots, how much better will it be? The more you crop an image, the more noticeable the noise level becomes. A 1.3x sensor will require a heavier crop than a 1.6x sensor.
For those of you who have the 1DM4 on order, it would be great to do some comparison cropping between the 1DM4 and the 7D and post them here!
Alan
Here are comparison samples between the 7D and Mark IV @ set distances.
Browsing Flickr.com I found comparison photographs between the 7D and Mark IV at various ISO's taken from the same distance (w/o noise reduction applied).
Cropping the photographs to the exact same frame reveals that the 7D has more detail but with more noise. By applying NR to the 7D cropped image to equal similar noise levels of the Mark IV, I get about the same level of detail.
This is by no means conclusive and frankly I'm getting tired of seeing just night/dark images taken with the Mark IV at ridiculously high ISO's!
Here are the links to the comparison images:
-- 7D:
http://www.flickr.com/photos/hirokik...439495/detail/
-- 1D Mark IV:
http://www.flickr.com/photos/hirokik...437379/detail/
Special thanks to Hiroki in Japan for these images.
Cheers,
Alan