FRAME RATE and SHUTTER SETTING

[YOURJONES]

Hi

 

QUESTION 1

I tried the planetary video with my Nikon D5600. I got a frame rate of about 94 FPS. Does this mean the 60 FPS from the camera's own setting options is only theoretical, and that the actual rate can be high as 94 when the frame resolution is reduced to LV size?

 

QUESTION 2

The same system as above. I can adjust the ISO when filming in the planetary mode, but seems that the "shutter" setting does not work the way you want it to. The BYN wants to achieve high framrate regardless of your shutter setting. Is this the case?

 

Thanks

[astroman133]

BYN does not use the camera's movie mode, so the camera's movie frame rate is not applicable to BYN.

BYN's frame rate is the rate at which it downloads LiveView images. This has to do with the speed of the USB connection and your PC. The ISO and Shutter settings do not affect the frame rate only the brightness of the frames. This is how the camera is designed to work and BYN cannot change that.

[admin]

IT is not BYN that controls the frame rate, it is the camera.

The way LV works is that the camera makes a LV frame available one after the other, as fast as it can.  BYN listen to the image ready event and download it as soon as one is available.

Some camera will provide more frames that other in the span of 1 second, yours seems to give a lot at 90+.  Most are < 20 to 30 FPS.

Adjusting the shutter will not alter the frame rate.  In LV those settings are applied as a digital/brightness adjustment to the image.

[YOURJONES]

Thank you! Now I understand.

 

I noticed from a test video that I have just taken with D5600 connected to PC using a USB cable that there are many repeated consecutive frames. On average, there is a new frame every 2.5 frames. I could basically math the actual, effective frame rate to be around 36 fps. I am sure this is due to the USB cable. Is this frame rate too low to image planets?

[astroman133]

If you are saying that BYN is downloading the same frame multiple times, then this should not be happening.

With my Canon T5i I get about 15 LiveView images per second. This is plenty fast enough for "lucky" planetary imaging.

[s3igell]

1 hour ago, YOURJONES said:

...around 36 fps... Is this frame rate too low to image planets?

This is a very respectable Frame Rate for a Dedicated Planetary Astro Camera.  It is a GREAT Frame Rate for a Tethered DSLR (and is likely limited by the Camera's USB2 Port ).

It is definitely more than enough for Planetary Imaging.  Even for the Speedily-Rotating Jupiter, it is usual to be able to Stack 5 minute Videos without needing to worry about Derotation - and 5 min would give you 10K Frames to Stack.  Seeing Conditions and Equipment / Resolution will likely be bigger Factors...

[admin]

5 hours ago, astroman133 said:

If you are saying that BYN is downloading the same frame multiple times, then this should not be happening.

With my Canon T5i I get about 15 LiveView images per second. This is plenty fast enough for "lucky" planetary imaging.

IF BYN downloads the safe frame multiple times (very unlikely) this is caused by the camera raising an event for the same frame more than once and if this is the case BYN has no way of knowing this is the case.  I have never seen this happening with any models so far.