I think I've posted about this before, and if so, my apologies.

I admit that I am, more than a little, paranoid about electronics that cost alot of money. I tend to worry that "something is wrong".

I recently bought a Canon Digital Rebel XT (just 2 weeks before the XTi, darnit!). I bought the kit, and only have the kit lens. I realize now that this was a mistake. I should've bought the body and a better lens. You know what they say about hindsight.

One thing I've noticed is what I would consider alot of noise in 200 iso or higher. Today we went hiking down the bike path and climbed down to a small stream. On the way there, under tree cover and partly cloudy skies, I took a shot of a log that was cracked and filled with leaves. Attached to this is a crop of that. Am I crazy or is that an insane amount of noise? Of course, the crop was of the full size picture (3456x2304). Specs for shot were:

Shutter: 1/125
Program: Shutter Priority
F-Stop: 5.6
ISO: 200
Focal Length: 55.0mm
No Flash

The noise compensation option was not turned on. Not sure if I should shoot with it on or not (?). Anyways, I guess what I'm wondering is... is the kit lens that crappy? Or is there something wrong? Or is it just me being overly touchy?

Thanks for your patience. :)

is that a 100% crop? ie are we looking at it pixel per pixel?  if so then i would assume that this is close to fairly normal, although i would agree with you (having looked at a shot i took under similar conditions with the same lens but with a 30D body) that the amount of noise is quite a lot.  It shouldnt be the lens that is the problem when it comes to noise.  Take it back to the shop and ask to see a comparson between the cam you have and one out of a box they have to see if it is just your camera or if it is "normal" for that model.

also the noise reduction thing is only really for long exposures and by long it means +1 second.  If you have photoshop then you can use the despeckle filter to get rid of some of the noise (remember to use the unsharp mask after tho - because it degrades the detail), or if you are shooting raw then even better because the EOS utility raw thingy gives you a noise reduction option under preferences :)

Quick question - did you shoot in RAW and convert to JPEG for posting here? Or did you shoot in JPEG mode? Keep in mind that a sensor is like a red/green/blue checkerboard that has to "guess" color differences - especially darker ones where it's only a slightly different hue vs a whole other color altogether. Add to that a JPEG compression (they've gotten much more efficient, but let's face it, it's compressed) and you have strange "noise" that should be a clean surface.

I have a friend with a 20D, and when she shoots in JPEG mode she gets quite a bit of noise in darker areas. When she shoots at ISO400 (which is too often!) it gets pretty noisy in general!

I can tell you that in print ads that would be hidden by the printing pattern (grab ANY publication - especially lower-cost ones, and newsprint - and hold it REALLY close!) so it's not a concern (which is why many magazine articles almost dismiss the noise at those levels until you get up to ISO 1600 where it's significantly "chunky" and won't hide in the printing process), but for inket prints and light-jet type printing it would show up.

If you shot in JPEG mode, try shooting in RAW and convert to TIF (or Bitmap - either is uncompressed) - then look at it in Photoshop (or like app) at 100 percent and see if it's still there.

Good luck-
-Lew ;-)

Hi all,

Just to answer the questions:

• Yes, it's a 100% crop

• I shoot in RAW, and yes it was converted to jpeg in photoshop.. However, if I view the RAW image, there's really no difference that the eye can see (what I mean is, the level of noise is pretty much exactly the same, jpeg compression didn't make it any worse than it already was). Saving it out as Tif (for this particular image) ends up being just about the same

Thanks

-Melen

Bummer!

Well, give this a shot (let's rule something else out, shall we?) - take a succession of bracketed images from clearly overexposed to clearly underexposed, in 1/3rd stop increments of shutter speed while maintaining the same aperture. Get a complete tonal change example. Pick something static like the shot above, and use a tripod. I would actually call that one underexposed - and it's also where noise gets more pronounced.

Underexposure is devastating in video, which is where digital photography got its starting ground, and still shares some like-traits in that respect.

Get them back into Photoshop and see if there's any difference based on exposure.

Good luck!
-Lew ;-)

What version of Photoshop do you own? it may be to do with the profile you have loaded there is a free version of Rawshooter I can recommend the image does look a little underexposed and if you allow Photoshop to correct it you may get more noise.. Try a better lit subjecy first to see if this is a camera problem

BTW  the kit lens is not too good!

Hi Lew and Danny,

Thanks for the responses. I will definatly try that with some bracketed shots. Definatly this shot was underexposed, no doubt about that.

I'm using Photoshop CS2, tho to be honest I don't know what profile I have loaded. Most likely whatever was installed by default. I have to confess that I start getting confused when it comes to the profiles, so I doubt I've ever changed it.

I hear you on the kit lens. I'm really disappointed that I didn't buy the body and a seperate good lens. The purchase was somewhat spontaneous (and I always get myself into trouble buying things that way)! In good light it can produce some amazing photos tho.

Thanks!

-Melen

OK check out this link http://photoshopnews.com/category/photoshop-news/camera-raw/

 

Thanks Danny. The beta plugin works well, tho it doesn't help the noise (actually seems to make the noise more monochrome).

I think that this particular problem may just be that it's underexposed.

But it begs the question... Is this the type of noise I can expect when doing night shots as well? I've seen some suprisingly clean night time shots with the XT and the kit lens.

Thanks!

-Melen

Shouldn't be the lens when it comes to noise - it's how the camera's circuitry in processing color information based on exposure. The camera may just not handle underexposure really well.

-Lew

How much exposure did you add (if any) because if you need to add 3 stops, you introduce noise.

yeah it is more to do with the underexposure if you exposures are going to longer you can turn on noise reduction in the camera and lower the ISO and use a tripod

Thank you all for the suggestions. I guess I was just being silly. The shot was very underexposed, and I didn't do any compensations, I simply raised the brightness in Canons apps before saving it out as a TIF.

Still very early in the learning phases, and I find it awesome that all of you are so patient. Thanks again. :)

-Melen

Quote - I simply raised the brightness in Canons apps before saving it out as a TIF.

By how much? If you needed to raise the brightness quite alot then your image was underexposed. This would show the noise.

May I add my 2 cents worth, FWIW? Film grain I can put up with, and even find it attractive in some cases; but I must admit I find digital image noise VERY ugly and annoying. Of the cameras I've owned (not being overloaded with money), the absolute worst was a Trust 910Z. The images it produced at 200 iso & above were completely unusable, and those at 100 weren't that inspiring either. A Kodak 3.1 MP (I forget the model) went too far in the opposite direction, producing grass that looked like a snooker table, and painted hair. I now have a Panasonic Lumix FZ7, which is great, but also produces awful noisy images at 400 iso in available light (though flash seems OK). Maybe I've been unlucky, but I now consider some sort of NR software indispensable. The upshot is that I have tried a lot of NR apps, and have settled on Imagenomic's Noiseware Pro plugin. With a bit of tweaking, it can remove all noise without loosing too much detail (see image). You may prefer something else, but it costs nothing to give 'em a try. Most have some sort of free demo. Hope this helps. Best, Cal

That is fantastic! I'm definitely going to look into that - thanks for the pointer Cal.Amari (LOL - that happens to be my favorite appetizer - great name!)!
-Lew ;-)

Thanks for that suggestion, Cal.Amari... Wow! That software does an amazing job! I've been using Noise Ninja, but I have to say that it didn't clean that image up quite that good. I will have to give Noiseware Pro a try.

-Melen