Faulty camera? Faulty lens?

Marcel

Marcel

Kim Jong Bod
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Marcel
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No, before you say "Faulty owner", it's not true :D

Anyway, I'm on my second 350d, and taking some shots today, I've noticed a horizontal banding on it.
Now I've done some googling and apparently this was prevalent on the 10D.

I can't seem to recreate it. I think all the shots I can see it, have been shot at ISO400, instead of anything quicker.

I've uploaded an example ot my domain
banding.jpg


That image was taken portrait mode, and that banding is from the right hand side of the shot, which would make it the very bottom most bit when turned landscape (or normal to you and me).

Ive just looked at some shots taken with last weeks' 350, it seems it's in *some* shots. So if it's a faulty camera, what are the odds of getting two on the trot...lol

So if it's not the camera, is it the lens? Or is it my skylight filter (hoya 58mm).
If it's the lens or the filter, why is it in a pefectly straight line.

Should I be going back into Jessops and asking for a replacement?

Regards

Edit : WRT the ISO thing, and the seeming coincidence between ISO400 and this banding.
I've just taken a lods of shots at ISO400 up to 1600, and I can't seem to recreate this banding, not consistently though.
 
I'm sure I've read about this exact problem elsewhere and someone eventually found the answer several months after originally posting...

It was the filter!
I don't know how expensive your filter is, but apparently it is to do with the quality of the coatings on the filter.

It may be difficultto find the appropriate thread but I'll have a go tonight.
In the meantime, take the filter off and see how it goes.
 
Thanks very much Bachs, I was kinda hoping it was the filter.

For the record it's a Hoya 58mm Skylight, the 9.97 one from Dixons.
I've had a look at some of my very very first shots from the first few hours of owning the camera (pre-filter), and I can't see any banding there. I'll do some more test shots today, with and without filter, see if I can recreate it.

Regards
 
Very odd! I would have thought this was shutter related. With a focal plane shutter, faster shutter speeds are achieved by the second curtain starting to move just after the first one. In other words, instead of the whole sensor being exposed at one time, the two curtains travelling together form a slit - the faster the shutter speed the narrower the slit. It's possible to get freak shots very occasionally due to moving objects keeping pace with the moving slit and appearing elongated in the shot.
 
Bear in mind CT, that this is my second 350D, and looking through my shots, it's apparent on both.

The only two things consistent (apart from the battery and strap of course), are the lens and the filter, those being used on both cameras.
Surely it's more than a coincidence that both cameras / shutters suffer from the same problem?

I wouldn't say they're freak shots. When I first noticed it last night while going through all my shots, sorting, organising, and adjusting exposures etc before converting into JPEG, I started copying some of the worse ones to a folder to burn to CD should I have needed to return the camera to the shop as faulty. Thats when I started checking the shots from the first camera, and noticed the banding there too.
The upshot was I've got about 30 shots put to one side, and I left out quite a few.

It does seem to be more prevalent on the darker shots, or where I've underexposed slightly, and dragged the levels back up in RSE. I do notice it on the RAW files though too, either viewing them through RSE, CS2, or Breezebrowser, so that rules out the RAW converter.

Regards
 
I'm not saying it IS the shutter Bod, in fact Bachs could be right and it's the skylight filter, I'm just damned if I can see how a circular filter would produce linear banding like that.

You can rule out the shutter by taking some slow shutter shots - say 1/60th sec or slower, where the second curtain wont start moving till the first one has travelled right across the sensor. If you still get it with the slower shutter speeds then it's something else - possibly something with the in-camera processing? The other thing to check is - do you get the visible banding when you preview pics on the camera screen- zoomed in if necessary? If you don't, then I'd start to suspect your PC processing software.
 
I tried to take some shots last night at longer shutter speeds (up to a few seconds) and at higher ISO's (up to 1600), and neither reproduced the banding.

I agree with you, I know I'm a bit technically inept at all this :D (Infact I am very much the n00b). I don't understand how something round can produce something so straight, if that makes sense. That's why I immediately pointed the finger at the camera being faulty.

I did try zooming in on some shots on the LCD last night and couldn't spot it. But I can't seem to find the right settings to recreate it at its strongest (or most prominent). Once I've figured out which settings make it worse, then I suppose it will be easier to spot if it's on the LCD or not.

Cameras, don't you just love em?

/goes hunting for his disposable 35mm :D
 
It's bloody annoying mate when you've forked out that kind of dosh. My first 20D was fine for a few hours then just stopped working apart from displaying an 'error 99' message on the screen, and it wasn't reading any CF cards at all. I did get the camera exchanged without any probs, but they can be, and are, faulty sometimes.

Your skylight filter is doing nothing for your pics at all btw - the multi coating on your lens is already corrected for that. Lots of people keep a skylight/UV filter on the lens purely for protection and it's no bad thing, but if i were you I'd leave it oiff for a few days to see if it solves the problem. If it doesn't then the problem is elsewhere.

Good luck with it.
 
Thanks, I suppose I could brave it without the filter. It is only the kit lens. Not some expensive L glass. :D

I'm off out for a little drive with the family this afternoon so I'll be taking some shots, for sure :)

Regards
 
CT said:
Very odd! I would have thought this was shutter related. With a focal plane shutter, faster shutter speeds are achieved by the second curtain starting to move just after the first one. In other words, instead of the whole sensor being exposed at one time, the two curtains travelling together form a slit - the faster the shutter speed the narrower the slit. It's possible to get freak shots very occasionally due to moving objects keeping pace with the moving slit and appearing elongated in the shot.
Click to expand...
Erm... forgive my ignorance on this... are you refering to mechanical curtains?... surely a digital SLR only has a mirror which flips up (my 350 does)... unlike film the sensor shouldn't start recording 'till this has happened... then the mirror pops back into place.
To me it does sound like the coating on the skylight filter interfering with the way the sensor sees things, but it's damn easy to rule it out :)
 
Hedgehog said:
Erm... forgive my ignorance on this... are you refering to mechanical curtains?... surely a digital SLR only has a mirror which flips up (my 350 does)... unlike film the sensor shouldn't start recording 'till this has happened... then the mirror pops back into place.
To me it does sound like the coating on the skylight filter interfering with the way the sensor sees things, but it's damn easy to rule it out :)
Click to expand...

Hell no! Essentially a digital SLR is no different to a film SLR in this respect. As the mirror flips up out of the way, the shutter (behind it) opens and closes, the mirror returns to it's normal position. If you remove the lens and fire the camera with a longish shutter speed you'll see all this happening if you look through the lens opening.
 
CT said:
Hell no! Essentially a digital SLR is no different to a film SLR in this respect. As the mirror flips up out of the way, the shutter (behind it) opens and closes, the mirror returns to it's normal position. If you remove the lens and fire the camera with a longish shutter speed you'll see all this happening if you look through the lens opening.
Click to expand...

I am never ever ever ever ever taking my lens off again.
Well, I will, but only in a biologically and chemically sterile clean room ;)
 
Bod said:
I am never ever ever ever ever taking my lens off again.
Well, I will, but only in a biologically and chemically sterile clean room ;)
Click to expand...

:LOL:

Here you go hedgehog... for film, substitue sensor - the principle is the same.
camera-diagram4.gif
 
Ahhh... cheers, I was looking for one of those refering to DSLR's... I thought mirror lock-up was the same as sensor cleaning, but cleaning shifts the shutter as well. Guess I've been hanging around compacts too long.
 
I've tried unsuccessfully to find the old thread tonight, it was a by the way comment that started it on an unrelated thread.

THe symptoms you see on the image you posted were identical so my money is still on the filter, especially with it being a cheap one which probably means inferior coating.

Time will tell!
 
Well I went out today and took a number of shots (without filter)
Although mostly nice bright shots, I can't see any banding at all, so I think it could definately have been the filter.

I'll keep it off for the time being, and keep a sharp eye on things (pun intended).

Thanks for the replies.
 
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