Canon 7D Noise-Compression artifacts

[Stock-Photos]

<p>Hi,<br /> Got my new 7D today from B&H. I'm posting a 100% crop image which shows horrible noise/compression artifacts, ISO 400. I shot large jpg in fine mode. A follow on posting will show the exif.</p>

<p>Is this the image quality I should expect? It's much worse than my 10D and 5D.</p><div></div>

[Stock-Photos]

<p>Exif</p><div></div>

[enrique_bocanegra]

<p>turn auto light optimizer off-disable. There is your problem.</p>

[bobatkins]

<p>Auto lighting optimizer makes very little difference.</p>

<p>Compare it side by side with the 10D and 5D shooting the same subject under the same lighting at the same ISO setting, preferably using prints, or at least at the same image scale on a monitor screen. Then decide which is better.</p>

[michael_young3]

<p>There's a handy rule of thumb for exposing for the moon, Lunar-11, somewhat like Sunny-16 for bright daylight: f/11 at 1/(ISO) seconds. This shot was underexposed by 1 stop (f/10, 1/1000, ISO 400), maybe more if you shot it through a window. There's a bit of stippling that didn't clean up with noise reduction. That and the overall low contrast led me to wonder if this was shot a through a window. But I don't see ghosting from the secondary reflection in the glass, so that maybe wasn't the case.</p>

<p>For what it's worth, more light makes for less noise. If the situation allows, lower ISO is a better choice. Underexposure is always bad; it's better to err slightly on the side of overexposure if it can't be right on. RAW will allow better recovery of details, and as in this shot, allow a more appropriate selection of Picture Style after the fact. Landscape picture style boosts the blues and greens, more appropriate for daylight pictures of leafy things. Lastly, if you decide to shoot RAW in the future, definitely turn off ALO and highlight priority. These settings skew the histogram, while giving back nothing useful in return, since you would post process it manually anyway.</p>

<p>I know you must be writing because this shot is disappointing. I shoot a 7D also, and get good prints at ISO 3200, for appropriate scenes. Noise is inevitable at low light levels, and removing it kills detail. It helps to have the "right" expectation, so you can account for it while planning the shot. That will come in time. Shoot something tomorrow in less challenging light, and put on the happy face for a while.</p>

 

[philip_wilson]

<p>The 7D does tend to suffer from noise more than my 5DII. At first I assumed thatthe camera was completely at fault but with practice I learn't a few things. Firstly it is best in RAW and the DPP engine was the best conversion - I have just gone to ACR 5.6 and will see how that works. Secondly the 7D is very sensitive to underexposure - especially at high ISO which makes the images quite noisy. Thirdly for shots where you expect to have noise issues always shoot RAW - the 7D is much better in RAW than in JPEG. I will post some very small crops taken from hockey shots to show noise from the 5DII, 7D and 1dIIN at high ISO. All of the crops are about the same area of the shot and show the 7D is not really that bad.</p><div></div>

[philip_wilson]

<p>Looks ugly but is due to underexposure - here is what the 7D can do</p><div></div>

[philip_wilson]

<p>Now here is the 1DIIN at ISO 3200 - similar area of a shot - as you can see it is a lot worse than the 7D.</p><div></div>

[philip_wilson]

<p>Finally you can see how good the 5DII is at ISo 3200. While it looks like this shot was taken closer it is actually the same area of a picture as the other two images. The 7D crop is 454x286 pixels from a 5184x3486 pixel image so it is 0.725% of the full shot, the 1DIIN is 314x205 pixels from a 3504x2336 image which is 0.786% and the 5DII is 549x291 pixels from 5616x3744 or 0.76%. Obviously in this post the i,ages will be a different size as they contain a different number of pixels but in a print they will all be the same size. Based on my display (the size will vary depending on the display) you are essentially looking at ISO 3200 performance on a 60 inch x 40 inch print. Even at this size you could make a good poster from the 7D at ISO 3200 (obviously not fine art!).</p><div></div>

[KenPapai]

<p>Then 7D has a nice tight spot metering mode. Your photo is evaluative (makes no sense that AE mode for the moon).</p>

<p>First thing I said when I opened your too large inline image (it's over 700 px) is "underexposed, thus noise will be seen).</p>

<p>The 7D is pretty excellent at ISO 1600 and usable indeed at 3200. I assume the moon photo is just an example but ISO 200 at 1/500 f/5.6 would be fine and virtually noise free.</p>

[felix_mizioznikov]

<p>make sharpness 0<br>

also make sure it's turned of on your computer. Also try shooting raw </p>

[philip_wilson]

<p>Ken - the 7D is my first APS-C body and it is much more sensitive to noise at high ISo when under exposed than the 5DII or 1DIIN as you can see from the Hockey short crops I posted. Is this sensitivity a feature of all APS-C bodies or is it unique to the 7D?<br>

I agree with you that the OP's shot has something else going on. It looks like some combination of underexposure and post processing. There may other things going on with the shot. If you look at the EXIF it was taken in very bright light (ISO400, F10 and 1/1000) almost EV 15 which is very bright conditions for shooting the moon.</p>

 

[Stock-Photos]

<p>Phil, no post-processing at all. I changed some settings since that shot and I'm getting smoother results now, but still below my expectations. I'll post another better 100% crop and the exif on Sunday.</p>

[philip_wilson]

<p>Try shooting RAW and using DPP to convert hopefully my hockey shorts crops show that you can get reasonable results even at high ISO with the 7D. When I first bought the 7D I was disappointed with it's high ISO performance but after a while you get to know it's perculiarities. The other thing that takes care is the metering system. If you are a long time EOS user you will have got used to the way the Evaluative metering system behaves and how much exposure compensation to add. Because the new metering system takes into account the subject colour it is different to the other EOS bodies. You still need exposure compensation but usually quite a lot less than you would normally use - typically the 7D is 2/3 of a stop closer to the correct exposure than other EOS bodies. It is possibly this fact that has caused some of your exposure issues. Unless you have a problem with your copy you should get very good results at ISO 400. If you look on this forum when the 7D first launched (Beginning of October 2009) you will find a few people disappointed with the 7D at high ISO. After a while you should find that the results are great up to ISO 800 and that they are very usable at ISO 1600. I find the 5DII clearly superior even at ISo 100 but for the price the 7D delivers great results.</p>

[philip_wilson]

<p>I forgot to mention - have a look at the histogram the 7D meter takes a while to get used too and you saw my comment about how it is sensitive to underexposure. That said your image does look especially bad. While I have not owned the 10D I would expect the 7D to be much better (as you can see mine is as good as the 1dIIN at high ISO and has the benefit of more pixels). It's high ISo performance should be very close to the 5D if you have the exposure correct.</p>

[john_a_odermatt]

<p>I noticed the date shot was in year 2000! What gives?</p>

[Stock-Photos]

<p>John A, camera was new. I had not set the date yet.</p>