Re: Nikon D5000 Subframe.
Lacy Rhoades <[email protected]>
| Newsgroups | gmane.comp.multimedia.gphoto.user |
|---|---|
| Message-ID | <[email protected]> |
Hi Steve So, a few things. Can you do the HFD at a lower overall resolution and/or a higher JPEG compression setting? If so, what about changing resolution setting inside the camera via the --set-config argument and then setting it back to normal when you need to? I assume you already know about list-config, set-config etc. if you’re changing the focus programmatically. I don’t think you can do essentially a sensor crop using anything specific to gphoto2. If there is some "sensor crop" setting in your camera, again, you might find luck using --list-config but the area you’re looking at must be in the center of the image. Can you speed up the network connection? Ethernet? 12MB isn’t really so big in 2019 terms. I admit I do not understand your HFD goal but what does the in-built autofocus not do well already? Does it focus on the skyline or trees when you want to focus on the sky? If so, can you change the focus points in the camera? Just to say that Nikon etc. have spent a lot of brain on how to focus, so it’s nice to leverage that when we can. > On Dec 9, 2019, at 9:53 AM, [email protected] wrote: > > Hi Guys, > > I use a Nikon D5000 over a network to take astro-images and I control the camera with gphoto2. I'm in the process of implementing an auto-focus routine using HFD (half-flux diameter), which is the radius of a circle containing half the flux of a star. In order to get best focus you need repeated exposures downloaded over the network, which is quite slow as each photo is about 12 MB. Is it possible to take a partial frame by specifying the position (on the sensor) and size of the subframe? So instead of the frame being 4,288 x 2,848, it could be 400 x 400 around a star? Much smaller and less network load. > > Thanks, > > Steve. > > > _______________________________________________ > Gphoto-user mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/gphoto-user _______________________________________________ Gphoto-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/gphoto-user