Noise in Photomatix

[erics500d]

Hey!

I think my pictures got a lot of noise when I combine them in Photomatix. I captured them at ISO 100, so I can't understand why!
Please help me on this

Regards, Erik

[chris-p]

Hi Erik

Need more info, sorry!

What sort of pictures are you combining (JPEG or RAW)?
How many exposures did you make (lots of shots, or one RAW file that you adjust)?
What ISO did you shoot at?
What camera have you used?
What was your shutter speed?

HDR doesn't usually increase noise but it may make it more obvious in certain areas depending on the ISO setting and contrast range.
DRI on the other hand makes noise much much worse as you magnify it by overlaying it.

[silversnapper1]

Have you tried using the noise reduction facility in 'Utilities'?

[erics500d]

Hi Chris!

I'm combining raw files.
I think it was 6-7 exposures I combined.
I shot at my lowest ISO setting, 100.
I used a Canon EOS 500D.
My shutter speeds was from about 1/40 sec to 5 sec I think, so they weren't long in my opinion.



Silvesnapper: Can I find this noise reduction in Photomatix? And does it work good?

[chris-p]

Sounds like you're doing everything as right as you can. Can you upload an example?

[silversnapper1]

Yes, it is in the 'Utilities' in the toolbar.

[erics500d]

Well, I don't have any hdr's on my pc now, but I'll try to make a new hdr, and use silversnappers tips.

[erics500d]

I used your tips and now there's much less noise in my hdr's! Thank you!

But I just want to ask you about one thing while I'm writing; is it normal that the hdr's aren't *** sharp as "normal" images and are there any way to prevent too much chromatic aberration? Give me some tips regarding these questions!

Regards, Eric

[chris-p]

It's very common that HDRs aren't as sharp. This usually comes from the fact that software like Photomatix will try to correct for movement between shots, either of the camera or in the frame and so you often loose fine definition on the edges of things.

You can minimise this by making sure there is as little movement as possible between your shots. If there really isn't very much movement, you could try turning off the alignment steps and dealing with any errors later on in Photoshop.

With regards to chromatic aberration, it's a feature of the lens rather than anything else. However, when you increase the colour and tonal range of the shots it includes any CA. There are loads of ways of removing CA from pictures. An easy method is to use a Hue/Saturation layer and the eyedropper tool in Photoshop. Select the colour of the CA and just desaturate it.
The only time this is problematic is if you have a lot in the frame thats very similar colour. For me, thats pretty rare.