Previous page Next page

ISO Sensitivity / Noise levels

ISO equivalence on a digital camera is the ability to increase the sensitivity of the sensor. This works by turning up the "volume" (gain) on the sensor's signal amplifiers (remember the sensor is an analogue device). By amplifying the signal you also amplify the noise which becomes more visible at higher ISO's. Many modern cameras also employ noise reduction and / or sharpness reduction at higher sensitivities.

To measure noise levels we take a sequence of images of a GretagMacBeth ColorChecker chart (controlled artificial daylight lighting). The exposure is matched to the ISO (i.e. ISO 200, 1/200 sec for consistency of exposure between cameras). The image sequence is run through our own proprietary noise measurement tool (version 1.6 in this review). Click here for more information. Room temperature is approximately 22°C (~72°F), simulated daylight lighting.

Canon EOS 7D vs. Canon EOS 50D vs. Nikon D300s vs. Pentax K-7

  • Canon EOS 7D: Canon 50 mm F1.4 lens, Aperture Priority, Manual WB,
    Default Parameters (Standard PS), High ISO NR Default (Standard), JPEG Large / Fine
     
  • Canon EOS 50D: Canon 50 mm F1.4 lens, Aperture Priority, Manual WB,
    Default Parameters (Standard PS), High ISO NR Default (Standard), JPEG Large / Fine
     
  • Nikon D300S: Nikkor 50 mm F1.4 G lens, Manual Exposure, Manual WB,
    Default Parameters (Normal), High ISO NR (Normal), JPEG Large / Fine

  • Pentax K-7: Pentax 50 mm F1.4 lens, Manual Exposure, Manual WB,
    Default Parameters (Bright), High ISO NR default (Medium), JPEG Large / Premium
  Canon EOS 7D Canon EOS 50D Nikon D300S Pentax K-7
ISO 100
ISO 200
ISO 400
ISO 800
ISO 1600
ISO 3200
ISO 6400
ISO 12800    

Up to ISO 800 the differences between the competitors are pretty marginal. The only camera that is visibly noisier than the rest is the Pentax K-7. As we go up the sensitivity scale the gap between the Pentax and the others widens even more but the two Canons and the Nikon D300S stay pretty close. As usual the Nikon maintains a very good balance between noise and image detail up to the highest sensitivities. The EOS 50D's approach to noise reduction is more heavy-handed and results in more blurring of fine detail than on the Nikon. Despite its higher nominal resolution and therefore smaller pixel-pitch, the EOS 7D produces a marginally cleaner image than its sister model at higher ISOs, but crucially also manages to retain some more image detail.

All in all the EOS 7D is, considering its impressively high resolution for an APS-C camera, doing a very decent job. On a pixel level it shows comparable amounts of both luminance and chroma noise to its most direct competitor, the Nikon D300S, but its higher nominal resolution will give it an advantage when printing or displaying an image on a screen. Images taken with the two very high test ISO settings are not always pretty to look at. However, the two 'Hi' settings are there in case you need them and the output is certainly usable at smaller sizes.

Noise graphs

The graphs below pretty much confirm what we have seen in the sample crops above. In numerical terms the two Canons and the Nikon are pretty much on the same level up to the very highest sensitivities where the EOS 7D has a measurable and visible advantage over the 50D. The Pentax K-7 is by far the worst performer at higher ISOs in this comparison.

  Canon EOS 7D
Chroma
Black
Gray
Indicated ISO sensitivity is on the horizontal axis of this graph, standard deviation of luminosity on the vertical axis.

RAW noise

Finally let's take a look a the EOS 7D's RAW output next to the competition. Removing any in-camera noise reduction and processing the images using Adobe Camera Raw (V5.6 Beta in this case, all NR set to 0) gives us the nearest thing to a 'level playing field' for assessing the relative noise levels of the four cameras' sensors.

With noise reduction turned off we get a more accurate idea of how noisy these sensors are and the image looks slightly different to what we've seen above in the JPEG section of this page. The Pentax K-7 is much closer to the pack but it also becomes clear that the 7D produces a cleaner image than the 50D and, at very high ISOs, also than the D300S. This explains to a degree the 50D's slightly softer JPEG output at high ISOs. Its JPEG engine has to apply more chroma noise reduction than on the 7D in order to get noise onto the same level.

  Canon EOS 7D RAW Canon EOS 50D RAW Nikon D300S RAW Pentax K-7 RAW
ISO 100
ISO 200
ISO 400
ISO 800
ISO 1600
ISO 3200
ISO 6400
ISO 12800    

Raw Noise graphs

Again, the graphs below confirm what we can see in the sample crops. The 50D produces more chroma noise than the EOS 7D at higher ISOs. The Pentax K-7 is still slightly worse than the Nikon and EOS 7D at very high ISOs but the gap is smaller in RAW. At high ISOs the the 7D and its closest rival, the Nikon D300S, are more or less level in terms of chroma noise.

  Canon EOS 7D
Chroma
Black
Gray
Indicated ISO sensitivity is on the horizontal axis of this graph, standard deviation of luminosity on the vertical axis.
Previous page Next page
1720
I own it
184
I want it
322
I had it
Discuss in the forums

Comments

Total comments: 10
Girish Madpuwar
By Girish Madpuwar (3 weeks ago)

I am 7D user and have noticed that my images are considerably soft. I mostly use canon 100-400L lens. Initially I thought that its problem with the way I use camera. I tried all possible things. Searched lot and found many discussion about AF problem with 7D. Can someone share their experience?
It seems 7D AF is not consistent although manual focus gives considerably crisp and sharp image.

Comment edited 45 seconds after posting
0 upvotes
Patcheye
By Patcheye (2 months ago)

I'm a wheelchair user and have gone for the 7D because of the increase in range when using a shorter lens over full frame which means though I often cannot get close I often achieve a useable image.

Live on the coast so to avoid problems re dust on the sensor from the beach I purchased a second one a few months back which says, I think, just how pleased I am with the product. Re low iso and noise, possibly because of high light levels from sea reflection and living in a flat open area I personally find no problems but using 2.8 lenses helps. Not professional but have had people use my stuff on their websites - so for my needs the 7D works well - Oh, and if like me you have poor dexterity you'll find the raised buttons really helpful even when wearing gloves.

Comment edited 1 minute after posting
0 upvotes
Ajaykdelhi
By Ajaykdelhi (2 months ago)

I have a 70D, am getting a used 7D at $ 800 next week, will provide a comprehensive review after that

0 upvotes
TahoeJohn
By TahoeJohn (2 months ago)

My Review of the Canon 7d as the owner of one for 1yr is this.I shoot Professionally and have used the 7d for just about 1yr.It is a bit bigger,heavier than my other EOS Canon's.Picture quality is top of the line.Video quality is top of the line.The Grain Factor when using the ISO at a higher number is compensated by a setting in the Menu so no problem.At 8fps continuous it stands above the others.Weather proof as well (Body only).Recently my Canon 7d was knocked over while mounted atop a 6ft tripod landing on solid asphalt.A little scratch on the body was all the damage it received.Though bigger and heavier the construction,function,image quality of this Camera is incredible.I shoot Landscape,Portrait,sports(MMA Fights) and everything in between.Canon went above and beyond with this model.A+ is the grade I give for this one.

0 upvotes
Shashank90
By Shashank90 (3 months ago)

Which one is a better model 70d or 7d , I have read numerous reviews and seen plenty of videos, even though 70d is a much newer version I would like to know from some one who has used them side by side.

0 upvotes
Jostian
By Jostian (2 months ago)

I think both are great, depends on your needs, the 7D is like a tank, the build quality is incredible, its AF is phenomenal (a cut above the 70D in terms of customization options), the 70D has slight advantage 2/3 of a stop at higher iso's, has wifi and touchscreen, the 7D has bigger and better OVF, and the 70D have awesome video capabilities. I played with both and went for the 7D (easy choice), the 70D felt like a toy and I didnt like the plasticky feel (compared to the 7D). Bit both are great, you'll enjoy either depending on your needs.

0 upvotes
EhXsan
By EhXsan (4 months ago)

what is max usable ISO on canon 7d?

1 upvote
PhotobyCarlos
By PhotobyCarlos (7 months ago)

www.photobycarlos.com all my pictures with 7d

2 upvotes
DreamRunnerPhotography
By DreamRunnerPhotography (3 months ago)

Checked your photos at photobycarlos.com. Really it was awesome :) Finally I decided to go for 7D after saw your website. Tnx !!!
please suggest me some good lenses which are more better for portrait & landscape shooting

0 upvotes
gjpuk
By gjpuk (1 month ago)

For potraits i use 5omm prime canon 1.8mm
for landscapes a sigma 10-20mm

0 upvotes
Total comments: 10