Jeff, your first attempts are a lot better than my first attempts were last summer. Actually, after you understand the NightCap Camera app, it becomes much easier and faster. A couple of things that I didn't initially do:
1. In settings (the gear button), turn on the exposure delay in the middle of the screen... I set my delay for 3 seconds which is plenty of time for any induced vibrations to settle when pressing the "shutter release" button. Alternatively, you can use an external (optional) blue tooth shutter release, available on E-bay for about $7, or earphone controls if your iPhone X has a mini jack. I prefer just using the 3 second delay as there is less to fiddle with in the dark.
2. In settings, after you turn on the Interval Programmer and set the number of seconds for stacking (in the EXP box), slide on down and hit the ISO Boost button, try low for brighter objects and high for really dim ones like face-on galaxies. This can help a lot and most of the noise can be cancelled out during the stacking process. Since you will set the ISO manually, the Boost only goes into play when you need to go to really high settings. The iPhone limits ISO; NightCap lets you take it higher. Don't worry about graininess; if you stack for 10-20 seconds, most of the noise and grain will disappear.
3. In settings, about 1/4 down from the top, is the light button and the noise button. I have found that the light button does help brighten an image by sliding the dot to the right on the sliding bar; most of the time I leave it 1/3 to 1/2 of the way across the bar. The noise setting can be used too, but I have not tested it to see if it actually does much.
After making these setting, you have to hit the gear button at the top to get back to the imaging screen. BUT, before taking photos, you have to activate the settings you made, so hit the star button at the bottom of the image screen. This opens a small menu which allows you to touch the Long Exposure button to activate it. If you want, you can also activate the extra light (sun button) at the bottom of the menu or the noise cancellation (square, gray box)... then touch the star button to close that menu.
At the perimeter of the image screen are the manual controls which you have obviously found. Touching the screen, briefly reveals those manual toolsI; I usually start with the exposure on the right side of the screen, moving the sliding bar to about 1/10 second. I do this because if I put it on 1/3 or 1/2 second, it is much more difficult to get perfect focus... because a 1/3 exposure speed slows down the reaction of the screen when focusing, updating every 1/3 second. I then work my way clockwise around screen, setting focus at the bottom, ISO on the left, and white balance at the top, then I return to exposure and set it to 1/4 to 1/2 second. If changing the exposure brightens the image too much, I go back to ISO and slow it down to darken the image.
You will see at the bottom of the image screen FOC, EXP and WB with red dots next to the letters. As you move the sliding bar to adjust Focus, Exposure and White Balance, the red dots next to the letters will change to green, which means that you have adjusted them and they are now locked for the exposure... but you can touch to re-adjust them.
Focusing must be performed first by using the scope's focuser which I do before I even attach the phone, and I lock the focuser, tightening the drawtube set screw. The phone's focus can be done automatically by touching the screen where some stars appear (touching the screen puts a small focus box over the point on the image you touched), give it a couple of seconds to find best focus. But I always use the FOC sliding bar for manually setting focus because my eyes seem to find the best focus easily... and it seems never to be at 100 which is infinity according to NightCap. I have found best focus on my iPhone 6+ usually close to 84, but sometimes as low as 76. And, by setting the focus manually on the sliding bar, it locks it when I let go (the FOC light changes from red to green).
White balance controls the image tint. With your white phosphor tube NVD, if you drop white balance to 2600 Kelvin, your astro image will probably turn a nice color blue. At about 4600 K the image will be pretty neutral and above 5000 K, the image will be increasingly green, all the way to a black-green at about 8300 K.
The best thing about NightCap is that you see exactly how light or dark your image is going to be when you change the ISO or EXP sliding bars. If you want the image darker, slide the ISO down and you will see the changes occur on screen. If it is too dark and you are on 1/10 second exposure, change EXP to 1/8 or 1/4 second. Keeping the ISO as low as possible will always help control noise in the image.
What I don't like about NightCap is that it does not hold FOC, EXP, WB and ISO settings between images. And if you close the app, it will usually delete ALL of the settings you have made, including in the "gear" menu. But not always. I think there is a time delay on the deletion process but not sure.
NightCap was not intuitive for me and I had to read the tutorials several times to understand its mechanisms. But now, it is very fast for me to take images. I can slew the AZ Pro to a target and take a photo in less than a minute if the phone is already attached to the NVD. I usually take whatever photos I intend at the beginning of my observing and at the end.
Experiment with NightCap; it is a surprisingly robust application that extends the phone's capabilities. Take several images using different settings of one target until you get exactly what you want. It gets easier! I now use NightCap as often as the iPhone camera app. I was in a 15th century church last week and wanted images of the stained glass... I was probably the only phonetographer who actually got satisfactory images of the windows, because I was not relying on the algorithms my phone uses for automatic exposures. With your 16" Dob, your Mod 3 and your new iPhone X, you are going to produce some amazing images! Look what you already have done... M51 is an amazing image, and your globs are great! Have fun.
Ray
Edited by GeezerGazer, 18 June 2018 - 03:09 AM.
