A6700: Intervalometer + Bulb Mode (Specific Shutter Speed)

[fx175]

I'm trying to set up my A6700 to record a Milky Way time lapse.
The optimum Shutter Speed for pinpoint stars for my setup is 14 seconds.

But I can't seem to set the Interval Shooting Func to use the Bulb mode (14secs) with Mechanical/Electronic Shutter in my A6700 Manual mode

Previously on my A6000 - I used a external intervalometer and it could easily select "custom" shutter speed intervals while the camera was in Bulb mode

Any fellow A6700 / A7R V / A7 IV owners mind sharing if it's possible to set Interval Shooting Function using a "custom" Shutter Speed ?

It seems like the built-in interval shooting function doesn't allow for any custom shutter speed or even exposures longer than 30 seconds.

 

[Dave981]

With the intervalometer you are restricted to standard shutter speeds. But with 0.3 EV exposure steps, you can get 13s and 15s options. An advantage of using the built-in intervalometer over externally triggered bulb mode is that you can use the electronic shutter.

If you're doing a single-shot time lapse, the intervalometer should do the trick. What you can't do with the built-in intervalometer is collect a stack, wait, collect a stack, wait, etc. For that you need an external controller.

I've done a few astro stacks (Bortle 7 so nothing exciting) so I'd be interested to know whether you seen any functional difference between the a6000 12-bit lossy compressed raws and the a6700 14-bit lossless compressed raws. I don' t know how Sony's compression schemes deal with very low s/n images. I've been meaning to test this but weather and sleepiness have indicated otherwise.

Likewise (I've been meaning to test as well this but haven't), other than number of files, is there a difference between 10 shots @ 20s and 40 shots @ 5s? In the past, I've usually lost a few shots of a stack due to vibrations, and with more shorter shots this would actually be less of a problem.