Sensor Cleaning Time

Uh-Oh! I just noticed this dark blob showing up on my pictures. I've really cropped it tight and enhanced it, but it's there in the shots if you know where to look. I've had this 7D for 6 months now, and I've got a whole gaggle of lenses that I sometimes swap on and off a lot, so I'm not surprised. I'll have to try and give it a good cleaning before I go back to the airshow tomorrow. I'm just glad I caught it now before I've shot thousands of pictures this way.  I've gotten 34,768 pictures with this camera since buying it right before Thanksgiving last year, and I've only scratched the surface on what it can do.

Two Nights In A Row

I was going to do a series of moon shots for you, but since it's cloudy and raining outside tonight, I guess my number of days in a row is going to end at two. So here are two shots of the waxing moon, one from Friday night and the other from Saturday. Pretty cool, eh? The Saturday shot is a little overexposed compared to the Friday shot. I didn't have as much time to play with it and try a bunch of different settings on the camera, but I think both of them are more than acceptable. The magnification on these is huge, with a 400mm lens, a 2x teleconverter and a 1.4x teleconverter, plus the 1.6x crop factor of an EF-S sensor, for a total of 1344mm! That's a lot of zoom.

I know that stacking teleconverters is a no-no, leading to lots of image degradation, but until I get much longer and better lenses, I'm pretty happy with these shots.

Up In The Airfest 2010-Part 9

Here's a little piece of advice. Always look at the pictures you're shooting. Somehow, the strap on my camera twisted the little mode dial from aperture priority to full manual, and I didn't notice for almost 100 pictures. So I've got a whole series of shots that came out like this. Twice, actually. It happened later in the afternoon, but only for a few seconds because I was paying more attention.

What you're not seeing here is an acrobatic performance by John Black and his Super Decathlon. Nothing too exciting if you've seen this sort of thing before. I'm not too torn up that I didn't get any pictures of it, actually, but I hate the thought that I might have missed something important.

I'm thinking it's a design flaw in my 7D that allows the camera strap to accidentally rotate the mode dial. I don't remember that ever happening on my XSi or the old XT. It's something I'm certainly going to have to watch more closely. I wonder if there's a different way to attach the strap...

Zoom Zoom Zoom Zoom

I've always said you can never have too much zoom lens on your camera. Problem is, the more zoom you have, the harder it is to get a quality picture. Here's a little example I shot this evening with an old lens I had and a couple of new fancy Canon Extenders I found at the pawn shop for a good price. Unlike the cheap 400mm lens, these extenders are top of the line. They'll find a place in my camera bag while I wait to be able to afford a nice long prime lens. Anyhow, the shot above is from one end of my living room to the other with just the big 400mm zoom telephoto lens. With the 1.6x crop factor of my 7D, that makes this shot about 640mm. At that kind of zoom, I can't come close to hand-holding it, so I've got it on a tripod and I'm triggering the shot with a remote. I guess I should learn how to lock the mirror up and take the shot, but I'm not quite there yet. Take a close look at the Justin Wilson LP just right of center.

Here's the next shot with a 1.4x extender thrown into the mix. Notice that in addition to giving more zoom, it's also darker. The 35mm equivalent zoom here is 896mm. That's pretty big. This is also the last exposure that the camera would autofocus on and really didn't think it would, but it did. All the remaining shots are manual focus. See that Justin Wilson LP? Not the one left of center in this shot but the other one, still to the right of center. Look close and you're beginning to see a lot of Chromatic Aberration. That means the different colors of light are traveling differently through the lens, and they aren't coming together quite right on the image sensor.

And here's a shot with the 2x Extender in place, making a 1280mm shot. Way, way, way long, and way too dark. I think I shot this one at a full stop more than the camera wanted, and I still had to brighten it up a little. Look close at our Justin Wilson title and you can see it's getting a lot worse. This is in pretty poor lighting, so maybe it wouldn't be so bad in daylight, but it still wouldn't get you into National Geographic.

Last but not least, this is the 400mm lens plus the 2x extender plus the 1.4x extender plus the 1.6x crop factor, making for a total 35mm equivalent of 1344mm! That's a lot of zoom! However, this is clearly the worst picture of the lot. It's almost to the point where you can't read the lettering on the Justin Wilson LP. If you were a double naught spy, though, this would certainly get you some incriminating photographs. Now, if I only had a nice 400mm L series f/2.8 prime lens to try this little test on...

So what happens when I put all these together? The collage above shows all the pictures crammed into one, with the lens alone at the bottom, followed by 1.4x, then 2x, then 1.4x and 2x on the top. I blew up each picture by the same factor as the missing extenders to get the scale the same in each shot. I also tried to fudge the levels a bit to get the brightness levels the same, but I didn't go crazy with it. (You can see where the camera shifted slightly between shots, I must need a heavier tripod.) Anyhow, you can see that I'm probably just as well off zooming the photo digitally as I am by having all that extra glass. I think if I had started with better glass, there would be fewer flaws to amplify, but it would still be a trade-off. I have a lot to learn when it comes to such things. Maybe I should just go back to a point-and-shoot with a 10x zoom and quit worrying about such things. Sure would be cheaper.

The New Camera, The Old Tree

OK, I did it. I ordered a new camera. After my Rebel XSi broke at the shuttle launch, I knew I needed to get something. Something bigger, better and in my hands. Fixing my camera is going to cost a few hundred dollars, but more urgently, it's going to take six weeks or so. With the holidays well inside that six week window, I couldn't wait. So I ordered a brand spanking new Canon 7D. This is the top of the line crop sensor camera from Canon, and they don't come much better than this. I just got in via UPS on Wednesday, and today was my first chance to take it outside and put it through it's paces. I have to carry the instruction manual around with it, because I don't know how to do many of the things I want to do yet, and with so many buttons, wheels and even a little joystick, it's hard to find things at a glance. I've still got my rented 100-400mm lens from the shuttle launch, and combined with this 18 megapixel sensor, I got some great picture of small birds from far away. You've seen the old tree behind my parent's house many times before, and I've probably brought you pictures of this very same kestrel before, but never this clear. I've cropped all of these picture down to almost 1:1, so click on them and see just how well this camera/lens combination works.

That old tree is home to not only the kestrel at top, but also this woodpecker and an occasional buzzard.


I didn't catch this hawk actually in the tree, but he did fly past in a big hurry. I managed to get this and one other shot of him in the air before he hid in the non-dead trees.

Eight Space Shuttles

I know you guys are getting antsy to see some space shuttle pictures, so here's a little composite I threw together. You can see space shuttle Atlantis on STS-129 this past Monday lifting off from pad 39-A at Cape Kennedy. Pretty cool, eh? I took these shots with my Rebel XSi set on manual at 1/400 of a second, f/8, ISO 200. I used a 400mm lens on a 1.6 crop sensor for a length of almost 650mm, and with a polarizing filter to boot. Oh, and did I mention I was 6 miles away? I thought these were awfully good for being so far away.

Uh-Oh, Part 2

Well, bad luck just seems to follow me around some days. And it seems to be following even more closely lately. After losing my entire hard drive a week or so ago, yesterday I lost my camera. Well, I didn't lose it, but it no longer works. After shooting the shuttle launch as far as the separation of the SRBs, I turned my camera back towards the pad to get some pictures of the lingering steam and smoke. I didn't notice anything odd until the camera quit auto-focusing. I took my eye away from the viewfinder to see a message on the screen. Error 99, it said. Turn the camera off then back on, it said. But that didn't help, it just came right back. I'd seen an error 99 before when I rented an incompatible lens. Pulling the battery out for a second worked then, but not this time. I tried the battery, the battery holder, the lens itself, the memory card, nothing made a difference. Once I got back to a computer, I loaded up the pictures from the memory card (for a while I was worried that none of my pictures would be there, but they were OK). The last dozen or so pictures on the chip were obscured, as if something was in front of the lens, but I knew there had been nothing there while I was shooting. The three pictures you see here are the last three shots from the launch.

After much messing around with the camera itself and some internet searches, I finally discovered that it's a shutter problem. Digital cameras have shutters just like regular cameras. The shutter exposes the image sensor to light for the prescribed amount of time, just as it would expose film. Well, when I peek behind the mirror in my camera, I see the closed shutter when I should normally be able to see the image sensor. I've got a feeling the price of fixing the camera is going to be all too close to the price of a replacement camera.

I suppose I should be happy that my camera didn't break until after the launch. Five minutes earlier and I wouldn't have gotten any of the awesome pictures I did. But I'm still unhappy that it's broken. Anyhow, stay tuned for some of the more awesome final pictures from my camera.

A Tale Of Two F-Stops

Here's a short lesson in photography for you. Both of these pictures were taken with the same camera, one right after the other. The only setting I changed in between the two shots was the f-stop. The one above was shot through a really small opening, something like f/22. The one below is wide open, f/4 I think. Notice that in both cases the mushroom is in focus, but the picture above has more of the leaves around the mushroom in focus, while the picture below has out-of-focus leaves. That's depth-of-field. The rocks in the background are in a stream maybe 20-25 feet below the mushroom, and they are almost in focus above, but you'd have a hard time telling what they were in the picture below. Cool, eh? Problem is, to get the wide depth of field (the small f-stop or larger number), you need a longer exposure. I was using my new tripod, and the exposure probably took 20-30 seconds. There's always a trade-off.

Temporary Glass

Sorry about the lack of updates this week. I've been really busy with work and here at home, too. I'm on the road all next week, so I've been trying to get prepared for that. And one of my preparations was to rent a fancy lens for my camera. It showed up yesterday, but weather issues kept me from shooting anything until this afternoon. It's a Canon L series lens, EF 24-105mm f4 IS USM. Gotta love all those initials making the end of the glass heavy. The most important of those letters is the L, that means this is a professional lens that should yield some really sharp, bright pictures. Check out the bird of paradise above, zoom way in, and you'll see it's really sharp. And I hope that with some experience, I'll get even better shots. Stay tuned for more samples! And see you next week in Ohio!

A Much Needed Cleaning

I congratulated myself earlier today on having had my camera for a whole year now, but in that time I've neglected some of the maintenance and upkeep on it. Case in point is a good cleaning of the image sensor. The Rebel XSi has a built in image sensor cleaning function, but it only forestalls the inevitable cleaning process. Each time you change a lens, a little bit of dust gets into the inner chamber of the camera. Some of that gets past the internal mirror, lands on the image sensor and sticks. Some of what gets that far inside is shaken loose by the automated sensor cleaning that activates each time you turn off the camera, but the nastiest stuff sticks and never lets go. After a while, you start to notice dark spots in your pictures under certain lighting conditions, especially against open backgrounds like clear blue sky. I knew it was a problem that needed addressing before I went to Washington, DC, and I tried to fix it in a hurry, but I didn't do a good enough job, and I saw spots on every single picture I took while in DC. So this afternoon I sat down and did the job correctly. The picture above is an image of my sensor before I touched it, heavily tweaked and processed to show you the gunk on the surface. (I think those streaks are dust on my computer monitor, actually, not the image sensor, but the black bits are in my camera.) The photo below shows the after version of the same image, with most of the spots gone completely, and the ones that remain are extremely small. Certainly worth the time it took. I only wish I'd done it right before my trip.

I had to do this with my last camera as well, only I waited much longer and wound up with many, many more spots before I addressed the problem. Click here for before and here for after images of that time.

Happy Anniversary

Congratulations to my Canon Digital Rebel XSi! It was one year ago today that I bought my new camera, and I haven't put it down since. Let me see, since that day last year, I've shot approximately 45,044 pictures. That means I've averaged well over 1oo shots a day for the entire past year. I know it sounds impressive, but you wouldn't want to see most of those. I believe that quantity creates a quality all it's own. Here's to another 365 days of the old camera, maybe with a new lens or two...

See Spot Run

You may remember last week when I showed you some images of my CMOS sensor down inside my digital camera. It was covered in spots that were showing up on my images as little shadows. Well, I got my cleaning kit today, and Voila! No more spots! Or at least not as many. I can still see a few along the top edge, but nothing like I was shooting through before. Now I can shoot the Airfest this weekend, and not worry about having to touch up each and every one of my photos afterwards.

Run Spot Run

I've been saying for a while now that I need to clean the image sensor on my camera. And here's the shocking proof. The images above and below are shots taken of a plain white background with the aperture stopped way down, making it a long exposure with just a small amount of light entering the camera. It's also deliberately out of focus and handheld, so anything sharp on the final picture is internal to the camera. The black dots you see are pieces of dust, dirt or some unknown sort of crud on the image sensor in the heart of my camera. I suppose this is the price you pay for having a camera with a removable lens. Every time I change lenses, the interior of the camera is exposed to the elements for a few seconds. Over time, a mess builds up. I need to either learn to clean it myself, or get someone to do it. I'm reading up on the process here. FYI-looking at the image sensor doesn't reveal much of anything. I can't spot anything on the surface. I'm probably exposing it to more dust just by opening it and looking. What's the difference between these two shots? The one above is at a lower ISO setting (100). That means I should get a clearer picture with less noise in it. The shot below is at ISO 800, and I think it's a little rougher. Both shots were processed in Photoshop to highlight the defects. I find the dark corners interesting, too. I guess the better your lens, the less of that you get.

So, what effect is this dust having on my final pictures? Plenty. That big chunk at lower right shows up in just about every picture I take of the sky. It's there in all my pictures, but it's often mixed into the image such that it's hard to spot. But it's still making my images less sharp. I really blew the contrast out of the water, but the image below shows the spot. I see it on almost all of my shots, always in the same place. If I want to use the picture, I have to spend a few minutes in Photoshop trying to clone over it. It's a pain.