BlurredImage

I am sorry, I posted my question wrong.
I am experimenting with long exposure and the night sky. I am taking multiple pictures using a tripod and a MC-DC2 remote cord. Most exposures are around 15 to 30 seconds. The problem is with changing lenses or lens settings 15 minutes goes by real quick. Then I need to reset the long exposure setting on the camera. I assume this 15 minutes in long exposure keeps the functions of the camera from over heating and causing problems with the circuitry? Maybe I just need to stick with one lens and one aperture setting at a time.

Triplets Loc: Reading, MA

I'm not sure I'm understanding your issue. I've done as many as 15 exposures of 5 minutes each with no over heating issue with my D750.

Regards,
Dennis

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juan_uy Loc: Uruguay

If I understand correctly (I'm not sure I do), you are talking about the long exposure noise reduction feature. That's not for preventing heating of the sensor.
What it does is takes a second shot, of the same length (shutter speed) with the shutter closed, and uses that shot to remove heating noise from the original capture.

When I do astro I disable this feature as it takes double the time to expose. If I want to have a dark frame, I take shots with the lens cap on, and use them to remove noise off camera.

Hope this helps/answers your question. If not, please further explain and I'll try to answer

jerryc41 Loc: Catskill Mts of NY

Something here might help.

https://digital-photography-school.com/how-create-dynamic-car-light-trail-photos/
http://www.clarkvision.com/articles/meteor.photography/
https://digital-photography-school.com/night-photography/
https://digital-photography-school.com/tips-for-getting-proper-exposure-for-night-photography/
https://www.bhphotovideo.com/explora/photography/tips-and-solutions/10-essential-tips-night-photography
https://www.lifewire.com/tips-for-nighttime-photography-492831

SuperflyTNT Loc: Manassas VA

I’m not sure what you mean by “ Then I need to reset the long exposure on the camera.”
If I’m doing exposures of 30 seconds or less I just shoot aperture priority. If I’m shooting longer than that I shoot manual and use either Bulb or Time for the shutter speed. What exactly is this “long exposure” setting you’re talking about?