The app I've been using does have a bulb mode. The app is called Nightcap pro. That said, if one is buying a phone for this use it might be a good idea to investigate Android phones since they do not have the 1/3-1 second limit on exposures.
OK, so this time I couldn't broadcast due to Camtwist crashing & Chrome not seeing it. Otherwise I had a great first light with the new 'Spider House' AT12IN on the CGEM. The first two pictures are M42, Orion, first with a 2" eyepiece, then zoomed in with the 8-24mm zoom. The second two pictures are comet lovejoy using the same eyepiecs. These were taken with a Nightcap Pro beta version. 1/2 sec base exposure, ISO 2000, in the 'bulb' mode of the app. I don't remember how long each capture was exactly, but they were all at least 10's of seconds.
I was asked to show the Comet in my broadcast last night but it was too late by then. I had totally forgotten it was up there and had all night to see it, but when I was asked to show it, it was down behind my shed Good to see that you captured it.
M42 shows up good too. Well done
__________________________________________ Ken James - Snake Valley Australia CAMERAS: Samsung SCB-4000, Mallincam Xtreme & Xterminator, 3 different Revolution Imagers, 2 ToUcams, SX-5c, Canon 350d, 2 different IMX224's (an RI & RT) and an RT178. Broadcaster on NSN as 'Snake Valley Australia' HERE --> www.nightskiesnetwork.com/ - Video Astronomy Website: ballaratman.wix.com/videoastronomy
I figured out that I should be locking focus at infinity, also, the secondary shadow is there because I need to use an eyepiece closer to the aperture of the phone camera, and make sure it's getting fully illuminated.
From further research on a-focal astronomy, I learned that the ideal eyepiece focal length to use is one that has an exit pupil equivalent to the cameras aperture, where the exit pupil is the eyepiece focal length divided by the telescopes focal ratio. In the case of the f/4 scopes (AT8IN & AT12IN) I use, and the iPhone aperture of 4mm then a 16mm focal length eyepiece should be used. Luckily 16mm falls right right in the middle of the range of my 8-24mm zoom eyepiece, which is probably why it's working so well with it. In addition, I will need to pay attention to the eye relief to make sure my distance is at a good place.