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DPChallenge Forums >> Hardware and Software >> smudged looking image - does anyone know why?
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 10/04/2008 07:00:42 AM · #1
i've been noticing a very smudged look on a lot of my photographs ..
i especially notice it on extreme close-up work ..
camera - Canon EOS-40D
the lens - Canon EF 100mm f/2.8 USM Macro ..

this photograph should give you an idea of what i'm talking about ..
its a small clover flower .. the fly/insect would be about 1/8" or 3-4mm long ..
used Extension Tube EF12II on this shot, but i've noticed the smudged look when not using it.


camera settings .. 1/125sec at f5.6 & iso100 .. speedlite 580EXII fired ..
the area of concern is where the green blends into the brown .. its not a smooth transition ..
imagine a new layer and using a brush at 20% opacity in dissolve blending mode .. well, it almost has that appearance ..
the flower isnt sharp and looks 'dirty' as well ..

i've had my camera sensor cleaned twice in the last month by canon ..
i have a BenQ LCD monitor 22" which is less than a year old .. i recently recalibrated it using adobe gamma and also used this site photo friday monitor calibration tool
i'm not sure if the monitor could be my problem .. there is an adjustment for sharpness on the monitor which is set at medium ..

if anyone has any idea i'd be very grateful to hear back ..
thankyou .. :)

10/04/2008 07:21:20 AM · #2
Test to see how clean your sensor really is. Put a completely FFFFFF white screen on your computer. Using either a 50mm or the 100mm lens on manual focus, photograph the white screen with a small aperture (f/29 f/22 say) at a slow shutter speed overexposed. Make sure the screen is not in focus. Get the JPEG or RAW file into Photoshop and apply autolevels. Every sensor spot will show up. Perhaps you will find the sensor is dirtier than you expect.

Some people use a lot of cleaning fluid when cleaning a sensor and that tends to leave dirty streaks.

I advise you to learn to clean your own sensor. It's not rocket science and if you follow directions, you can do a better job than you local Canon contractors (who are not even Canon people really but are bushwhackers that Canon has hired from some sheep shearing job off season ;-) Buy some Visible Dust sensor swabs and some Eclipse fluid. The Visible Dust swabs work very well, in my experience (better than Sensor Swabs). They are, in the USA, about USD39.95 for 12 swabs. Expensive, but they work well. I bet so-called Canon cleaning is more expensive.

Cleaning ones own sensor is the way to go. I know you can do it.

10/04/2008 07:32:14 AM · #3
thanx so much andrew ..
i've been wanting to clean the sensor myself for a while now .. read how in various sites and then hit a brick wall when i tried to find a supplier ..
& the reason i had my sensor cleaned twice in a month is because i wasnt happy with their first clean .. i took it back and they did another one free .. but as you say, just because they do it doesnt mean they'll do it perfectly ..
which really is pretty shitty .. !!
i'll do the white screen test and see how the sensor looks .. :)..


10/04/2008 07:39:12 AM · #4
Hi Roz, I have left you a comment on your image..... love shez
10/04/2008 08:15:07 AM · #5
i've done the white screen test and this is the result ..
it came out very different for two different exposures ..
both have an auto level action applied ..

spose the proof is in the pudding tho ..
it doesnt look clean to me and it doesnt look like something i've let in when changing my lenses ..
like the 'normal' dust specks ..
i'm wondering if canon have damaged my sensor when they cleaned it .. it looks really bad .. ??

also the smudging in the white screen test examples doesnt correspond to the smudging in the fly shot where the smudging follows where the colours blend from brown into green .. ??


Message edited by author 2008-10-04 08:48:13.
 10/04/2008 08:25:52 AM · #6
Looks like banding to me. Usually happens when you push curves hard and it usually happens in areas of solid colors where there is a gradual transition of similar colors such as a sky. Are these appearing before processing or after? I suppose it could happen in camera if you have a high contrast setting, though I'm not sure about that. I don't feel this is related to a dirty sensor but it could be an indication of something wrong with your camera's sensor if this is occurring on all your pics. Hope that helps Roz
 10/04/2008 08:29:28 AM · #7
If you clean the sensor yourself, make sure you get the correct cleaning fluid for that sensor. You'll need (if your're using the Eclipse product) the E2 fluid, not the regular Eclipse.

A decent source is : The Filter Connection.
 10/04/2008 08:46:28 AM · #8
for info .. the fly shot is totally unprocessed .. just resized for web .. which is why i'm worried about the camera or possibly the lens being the problem creating the smudged and dirty look .. :) ..

10/04/2008 08:46:51 AM · #9
thanx trevor and barry .. :)
 10/04/2008 09:05:37 AM · #10
I'm not sure about the smudging; I'd be more worried about those white arrow-shaped aberrations on your picture.

;-Þ
 10/04/2008 09:09:19 AM · #11
Originally posted by Pug-H:
I'm not sure about the smudging; I'd be more worried about those white arrow-shaped aberrations on your picture.

;-Þ

lol lol LOL .. you're wasted in this thread .. you should be in the new humorous title .. :)
 10/04/2008 09:13:30 AM · #12
I can't see any smudging in that pic. All looks normal on my screens. The bg looks great actually.
 10/04/2008 09:25:47 AM · #13
Originally posted by Jac:
I can't see any smudging in that pic. All looks normal on my screens. The bg looks great actually.

that's weird & confusing .. :)


10/04/2008 09:30:26 AM · #14
Originally posted by roz:
Originally posted by Jac:
I can't see any smudging in that pic. All looks normal on my screens. The bg looks great actually.

that's weird & confusing .. :)


I hesitated before posting for fear I would complicate things. I viewed this on my two monitors and cannot see anything abnormal. Any chance for a full res upload somewhere so we can view it full size?
 10/04/2008 09:32:59 AM · #15
Originally posted by Jac:
Originally posted by roz:
Originally posted by Jac:
I can't see any smudging in that pic. All looks normal on my screens. The bg looks great actually.

that's weird & confusing .. :)


I hesitated before posting for fear I would complicate things. I viewed this on my two monitors and cannot see anything abnormal. Any chance for a full res upload somewhere so we can view it full size?


I have to agree with Jac. Nothing weird here, just a beautiful background bokeh...
 10/04/2008 09:37:35 AM · #16
I just thought I was blind but I can't see anything abnormal either.
 10/04/2008 10:04:39 AM · #17
Ditto. I'm loving what I see in this image. So either you're seeing something full size that we aren't seeing, or else the background blur/bokeh is completely normal and even desirable.
10/04/2008 10:06:14 AM · #18
Originally posted by roz:
Originally posted by Jac:
I can't see any smudging in that pic. All looks normal on my screens. The bg looks great actually.

that's weird & confusing .. :)


Actually it's the EW factor. The sample you posted is not big enough to examine for defects. I believe you can post it much larger in you portfolio and we'd be better able to critically examine it.
 10/04/2008 10:13:50 AM · #19
Video card driver problems? Have you changed anything recently? Do you have access to another card that you can swap? Or better yet, is there another monitor you can view it on nearby?
 10/04/2008 10:24:21 AM · #20
Originally posted by roz:
i've done the white screen test and this is the result ..
it came out very different for two different exposures ..
both have an auto level action applied ..

spose the proof is in the pudding tho ..
it doesnt look clean to me and it doesnt look like something i've let in when changing my lenses ..
like the 'normal' dust specks ..
i'm wondering if canon have damaged my sensor when they cleaned it .. it looks really bad .. ??

Roz, I'm no expert, but it looks to me as if they may have used too much of the cleaning fluid and some has seeped down between the low-pass filter and the camera sensor. I've been wet cleaning my cameras for the last two years and one of the real risks is using too much cleaning fluid.
Try checking for dust on the sensor again but this time, use a normal piece of white printing paper and see if the results are the same.
 10/04/2008 11:05:14 AM · #21
i said earlier that i'd recalibrated my monitor .
i recalibrated it after i put my free study entry on greg gregoryb's computer just to see if it looked different .. the difference in the red was amazing .. what looked bright and dramatic on mine looked totally oversaturated on his .. we both then recalibrated our monitors, which are actually the same brand and type .. even so there were differences in colours .. the computers are in the same room and under the same lights etc ..
i thought i'd got my monitor correct by using adobe gamma and this photo friday monitor calibration tool ..
since starting this thread i've been looking at other ppl's photographs in dpc and have noticed on some pics the same smudging that i can see on my fly
this could mean its a monitor problem .. ???
but after calibrating my monitor and apparently not succeeding in getting it right i'm not sure where to go from here ..
i know there's a device you can buy for HEAPS that you dangle in front of your monitor and it reads it .. i've heard that its brilliant for calibrating your monitor .. but there must be a cheaper way .. ??

a few minutes later .. i typed out all that and then noticed your comments irene IreneM
and jack Jac ..
jack, i havent made any changes to the computer lately but i'll check the video card driver tomorrow ..
also i'm seeing the same smudging on greg's computer altho not quite as bad ..
irene .. i tried to do another dust sensor test but i dont think i'm getting a correct reading with only electric lights .. its night here so i'll do it tomorrow ..

i dont think you'll see the smudging better any larger coz the markings are the same on the resized for web images as before resize .. :)

thankyou so much everyone for your suggestions ..
anymore would be welcome ..
its now 2am here .. i'm going to bed .. hopefully i wont have nightmares about my camera .. !!..:)
i thought it was 1am .. i forgot we change over to daylight savings time tonight .. so i just lost an hour .. :)


Message edited by author 2008-10-04 11:11:53.
 10/04/2008 07:07:02 PM · #22
Not sure what settings you use in camera. Sometime back I switched to "neutral" which means that the camera adds no contrast, sharpening, saturation or anything to the RAW image that I shoot. At least then I know all the errors and splots etc are entirely my fault. Your notes about monitor calibration are interesting.
 10/04/2008 07:27:17 PM · #23
Originally posted by pineapple:
Not sure what settings you use in camera. Sometime back I switched to "neutral" which means that the camera adds no contrast, sharpening, saturation or anything to the RAW image that I shoot. At least then I know all the errors and splots etc are entirely my fault. Your notes about monitor calibration are interesting.


I thought all RAW images were untouched by software? Those settings only alter your jpeg images and not the RAW ones.
 10/04/2008 07:35:12 PM · #24
Originally posted by Jac:
Originally posted by pineapple:
Not sure what settings you use in camera. Sometime back I switched to "neutral" which means that the camera adds no contrast, sharpening, saturation or anything to the RAW image that I shoot. At least then I know all the errors and splots etc are entirely my fault. Your notes about monitor calibration are interesting.


I thought all RAW images were untouched by software? Those settings only alter your jpeg images and not the RAW ones.


True! Sometimes I use the B/W option, so I can see what it looks like; on my LCD-screen it's b/w, but when opening in software it's just the RAW-image without any adjustments.
 10/04/2008 08:29:20 PM · #25
My wrong, I was thinking of the RAW conversion...
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