Why do I sometimes get a shaking viewfinder image in my Canon 550D?

Question

Sometimes I put my viewfinder to my eye before I turn on my camera. When I turn it on, the viewfinder image slightly shakes and moves a bit vertically. This also happens when I look through my viewfinder and press the shutter when the camera has been on, but not used for several minutes.

My camera is a 8 month old Canon 550D and I use it with a Sigma 18-50 mm f/2.8-4.5 DC OS HSM lens.

As it happens sometimes, the behaviour is hard to reproduce and hence I can not give you more information about the problem.

Does anybody know why this is happening?

Asked by Bart Arondson

Answer

As forsvarir says, it's most likely the optical stabilisation initialising.

And to clear up one of you comments; In a DSLR you will only see a stabilised image in the view finder with a stabilised lens. When you look through the view finder you're not seeing a picture that have been captured by the sensor first. So any stabilising happening on the sensor is not visible through the view finder.

With a mirror-less camera where you use the screen instead of a view finder, sensor stabilisation will be visible.

Answered by Håkon K. Olafsen

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Are these images symptomatic of shutter failure?

Question

This is a burst sequence taken with a Canon 1D Mark II N in high-speed mode (8fps). You can see the bright line down the center and the dark area in the upper-right. I have several other sequences with similar artifacts.

Is my shutter failing, or is there something else going on?

Shutter count utilities at http://www.foxbat.me.uk/2.0/index.php#/1dcount and http://www.camerashuttercount.com/ both indicate a shutter count of ~79,000, though I do not know the accuracy of these sites, nor do I have an estimate of the camera's shutter count as I got the camera used with no pedigree. My understanding is that this particular model's shutter life expectancy is around 200,000 actuations and I've heard of people getting over 400,000.

---

UPDATE: I decided to crack it open and inspect the darn thing:

Seems pretty conclusive that it's the shutter, though if anyone wants to dispute the claim I'm game to entertain it :-) Guess it's off to the shop...

Asked by djangodude

Answer

My guess for the shutter speed in the comment was based ob the approximate width of the bright strip relative to the image width, multiplied by the sync-speed. I assumed a 1/250sec sync speed.

Just a speculation: it looks like the shutter blades get stuck for an brief instance around the middle of the frame. It is possible that you have a piece of dirt stuck there, or that the spring or rails are about to fail. Try to decrease and increase the speed by a stop and see if the stripe gets twice as wide and as narrow. If so, it is indicative that it is indeed the shutter having a problem.

UPDATE after the mystery was resolved - I'd think the first thing to do (OK, maybe the second) would be to remove the lens and have a look at the internals... but that's just me ;-)

Answered by ysap

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What is the sound that I'm hearing from Canon EF 24-105mm F/4 L lens?

Question

I've a Canon 600D with Canon EF 25-105mm F/4 USM L lens. When I half press the shutter I can hear the US motor sound trying to focus on my subject, however I hear another sound, it's lower than the sound that the US motor makes when it's trying to obtain focus. And when I raise my finger of the shutter I can hear that the sound of the US motor has stopped while this other sound is still going few seconds and then it stops. I wonder what is this sound?

Asked by Akram Mellice

Answer

You're hearing the IS start to activate.

Answered by rfusca

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Why do I get two JPEG files instead of RAW+JPEG when transfering to my computer from my Nikon D5100?

Question

I have a Nikon D5100 and I want to shoot RAW and JPG at the same time. I select RAW+N (RAW plus Normal Size JPG). Now when I export the shots to my computer I end up with two files called DSC_0123 (1).jpg and DSC_0123.jpg. (Both files are the same size). I am missing the raw NEF file. Why is the camera doing this and is something set wrong?

Note: When shooting in RAW only the files are produced normally and function as expected. The firmware is the latest Version (1.01). I have 3 modes for RAW + JPG -- They are RAW+B (Basic) RAW+N (Normal) RAW+F (fine) all three produce JPG and no raw file.

Here are a few ideas that I have tried:

• Reset Camera Settings
• Try another memory card (Note: The memory cards I have are all Transcend 16GB Class 10)

Asked by Lynda

Answer

From reading http://forums.dpreview.com/forums/readflat.asp?forum=1034&message=38261447&changemode=1

and

http://forums.dpreview.com/forums/readflat.asp?forum=1034&message=21930545&changemode=1

You will need to have Nikon's Transfer software or use View NX 2

UPDATE: As a side tip (maybe you already do this) but I never connect my DSLR to the PC I always use one of these - Bottom line is - I dont want something to go wrong with my camera on the PC - I would much rather a memory card take that hit.

Answered by Rob

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Nikon D5100 - Saving RAW and JPG Files

Question

I have a Nikon D5100 and I want to shoot RAW and JPG at the same time. I select RAW+N (RAW plus Normal Size JPG). Now when I export the shots to my computer I end up with two files called DSC_0123 (1).jpg and DSC_0123.jpg. (Both files are the same size). I am missing the raw NEF file. Why is the camera doing this and is something set wrong?

Note: When shooting in RAW only the files are produced normally and function as expected. The firmware is the latest Version (1.01). I have 3 modes for RAW + JPG -- They are RAW+B (Basic) RAW+N (Normal) RAW+F (fine) all three produce JPG and no raw file.

Here are a few ideas that I have tried:

• Reset Camera Settings
• Try another memory card (Note: The memory cards I have are all Transcend 16GB Class 10)

Asked by Lynda

Answer

From reading http://forums.dpreview.com/forums/readflat.asp?forum=1034&message=38261447&changemode=1

and

http://forums.dpreview.com/forums/readflat.asp?forum=1034&message=21930545&changemode=1

You will need to have Nikon's Transfer software or use View NX 2

UPDATE: As a side tip (maybe you already do this) but I never connect my DSLR to the PC I always use one of these - Bottom line is - I dont want something to go wrong with my camera on the PC - I would much rather a memory card take that hit.

Answered by Rob

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Is it normal for the LCD screen of D3100 to sometimes show moving horizontal lines?

Question

Yesterday I noticed horizontal upwards moving lines on the LCD screen on the D3100 when I was using live view.

It doesn't happen always, is this normal?

Asked by Anisha Kaul

Answer

It's completely normal under artificial lighting, when frame rate of your camera matches closely flickering rate of the light source (usually determined by frequency of electrical network). If the electricity frequency is n times higher, there will be n lines on screen.

When the frequency matches exactly, dark/bright phases of light flickering will always fall during time when camera reads the same row of pixels and those rows will seem darker/brighter. Now, if the frequency match is not close, but only approximate, a cycle may fall on a neighbor row compared to the preceding cycle those darker/brighter lines will appear to be moving. This is not a camera defect, just a result of two engineering solutions (in light source and video capture) using frequencies invisible to human eye becoming visible when used together.

Answered by Imre

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I cannot open the internal flash on my Canon 60D camera; how do I fix it?

Question

I tried opening the internal flash on my Canon 60D camera the other day and it didn't open at all. I couldn't understand why. After messing around in the menus, I found out that the camera thinks that an external flash is attached. It gives the message "This menu cannot be displayed. External flash is attached."

How do I fix this?

Providing a few photos to explain what happens here. Sorry for the low quality, obviously I couldn't use my 60D to shoot photos of my 60D :))

Asked by RiMMER

Answer

There is a little microswitch in the hotshoe that detects an external flash -- this may have become stuck, or got a piece of grit blocking it. If you cannot see anything under the rails, you may have to take it to your local friendly Canon authorised repair centre, but if you can see some grit, you may be able to carefully remove it with a cocktail stick or similar.

Answered by Rowland Shaw

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Why did my Canon EOS 450D fail to save the entire photo?

Question

After not being used for three months I got this (bottom right corner cropped from processed raw image by Canon's DFP):

(original RAW is available for download here: http://dl.dropbox.com/u/9271284/IMG_9766.CR2)

This was first photo taken that day, all photos taken after were saved ok. Is this a failing SD Card or first sign that my EOS is going bye bye?

Asked by Vnuk

Answer

Looking at the raw file, the JPG preview looks fine, but there is about 1/6th of the RAW image that is blanked out.

It could have been a glitch in the camera, an error on the card, or an error in the transfer to your computer.

If you still have the image on the card, I'd try to transfer again.

Then reformat the card and see if it happens again.

If it does, try other cards, as Rowland suggested.

If other cards have the same issue, then suspect the camera. Until then I'd think a faulty card or transfer is more likely.

Answered by MikeW

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What should I do about this strange CF behavior, where I lost tonight's pictures?

Question

I have taken over 14,000 photos with my Canon 7D and loaded them into my Windows 7 desktop computer the same way, by inserting the CF card into my computer's reader. The point is that I know how it usually works so this "empty folder" problem is definitely out of the ordinary. To shorten the post I always use the "Safely Remove Hardware and Eject Media" utility before removing the CF. My workflow has been folder based:

• Shoot into a folder.
• Copy the folder to both an internal hard drive for editing etc. and an external hard drive I swap every few days as off-site backup.
• Create a new folder for the next batch of photos, unless the card is about out of space. In that case I format another CF card and remind myself to swap offsite HDs soon. The full card goes in my camera bag, which is my semi-offsite backup against the house burning down.
• When I swap offsite disks I format the CF card in the 7D and move the other CF cards to the "Ok To Use" pocket of my camera bag. If I have time I'll format them as I move them.

I shot tonight's sunset into folder 102EOS7D. Folders 100EOS7D and 101EOS7D had the photos of the two prior shoots since the last offsite backup swap. I put the CF card in the PC and both the last two folders were empty, 101 and 102. I put the CF card back in the 7D and confirmed that both folders 101 and 102 had pictures in them. I attached a USB CF card reader to the PC and inserted the CF card. Folders 101 and 102 were still empty. I put the CF card back in the 7D and the folders were empty! By just trying to read the CF card two shoots of photos went away! Bummer!

I have the photos from folder 101 and tonight's sunset in folder 102 was boring so I decided to troubleshoot rather than try to recover the CF card. I ran Windows Update and nothing was missing. I reformatted the CF card and shot some photos. I found a USB cable that fits the 7D and successfully downloaded the photos in the new folder 100EOS7D.

Any suggestions? The card is fairly new, only in its second or third offsite-backup-swap cycle. It is the largest capacity I've ever had, a Transcend 400x 64 GB CF card.

More details:

• I always format in the camera, not Windows.
• Losing photos is serious, how do I help keep it from happening again?
• Is this likely a CF card problem, a Windows problem, a problem with my 7D, or ... ?
• I don't know if this is a possibility, but could there be "bad blocks" in the "FAT" (or whatever, don't know tech details) of the CF card that could produce these symptoms?
• Is there a low-level format utility for CF cards that could identify "bad blocks" and "mark them unusable"? Again, I'm not familiar with CF card details.
• Is there something, given the symptoms, I don't know enough to ask?

Asked by Mark Jerde

Answer

CF cards – just like any other storage media – fail every now and then.

In general, when a storage media fails, the symptoms may "look strange" from the perspective of the computer, camera, or any other device that tries to access it. Don't try to over-interpret them; it just failed. You might be able to recover something – for recovery tips, see these two questions: [1], [2].

There is nothing you can do to completely prevent failures, no matter what kind of best practices you try to follow.

To make failures less frequent, you can try to use well-known brands, expensive high-end cards, and cards with a long warranty period. Also remember to throw a card away (or have it replaced) immediately as soon as you notice anything strange.

But most importantly, make sure that losing a single CF card is never a catastrophic event. Use two cards in parallel if your camera supports it. Transfer photos from the card to your laptop or some other backup device frequently. If you don't have access to any kind of computer for a while, use more than one card and rotate them; etc.

Your card will fail, sooner or later. And your hard disk drive will fail, sooner or later. Just plan ahead so that you won't be too upset when it happens. Sure, you may lose some photos, but make sure you don't lose a whole week of memories.

Answered by Jukka Suomela

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Why does my Canon 550D make a small sound while focusing?

Question

Ok the "noise" I am talking about here is not noise in photos, it's actual small noise/sound coming from camera.

I have been using my camera for around 6 months, but never noticed this before. May be because I have been with people/outside. Last week I was sitting alone at home, and focusing on an object when I noticed small noise from sensor. The noise comes only when I half press the shutter button to auto focus, and stops as soon as I take off my fingers from button. The noise is like a computer fan..but not that loud of course. Should I assume this to be normal?

Asked by vishal.biyani

Answer

The only sound that would come from the sensor itself would be a self-cleaning function, which only happens when you run the self cleaning, or turn the camera on/off. The sensor vibrates to shake off dust. This would not be happening when you are shooting.

When you half press, the sounds you might hear would be from the lens AF motor or image stabilisation (IS). Try putting the lens in manual focus and turn off IS if your lens has it, and see if you still hear a sound.

Answered by MikeW

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What is the reason for underexposure in my film photographs?

Question

Thanks to all the quality answers I got here that helped me to buy a film camera. I got my first roll of film processed and printed.

The print results are not as pleasing as looking at the slides through a loupe (50mm lens). One example is here. It is underexposed and has a purple tint. This is not the only one, all photos have similar characteristic.

Details and settings:

• Camera: Nikon F100
• Film: Velvia 50
• Metering: Matrix

I want to know the reason for underexposed and purple tinted photos. And what should I do to avoid this.

Asked by Vikas

Answer

The purple cast is typically Velvia - learn to love it, embrace it and you'll get some stunning results. The underexposure is a compound of two things - firstly your camera is compensating and trying to make the snow appear as a mid-tone, and secondly Velvia is known for being a bit slow, many people rate it at ISO 40 or even ISO 32.

When shooting Velvia remember that you've only got 4 stops of latitude, in order to record this scene properly I'd meter the snow with a spot-meter, and then pull this up to the highlight by over-exposing that by 2 stops. You'll then get far more detail in the dark areas, and your snow will be sparkly white.

Answered by Arthur Dent

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Why do my images get distorted on my Nikon DSLR?

Question

I have had my Nikon D40 for a while, and some of the pictures are coming out distorted. Two examples are below:
So my questions are:

1. How do I fix them after the fact? - i.e. after they have been imported from the camera - if possible
2. How do I prevent future pictures from being distorted like this?

Thanks
and

Asked by marcamillion

Answer

Likely culprits, in order of probability:

• Bad SD card (by far the most likely).
• Bad cable or card reader.
• Something horribly wrong with the camera's electronics.
• Something wrong on your computer.

The "bad card" scenario is, unfortunately, the most likely, and in that case the pictures are lost. If it is just the reader, transferring the files again might work — but you've probably already tried that. If you reformat the card, it might work fine, but I sure wouldn't trust it.
Bad cards are a fact of life... I buy only brand-name pro-level cards. They're more expensive (possibly exploitatively so) but I think the extra quality guarantee is worth it.

Answered by mattdm

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What might cause stuck focus on a manual lens?

Question

So, today I dropped my ME Super. When I picked it up I realized that the focus ring of the 50mm f2 lens attached didnt turn. My question is, what could cause this? Could it be that the threads inside the lens which move the glass about are binding?

Answer

My problem was that the threads that move the elements were jammed. I was lucky as in this lens, a Pentax SMC-M 50mm f2, all of the glass was contained in a unit and a thread moved it back and forth or obtain focus. These threads had slipped and basically they were cross threaded. I would never try this on an autofocus lens or a zoom lens. That would be WAY to complicated. Even with a prime lens it took a lot of adjustment to get the distance scale correct and I couldn't even begin to imagine what a nightmare it would be on a zoom lens. Sorry jrista, a step by step would look like this: Disassemble Repair Reassemble Check focus Disassemble Adjust Reassemble And repeat......

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Why is there a strange white spot on all of photos from my Zenit-B SLR?

Question

I've taken some photos with my old Zenit-B camera. And I have some strange white spot on all of the photos in the upper right corner. Sometimes it is not too recognizable, but it is everywhere.

It looks like condensate, but I can't see anything like that on the lenses when I open camera. Also it is quite strange that this spot even appeared on absolutely dark photo.

Does anybody know what could it be and how could it be fixed?

Answer

I would say light leakage and possibly internal reflections of some sort.

Considering you get a "bright patch" in the top right, I would highly suspect there is light leaking in.

The "dots" look a lot like reflections to me. In the lens, on a piece - anything that is shiny and reflects light.

I'd say start by checking whether the back closes properly. Next check if you have light leakage from the viewfinder.

Lastly, have a good look if you can see a reason for reflections in the camera.

If none of the three turn up something, try a different lens and see if the issue still occurs. If no, then it is the lens, otherwise... I'm out of ideas...

A last common option for failure would be the shutter, BUT that tends to look rather different.

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What is causing this white spot in every photo with my D90?

Question

Recently I noticed that the photographs from my D90 has an odd white dot in it. The dot is present in every image. The dot becomes clearly visible as I zoom into the image. I have attached a photo taken with dark background and marked the white spot.

What could be causing this white spot? Has any had such issues? Sample image with marked white dot http://imgur.com/trYbG

Answer

This is most likely a Defective Pixel. There's not much you can do about it aside from cloning it out in Photoshop when it is obnoxious. Are you doing a lot of long exposures? Back when I was doing astrophotography I'd see a bunch of dead pixels in my camera, but never saw them in regular use. So it may be related to sensor time.

You can always contact the manufacturer and see if they have a defective pixel policy. You may get it fixed!

---

Hmmm, I just fully read the wikipedia article. By their definition, the pixel in the camera sensor would always be off, not always be on! But I tend to doubt that, on or off, they are still defective. This article over at Ken Rockwell's site calls them hot pixels. Same thing in my book. Hot, defective, whatever...

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Why am I getting dark spots with my Singh-Ray 77mm vari-ND filter?

Question

I've been using a Singh-Ray vari-ND with my Panasonic GH1, and I'm seeing obvious dark spots in the image. On a lower setting the left and right side of the image have dark lines and when I go to a maximum setting the dark sides cave into the middle and forming a circles and it looks really bad. I've been using a 20mm lumix 1.7 lens, and I read that the vari-ND shouldn't be used with lenses wider than 35mm in full-frame terms (which mine would be a 40mm after the micro 4/3 conversion) due to the polarized filter. Could this be why? Or is my filter defective?

Note that my hand is slightly in this last image, and is the cause of the darkened upper-right corner.

Answer

The third image looks like vignetting due to the thick Sing-Ray filter and your step down rings. But strange it's only in one corner - you don't have a hood attached do you? You should be able to see this vignetting through the viewfinder.

Even a normal polarising filter is going to result in uneven skies with wide angle lenses, with the sides often being much darker, due to the wide field of view (light coming from vastly different angles through the filter). With variable ND filters, this effect is multiplied.

The solution is using a longer focal length, if possible, cropping out the sides, or reducing the filter density.

The number of stops you can reduce with these filters goes down as the lens focal length goes down. You might be able to reduce 8 stops at 135mm, but only 5 stops at 20mm.

Your 20mm (effectively 40mm) is close to the 35mm limit they mention. It's a gradual thing, so if it's not recommended at 35mm, it's probably not ideal at 40-45mm and you can expect some vignetting or strange colour casts at the edges, and these will move more to the centre of your images the wider you go.

From their website:

NOTE: Due to the nature of the Vari-ND Filter, its "profile thickness" is significantly greater than most filters (14.2mm for standard mount, 10.5mm for thin mount). The profile thickness of either version may cause vignetting when used with wide-angle lenses, especially on cameras with full-frame sensors. Due to the vast number of combinations of cameras, lenses, and other factors, we can NOT predict under what circumstances vignetting will occur, and to what degree. We suggest simply adjusting your focal length, position, and/or composition to remove the vignetting -- use your digital camera's display for reference.

NOTE 2: The design of the Vari-ND Filter may introduce irregularities when used with very wide angle lenses, especially on full-frame cameras. Adjust your focal length and reduce the filter density setting until the irregularities disappear

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Is it normal for the Canon kit lens to exhibit lens flare even without a UV filter?

Question

I recently bought a Canon 550D and have been experimenting with this for a week. I have been pretty satisfied with the quality, until I faced this lens flare problem. Notice the unwanted blue light near the red board with yellow star:

Attached are two pics

1. Shot with Canon 550D - 18-55 kit lens with UV filter on:

2. Shot with Canon 550D - 18-55 kit lens without UV filter on:

Is this level of lens flare normal? Or are there any quality issues with my camera?

P.S.: Pics are little blurred — I have quite shaky hands.

Answer

Yes, this is normal. It's important to realize that this is almost entirely to do with the lens and not the camera body. See What causes lens flare? for more detailed background, but basically, flare is the result of stray light bouncing around, and is common with lower-cost lenses and with wide-angle lenses — and the 18-55mm kit lens is both.

You can see that the problem is worse with the UV filter. A large, flat, and probably cheaply-coated glass element is ideal for bouncing light (but not so ideal for avoiding artifacts like this). A higher-quality filter will contribute less to the problem, but won't improve the lens itself. A higher-quality lens will have a design intended to protect more against random bouncing light.

A cheap thing you can do to help, though, is to shade the lens from out-of-scene light. You can use your hand or a piece of cardboard in a pinch, but really this is what a lens hood is for. It screws on the front of the lens and keeps some of the "extra" light away. (For your Canon kit lens, the item you want is the EW-60C lens hood.)

Of course, that won't help flare caused by lights in the scene (as in your image, where the blue ghost light appears to be caused by the bright white lamp on the building). For that, the best option is to compose differently — move so that light source is obscured, or just hits the lens in a less-obtrusive way. If that's too limiting — sometimes, that's the picture you want to take! — a lens which better controls flare (which is to say, a more expensive lens) will help get this kind of shot.

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What should I do about Canon PowerShot “Lens error, restart camera”?

Question

I've had a Canon PowerShot A1100 IS camera for almost a year now.

About a week ago, I went on a trip, took pictures the whole trip, everything was ok.

When I got home, and tried to turn the camera to move the pictures to my PC, I got an error: "Lens error, restart camera"

The lens doesn't even start to open, doesn't make any sounds of trying even.

What can I do to fix this?

Answer

Lens errors are fairly common. Usually it's sand or grit interfering with the lens extension mechanism. Or the camera's been dropped with the lens extended. Or the camera has been powered on, but the lens had been blocked preventing its extension.

I have written a blog post about some things that you can do to try to correct it. They only seem to work for about 50% of lens errors, but they're worth a try.

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What is the source of excessive noise in images from my D7000?

Question

I'm a beginning photographer who recently invested in the following setup:

Nikon D7000 camera body, 15-105mm Nikor kit lens, 150-500mm Sigma lens.

We recently made a trip to the Pantanal, Brazil where we made heavy use of the Sigma lens. Upon returning home, we noticed that those photos contain an excessive amount of noise. Below is an example of an unprocessed photo:

As you can see, even without zooming in particularly the unsharp areas have serious noise. And as I usually up the contrast of such an image, the noise gets even worse. I shoot mostly in aperture mode, and in this case the ISO was at 640, in order to be able to have a shutter speed that allows me to shoot without a tripod (other meta: F6.3, focal 500mm, 1/320s). Still, the D7000 is known to be able to handle high ISOs quite well, so I'm surprised to see this kind of noise at this ISO already.

I know how to get rid of noise, using both Lightroom and Noise Ninja, but the amount is so excessive that via luminance I'm losing too much detail. So my question is what the source of this noise is. Is it a natural limitation of my lens? Too little light available? Is it due to the 640 ISO? Is it due to me or some setting I'm overlooking?

Answer

I think that image is somewhat underexposed and that's half the problem. You might do better to use a higher ISO, and move the histogram to the right. Most of that image is in the lower half of the histogram.

I've read assertions that multiples of the base ISO, so 200, 400, 800 and so on are less noisy than intermediate values like 320 or 640. I don't know if that's true or not, perhaps a myth.

Even with a a camera like the D7000, dark areas are going to contain some noise, even between 400 and 800, especially if you try to lighten them in post processing.

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What causes auto-focus “freezing”?

Question

On occasion, the auto-focus system in my camera and/or lens just stops working. I'll be holding down the shutter release halfway and tracking a subject and I can feel/hear the auto-focus system making adjustments, and then it just stops. If I release the button and try to re-activate, nothing happens. Essentially, auto-focus is dead until I turn the camera off, and then turn it back on again.

I am using a Nikon D90 with a Sigma 70-200mm F2.8. Is the problem likely to be in the camera or the lens? I also have a Nikon 18-105mm lens, but don't use it enough that I can recall experiencing the same problem. I have taken over 10,000 shots with the D90/Sigma combo, and have had this problem occur 10-15 times.

There might be a correlation with how long I've been shooting. Often I will be at an event where I might shoot 500-800 shots in a day of shooting (say 6-8 hours), and it seems like maybe this happens more often later in the day than earlier.

Both the camera and lens are still under warranty, but I'm not sure whether it is the camera or the lens, and don't want Nikon and Sigma pointing fingers at each other, and don't know who to contact first.

Has anybody experienced a similar problem? or have any suggestions on a course of action?

Answer

Everything I've read in the past and a quick Google indicates it's been known to happen with some specific Sigma lenses, yours in particular. But it's nothing more than anecdotal.

If it only happens with that lens and internet anecdotes suggest it's the lens, send the lens in under warranty while you still can.

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