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View Full Version : Nikon D80 and straight and curved edges



woodpigeon
06-25-2007, 02:01 PM
Dear Sir,

I have a four week old Nikon D80 that has an 18-70mm lens.

Can someone tell me why, in my photographs, straight edges of walls, roofs, boxes, telegraph poles, venetian blind slats, etc, are saw toothed?

Other edges, ie curved edges, are slightly wavy, or rippley.

Thin narrow objects, like garden canes, or rods, look like barber's poles - dark strip,light strip,dark strip,light strip.

I have read Ken Rockwell's D80 User's Guide and have changed this and that and the other in the various Menus and the problem persists.

Yours sincerely, woodpigeon

jcon
06-25-2007, 02:10 PM
I just woke up so I wont be able to explain in detail(yea I know its 3pm here but im sick,lol), so I will jsut give you a simple explinations. Its the lens. What youre seeing is barrel distortion, color moire, etc...

So dont think its the Nikon D80, its not.

Also, posting examples helps alot too.

Sambru
06-25-2007, 03:08 PM
I have the exact same setup - D80 with 18-70 glass and I have no problems as you mentioned.

woodpigeon
06-25-2007, 04:00 PM
Thank you jcon and Sambru.

I would have included an example piccie but this is my first posting to DCRP and I haven't worked out how to do it. It's late and I'm off to bed. The next two or three days will be busy days but when I have the time I will send one.

This lens is brand new so I shall return it and ask for an exchange.

Many thanks.

Yours sincerely, woodpigeon.

rawpaw18
06-25-2007, 04:26 PM
If you exchange it for another 18-70, the distortion will still exist. It is amplified when shooting at an upwards angle. Make attempts to shoot not as wide if you are shooting straight lines such as buildings and keep straight lines toward the middle of the frame to help keep it under control.

Sambru, the picture you have posted has the structure in the middle of the frame and was shot at 240mm, so the distortion from the 18-70, which is very noticeable, but not that noticeable that it shows up when you use your 70-300 lens:D

Just realized I did not get your joke, you got me.

Classic96
06-25-2007, 08:41 PM
It could also very well be your photo viewing/editing program. I use Photoshop Elements 5.0 and shoot a D50 on RAW. When I am editing my files, for some reason PSE 5.0 shows the files in a very rough format UNLESS I am viewing the file at 100% size or greater. I haven't been able to figure out why it does it, but if I view the file anywhere else it looks normal.

K1W1
06-25-2007, 09:43 PM
Can someone tell me why, in my photographs, straight edges of walls, roofs, boxes, telegraph poles, venetian blind slats, etc, are saw toothed?

Other edges, ie curved edges, are slightly wavy, or rippley.

This problem is nothing to do with the camera or the lens

Saw toothed straight lines and rippley curves are a function of you viewing images at very low resolutions.
What program are you using to view the images, what screen resolution are you using and what are the camera settings you are using (jpeg fine, jpeg normal, etc)?

Your problem is either your computer software, your computer screen resolution or the fact that you are using the lowest resolution jpeg setting to take the photos in the first place

rawpaw18
06-26-2007, 04:21 AM
After reading K1W1's post,

I missed entirely the saw toothed part of your post, which of course was the purpose for you posting your question. The 18-70 is known for its barrel distortion, and you were mentioning about problems with lines that is why I immediately thought distortion.
Make some other changes as per K1W1 suggestions to see if your problem clears up.

XaiLo
06-26-2007, 10:48 AM
If you exchange it for another 18-70, the distortion will still exist. It is amplified when shooting at an upwards angle. Make attempts to shoot not as wide if you are shooting straight lines such as buildings and keep straight lines toward the middle of the frame to help keep it under control.

Sambru, the picture you have posted has the structure in the middle of the frame and was shot at 240mm, so the distortion from the 18-70, which is very noticeable, but not that noticeable that it shows up when you use your 70-300 lens:D

Just realized I did not get your joke, you got me.


lol, this must be the slow time of the month, I just got what you were refering to rawpaw18. lol

woodpigeon
06-27-2007, 04:46 PM
Good evening everyone,

I have had second thoughts and not returned the lens and asked for a new one. From what you have told me it seems unlikely that I would be able to convince a salesman that the lens is at fault. I am not confident that I could do that.

In reply to K1W1 -

I use Adobe Photoshop Elements 4 to view my images.

Screen resolution is 1024 x 768 pixels.

Colour is set at Highest [32 bit] on a Radeon 9200SE monitor.

DPI setting is normal size [96 DPI].

Scan refresh rate is 75 Hertz.

I have played around with jpeg fine and jpeg normal and jpeg basic in Auto Mode and P mode.

Yesterday, I was advised to view a distorted picture with the Windows Picture and FaxViewer in ‘open with’. I was told that if I do and the picture looks better than it does when it is viewed with APE4, it is likely that Adobe is the cause of the trouble. So I did, and lo and behold the picture was near perfect. I looked at other distorted pictures with Windows Picture and Fax Viewer and again, each was near perfect. There was slight distortion and the images are not up to Nikon standard.

So, is Adobe the likely cause of the distortion and if it is how do I get rid of Adobe distortion?

Adobe is reputed to be the world’s best digital image editing programme. If that is true, must I buy the UKŁ55 Elements 5 upgrade, or the ultimate Adobe Photoshop Professional programme Adobe at much greater expense, to correct distortion that Adobe has created. I have been told that no other programme can do it so well.

Sorry, I haven't cracked how to 'manage attachments'.

Yours sincerely, woodpigeon

K1W1
06-27-2007, 05:12 PM
What camera settings are you using (RAW. jpeg fine, jpeg normal, etc)?

I assume that you are probably shooting in jpeg. If that is the case there are plenty of options for you for software.

The very first thing you should do is download Irfanview from here (http://www.irfanview.com). It's free and should be pn every photographers PC. It will allow you to view resize rotate create slide shows and do all sorts of things.
For image editing of jpegs there are plenty of options (and plenty of threads if you have a look back in the forum) that are inexpensive or free.
Picassa is free and a reasonable place to start.
Gimp is free.
Other people can offer other solutions to you.

Lastly. What do the pictures look like when printed on paper?

woodpigeon
06-27-2007, 05:49 PM
Dear K1W1,

Many thanks. It is beginning to dawn on me that distortion is something that I will have to live with, no matter how good my camera is.

I'm a jpeg man and I haven't got a photo printer so I do not know what my printed images look like. I'm very new to digital photography so a printer is one of my 'wants'. I am a village 'local historian' and the camera will take images of buildings etc that will will be archived on disc.

I'm grateful for the advice, from everyone.

Best wishes. woodpigeon

K1W1
06-27-2007, 06:58 PM
If you shoot jpeg just take a memory card with some images to the local photo processing place wherever that may be and get a couple of prints made.
It will cost virtually nothing and at least let you know what things look lile on paper (I'm picking they will have nice smooth edges).
What do you mean by distortion? Do you mean the jagged edges you initially asked about or do you mean where the angles don't look correct and building walls look like they curve or slope?

woodpigeon
06-28-2007, 05:30 AM
Dear K1W1,

I use 'distortion' as a blanket term for sawtooth edges of reeds, rippley horizontal lines, barber's pole and barley sugar horizontal tubes or rods. I have seen concave and convex edges of downcomer drain pipes and the undersides of gutterings but it is very slight.

I have downloaded Irfanview and yesterday, someone who occasionally looks over my shoulder when I write to you, bought for me without being asked, the Anniversary Edition of the Microsft Digital Image Suite.

I am going to take a series of different jpeg images with different settings and see what the results are like. It is too easy to forget what one has done and opening each image's 'show properties' is time consuming.

I will take some dissatisfactory images on a memory card to a photo processor and see what the prints are like.

Best wishes and thank you.

Yours sincerely, woodpigeon.

fionndruinne
06-30-2007, 12:22 PM
Those of us who are gamers (or closet gamers at least) know well that jaggy-edge problem, it's called aliasing. And yes, it is usually the fault of low image quality. What are your image quality settings in-camera? Are the photos showing up with this problem on the camera LCD (because, with my D40 at least, maximum magnification in playback actually blows an image up to larger than its actual size, causing some aliasing/pixelating), on your computer (the photo display software may introduce some problems like these in displaying an image because it resizes it to fit the viewing area), or on the internet (because most photo hosting sites automatically decrease the quality of the image when it's uploaded)?

woodpigeon
07-01-2007, 10:17 AM
Thank you everyone for your interest and advice.

I think that I may have solved the ‘distortion problem’. I began by drawing a chart that has many columns for settings that I can change.

JPEG Fine, Normal, or Basic
Mode Auto, or P, S, A, M.
Image Size Large, Medium, Small.
Exposure Compensation 0.7 to + 5.0
ISO Auto On or 0ff.
ISO Sensitivity up to 1600
Optimize Image Normal to Portrait.
Optimize Image Custom settings locked with DONE
Image Sharpen Auto to High
Tone Normal to More
Colour mode Ia to IIIa
Saturation Auto to Enhanced
Hue – will not touch it

After more than twenty tests with different setting configurations my images definitely do not have much ‘distortion’.

The configuration that gives decent results is -

JPEG Fine
P – Programme Auto Exposure
Image Size Small
Exposure Compensation 1.0
ISO Auto Off
ISO Sensitivity 1250
Optimize Image Normal
Optimize Image Custom
Image Sharpen Auto
Tone Normal
Colour Mode IIIa
Saturation Normal
Hue – Haven’t touched it.

Someone may ask why have I done this or done that. Some of the settings perhaps are or seem to be rediculous or unnecessary. I can only say that I have experimented and have found a formula that seems to work and the ugly distortion has all but disappeared. I am a complete novice who has always ‘pointed and shot’ and I am NOT saying that I am right. I want to learn, so if there are constructive criticisms out there, fire away.

Best wishes to everyone. woodpigeon

Sambru
07-01-2007, 10:14 PM
If you exchange it for another 18-70, the distortion will still exist. It is amplified when shooting at an upwards angle. Make attempts to shoot not as wide if you are shooting straight lines such as buildings and keep straight lines toward the middle of the frame to help keep it under control.

Sambru, the picture you have posted has the structure in the middle of the frame and was shot at 240mm, so the distortion from the 18-70, which is very noticeable, but not that noticeable that it shows up when you use your 70-300 lens:D

Just realized I did not get your joke, you got me.

Sorry, I didn't mean to mislead anyone posted the wrong photo ...sorry about that I am new to all this as well, however my 18-70 Nikkor work really well I will try to post a photo with it. Attached is a photo of the cement forms of the house I am building.

rawpaw18
07-02-2007, 04:35 AM
It was just my lame attempt at humor, I was not trying to through you
under the bus.
It took xailo a little while to get the joke too. Keep posting, at least the
walls of your new house are not distorted:)

Ray Schnoor
07-02-2007, 06:01 AM
After more than twenty tests with different setting configurations my images definitely do not have much ‘distortion’.

The configuration that gives decent results is -

JPEG Fine
P – Programme Auto Exposure
Image Size Small
Exposure Compensation 1.0
ISO Auto Off
ISO Sensitivity 1250...

Someone may ask why have I done this or done that. Some of the settings perhaps are or seem to be rediculous or unnecessary. I can only say that I have experimented and have found a formula that seems to work and the ugly distortion has all but disappeared. I am a complete novice who has always ‘pointed and shot’ and I am NOT saying that I am right. I want to learn, so if there are constructive criticisms out there, fire away.

Best wishes to everyone. woodpigeon
If at any time in the future you are planning to print the images, I would suggest against saving images with "Image Size Small". The camera would be downsampling your 10MP image to a 2.5MP image, in effect throwing away 75 percent of the detail in the picture. It sounds as if your software just isn't viewing the 10MP picture correctly. Try Irfanview as K1W1 suggested. If you want to view the 2.5MP picture in your software, keep the "Image Size Large" and resize the file to a 2.5MP picture afterwards. It may also help if you posted some of your photos showing the sawtooth/no sawtooth. You should also use the lowest possible ISO that you can. Image quality will deteriorate as you increase ISO. The D80 may be good at high ISO, but an ISO 100 photo will be better than an ISO 1250 photo if you have enough light.

Ray.

K1W1
07-02-2007, 06:31 AM
I agree. Image size small is an absolute no no unless you are only taking photos to display at 640 x 480 on the web or something.
Image size small will be one of the primary reasons for your jagged edges when you try to view at anything like full resolution.

Exposure 1
ISO 1250

is going to give you very bright images any any sort of normal light and will start to introduce noise in the images (you won't see that with image size small but you sure will with larger images where the details start to appear).

Rooz
07-02-2007, 06:54 AM
can i just add that for whatever reason when using CS2 i notice alot of jaggies on screen aswell, (i don;t notice it in any other software), but they dont come out when printed or when viewed in another application.

if anyone can tell me why that would be appreciated. :)

K1W1
07-02-2007, 07:19 AM
Don't use CS2 that much and I can't say I've ever noticed jaggles.
Do you have a LCD or CRT monitor? If it's LCD are you using the native screen resolution? LCD's do not like running at anything other than their native resolution.

humbertklyka
07-03-2007, 02:56 AM
It seems like photoshop is using nearest neighbour interpolation when rescaling the image to fit the screen (fastest but ugliest method), but the simple way of checking if its the camera or the or the viewing program, just make sure to look at the image at 100% magnification in the program, so that no scaling takes place. If there are still jaggies around, then it would seem that the low pass filter in the camera doesnt work as intended.

/humbert

coldrain
07-03-2007, 04:48 AM
can i just add that for whatever reason when using CS2 i notice alot of jaggies on screen aswell, (i don;t notice it in any other software), but they dont come out when printed or when viewed in another application.

if anyone can tell me why that would be appreciated. :)
When you view a picture at for instance 16% or whatever, you will see jagged lines. This is because PS uses a very fast scaling algorithm for it (just leaving lines out, basically).
However, when you scale the photo, it uses high quality algorythms, making the results not jaggy at all (combining information of more than one line to for the scaled down new lines).

So... the reason is that PS uses its own, very fast, algorithm. Other programs maybe use the OS's own algorithm (actually scaling down the pic for screen purposes), making for "smoother" results than PS when you don't view at 100%.

Rooz
07-03-2007, 05:02 AM
When you view a picture at for instance 16% or whatever, you will see jagged lines. This is because PS uses a very fast scaling algorithm for it (just leaving lines out, basically).
However, when you scale the photo, it uses high quality algorythms, making the results not jaggy at all (combining information of more than one line to for the scaled down new lines).

So... the reason is that PS uses its own, very fast, algorithm. Other programs maybe use the OS's own algorithm (actually scaling down the pic for screen purposes), making for "smoother" results than PS when you don't view at 100%.

aha...that makes sense. thanks

Rooz
07-03-2007, 05:03 AM
It seems like photoshop is using nearest neighbour interpolation when rescaling the image to fit the screen (fastest but ugliest method), but the simple way of checking if its the camera or the or the viewing program, just make sure to look at the image at 100% magnification in the program, so that no scaling takes place. If there are still jaggies around, then it would seem that the low pass filter in the camera doesnt work as intended.

/humbert

i;m sure this is correct aswell but it was a little too advanced for me so i have absolutely no clue what you just said. thats though. :)

SpecialK
07-03-2007, 07:30 PM
For the original poster:

To upload an image...
Resize a copy to about 800-900 pixels in the longest dimension. Save it where you can find it easily (don't "Save for web" which wipes out all the exif info). In "manage attachments", click "browse" and navigate to the image file. Double click the file name. Click "upload". Do that for up to 10 images you want to post. Then in the text box, type what you want to say. Put the cursor where you want to insert an image. Above the text box is an icon of a paperclip. Click the arrowhead to the right of it to display the files you have upoaded. Click on the file you want to put in the text box at the cursor location. Repeat as necessary.

Part of going digital for me is getting rid of paper copies, so I do very little printing. I do on occasion print a 4x6 or even a couple images on a 4x8 using this neat little printer:
http://www.amazon.com/Canon-Selphy-CP400-Photo-Printer/dp/B0007KQT1W/ref=sr_1_1/102-0056599-9306501?ie=UTF8&s=electronics&qid=1183512523&sr=1-1