Background Noise with 7D

[zvia_shever]

<p>I went to my local camera store today to take some test shots to compare the new 7D with my 30D before making the decision to drop $1,700. I've heard some good and bad things about the 7D and I wasn't sure what to believe. <br>

First I took some indoor, low light shots at ISO 1600, the 7D definitely beat out the 30D. Then I went outside and took a couple shots at ISO 100. On my computer screen at home, I liked the overall result of the 7D shots better especially after a little tweeking in Elements (I shot in Raw). I liked the fact that I could use more sharpening without ruining the edges of buildings/signs/words etc...probably due to the higher megapixel count. I found just one problem though....even at ISO 100, the beautiful blue sky in the background had this weird noise throughout, much worse than my 30D. I was able to get rid of most of the sky noise using a noiseware plug-in...but it still thought it was weird. Anyone else have this issue? Is this perhaps due to the 18 megapixels? Will this show in print? Any other suggestions regarding upgrading from the 30D if in fact this is a common problem with the 7D?<br>

BTW....I shot in RAW in Program mode using the exact same lens, plus I compared 100% crops on the 7D shots to 156% crop on the 30D to try and compare apples to apples so to speak. <br>

Thanks, Zvia</p>

[PuppyDigs]

<p>I don't have any problems with sky noise at ISO 100-800. At ISO1600-3200 you have to really exposure to the right and use NR. Whatever, 7D noise control is a lot better than my 50D but not as good as my 5DII. Realize the RAW converter makes a lot of difference in the interpretation of the file. I've gotten the cleanest RAW to TIFF files from Aperture 3, followed by DPP and ACR trailing. The JPEGs straight from the camera are amazing. You can get similar NR by converting in DPP at defaults. I think for LR and ACR you need to use a plugin and manually apply NR. They have NR but it's not very good. NR in Aperture 3 is surprisingly excellent--much better than Aperture 2--but not as tunable as a dedicated plugin like NeatImage.</p>

<p>Much of the noise you see on screen while pixel peeping doesn't actually show even in fairly large prints.</p>

<p>7D/15-85/ISO100 (processed in Aperture)<br /> <img src="http://emedia.leeward.hawaii.edu/frary/flora_fauna_images/flowers_0576.jpg" alt="" width="601" height="400" /><br /> 7D/15-85/ISO3200 (wee bit 'o blue sky/(processed in Aperture))<br /> <img src="http://emedia.leeward.hawaii.edu/frary/downtown_images/Downtown_Xmas_0246.jpg" alt="" width="600" height="902" /></p>

[zvia_shever]

<p>Hi Puppy face....how do I add a couple of images to show you what I mean?</p>

[zvia_shever]

<p>Just tried to load a sample but something is wrong with the server. Anyhow, I was using ACR but plan on buying Aperture 3 tomorrow. I was holding off on Aperture until 3 came out. How is the conversion from raw to jpeg in Aperture 3? If necessary I'll get a NR plug in for Aperture also. Another question....in Aperture 3 (or a plug in available for Ap3), can you selectively reduce noise? <br>

Most of the prints I make are not huge (12x18 is the biggest). I mostly shoot on trips/vacations (4-5 trips a year) and my family and make photo books using the best pics....so it's a big deal for me to spend $1,700 on a new camera when I really don't "need" one. But it's been almost 4 years since my 30D and I'm ready for an upgrade. </p>

[PuppyDigs]

<p>You need to upload them to a hosting service or website and link them to your post (click on the little tree icon and enter web address).</p>

<p>I've not owned a 30D, but I used a 20D for 2 years and it is almost the same as the 30D (same CMOS). The 7D generally handles noise much better, especially at ISO 800-3200. But the 7D is more demanding of accurate exposure (doesn't tolerate underexposure as well).</p>

<p>Of course you can make any camera image look noisy by underexposing and bumping up the exposure in post production. 18MP 7D files are huge compared to the 8MP 30D files. A 13x19 print from the 7D will require much less rezzing up (enlargement) than the 30D, so any 7D artifacts you may view while pixel peeping will be far less apparent in the actual print. Why? At pixel level you're viewing a smaller more magnified image area than pixel peeping on the 30D. So even if the 30D is a little cleaner at pixel level, the extra uprezzing will reveal more artifacts.</p>

<p>There were a lot discussions at FM about 7D noise and much of it dissipated when better RAW converters were finally released.</p>

<p>Of course it is possible you tried a defective 7D or were subject to RFI.</p>

[g dan mitchell]

<p>Keep in mind that when you view your 7D at 100% magnification you are looking at a much smaller portion of the overall frame than with your older camera.</p>

[zvia_shever]

<p>Puppy...what's RFI?<br>

G Dan.....when I compared the photos, I did take that into consideration. I looked at the 7D shots at 100% and the 30D shots at 156%...somewhat comparable I guess. I'll try to post the images.</p><div></div>

[zvia_shever]

<p>Will try to post 7D now</p>

[zvia_shever]

<p>7D image...hopefully</p><div></div>

[keith reeder]

<p>ACR isn't <em>at all </em> a good converter for the 7D - NR won't help much, because the conversion algorithms in ACR produce this blotchiness, and NR really can't deal with it.</p>

<p>"RFI" is Radio Frequency Interference. Don't worry about that.</p>

<p>For now, why not try a few conversions in DPP? I don't use it myself (I prefer Capture One 5) but DPP will generate <em>much</em> "cleaner" conversions than ACR.</p>

[zvia_shever]

<p>Thanks Keith....I am heading out in the morning to buy Aperture 3 and will try their converter. Will also try DPP, although I'll have to find the disk that came with my 30D....do you know where I can get the latest updated DPP? I'm just not comfortable buying the 7D until I can get a clean image.</p>

[PuppyDigs]

<blockquote>

<p>"RFI" is Radio Frequency Interference. Don't worry about that.</p>

</blockquote>

<p>I get herringbone artifacts when shooting near UFOs, radio transmitting towers and during sunspot cycle peaks. Dad burn freaky. I thought ET was calling me home.</p>

[keith reeder]

<p>Oh yeah, I'm not saying it's never a problem - but one step at a time.</p>

<p>Zvia,</p>

<p>you should have the latest DPP on the disc that came with your 7D, otherwise you'll have to navigate to it via this page: http://www.usa.canon.com/consumer/controller?act=DownloadIndexAct - but note that you'll need an old version on your machine for the "updater" to update.</p>

<p> </p>

[zvia_shever]

<p>Haven't bought the 7D yet, so don't have the disc. I'm about to head out to get the disk from my brother's 40D and then will upgrade from the canon site.....I think the 3.7.3 is the latest. Will report back :)</p>

[michael_young3]

<blockquote>

<p>I looked at the 7D shots at 100% and the 30D shots at 156%...somewhat comparable I guess.</p>

</blockquote>

<p>Pixel count relates to area, which has a squared relationship to image dimensions. Downsample the 7D image by 80% to see how it compares to images taken at 11.5 MP. Going the other way, upsampling the smaller image by 125% (sqrt(1.56)), doesn't have the same effect.</p>