Tuesday, April 19, 2016

70-200mm f/2.8 Same Lens for Sport Photography and Whirlpool Galaxy

I'm so pleased the same lenses work out well for both sport photography and night sky photography, because those are the two kinds of photography I like to do. Recently, I was able to double dip a rental from BorrowLenses.com. I had been thinking about borrowing a lens for a while, but I didn't like the idea of possibly booking something and having overcast skies.

Side note: Use this referral link to get $20 off at BorrowLenses.com when you spend $99+ and I'll also earn $20 off my next rental, it's a win-win!

I finally pulled the trigger when I had the opportunity to do some basketball photography to help out Campus Recreation with their intramural championships - so I had a specific date and time that my lens would be needed, and then I would just hope for clear skies sometime within that same week.

I went with the Canon 70-200 f/2.8 without image stabilization (to save a buck), I got the protection plan and it came to about $100 after shipping.

canon 70-200 on telescope mountcanon 70-200 on telescope mount


Turns out I had excellent night sky conditions all week long, but I was so swamped at work I only got out one night. It also turns out that this time of year is great for basketball championships but not so great for bright deep sky objects. Orion sets right after sunset, and Andromeda isn't very high by sunrise. I'd have to find a suitable target, but more on that later...

My lens arrived right on schedule and was in a sturdy box. I learned I was supposed to send it back in the same box at the end of the week, and it came with a UPS shipping label inside for the return trip.

borrow lens package70-200 lens on tripod

Get $20 off at BorrowLenses.com with this referral link if you spend $99+ and I'll also get $20 off my next rental :) k thanks now back to the blog post!

This lens took a little getting used to - first of all, the casing is a fixed dimension so all the zooming happens inside the structure. Okay I probably could have described that better. There's no big long thing that comes out when you zoom in, it stays the same size. The lens was so heavy duty it came with a tripod collar to mount it over the center of gravity.

large lens hood
Lens hood, not only does it make the lens look even bigger and super sweet, it also helped keep away the dew a bit longer for night sky photos

canon ef 70-200

canon uv filter
UV filter - still not sure how to use these things

canon 1.5m to infinity switch
I had to look up the 1.5m to infinity and 3m to infinity switch on the lens. It helps you focus faster if you tell the lens that you never expect your subject to be closer than 3 meters.
When I was doing indoor sport photography, at first I wasn't all that impressed. My LCD preview looked okay, and I still had to crank the ISO up to 800-1600 range to get a fast enough shot. This seemed slightly annoying since I paid $100 just to have a faster lens. Then when I compared the photos to my pics from last year, there was no comparison. It was CLEARLY better, and I must have remembered incorrectly because my photos from last year had tons of grain and maxed out ISO at 6400 and even 12800.

f/2.8 sport photography
Canon T5i single frame f/2.8, 1/640 sec, 100mm, ISO 1600

basketball foul
Canon T5i single frame f/2.8, 1/640 sec, 100mm, ISO 1600

basketball creative commons
Canon T5i single frame f/2.8, 1/640 sec, 70mm, ISO 1600

slam dunk creative commons
Canon T5i single frame f/2.8, 1/640 sec, 98mm, ISO 1600
So I took 1700 photos and ended up with 200 or so pretty cool shots, and maybe 10 'wow' shots. It's my annual sport photography crash course haha, but it's fun. The students love feeling like all-stars and I think they set the pics as their Facebook profile photos for a while.

Okay, let's go from the indoor basketball arena to the night sky - can the Canon 70-200mm f/2.8 do both? In short, yes.

It took a while to find a target, but after seeing the Whirlpool Galaxy (M51) at 200mm, I realized it was large enough to actually see and would be a fun deep sky object to try, although I'd never imaged it before.

It was very easy to locate, to the right of famous double star Mizar and Alcor in the handle of the Big Dipper rising in the east. Like I said, not much else was up this time of the year within reach of my lens.

take flat frames with monitor
I actually took flat frames! That's how you can tell I really tried on this one...
m51 whirlpool galaxy dslr 200mm
Canon T5i stack of 145 sub, 30 dark, 26 bias, 15 flats at ISO 800, 200mm, 13 sec, f/2.8
m51 whirlpool galaxy dslr
Tight crop of above photo edited in Instagram (contrast, structure, sharpness)
Quick side note here about flat frames, this lens produced a really weird gradient pattern that was horizontal bars instead of a circular hot spot in the center. Is that weird?

flat frame
Flat frame from 70-200 f/2.8 lens looks weird. Also, see the image above, Deep Sky Stacker didn't really remove the gradient bars even with these flats, so what gives?

Wednesday, March 16, 2016

Mars in Scorpio March 2016

The red planet Mars is hiding in Scorpio this morning, just 10 arc minutes from the 2.6 magnitude star Acrab (β1 Sco). The red light gives it away. It was a windy morning but the clouds and the dark blue sky background made a cool effect.

The high ISO kinda ruins the color of Mars, so there is one at ISO 800 also, but then you can't see as many background stars.

mars march 2016
Single shot Canon T5i, ISO 3200, 300mm, f/5.6, 1.3 sec

mars march 2016
Single shot Canon T5i, ISO 800, 300mm, f/5.6, 1 sec

mars and acrab star
Single shot Canon T5i, ISO 3200, 300mm, f/5.6, 1.3 sec

Sunday, March 13, 2016

Canon T5i Control with Computer via USB Setup and Moon Photo

I've been slow to get around to this, after figuring out how to install EOS Utility without a CD on my laptop and realizing I could control my Canon T5i from my computer using a USB and actually shoot from my laptop. It's cloudy again tonight, but my 6 foot USB arrived in the mail so I wanted to test it out. My camera uses USB A to mini-B (not micro B like an Android phone, and not a regular B like a printer, but a mini-B).

laptop connected to camera with usb moon photo
6 foot cable lets my camera stand outside while I sit at the kitchen table

My original theory was that I would have finer control of manual focus using the EOS Utility software to make little tiny incremental changes. However, even the fine focus arrow seems to shift or stick and jump a little (could be my kit telephoto lens), but using my live focus technique I'm actually able to achieve similar results.

I think where this will really come in handy is with solar photography, because I'm unable to touch the manual focus while my DIY solar filter is over the lens. Being able to manually adjust the focus via my laptop would be a big help to focus in on those hard to see sun spots.

amazon basics usb a to mini b
Inexpensive Amazon Basics 6 foot long USB A to Mini B

It's hard to tell whether or not the single frame is better than what I get with autofocus on the moon. The moon is very hard to shoot with manual focus because the craters don't give the same feedback as a star. By that I mean when you focus on a star the goal is to get the dot as small as possible to know that you are in correct focus. With the moon, there's no absolute way to tell on a tiny LCD screen on the back of the camera - so shooting the moon might actually be better with the camera paired to the laptop to look for incremental improvements.

eos utility moon
Single frame desaturated but otherwise straight from the camera, 300mm, 1/160 sec, f/8, ISO 100
Not bad at all for a single frame, considering I was shooting between clouds too. Some better seeing and this might be a way to increase my moon quality without upping my lenses. Below is the final photo, stack of 3 frames with the usual post processing. I actually had to Google my high pass method to remind myself - has it really been that long??

eos utility moon
Stack of 3 frames, high pass layer in Photoshop

Sunday, January 31, 2016

Quick Winter Sky iPhone Photo

The iPhone can indeed do wide field night sky photos, like this one of the popular stretch of sky from Sirius to the Pleiades. The stars are slightly out of focus, which actually makes them look larger and easier to see - so it's not a bad effect. This photo was taken with NightCap Pro using long exposure mode. Doing a 1/2 second exposure helps reduce the background noise because I believe NightCap is averaging the pixels to clean it up a bit.

iphone 6 star photos

iphone 6 star photos
iPhone photo f/2.2, 1/2 sec, ISO 4000, 4mm

Thursday, January 28, 2016

Winter Hexagon Star Color Comparison

The Winter Hexagon or Winter Circle is an asterism (not an official constellation) that takes up a huge portion of the southern sky in winter with some of the brightest stars (including the brightest Sirius). You really can't miss it! As the hexagon moves across the sky through the season, it becomes the Spring Arch setting in the west at dusk.

Did you know the human eye can detect the temperature of stars? Amazing! We know that cool stars radiate and emit energy in the red and infrared regions of the electromagnetic spectrum and so they appear red or orange. Likewise, hot stars appear white or blue because they radiate their energy in the blue and ultra-violet wavelengths.

Using the same technique from a previous color comparison, I wanated to look at the entire Winter Hexagon. I also used the same exposure settings to keep everything constant, so the difference in brightness is also relative to the star's perceived brightness to us (Sirius is clearly the brightest). This makes it a little harder to determine color, because some of the stars are dimmer, but it's clear at least that there is a variety of color out there in this popular region of the sky.

I arranged them in this composite photo to show their position in the hexagon. It looks like a jewel box of beautiful colored orbs or marbles. This was fun and easy to put together. I feel like trying it again with different exposures to hold the brightness constant and then trying to organize them from coolest to hottest. Do you think you could? Which one looks the most blue?

winter hexagon star colors
Composite out of focus stars from the Winter Hexagon in their relative positions, all taken at 300mm, f/5.6, 1 sec, ISO 200
winter circle star colors
Winter Circle star colors with labels

It looks like last time I used ISO 800 and 1.3 sec exposures, which would have blown out Sirius for comparison but made Rigel brighter blue so it's easier to see. I bet if I looked at the histogram instead and just focused on getting that centered for each star I could get a good color comparison while holding brightness constant (or at least not washing anything out to pure white).
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