Photoshop help, please!

I've posted this in here, if I'm in the wrong place, feel free to move it.

I've taken this long exposure, but it is very grainy. How can I get rid of the grainy-ness, without losing detail?
Also, what would cause this? It was a 30 second exposure on ISO200.

[IMG]http://i75.photobucket.com/albums/i296/Father_Ted/PHOTOS/OrionNebula.jpg[/IMG]

Thanks guys.

I think this may be more to do with the camera you are using which was one of the first DSLR's and is not as good on the noise front as the more recent Pentax models. This shot would be almost noise-free with a K-x, K-r or K-5. I'm not sure what advice I can give you on getting rid of the noise, but it's always best if you can avoid it in the first instance.

Regards
David

Yeah, I know what you are saying, but I don't have the budget to get a new camera...only wish I did

Any chance that it's partly caused by light pollution? Maybe there's a plug-in available to fix this for you.

D'you know? I hadn't considered light pollution!
I live in a very (light) polluted area. Now that I've proven I can image the nebula with my scope, I'll take it to a darker area and try.

Now why didn't I think of that

Hi Ted, sorry if I came across a bit sharp with the previous post, I understand that you may not be able to get a newer camera, but I was just being open about what may be causing the noise. I have a K-m and a K-x, only about a year apart in age, but you would be amazed how much less noise is on the K-x images. I can't use the K-m at more than about 400 ISO without getting loads of noise, but the K-x is almost noise free at 1250 ISO. If you could save up a bit I'm sure you would be well rewarded.

Regards
David

Just a quick thought, have you got the noise reduction setting turned on (in C Custom Settings menu?)

John

I have run your photo through Topaz Denoise 5. It gets rid of all the noise and banding.

Hi Ted

Just had a quick look to see what LR3 could do for the noise and light pollution.

Here's the result




Certainly an improvement

Carl

OK..so it is possible, just CS2 won't do it.
I've been lent a copy of lightroom to try out....I'll put that on my machine this weekend.

Thanks very much guys!

The *ist-DL has a CCD sensor. They get hot during long exposures!
Additionally, I found that the quality of the battery made a big difference. Some of the batteries I used in my *ist-D were getting warm during long exposures, and the heat in the battery created more image noise

For asto work you are probably better off taking many shorter exposures and stacking them (Google for freebie stuff).

The image you show has 'banding noise' - the regular lines, and general noise. CS2 can tackle it, but LR is easier and perhaps more intuitive for noise reduction.

Was the JPG you showed processed from RAW? Did you have to 'push' up the exposure in the RAW converter?

Hope that helps!
Matt

It was processed from RAW. I had to up the exposure a little, but not overly.
I hadn't thought of heat, although, that night, if the sensor was warm, then it was the only thing getting warm!

As I mentioned, the batteries getting warm are the number one thing to check. The CCD takes a heft of current to run, and doing this for a substantial time will create heat in the batteries.

I'd suggest doing a test run indoors. When my (dud) batteries ran they were significantly warmer than body temperature - and all that heat translates into electronics supply noise that eventually finds its way into the sensor circuitry.

Matt

Sorry to sound at odds, but 30secs doesn't sound like long enough to cause heat problems to me.

Admittedly I have a K10D, not a *1stDL, but this also has a CCD sensor and I've run exposures of some 10mins trying out welding glass (circa 10 stop) high density filters.

I have had "smudging", if I can call it that, due to light pollution, in particular by not blanking out the eyepiece during the exposure

Bernard

I find very few of my images, when looked at closely enough, that wouldn't benefit from some degree of 'De-Noiseing', although it is never a uniform amount needed across the whole photo. For that reason the software used needs a fair amount of selective and fine control, so you can put the emphasis onto, say, the shadow areas or yellow colour noise etc.

I think this is true regardless of the camera, sensor, or subject matter. So a good flexible software solution that can deal with all situations is a good thing to have. The Topaz product was mentioned above, and its what I use as first choice. It has the fine control and selective targeting required, but for me at least, it is the most economic option as I don't use lightroom.

I run the Topaz plugin through Photoshop Elements 8, its a 64bit version, and great value. It can 'plug-in' to the full photoshop as well. I don't think you need lightroom just for 'de-noiseing'.