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PF Photography Thread

by _Mayday_
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Andy Resnick
#1225
Apr27-12, 10:21 PM
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Got some excellent shots of the ISS (space station) during tonight's flyover. Easy-breezy: I set the exposure by Venus (magnitude -4.7 vs. ISS @ -2.4, so I doubled the ISO to compensate) 800/5.6, 1/500s ISO 250, no mirror lockup. Trivial to track- I took about 120 shots over 5 minutes. My card reader is at work, so I'll post a montage ASAP.
Andy Resnick
#1226
Apr30-12, 09:04 AM
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Here's the whole series, no processing other than cropping and white/black levels. Seeing conditions were... "not optimal". ISS came into view from the NW and traveled approximately at a constant 40 degree elevation angle down to the SE.



The moral of the story is: 1) *fast* shutter speeds are essential. 2) mirror lockup isn't needed, and 3) a good tripod head is required. Even though I was only slewing at ~ 3 degrees/second, I could not have done this without a gimbaled mount- I was tracking with one hand and remote triggering the camera with the other.
Andy Resnick
#1227
Apr30-12, 07:41 PM
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Here's a cleaner version- I individually adjusted each frame and deleted the 21 worst:



I can see how the ISS rotates as it passes; it starts out with the bright main truss on the backside, and then rotates into front view. It also appears that the station is executing a roll maneuver (with respect to me) during the pass, but that could be my imagination.

Here are some external timelapse videos from a camera mounted to the ISS with some hints as to what is moving when:

http://www.youtube.com/watch?v=kMLAQ4pvMmg
Andre
#1228
May7-12, 03:06 PM
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So just I got myself a Sigma 150-500 today. I did quite an elaborate research with on the shortlist also the Canon 100-400L (Turbo's lens) and the Canon 400mm F5.6L.

The Sigma won finally, due to the extended reach. As 400mm is hardly much of a gain compared to the 70-300. Maybe with tele extenders on the 400mm L, which has sufficient image quality for that, but it lacks the image stabilization.

I accepted the caveats of the Sigma, the weight and the soft image at full opening at maximum range. I tested that sort of randomly -not prepared- on these little bottles:



Oops, I did not spot that little dead bug at the time. I should have dusted first

But indeed it's soft full open as seen on this 100% crop on top:



But the bottom crop at F10 is pleasing enough to keep it. I think.
Topher925
#1229
May7-12, 03:48 PM
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That is one helluva lens. I was looking at buying a nice 400 or 500mm prime not to long ago for nature photography but couldn't bring myself to fork out that much dough so I bought a telescope and adapter instead (Orion ST80). Surprisingly good images for a hundred bucks but big, heavy, and difficult to use so now its only used for astrophotography.

I did recently get a sweet deal for a Pentax DA 70mm Limited. And while it doesn't have the reach of 500mm, 70mm is still not bad and its ridiculously sharp at f5.6 and beyond. Its so small and light it fits in my shirt pocket.

A shot with the 70mm at f2.4 ISO 200


100% Crop of above image
Andy Resnick
#1230
May8-12, 08:50 AM
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Quote Quote by Andre View Post
So just I got myself a Sigma 150-500 today. <snip>
Quote Quote by Topher925 View Post
<snip>
I did recently get a sweet deal for a Pentax DA 70mm Limited. And while it doesn't have the reach of 500mm, 70mm is still not bad and its ridiculously sharp at f5.6 and beyond. Its so small and light it fits in my shirt pocket.
<snip>
Yay! new toys! I put in for a new lens as well, we'll see how it does when I get it.
Ms Music
#1231
May8-12, 03:40 PM
P: 173
Quote Quote by Andre View Post
So just I got myself a Sigma 150-500 today.
I think I have that same lens, if not, one very similar. I may have to drag it out and play around with it and try to copy some of the stuff you do. I have barely touched it, but never was satisfied with its performance. And I didn't have the time to research it. I have always felt that A/ it doesn't work right, B/ my tripod isn't beefy enough for it, or C/ I too stoopid to use it correctly. I believe the correct answer is probably C.

Would you be willing to walk me through copying a few of your photos to see if I can truly eliminate option A and B?
Andre
#1232
May9-12, 02:15 AM
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Sure, happy to help out. I'll link to full size pix later today.

Here and here is the full line up of the long sigma's.

Obviously there are many reasons why the results may disappoint, then again you cannot expect the same quality from a budget 1K lens than the 10k lenses, especially the Canon 400mm II F2.8L is flat out sensational, but way to expensive for common sense. So I wasn't expecting a better result than the second crop in my previous post.

Anyway, compared to the result with the 100mm macro, there is still clearly quite some difference in quality.



the Sigma:



To elimate any possible factor that may degrade the picture, these were all made from a sturdy tripod obviously, Optical Stabilator off, and manual focus in life view, in which I can blow up the focus area. Then from life view (and hence locked up mirror) the picture is made using remote control, but a self timer would also work, elimating any vibration.
Andy Resnick
#1233
May9-12, 07:52 AM
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Interesting- is it just me, or is the color rendition different between the macro and tele? The 100mm seems to be more blue.
Andre
#1234
May9-12, 08:29 AM
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Quote Quote by Andy Resnick View Post
Interesting- is it just me, or is the color rendition different between the macro and tele? The 100mm seems to be more blue.
Sorry, Andy, I should have told that those pictures were not made at the same moment in time.
Ms Music
#1235
May9-12, 01:56 PM
P: 173
Quote Quote by Andre View Post
Sure, happy to help out.
Thank you very much!

So what would you like me to do? Photograph one thing with two lenses to compare (like you just did with the macro), or would you like me to try to copy your "Dead Bug On Glass" to compare to yours? I meant to look at the lens so that you would know exactly the differences between yours and mine (besides the fact that mine is probably at least 5 years old), but forgot before I had to leave this morning. Just let me know what is easiest for you to judge, and any set up parameters you would like me to use.

Thank you again! My trusted camera shop went out of business before I got the opportunity to talk to them about it, and I haven't found anything convenient to replace that shop.
Andre
#1236
May9-12, 02:37 PM
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Okay, so we should try and make photo's of the same subject with the same parameters (mainly distance).

So here is my idea, we take pix of AA batteries, seems to be a standard thing for photo testing. Brand isn't interesting, it's just that we know that they are the same size.

Next thing is to determine the magnification. 1:10 seems simple, that means that with 500mm distance to the subject is 5 meter and with 50mm it's 0.5 meter etc, but we have to add the focus distance to that. Actually that's not fully correct as Andy will be happy to point out, but it's a simple approximation, so for 500mm the distance to the sensor plane is 5.5 meters and for 50mm it would be 0,55 meters. So we can make several test shots with various apertures.

I will work on 500mm with F6.3 F8 and F11, and the 100mm at F8, it's sweet spot and I'll post the results in a bit.
Andre
#1237
May9-12, 04:02 PM
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I'm not altogether happy with the results so far, but this is something made with the 100mm at F8



If you just make something like that, I'll get similar pix with the 500mm tomorrow.
Ms Music
#1238
May9-12, 04:09 PM
P: 173
Remember, I haven't taken any photography lessons. I tried learning from the manual, but that was about the time that my memory decided to fail me. So if you get too technical......

Are the parameters something you can check with the EXIF data? (I think that is what it is called) Then you can correct my homework. I have had to resort back to plain old point and shoot.

Also, realize that free time is something I have little of. I will do my best to do what you want me to within a decent time frame. Just a warning!
Andre
#1239
May9-12, 04:18 PM
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Don't worry, just put a couple of batteries in the picture, roughly like that, using the TLAR* method and show some 100% crops and I will try to match that as close as possible.

Oh and please reveal your type of camera.


* TLAR = That Looks About Right
Andre
#1240
May9-12, 04:56 PM
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Meanwhile I went to the lake to test the long tube a bit for action and reality. All shots reduced to 20%. No cropping.



Those coots can really fight.







100% crop of the last:

Ms Music
#1241
May9-12, 05:17 PM
P: 173
Quote Quote by Andre View Post
* TLAR = That Looks About Right
LOL!

Ok, you're on. I will see how quickly I can get some batteries back to you. Just no fighting coots. I can't match that!

Oh hey..... Just had a thought as I was about to click to post. How do I post the full size image? I think my photo sharing site that I use for posting on the internet shrinks them, and I have never tried PMing photos to know how that works. Should I email them to you???
Andre
#1242
May10-12, 04:01 AM
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Yes email is okay. Also a possibility is installing a dropbox, which makes it easy to share files. Here are some of mine in full size:

http://dl.dropbox.com/u/22026080/IMG_9916.jpg
http://dl.dropbox.com/u/22026080/IMG_2379hdn.JPG
http://dl.dropbox.com/u/22026080/ver...27_vlinder.jpg


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