Discussion in 'The Lounge' started by CraigSmith, Jul 14, 2020.
Sorry, this is apolitical. I think.
But maybe the sky is falling.
From my back yard.
It has been pretty spectacular the last week or so . Will be really cool later in the month in the west after sunset . Did not see anything in print but if you look at its time cycle of the orbit , the last people to see it where the Asyrians about the time they started their calendar . The Egyptians wouldn't lay the foundations for the pyramids for another 1500 -2000 years give or take . WR
Any special equipment to take the photo?
Looks like a good excuse for an IV fishing trip to check it out.
I have seen photos published that were taken with a 200 mm lens that looked really good It is pretty bright so no long exposures . Really shows up with binoculars , you can then see it naked eye once located . Has been in the northeast sky just above the horizon early morning , an hour before sunrise but I am not sure how much longer it will be visible in the AM . Staring about the 20th it will be visible after sunset in the northwest sky . Hope that helps . WR
I haven’t been able to see in AM from my home due to marine layer.
Last night first time I got a good evening view not obstructed by marine layer.
Though it is getting dimmer, it will be easier to see as it appears higher in the sky and later after sunset
Looks great in binoculars. I hand hold a pair of 7x50 and also tripod mount an 11-80 pair that is too heavy to handhold effectively.
My shots were with a 70-300 Zoom on a Nikon D7100. Most were at 135 and 200mm settings. ISO 400 with exposures from 1 to 6 seconds. All at f5.6 aperture (widest for the lens I was using. Having a 70-200 f2.8 lens would have been great but those are pricy.
The first image I posted was cropped from an image shot at 210mm. The second, taken earlier, at 135mm and not cropped.
Any camera with many manual aperture and shutter speed settings and manual focus option will work. Megapixel count doesn’t matter much. So this means most DSLR and Mirrorless. Auto focus systems won’t have enough light to work. I manual focus on something a long way away while it is sill light. Don’t rely on hard infinity focus stop since actual focus will be affected by temperature. Need a solid tripod. To avoid vibration from triggering the shutter I use a remote but self timer will work to.
I try to have something in foreground to provide some context in the photo. At least some trees. I wanted to go down and shoot with OB or Crystal Pier in background yesterday but marine layer precluded that.
Even if you have a DSLR or Mirrorless camera with the basic 18-55 or 15-45 kit lens you can get good shots. The comet will appear smaller but if you compose with foreground stuff you can get a good composition. If you look at a lot of shots posted online you will notice the comet is only a small part of the image.
There is a lot of other stuff that goes into getting a good digital image. Some is in those “complicated” settings buried in the camera menus and some in post processing with photoshop or similar tools.
I used to do a lot of wide field astrophotography with film cameras and no telescope. I have all sorts of tables for calculating exposures for celestial objects and how long an exposure I can get with out getting trails in the image if not using a tracking device. I ignored all that last night.
I did do a little bit of editing on my phone with Snapseed app to edit out plane trails, desaturate the reddish glow from city lights and mess with contrast to better show the tail. I can get a bit more out of these images with photoshop but won’t do that until I have a few days worth to go through.
Here is an example of another comet I shot more than 10 years ago. notice the comet is only a small part of the image. Not impressive but It was an attempt to compose something interesting.
I didn't photo but was out along the Carizzo escarpment on a hunting trip and about 45 min before shooting time it was beautiful . Nice composition , Cosmic and suburban tough combo there . looks good with gods thumbnail to the right . Cheers .
Just in case it wasn’t obvious from my comment about the marine layer, I am shooting from city, Serra Mesa, with all the light pollution to contend with in addition to marine layer.
If I had shot these images from a darker location they would have been much more impressive.
For those having trouble finding this thing there are several astronomy apps available for phones that work in conjunction with the build in GPS. I was getting shots that picked up comet before I got a visual on it with binoculars. I started with a wider angle setting on the Zoom lens to pick it up then adjusted the zoom and tripod head position as needed. A good solid mount that is easy to make small adjustments with very helpful
I might have to take the binoculars I use for plane spotting to work one night here pretty soon to get a peek at this thing. Figure if I can read the registration off of a plane 2mi away it should do the trick nicely lol
Key thing is light gathering ability and not magnification. An exit pupil of about 7 is desirable. To get exit pupil divide the big number (lens aperture) by the smaller number (magnifications) in the binoculars specs. So a 7-50 binoculars has an exit pupil just over 7. This matches well with the maximum that a human’s eye pupil can open when they are younger as we age the pupils don’t open as much. So a binoculars with smaller exit pupil may work just as well for older people like me. I can’t see dark sky stuff now as well as I could in my 20’s.
The other thing that is important is the size of the opening at the big end. Bigger opening gathers more light. And since this is a function of area even a seemingly small difference can make for a brighter image. My 11x80 binocs gather more than twice the light as the 7x50. The comet is noticeably brighter in those bigger optics. Need a tripod to mount on though since too heavy to handhold.
Higher magnification isn’t necessarily good. Higher magnification gives narrower field of view and smaller exit pupil. Magnification over 20 is going to be about the highest useful for what most of us can afford. Magnifications between 6 and 12 easier to manage. Now if you can afford pair of Fujinon 25x150 binoculars at $7K then go for it.
Also, even with a camera that doesn’t have manual focus it may be possible to get a good image if the camera has an infinity focus setting. Sometimes it may be called a landscape or distance setting in the menus or on a dial. Each manufacturer calls it something different
Also many cameras without manual aperture and shutter settings have a long exposure mode where you can specify exposure time in increments often up to 15 seconds or more. This may work but should take the camera out of auto ISO mode and select the lowest ISO option. This will result in an image with less noise. The small sensors in point and shoot cameras have more image noise than those in bigger cameras. Not really noticeable in daylight images but it will really show up in long exposures in dark conditions
They are basically two spotting scopes bolted together. Very wide openings, wider than beer cans, ect. I use them regularly to take peeks at planets when we go out to the mountains at night and I get a nice deep starfield backdrop I dont get by eye.
Maybe 100mm objective lens or a bit more Perfect.
CraigSmith -- always enjoy your photos and commentary on photography. My wife gave me a Nikon kit last Christmas which includes a D3500 body, a regular 18-55mm lens and a 70-300mm lens. Fairly intuitive for taking basic shots -- but the use of manual settings is a bit more challenging for me. (I find the online owners manual fairly limited). Your post has inspired me to bust out the Nikon and see what I might capture in the night sky. (I picked up David Busch's "Guide to Digital SLR Photography, Nikon D3500. Fairly dense with technical stuff!). Anyway, we'll see how it goes...
Excellent camera. Better sensor than my D7100 which would be 2 steps up in Nikon’s lineup ( equivalent today is D7500). The more expensive cameras have more buttons which allows quicker changes without having to get into the menu system.
I could set the D3500 up in about 2 minutes to shoot the comet without the manual but I’m familiar with the Nikon menu system and functions.
You will want to use the 70-300 lens
You will want to put then lens in manual focus mode. I think you have to do that in menus with that lens and body.
Put camera exposure mode to manual - M on the dial.
Set lens zoom to 70 and set aperture to smallest number. I think 4.5 for that kit lens. At 300mm the smallest aperture number is 6.3 but the camera will automatically adjust as you zoom in and out.
I think you set aperture by using the control wheel (thin wheel with teeth top back right about where your thumb would go - not the bigger dial with MASP and other indicators on it) and a button on top with a +- or something like that on it.
You will want to turn of Auto ISO off in the menu system
Set ISO to 400 or 800 - again in the menu system if you haven’t programmed one of the programmable buttons to do this
Set into self timer mode. If it allows delay time to be set pick 5 or 10 seconds. This allows vibrations from triggering the shutter release to die down.
Mount camera on tripod.
Manually focus on distant object best as you can
Set shutter speed using control wheel. The big numbers are fractions of a second. When you get down to 1second you will see the seconds indicator - “ - next to the number. So you will see in the viewfinder and/or back screen 1”, 2”, etc. if you just see 2 without the tick marks that is 1/2 second.
Try your first shots at 100 to 135mm to see what you capture and make it easier to compose initially. As you get confidence zoom out.
Try different exposures to see what works.
Don’t forget the sky moves - well actually the earth does - so you need to reframe occasionally.
The D3500 has an instructional guide mode that may help. I have never used it.
There are more settings that can be made but skip those for now.
Camera manuals are notoriously poor and confusing but everything above is covered in there. That guide you purchased should be more helpful.
When done, undo the settings you just made. If needed use the two button reset to go back to factory defaults.
If you use the 18-55 lens for wide angle shot you will want to go into menu system to turn of Vibration Reduction (VR). It can mess with images shot from a tripod. The 70-300 that comes with that kit doesn’t have VR ( I’m assuming your wife gifted you the kit)
Awesome! Thanks much for the detailed info. I'm going to try again tonight. (Last night was a bust. Need a better vantage spot).
I have the D5600 and a Nikon 300mm with VR - tripod is just ok - so I should be able to capture it - but sometimes it is nice to just look at it and not take a photo.
So many of my kids events I was so busy photographing or recording that I basically missed them.