Issues with Settings - Jupiter

[eric.parsons]

Good afternoon all!

If this is the wrong forum, I humbly apologize and ask that this be moved to the right place. I've been using Sharpcap with an SvBony SV305 for over two years and have not had many (any?) problems, save for when my Dob's mirrors got out of whack and we had to fix that. However, my son and I have run into what I think is an odd issue that cropped up most recently when trying to image Jupiter.

The live feed and resulting SER files are very, very pixelated. It doesn't really show a disk, just a spiderish looking thing with some hints of dark bands. However, this only happens on HIS laptop (which we only use if I'm doing long exposure deep sky photography with mine at the same time). His is an ASUS gaming laptop, a fairly power rig (I don't have it near me right now, but suffice to say, it's a good machine). When using mine, apart from the images having a slight yellowish cast, this does not repeat. My laptop is an HP-15dw0037wm--standard everything, no upgrades (though that's coming in two months). I suspect that it's the graphics card in my son's laptop...that is, it's pretty overpowered, so to speak.

My mirrors are fine, this is not a problem there or with focus...or at least, I'm as close to 100% on this as one can be. I suspect it's either a settings issue or a compatibility issue between the laptop and the camera itself (or perhaps the camera is going bad?). At any rate, I've re-reviewed the excellent guide on capturing Jupiter and I'm at a loss. I've had excellent success before, so I figured crowdsourcing some ideas to try was a good route.

My most pressing questions are: what settings in the camera controls could do this (should I not touch Gain? Sharpness? Contrast? etc.)? Is there any chance of a cable mishap? Should there be something that I do differently in the settings when the GPU is better/worse?

I realize I've thrown out a word salad, but I was so disappointed that my first attempt at Jupiter in some time was quite a dud and I can't figure out why. I can upload the resulting file in a bit, my main PC is unavailable at the moment (flight sim is running on autopilot for FSEconomy), but any thoughts...no matter how ridiculous they may seem...would be appreciated.

[eric.parsons]

A couple of updates. I had a very short amount of time to get out to get Saturn tonight (which is my preferred first to settle any focus issues). Images were fine (if a little green/yellow on screen). A little soft-focused, but we were trying to hurry to save some time. No spiky/pixelated photos/ser, though the histogram just looked...odd.

I'm thinking a couple of things. Perhaps I pressed the "autostretch" button on the histogram. But I'm really leaning toward this being a pc specific issue.

I've noticed this will not let me upload an SER file, but alas...they look horrible.

[admin]

Hi,

we do have a limit on file size for uploaded files here on the forum (it helps to avoid having to keep enormous amounts of data backed up). You can of course do something like upload the larger files to Google Driver, DropBox, etc and then post a sharing link so that others can download them.

Having a look at the problem file (or even a screenshot of what it looks like when displayed) may well help understand what is going on.

Some things I can think of that might be causing this

* As you suggested having the display stretch enabled then adjusting settings to make the stretched image look good can mean that the saved image is really faint

* The viewing software on the problem PC may not be debayering the saved images, which could leave them looking pixellated and monochrome

I do suspect that it is some difference in settings (either in SharpCap or in the SER viewing software) rather than being a result of hardware differences - of course there are *lots* of settings that could be different... One good trick is to open the camera with the <CTRL> key pressed down - that should stop SharpCap from re-loading any previously used settings for the camera and put everything back to the defaults.

cheers,

Robin

[eric.parsons]

Robin, thank you for your reply. I thought I still had the files--they may be on my son's laptop--but I didn't have them readily available.

That said, for my laptop, I did what you recommended and reset to defaults. I also re-read the manual. Somehow I missed that there is a focus assistant. To be honest, I mostly use SharpCap these days for the polar align for DSO photograpy and hadn't used it for planetary with my Dob for some time. I had to fix my mirrors (that's along story in itself).

Nevertheless, we just got back in from an imaging session on Saturn and it was much improved. It's supposed to be clear this Friday night, so while my scope is running data on Andromeda, Kris and I will use his laptop on Jupiter.

Again, thank you for your suggestions! My next major scope purchase is likely to be a Nexstar 8SE...I'm hoping that having the planet tracked helps with other issues. I've had good results with the Dob, but find I like to have it available for visual. It's a great way to meet the neighbors.

[admin]

Hi Eric,

good to hear that you have got things working better now

I hope the weather holds good and you have success on the planetary imaging.

I must admit that I have a Nexstar8SE and the telescope hasn't come out of a storage box for at least 5 years... The problem I found with the SCT is that it is *so* hard to get rid of tube currents - it doesn't really matter how long you wait, the top of the telescope is cooled by the sky and the bottom is warmed by the ground so it will not reach equilibrium easily. I guess lots of people do very well with them, but I have never really got on with it.

I recently picked up an 6" classical cassegrain for a decent price and it serves much the same purpose (1.8m focal length). Good on small deep sky stuff like planetary nebulae, but haven't actually tried planetary on it yet.

cheers,

Robin

[eric.parsons]

That's too bad...I've long wanted the NexStar--to make seeking, finding, and imaging a bit easier. My scopes tend to stay in my garage, so they are (mostly) already at temps...I say mostly because when it's really hot, the garage holds the heat more. I get what you're saying, though.

I am happy to say that Saturn turned out very well--though there's a weird purplish accent to it that's from the street lamp.

and to be clear, I never thought this was a problem with Sharpcap itself. I love this software. Love it. I think I messed up somewhere and was confused on the fix. I do think going forward I'm going to have to be cautious to have a profile for planetary and one for the polar align.

[admin]

Hi Eric,

nice satturn - glad that it all came out so well in the end.

I get where you are coming from with the GOTO Nexstar mount - it is fairly quick and easy to set up, although the GOTOs are not the most accurate (quite a bit of backlash). For a portable setup it's probably quicker to get going with each evening than an EQ mount.

cheers,

Robin