K-5 video hotspots work around (fixed)

Hi,

I noticed a couple of moderately large sensor spots (green and red on my 1080p video in low light, these are not high iso noise, these are like dead pixals with a slight halo around them, the green is brighter, i have 2 bright ones and one faint one, on the left hand side in this pic.




i tried to sensor clean them with a couple of passes, but to no avail!! it's not the blob issue, as they are completely different, and at first i thought it was dust or something particular, but they seem stuck fast and consistantly in the same place yet my sensor is a week old and mint

nothing shows up on the sensor info

i have since found a workaround, not just for zooms but for primes.

as the problem seems to be an overlaying sensor info image, on top of the video, and so by selecting a photo mode like auto first, and then selecting live view, then selecting video removes the problem for zooms, but for primes you cant, as live view is not available, however, if you put a zoom on, select auto, select live view, then without switching the camera off change the lens to the manual prime, the problem is corrected yet again, so no more spots, i appreciate that the live view goes off while changing the lens, but it seems to work this way. it's not the sensor, it seems it's a sensor image /info overlay, why this happens is a mystery.

hope this helps some video junkies on here

apart from that i have managed some really good video on this camera, and i'm very pleased

the low light video is about 300 times better than the k7

I would be careful of changing lenses with camera powered on. There have been one or two stories of lenses packing up - ie those with the the electrical contacts.

Having said that, I am not sure why the spots disappear with the workaround you suggest!! The spots do look rather like 'hot-pixels' to my eye. I have some on the K7 that show up on stills with the NR switched off. They often 'disappear' when using a programme like LightRoom at default settings.

i can't speak for video as haven't looked that closely.

interesting to see that the K5 is SO much better in low light video!

Andy

Are you suggesting that dust shows up as a lit pixel rather than a mote on the image?

thankyou for your comments

i only tested the idea once so i'm glad i read this before i tried agin. but it does work, the spots go once this process is done, i admit it feels wrong taking the lens off while the camera is on, and i didn't know about the charged sensor when powered.

live view does not come up with the richonen 50mm f2 for some reason, maybe a setting somewhere.

i only get this issue on video in low light, my raws are fine, and jpegs the same and all clear, but they are always there whilst recording video i suppose, but are not so noticable in good light, if at all.

i'm glad you told me about the sensor and issues with switching lenses, i wont be doing that again, but i was pleased that they went away with this method though how ever bizarre.

maybe its linked to live view in some way. anyways the rest of the camera i can't fault, and i'm really having fun with it, i love my pentax, regardless of hot spots.

do they ever go away i tried pixal mapping but that didn't work

Tarryn

indeed sledger, that's what i initially thought, i'm not sure, that's what it seems like to me, however it does look like a hot spot or two, now i have seen some related web searches

As far as I am aware, dust cannot sit directly on the sensor due to the filter. Any dust in front of the sensor will only block light and therefore will result in a dark spot.
Only leakage currents can cause 'sparkles' (or hot pixels).
I'm no expert, so I may be proven wrong about this.

Pixel mapping is available on the cameras and the "hot pixels" can be mapped out of existence.

Dust is dark specks and these lie on the low pass filter that covers the sensor.