Page 1 of 1

HDI Work w/ Both Histograms

Posted: Wed Nov 23, 2022 3:24 pm
by kaymann
I am finding my EAA with SC is something that worked great the first time I used SC. However, now I just cannot do anything right. When I try stretch the histogram it is so sensitive it turns into a horrible mess. Why do my saved images look horrible - a clue to the problem: auto stretch turns it into a very bright mess and Auto Color turns it into a green overly bright mess as well. Most times even with the histogram set to log it is tight and very unmanageable.

So the question is how do start over like when I had first SC light and everything worked. IOW how to get back to Default Settings?
I am confused do I stretch the little histogram to the right or the big one underneath...
If I don't play with the little one how do I make sure it is set correctly so it does not screw up the main Histogram.

SC the latest of Weekly versions.
Darks done through SC at the same Brightness, Gain, Temp, Flats done through SC with Bias at 50% Tru ADU 20,000 to 32,000.
Camera Analysis complete and the analysis mostly agrees with the factory specs.

C9.25, Meade FR-FF f/6.3 at 85 mm Meade factory Verified BF, ASI533MC Pro 0°C, DeBayer RGGB (verified for this camera), Gain 101, Brightness 50, WB-R 50%, WB-B 50%.

PS You maybe sensing I am thinking of quitting and going back to ASI Studio but I hate the lack of options by ASI Studio. I am getting to the point of utter frustration and walking away so I am taking it a step at a time. SC is my last frustration (OAG is now under control and working great). I have DSLR and EOS Backyard forever and a day.

Re: HDI Work w/ Both Histograms

Posted: Thu Nov 24, 2022 2:24 pm
by admin
Hi,

from your description, one possibility is that the individual frames are very dark for some reason, meaning that the stretching has a lot of work to do bringing almost no signal up to visible. One thing that can cause this is if you have previously applied a display stretch (using the mini histogram on the right). This gets remembered along with other camera settings, and if you don't spot that it is still active, you can think you have well exposed individual frames when in fact they are really dark.

The simple way to reset all camera settings is to start the camera with the CTRL key held down - that will put everything back to default. It's also worth going back to basics with no darks/flats or other processing to begin with (just live stacking). If you can get that configuration working then you can start adding back things like darks and flats one thing at a time (just in case one of them turns out to be the issue).

If you want to take a more drastic approach to resetting everything to default, go to the settings and press the 'Reset Settings' button (bottom left). You will then have the choice of which bits of the SharpCap configuration to wipe clean.

Hope this helps,

Robin

Re: HDI Work w/ Both Histograms

Posted: Thu Nov 24, 2022 5:20 pm
by kaymann
Perfect response thank you Robin!

One question I do Solar (*.SER) during the day and at night I will pull off the solar filter and go right into EAA (*.FITS)with the exact same setup including cameras.

Is there anything I have to do to make sure it is not remembering the settings for solar?

Randall

PS You did it Robin thank you I discovered brightness setting (offset) was set too high and causing all my problems. Last night I kept it at Zero (0) and all went well any reason to set it at something else?

Re: HDI Work w/ Both Histograms

Posted: Fri Nov 25, 2022 2:26 pm
by admin
Hi Randall,

you may want to look at saving default settings for each type of imaging in 'Capture Profiles' - see https://docs.sharpcap.co.uk/4.0/#Capture%20Profiles - that will let you quickly choose your Solar and Deep Sky settings.

You can also turn of the auto restore of settings - see https://docs.sharpcap.co.uk/4.0/#General%20Tab

cheers,

Robin

Re: HDI Work w/ Both Histograms

Posted: Sat Nov 26, 2022 7:12 pm
by kaymann
Robin, I am sorry you had to remind of your profiles feature. I have really simplified my observing with Profiles not only for Solar but Solar White Light and Hydrogen-Alpha, Neb's etc. wow what a nice way to remember settings for different scenarios. Thank you for your assistance.

I am still a little confused on what effect the "little" histogram has on the any saved FITS or SER's and second how does it affect the "big" histogram. In other words cand the little one screwup a SER vid or mess with what you are trying to do with the big one?

BTW I am still searching for information on recommended Brightness (Offset) settings for different scenarios. Astrophotography is like herding cats: Get the offset right and the exposure jumps out, adjust the green on the histogram and brightness jumps out etc. etc.

Re: HDI Work w/ Both Histograms

Posted: Sun Nov 27, 2022 3:23 pm
by admin
Hi,

adjustments made in the mini histogram on the right only affect the image as displayed on screen, not any save files (exception - if you use the save button in the mini histogram then you do get the adjustments included). Adjustments made in the live stacking histogram will affect the files saved from live stacking with 'Save with adjustments' and 'save exactly as seen'.

If you are thinking about the big (non live stack) histogram then the changes made in the mini histogram *do not* affect what is shown in the big histogram.

Finally, offset/brightness setting... For high speed (lunar/solar/etc), it will make relateively little difference - keep it set fairly low. For deep sky, it can best be set while taking dark frames - adjust the brightness to ensure that the dark frame histogram peak is separated from the left hand side of the graph. In all cases, use the same value for all related types of frames for a single target (dark/flat/light/etc).

cheers,

Robin

Re: HDI Work w/ Both Histograms

Posted: Tue Nov 29, 2022 5:54 pm
by kaymann
Robin, thank you for your response so here is, I believe the crux of my problem... Because I want to record my EAA session in Fits for later processing I want to do all my histogram adjustments in the big one so what I see is also what I get- correct? If that is true, how do I set the small (display) histogram to neutral or off completely?

PS, Robin your help to date has been instrumental in bring EAA back to life for me...

Re: HDI Work w/ Both Histograms

Posted: Wed Nov 30, 2022 1:57 pm
by admin
Hi,

if you are recording the individual frames in FITS using the 'Raw Frames' saving option in live stacking then those frames are unaffected by either the adjustments you make in the mini histogram on the right or the adjustments made in the live stacking histogram, so no worries on that front. In either case, you can reset the histogram stretch to default using the 'anticlockwise arrow' button (intended to be a reset/wind back/undo symbol). In the case of the mini histogram, this sets it back to no stretch. For the live stacking histogram it sets it to a weak stretch that brightens the shadows a bit.

Glad to hear that you are enjoying EAA using SharpCap :)

cheers,

Robin