Random iceland notes from Andrew Marr: https://www.youtube.com/watch?v=m3SlpbI2TrY LOTS of links to sources. Really good International photography map of iceland. Highlights interesting tourist locations and good photographic sites. Buy online https://international-photographer.com/en/product/iceland-poster/ used 17-35 mm lens, 24 mm lens and tele. wide angle smooshes the mountains in the distance - not good. Took Polarizer. more gear (16:00) Pouches (think tank) look waterproof charger - power brick. 26,000 mA. (Anker) COULD I RECHARGE MY CAMERA WITH THIS? To recharge the Nikon batteries - recharging stations - What are they?? sandisk SSD - he backed up to two disks. 2 Tb. Samsung T3 - Gnarbox can backup without computer. ($254) - has internal memory of up to 246gB Osprey 5.40 -forty liter bag Lipo guard for battery storage 2) 10 things to know before visiting Iceland https://www.youtube.com/watch?v=PbW-VTrsikQ notes to self: 1) set up sp...
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Time lapse notes 1) https://www.youtube.com/watch?v=XZnaBHa2f18 They say if you do interval, you can download to any video editing software to combine. shoot manual. quality picture control (?) = flat minimum of 10 seconds of video. manual focus. try a test single exposure Interval timer mode: lock exposure, WB, Focus, No auto mode. You have to do a rough calculation of time 24 frames/second - 2 second video needs 48 images. Shoot a few extra frames. (might get tricky hen doing 6 second images.) 2) how to make a timelapse in lightroom https://www.youtube.com/watch?v=RpnFqQNgJnE Don't need third party apps Use slideshow module. took 1000 images in iceland import all photos into lightroom. put in their own collection. may need to change into a 16x9 format select all photos Cmd-A. Hit light switch next to sync button -turns on auto sync. Each change to a photo propagates to all photos crop to 16x9 click done, it propagates Can do lens correction and pro...
notes on youtubes: 1) Lenses I wish I had never bought. https://www.youtube.com/watch?v=Pgtat9ujhwY 24mm f1.4 sigma - the distortion too great for portraits. Image quality good, though. Misses focus at times. Sounds like it might be good for me. I may want this instead of the Rokinon. Samyang 24mm f3.5 - cheaper than above. "tilt shift" lens?? this is a shift lens. The manual focus is an issue 2) Reduce high-ISO grain. https://www.youtube.com/watch?v=GmV4heJ75Zg&frags=pl%2Cwn shutter 20 seconds f/2.8 can't see anything until get too ISO 800 Loads RAW images into Photoshop. increasing exposure in PS results in SAME image as if you used the increased ISO. Lesson - you get nothing more by increasing ISO IF you have an ISO invariant sensor. Which is mine? He discusses more on peterzelinka.com. Complete video on night photography there. Also backpack review fixing in photoshop. Use RAW. The ONLY way to reduce grain is to capture more light. Can incre...
Let's refocus My first goal is to guarantee I can get good images of the aurora. I am getting distracted by how to get good images of star fields with the Nikon. SO - Focus! What I want is either/and 1) good still photos 2) good time lapse 3) good movies. None of these require stacking. (except maybe good still photos) However, I would prefer my stills not be so long as to destroy the linear detail in the auraorae. So - I need to concentrate and practice getting good still night photos. Then work on time lapse and movies. points along this path: 1) determine good exposure values for various times. Check these for image quality. I will have to vary the ISO, and there will be a point at which they become too noisy. 2) learn to do the focusing in the dark without fail. 3)test the various exposure values, put out comparison images for criticism. after this Move on to time lapse. Learn how to change into a movie that doesn't go so fast And then to movies. No...
Test acquisitions 8/24/18
test: change the f ratio to see how this helps the focus parameters: 24 mm, 13 sec f3.5 ISO 1000 24 mm 20 sec f 5 ISO 1000 Comments: leaves slightly sharper. Much more trailing - 20 sec too long. Also - prior to the image acquisition, I changed the WB to Daylight. Much better star colors. When I try to stack, the star colors go away - READ ABOUT DE-BAYERING.
processing notes. Got the images from 8/13/18 at 1:00 AM working in Nebulosity. 1) pre process, with dark and flat frames. 2) align - using translate and rotate. At first I saved all the images, this is wasteful, but allowed me to see what was going on. 3) stack - using average. 3a) manual identification of the star takes a good deal of time 3b) automatic appeared to work essentially as well. 3c) to get maximum resolution in an area (In this case andromeda), pick two stars near to each other in this area. In this case, auto also worked well. There was smearing of some of the stars outside the area of interest - so what. I am surprised at how well I was able to pull out some detail. With the 24mm focal length, I was able to barely see M32, and some Mag 9.2 stars. can them move them to Lightroom to crop, etc. Issues: Color rendition is a problem. When you pre-process, the images come out as .fit files. I cannot see that they have color info. I might move a single image i...
useful links http://www.astropix.com/html/i_astrop/tripod/toc_tri.html " For fixed tripod pics try Sequator. It does actually correct for lens distortions." From Cloudy nights. https://www.cloudynights.com/topic/621840-why-are-my-astrophotos-so-grainy/page-2?hl=%2Buntracked#entry8646446 https://sites.google.com/site/sequatorglobal/ backyard astro, including sky window http://www.backyard-astro.com
some success last night regarding the focus issue. There were relatively clear skies, and I took the camera out. I got some test shots, showing the focus at 24 mm was acceptable, when done right. Moreover, I discovered a technique. Using live view, I can expand the image to include one star and actually do a decent job of focusing on that when it is magnified. So I won't have to rely on shining a light on my focus ring, or having to have a table of proper focus points for each setting of the focal length. However, the stars are oval.. Coma? It appears I did this at 85 mm. May want to try at 24. May be different. here is an image of Mars taken at 85 mm. Nice disk, overexposed by a lot. Would be interesting to see what I could do with the 300 mm. Exposure here was ISO 2500, 85 mm, f/4.5, 1.o0 sec Now, on to learning how to get a set of images to stack. What ISO to use, what exposure to use? And, time lapse movies. That would be good. I think I will ask c...
lens tests. yesterday, I tested focus on terrestrial subjects for the 324/85 and the 70/100 No surprise, at 24, the wide angle was not in focus at the infinity marking. Nope, it was between the infinity marker and 4 on the focus ring. Tests at 85 mm showed a different focus point, as did the 70/300. So for reference, here are the results: (for a focus at infinity) 24 mm : Between infinity and 4 85 mm : Middle of infinity mark 70 mm / 300 mm: Markings are difficult to align there is no real mark to show you where you are. autofocus and visual focus are accurate. Manual focusing using live view was accurate the autofocus was accurate Test on star - Stepped outside this AM, and tried star images. STILL muddy. 24 mm focus at inf-4 Note leaves appear to be sharp. I think I need to do a series just of stars. Do it with both the 24/85 and 70/300. Stop down the lens on some other tests. Other items: I have found a paper that said that 100 ISO was the proper se...
This blog is not for others to learn from (yet). Primarily as a diary of thoughts, ideas, successes, and failures as I learn to do this. Essentially notes to myself. I have looked for advice online, and my needs are so specific that general advice is not helpful. I will have to do it myself. Probably so much the better. The inspiration to start astrophotography was a trip we will be taking to Iceland this October. I want to capture the northern lights as best I can. One goal would be to make a short movie of the lights. Of course, much depends on their undependable weather. So - the Sony I currently have is inadequate to the task- time exposures are not possible, sensor is too small to be very sensitive, etc. The Sony is an excellent, excellent camera in many regards, which I may elaborate on in the future, but not for astro photos. I purchased a Nikon D750 after much thought. I had 25/80 and 75-300 lenses already from a film camera, and this seemed like the best full frame ch...