Spot appearing on long exposure raw images

[malbooth]

Advertisement (gone after registration)

Hi,

Whilst on a trip in Norway in early June, I noticed a spot appearing on some long exposure images that I took at "night" in Bergen. I edited it out in the images I posted but recently took some more long exposures in both daylight and at night (with a ND filter that I had cleaned thoroughly) and the spot is appearing again in the top right hand corner of the images. I'm pretty sure it isn't from the filter, but I didn't try any in low light without the ND filter. It seems to only appear above 4 second exposures, but on some even longer exposures (in lower light conditions it is sometimes less visible to the naked eye).

I'll try to attach some examples here of unedited raw images that I've just exported to JP format to reduce their size. Each one has been labelled with the number of seconds it was exposed for.

I'll follow up this post with a few more examples.

Thanks for any help or advice that anyone can offer.

Mal

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[malbooth]

I've uploaded an album with more examples and will try to link to it here.

[otto.f]

What aperture did you use to reach that long exposures? It seems typically a dust spot on the sensor which becomes much more visible above f8 than below. And can you get it sharper with for instance f22?

I have no Q and don’t know about its technics but in an M these spots come from the shutter in the first, say 1000 actuations

Edited August 15, 2018 by otto.f

[lucerne]

Very likely to be dust on the sensor. You cant clean it because the lens isnt removable, but your Leica main dealer can do it without sending it to Germany. Search the forum for entries “q dust”

[HighlandK]

I agree it does look like a dust spot which typically appear at the top of the image, being towards the bottom of the sensor. Try photographing a blank white wall or plain blue sky and use f22. That should show it up more.

[earleygallery]

Dust. Yes it can get inside fixed lens bodies!

 

If the Q is under warranty send it in to be cleaned. If it's out of warranty it might be 'easier' to PP it out.

[otto.f]

Advertisement (gone after registration)

In C1 you can eliminate the dustspots in one click for the whole range of shots you’ve taken, perhaps in LR too

Edited August 15, 2018 by otto.f

[malbooth]

Thanks for the replies. I shot these at a range of apertures - mostly f/4 to f/16. The Leica Q only goes to f/16 so I can't shot on f/22. In some of the low-light (almost dusk shots) at f/8 and 20 secs it is pretty invisible for some reason.

 

I don't know what is meant by "PP" (earleygallery) and "C1" (otto.f) above?

 

I will check the warranty period and take it back to my Leica dealer in Sydney.

 

Cheers.

[Leica Guy]

C1 stands for the post processing program: Capture 1.

 

F/16 is fine. Take a pic of a clear blue sky and I expect the dust on the sensor will be very obvious.

 

Yes, return to Leica under warranty. They'll remedy it.

[otto.f]

PP is postprocessing

[malbooth]

Thanks for those replies. I'm still using Aperture for editing or post processing as you say. Must move to Adobe eventually as Aperture isn't being updated by Apple anymore.