Doug Stockdale's Singular Images

April 7, 2018

Canon 24-105mm lens test revelation

Filed under: Photography — Tags: , , — Doug Stockdale @ 8:30 pm


detail (100% magnification), Canon 24-105mm L f/4 lens, at 105mm at f/9 copyright Douglas Stockdale

Last Friday I had found myself in the local Canon Service shop in Costa Mesa regarding some issues with the bottom left corner of my images and was informed that I need the flange back repaired for my 5D Mark 3. sigh. I picked up the “adjusted” body yesterday (Note: next to me was a guy with a sad face as he was just informed that his 5D Mark ? needed the same repair. He was also holding a big 300mm prime lens. Canon crappy camera design and construction strikes again) so this morning I decided to perform a quick camera check on my adjusted body, just to make sure everything is okay.

I mounted my 5DMk3 on a tripod and then set the aperture to f/9 to make sure that the lens was stopped down enough so that a narrow focus would not be an issue. My first test was my Canon 50mm f/1.4 prime lens; results exhibit nice sharpness edge to edge, image below. Appears my flange back adjustment is fine. Then being a curious cat, I then mounted what I suspect was the bad-boy lens that created the flange back to go out of alignment, my “heavy” 23 oz Canon 24-105mm L f/4 lens. Similar to the 50mm f/1.4, I set the f/9 for exposures for the 24mm, 35mm, 50mm, 70mm and 105mm focal length tests.

At the 24mm, 35mm and the 50mm focal lengths exposures, excellent edge to edge image sharpness (bottom, below). My surprise was the amount of  corner softness that occurred at 70mm (below) at 100% magnification, now more like “average/poor” and even more corner softness at the 105mm focal length (above) bordering on “poor/unacceptable”. I am guessing on first looking at the image below that these might all look acceptable, but when making 16×20″ prints or larger, the corner softness starts to become more noticeable.

I have had the Canon 24-105mm lens (purchased new) since I acquired my used Canon 5D in 2010. I had never tested this lens out since the initial images on my monitor appeared fine. I usually am composing with something in the 24 to 50mm focal length, so probably unknowingly I was in the sweet zone for this particular lens. On a couple of occasions I composed using a focal length between the 70 to 105mm range for some informal portraits, but now remember being a bit disappointed that the images appeared a bit soft. Since portraits are not my usual thing, I just kept moving on, also I did not think I would use a 100mm prime lens that much to make an investment.

Bummer about the Canon 24-105mm lens results. So this lens is now sitting on the storage shelf as I contemplate selling it, while the 50mm f/1.4 is on the 5DMk3 (camera on it’s back with the lens straight up, no off-center weight on the flange back). As potential replacements for the 24-105mm I am thinking of a lighter Canon 35mm f/2 (prime) lens and a Canon EF 100mm macro f/2.8 (prime) lens. I all ready have a Canon 17-40mm L lens (which I have not test yet, but think I will sometime soon) so I have the 24-35mm focal lengths covered. For the 100mm macro, I need to consider if I want the heavier L lens which now has the IS (Image Stabilization) feature, although only 1 oz difference in weight it’s not really much difference. The 100mm macro lens is close to the weight of the Canon 24-105mm lens, so I would need to be careful how I carry it when it’s mounted on the camera body, or just mount it when I need it.

No more trips back to Canon to repair the flange back again! I hope you enjoyed my morning in the back yard.



full frame (above), 24-105mm lens at 105 mm focal length and f/9


full frame (above), 24-105mm lens at 70mm focal length and f/9


full frame (above), 24-105mm lens at 35mm focal length and f/9


full frame (above), 50mm f/1.4 lens at f/9

March 31, 2018

Canon 5D Mark 3 – Flange back repair (again)

Filed under: Photography — Tags: , , — Doug Stockdale @ 12:04 am

10-17-16 detail KI6A3918

Bottom left corner detail 2016 copyright Douglas Stockdale

I recently left my Canon 5D Mark 3 body at the Canon Service center in Costa Mesa for repair of the “flange back”, which the camera technicians stated was the reason for my latest series of crappy-corner images. Latest, in as this is the same image issue I had with my earlier Canon 5D (the original 5D).

The image issue is that that apparently something tweaks the “flange back” interface on the camera body, the interfaces with the camera lens mount, in such a manner that the sensor plane is out of alignment with the lens focus point. The image artifact, photo above, is a slightly soft out of focus region within the image capture. Regretfully, this is a really small area on an 8 x10″ image and for me, not noticeable until you decide to make 16 x 20″ prints, and especially when you make 30 x 40″ prints.

The Canon camera tech tells me that I must have dropped the camera (nope, did not do this), use a really big lens (rarely use my 70-200mm L lens) as I almost exclusively have the 24-105 mm L lens on the 5Dmk3, or maybe just a lot of weight by a lens on the camera over time. Okay, so for the later, I carry the 24-105 mm L lens on my 5DMk3 for long duration’s on my shoulder as I walk-about. Now the 24-105 mm L lens is the “kit” lens that Canon likes to sell/push for the Canon 5D series bodies. So what I am to understand, the 5D series of bodies is not designed or built to carry their kit lens for long durations. WTF!

Oh yes, this is not a warranty issue, so this little repair is costing me 219 bucks. Canon wants me to bring in the 24-105 lens to make sure it’s not tweaked either. For the earlier fix of my Canon 5D, there were other shutter issues as well, so Canon replaced the shutter and adjusted the flange back that time under warranty; no cost to me. But NOT this time; I am guessing from their perspective I must have done something wrong. I am now guessing that Canon sees a lot of these flange back issues (first thing that the tech stated could be the problem).

Reminds me of the commercial of the car needing repair regarding the insure company; maybe I have the wrong camera system. Mind you, I have been using Canon camera equipment for over 30 years, but this is more than two strikes as I have a ton of crappy corner images to show for it, both from my Ciociaria project (2 and half years back and forth to Italy, 3,500 + images, with the 5D), and now the Middle Ground project, as I find this corner issue going back to October 2016 for a project that I thought is complete (a year and half of work, 2,000 + images) and currently working with a printer to self-publish a photobook in the next couple of months. Again; WTF!!

I have not seen any alerts from Canon to be watching for this issue with this camera body and lens combination (have you??). Second, this defect is not something I notice until I make some big enlargements and I do not create these until later in the project development. The sample photo with this post is a big enlargement of the corner and even then, not really apparent. So if I stay with Canon, I am assuming that they expect me to continually monitor the corners to ensure that their crappy designed camera is still okay to use. Also assumes that once Canon fixes this, it’s permanent fix, but now I am doubting that; so if I keep this rig, I need to be constantly monitoring my photos for potential camera equipment defects. I would rather be concerned about the image composition and lighting, not crummy photo equipment.

So I am taking inventory of all of my Canon equipment and accessories and evaluating some alternatives, like Nikon. All of this while I was starting to evaluate a 24″ wide-format Canon printer to replace my Epson 4800. Maybe staying with an Epson printer as well.

Not a happy camper. Not someone who is going to be quick to recommend Canon.

May 15, 2017

Canon not supporting original 5D camera

Filed under: Photography — Tags: , , — Doug Stockdale @ 8:00 am


Canon 5D body copyright 2017 Douglas Stockdale

Maybe I might not be the last person to find this out, but I now know that Canon Service is no longer providing support, either maintenance, repair or replacement parts, for the original 5D body.

I found this out last week when I drove over to Costa Mesa to the Southern California Canon Service center to have my Canon 5D body serviced. The back screen was not functioning properly as the after image capture in the display was posterized. I could see if the composition was correct, but could not tell if the exposure was correct by visual examination, as the histogram can only tell me so much.

The back screen has actually not working correctly over a year ago and one of the reasons that I finally made the investment in the Canon 5D Mark 3. Since I did not have the funds to fix the 5D back at that time so I just figured I would wait a little until I did. Apparently I waited a bit tooooo long. crap!

The good news is that when the shutter was not working well a couple of years before, I did take it into Canon service and they replaced the entire shutter system under warranty, which was very nice. So now I have a relatively new shutter but a piss-poor back monitor so this was not going to make it easy to sell or trade this 5D as its value was now about zero.

Okay, then the Aha!

For my Norman strobe lighting kit, the Canon 5D system needs to have the camera set to Manual and then dial in the lens aperture and shutter speeds. Once I had the right exposure combination for my studio to photograph the books, the exposure was essentially locked in (1/125th of a second at f/16). I did not really need to check the camera’s back monitor any longer. Sort of reminds me of the old 35mm film days; shoot with confidence and find out later if there are any issues. The good news is that the time and distance to check my studio results is measured in minutes and feet. The alternative is to hook up a USB between the camera and a computer as a tethered system, but I did not want to hassle with the required cable, plus I do not have a great place to set up the computer (right now).

The second part of this is to add on a dedicated lens to the 5D body, which I have been experimenting with various focal lengths to photograph book interiors for the past couple of months. I had come to the conclusion that a 50mm lens on the full frame 5D would work fine; thus I acquired the Canon 50mm f 1.4 lens to complete this studio set-up and I did a quick test with it yesterday after purchasing the lens. This is the set up below, with the PocketWizard PlusX in place to trigger the strobes, on top of my Norman P2000 power pack. I also went the little extra with the Canon lens hood as the knock-offs from China are dirt cheap, but do not come with the matte interior lining to deaden any potential reflections.

So now I looking forward to the next set of books to photograph for The PhotoBook Journal. I will probably have this camera & lens working in the studio for the next set of reviews by the end of the month. And I found a great use for the 5D body and what I might call a win-win for me.




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