Originally posted by amkia
The problem is “sensor overheating” after about 10 min, which automatically shut down the cameras, so I am not sure how he got it on 20 min! also
with cameras nowadays with insane ISO setting of 12500 still he went for Bulb at higher than 10 min..?
Can you please show me proof that 60D sensor will "automatically shut down the camera".
Yes, the amplifiers on sensors can get warm during a long exposure, giving rise to an imaging artifact known as "amp-glow"(which I can't see any
evidence of here), but I have never heard of any camera that shuts down because of it. I am quite familliar with Canon's EOS line of cameras... I own
9 of them (although I dont have the 60D), and none of them do this as far as I'm aware.
Anyway, here's my analysis of the photograph (for what it's worth):
The length of the star-trails certainly lends credence to the 20 minute claim. From what I have seen, I have no reason to doubt the protographer when
he says it was a 20 minute exposure, but I think it would be helpfull if he could post the original jpg/raw with the EXIF data intact.
The trails are perfectly straight, so it's reasonable to assume that the camera was securely mounted on a tripod for the duration of the exposure,
although a double exposure/"photoshopping" can not be ruled out.
The unidentified lights in the image are not "trailing" like the stars, which suggest that whatever the unidentified lights are, they are stationary
with respect to the ground/camera.
The colour/tint of the unidentified lights is very close to that of sodium street lights.
The middle light in particular resembles a lens flare (as has been noted by previous posters on this thread) or "ghost" - they often have this
characteristic shape. I'm not saying it is a lens flare/ghosting, but I don't think the possibility can be ruled out just yet.
The lighting on the trees in the foreground suggests that there are some street lights just outside the camera's field of view. That's just the
right conditions for lens flare/ghosting.
All of the above points suggest that what we are seeing here is light that has come from a stationary source/sources on the ground (I don't think
it's likely that it's due to geo-stationary satellites, although this is a possibility).
There is also the possibility, if the photographer was shooting behind glass, of a reflection of something behind the photographer. Likewise, if the
camera's view finder was left uncovered during the exposure, light can enter the camera from behind and find the sensor.
To sum up, although the photographer says he saw a light/object in the sky, the photographs only show what could quite easily be accounted for by lens
flare or a reflection from lights on the ground. I don't see anything here that would suggest it's anything else.