black frame test

[gerald_matar]

<p>i heard that a black frame test is good.<br>

so i would like to know how to perform a black frame test and where should i post the results for review?</p>

<p>thank you</p>

<p> </p>

[KenPapai]

<p>Use a Lens Cap, put your camera in manual, 1/30 at f/16 and shoot an image at each ISO.</p>

[15sunrises]

<p>I'm not quite sure what this test is supposed to prove, all cameras will demonstrate some noise at certain ISOs. Taking a picture of the inside of a lens cap is still one of the strangest things I've heard of. Why not go out and take pictures of what you actually shoot and see if you're pleased with the performance? Apologies in advance if you exclusively shoot unlit caves with no artificial lighting.</p>

[mike_sinquefield]

<p>Exactly Dave. The proof is in the pudding...If you're happy with the real world results, just go out and take pics. Why waste shutter actuations on the back of a lens cap...</p>

[hal_b]

<p>I disagree. I am a photographer of a specific niche that frequently explores dark places and aims to shoot dark imagery. I usually try to underexpose by at least 6 stops, to make sure I can't see any detail. I then enlarge my prints to wall-size and show them in abstract galleries. The idea is that you can just imagine what it would have been like to be in that dark place. That's what I call my exhibit: "Imagine how dark it was". Any noise in my photographs will distract from the darkness. I've experimented with black paint, and just painting the wall black, but I find that it lacks that "photographic" realism that really brings you back to the black ness.</p>

[JDMvW]

<p>Hal, I quite agree. The easiest way to get there is to open the image in Photoshop. Set the background color to black and then select the entire image and hit the delete button. The purest black you'll every see, and not a single distracting detail, except for that pesky random noise from the viewer's eyes (<a href="http://dspace.dial.pipex.com/town/avenue/pd49/pockets/weird/entoptic/entop/entoptic.htm">entoptic</a> images).</p>

[hal_b]

<p>I tried closing my eyes once, just to see how dark it could get. That random entoptic noise (thanks for the word; I never knew what it was called) ruined it for me, though. I've found that the truest blackness has to be experienced with eyes open.</p>

 

<blockquote>

<p>Set the background color to black and then select the entire image and hit the delete button.</p>

</blockquote>

<p>An interesting suggestion. I will try this next time I am dissatisfied with my results (shouldn't take me long, as I am frequently dissatisfied). With the introduction of more expensive cameras, I have gladly parted ways with my money in search of High-ISO blackness. The theory is that...well, I don't know the theory. I was never good at math. But I strive for black darkness at ISO 25600 at the very least. I am excited at the prospect of creating dark pictures with the newest cameras that will record at ISO 102400. This should add a whole new dimension to the darkness.</p>

[KenPapai]

<p>I also refer you to Hal's premise on IQ here:</p>

<p><a href="http://www.photo.net/casual-conversations-forum/00UnvO">http://www.photo.net/casual-conversations-forum/00UnvO</a></p>

<p>Bravo!</p>

[hal_b]

<p>Yeah, today seemed like a big day for the peepers. Lots of conversation about alot of relevent new issues that have never really been resolved for me...like <a href="../canon-eos-digital-camera-forum/00UnZ4">ISO noise</a>, <a href="../canon-eos-digital-camera-forum/00UntW">quality</a> and <a href="../beginner-photography-questions-forum/00Umk8">disappointment</a>.</p>

[KenPapai]

<p>Rob and Hal -- so bravely patient posting answers in the<strong><em> Beginners </em></strong>forum. Bravo again. ;-)</p>

<p>I don't know how you do it.</p>

[keith reeder]

<blockquote>

<p>i heard that a black frame test is good.</p>

</blockquote>

<p>And you'll have heard that from someone who thinks that all that matters about a camera is to thrash contrived, irrelevant "images" (such as black frame test files) to within an inch of their lives in conversion/post processing in order to provoke some <em>utterly-irrelevant-in-the-real-world</em> IQ issue so that they can then spend the next six months bitching about it.</p>

<p>Seriously - the only <em>worthwhile</em> test for your 7D is this:</p>

<p><strong>Take a <em>load</em> of pictures.</strong></p>

[tim_klimowicz]

<p>Having owned a 30D that has serious noise banding issues that begin at ISO 400 and get progressively worse the higher you go (or the more you push in post), I definitely have no problems with this sort of test. I like shooting a lot of low-light, and I don't mind noise at all. What I *don't* like is when my images look like they were shot with a crappy mobile phone camera because there's ugly horizontal bands of noise in the shadows.</p>

<p>All of the 7D pictures I've seen until now seem to lack this banding noise, but you're damned right this will be one of the first things I test when mine finally arrives tomorrow.</p>

[keith reeder]

<blockquote>

<p>All of the 7D pictures I've seen until now seem to lack this banding noise</p>

</blockquote>

<p>Then why in God's name:</p>

<blockquote>

<p>but you're damned right this will be one of the first things I test when mine finally arrives tomorrow.</p>

</blockquote>

<p>If you can see a problem <em>in an image,</em> it's a problem - in which case a black frame test is pointless and irrelevant: and if it can't be seen in real world pictures, why in God's name torture yourself by <em>actively looking for</em> issues in a way that has no bearing whatsoever on real world photography?</p>

<p>Incidentally, it's exactly this kind of "torture chamber" testing that has resulted in several "testing experts" jumping onto DPR, Fredmiranda, Naturescapes, Luminous Landscape forum, Photography On The Net and just about every other Canon photography forum you care to name, to declare - as loudly and as often as possible - that the 7D <em>has the worst banding of any APS-C camera yet.</em></p>

<p>This is despite the fact that - as you yourself admit - the <em>images</em> we see from the 7D are almost invariably as clean as a whistle, and that in fact the first 7D characteristic that many of us acknowledged and appreciated was that it seems to have deal comprehensively with banding/pattern noise.</p>

<p>The result of their efforts is that there is now an appreciable subset of the 7D owner community who are fretting and worrying about this "issue", <em>even though they aren't seeing it in their own pictures.</em> <br /> <br /> <strong>It's utter bloody madness.</strong></p>

<p>I own a 40D and two 30Ds and I can make their files look <em>terrible</em> if I thrash 'em in PP and look for problems - I can generate banding, excessive noise, you name it: but <em>in use</em> , all three cameras are great - I frequently use my 40D at 1600 ISO and above.</p>

<p>I will be having a 7D, and I<em> couldn't care less</em> about what it might do in a black frame test, because I know that unless it's a faulty body - in which case I'll know from the images - it'll be superb.</p>

<p>Black frame test results can tell you a lot, <em>but they mean nothing.</em><br>

<strong><br /> </strong></p>

[15sunrises]

<blockquote>

 

<p>Having owned a 30D that has serious noise banding issues that begin at ISO 400 and get progressively worse the higher you go (or the more you push in post), I definitely have no problems with this sort of test. I like shooting a lot of low-light, and I don't mind noise at all. What I *don't* like is when my images look like they were shot with a crappy mobile phone camera because there's ugly horizontal bands of noise in the shadows.<br>

All of the 7D pictures I've seen until now seem to lack this banding noise, but you're damned right this will be one of the first things I test when mine finally arrives tomorrow.</p>

 

 

</blockquote>

<p>The 30D only has 'serious noise banding issues' if the image is improperly exposed. You can create noise at ISO100 by underexposing and pushing in post, just get it right in camera and you won't have to deal with the banding issue. If you have noise in the shadows after post, it's because you didn't expose for the shadows, the 7D won't magically fix the mistakes a photographer makes.</p>

[keith reeder]

<p>Man!</p>

<p>I could have saved myself a lot of typing by just saying what Dave T said!</p>

<p>;0)</p>

[mbkissel]

<p>Bravo, Keith! I've been reading some of those other forums, and the incessant IQ thrashing/bashing is just hilarious to me now. Some of those folks need to get off their duffs and go shoot some photos. </p>

<p>I really like my 7D. I think it's the best APS-C camera available; for certain the best that I've owned. It produces beautiful images at 1600, even 3200 ISO for my needs. It's a whole lot of camera, with a different set of features, and I'm still learning it's ways. The new focus system just rocks!</p>

[keith reeder]

<p>I just don't understand this "assume the worst" mindset, Mark - I buy gear <em>and start with the expectation that it will be fine. </em></p>

<p>Looking for problems while still learning the gear is the most perverse thing to do, and the worst time to do it.</p>

<p>This whole thing is like someone saying "<em>I'm picking up my new car tomorrow, and the first thing I'll do is drive it into a tree at 70 mph to make sure the airbags work...</em> "</p>

<p><em>You </em> <em>just don't,</em> do you? You assume things will work as they're supposed to.</p>

<p>But where cameras are concerned this odd, pessimistic, "<em>assume the worst and then look for it</em> " perspective seems to be be coming more and more pervasive, and it's just nuts.</p>

<p><strong>What a joyless existence some of these people must live if they're only happy when they've found things to complain about, and spend all their waking hours looking for them...</strong></p>

[mbkissel]

<p>Amen, brother! Couldn't say it any better.</p>

<p>Keith, I know you are considering the 7D from some of your postings. All I can say is get one. It is a spectacular camera. And if/when you do get one, don't throw it down on the pavement to check the airbags.</p>

<p>I really can't see how any <strong>intelligent</strong> person, whether or not you buy Canon, Nikon, Pentax, Sony...etc., could not like this camera. Just because I drive a Ford doesn't mean I disdain Ferrari. I'm just glad to see Canon keep raising the bar.</p>

[keith reeder]

<p>Oh, the only thing that's stopping me from having a 7D in my hand right now is that I've decided to fund it by selling off some older, unused gear - and things are a bit slow on that front.</p>

<p>But I've no doubt whatsoever that it'll be an exceptional tool for my "enthusiast" bird photography efforts.</p>

[JDMvW]

<p>I frequently shoot at ISO 3200. It's not that I <em>mean</em> to do so, but I forget to dial back the ISO button after I use the top speed. Where'd I put that damn lens cap?<br>

But then, I shot old High-Speed Ektachrome and GAF 500 slide film back in the mid seventies......</p>