August 31, 2014, 04:42:14 AM

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Messages - 20Dave

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On number one the bird appears larger because it is framed tighter by the fact that the sensor and is using a smaller percentage of what comes into the lens.

But when I zoom to 100% on my computer monitor, 1 pixel on the monitor = 1 pixel on the camera, right? If yes, it seems that the sensor size would be irrelevant, only the pixel density. I would think that your statement is applicable to #3, not #1. Or am I missing something?

Sorry for another thread on this, but it seems to me that there are different definitions of what "extra reach" means as it relates to cropped sensors. For my own education/clarification, this is what I think, but I would welcome any corrections. These are imaginary scenarios to help define the parameters.

1) Extra reach = "I take two pictures of a bird from the same spot on my porch, one with a 7D, one with a 5DIII, both of them with the same lens. When I pixel peep on my computer at 100% resolution, my 7D "zooms in" further, i.e. the bird appears larger. (I'm ignoring how "good" the bird looks in either shot.) In this case, the larger image of the bird on my computer monitor has nothing to do with the 1.6 crop factor; rather, it has everything to do with the increased pixel density of the 7D as compared to the 5D3.

2) Extra reach = "I'm going to frame a picture of some non-moving subject in my viewfinder exactly as I want to print it off (using the Quick Print button, of course). So, I take the photo from X feet away from the subject using the 7D, and I take a picture of the same subject with the 5D3 from X/1.6 feet away i.e. move in closer. In this case, the "extra reach" of the 7D in terms of where I need to stand to properly frame the photo has everything to do with the 1.6x crop factor of the sensor.  Also in this case, I believe that the background will be more blurred with the 5D3, but I don't know if that has anything to do with sensor size or if it's just because I'm 1.6x closer to the subject with the 5D3.

3) Extra reach = "I'm going to take a picture of a shy bird, so I'll stay 40 feet away when taking the photos. I want to print an 8x10 photo with the bird being the same size in the framed picture on both photos. If the bird happens to be the right size in my frame using the 7D, I'll need to crop the photo that I take with the 5D3. The amount that I need to crop out (as a percentage) is based on the 1.6 crop factor of the sensor.

One other point for scenario 3 - if I was hoping for the same resolution in both photos, then the FF sensor would need to have 1.6 * 1.6 (i.e. 2.56x) more pixels. I don't know the numbers offhand, but if the 7D happend to have a 20 MP sensor, then a FF sensor would need to have a 51.2 MP sensor for me to crop it down to the APS-C size image and still offer the same resolution (pixel density) as the 20 MP cropped sensor.

I know that I've ignored important variables like how well I can hand-hold the camera (shaky hands will be amplified in the 7D), AF accuracy, keeper rate, lens resolving power, etc. I'm just trying to clarify how "extra reach" comes into play with APS-C cameras.

Again, corrections to my assertions are welcome, as are use cases that I missed.


Canon General / Re: A Rundown of EOS 7D Mark II Information
« on: August 16, 2014, 04:28:32 PM »
  Only time will tell, but its these little snippets that keep us coming here, right?  :o

It feels like two weeks before the NFL draft, with CR playing the part of Mel Kiper.

Kiper: "Well it's a lock that Canon will be drafting a replacement for the aging 7D in the first round. It looked like a mini-1DX at the combine, and hopefully that will translate into production."
McShay: "That's probably true. However, although everyone expects a 100-400 in the second round, I wouldn't be surprised to see them to pass like they did for the last couple of years. Maybe a surprise like a 180 macro with IS, just to create a splash."

And like on sports forums, there is as much (if not more) angst about what might happen than about what actually does happen.

I'm just happy that I bought my 5D3 nearly two years ago to replace my aging 20D rather than waiting for the 7D2 (which I was strongly considering). When the 7D2 (or whatever they call it) finally comes out, it might be the best fit for my uses, but I'm more than happy enough with my current camera so I'm not really interested in moving over. As for the 100-400, if that comes out and if it has similar performance like the 70-200 II, that might be a different story.

Animal Kingdom / Re: Show your Bird Portraits
« on: July 31, 2014, 07:41:21 PM »
Here's one of mine from last fall.

EOS Bodies / Re: One other hoped-for feature on the 7D2
« on: July 29, 2014, 02:56:52 PM »
How does the 1DX do it?

In the pdf you can find on page 28 a possible solution for assigning EC to a button.

Be patient: it will take some time to open this pdf.

They assign EC to the set button. Afterwards you can change easily the EC by pushing SET and turning the mail dial.

I just found that the 5DIII can fairly quickly change ISO as well (p. 327 of the manual), but it is disabled by default. You have to hold down the set button while turning the small dial next to the shutter button. You can't go into auto-ISO with this method, but you can go out of it and adjust the ISO while looking in the viewfinder. Not as straightforward as EC, but I'll give this a try.


EOS Bodies / Re: One other hoped-for feature on the 7D2
« on: July 28, 2014, 11:20:33 PM »
On my 5DIII this just works.  What body are you using?
I have a 5DIII also. Sorry for my poorly worded initial post as well as going offline for 8 hours after posting (post-and-run...).

I think that eventually people understood what I was getting at. I know that I can shoot in M mode with a fixed shutter, fixed f/stop, and auto-ISO. However, EC isn't an option in that setting. I double-checked the user manual and it says that "exposure compensation can be set in the P/Tv/Av shooting modes". All that I'm hoping for in upcoming cameras is to add M* to the supported modes for exposure compensation, where M* = M with auto-ISO enabled.

I guess that the thinking is that if you are in M, then the two dials would most often be used to adjust the shutter speed and the f/stop, so you run out of dials to adjust EC.

EOS Bodies / One other hoped-for feature on the 7D2
« on: July 28, 2014, 11:17:19 AM »
In order to keep my shutter speed fast (for my 400mm lens without IS) and an F-stop a little less than wide open for a greater depth of field, I need to set the camera to manual. With those two settings fixed, in order to adjust the exposure, I need to manually adjust the ISO.

With auto-ISO enabled, the Manual camera setting isn't really fully manual. It would be great if the camera allowed exposure compensation for the "not quite manual" setting where shutter and f/stop were fixed but ISO was automatic.  [BTW, let me know if this is already a feature and I missed it somehow.]

Any speculations on what *else* the lens could be if not the 100-400L successor?
Knowing my luck, it'll be another 400mm f/5.6 prime...

Actually, I'm praying for a 400mm f/5.6 prime with IS, but I'm expecting a new 100-400L. If it exceeds the quality of the current 400mm prime at 400mm, then that works for me.


Lenses / Re: Value Lens for birding
« on: April 21, 2014, 04:53:18 PM »
I really wish they would make a new version of this lens with IS, even at a few hundred more I suspect it would sell well, since the next thing up the ladder is the 400 f4 DO, which is a lot pricier.

Just a SWAG based on the price increase between the 70-200 MkI and MkII, I'm guessing that any new 400mm IS (whether a prime or 100ish-400 zoom) will be in the $3k range. Still more affordable than a DO, but with pent up demand for such a lens, I think that they could get a fair revenue stream even at that level.

Lenses / Re: Value Lens for birding
« on: April 21, 2014, 10:08:41 AM »
I shoot birds almost exclusively (hobbyist, not a pro). I have the 400 f/5.6 and a Kenko Pro 1.4x teleconverter on my 5DIII virtually all of the time. I've been very happy with it, but with two caveats:
1) I can't use AFMA with this setup. Fortunately, the focus has been good enough without needing to adjust it with my particular setup.
2) Being well into my second year with this setup, I am starting to long for IS. I have very shaky hands, so I need to set the shutter speed at or near 1/2000 for sharp images at the 640mm focal length. With the f/8 maximum aperture of this combo (and I prefer f/11 for a reasonable depth of field), that means that the ISO is usually well into the thousands unless it's a sunny day and not in the woods.

I think that the 400 is a great balance of price/performance, and it's actually the reason why I choose Canon rather than Nikon when I entered the DSLR world about 8 years ago (with a 20D). And if you really start getting into birding, I think that you'll find that you'll eventually want a 1.4x extender of some sort.

I'm really hoping for a new 400 with IS or a 100-400 Mark II sometime this year. At the same time I may upgrade to the Canon 1.4x to get AFMA. As a side note, I gave up waiting for the 7DII last winter and splurged on a 5DIII. I have no regrets on that front, and will continue happily shooting with my current setup as I wait for the next batch of telephotos (that aren't in the $10k range).


EOS Bodies / Re: EOS 7D Mark II Announcement in Q2 of 2014 [CR1]
« on: February 27, 2014, 06:16:48 PM »
Hurry up already, Canon!!  I may have to break down and just get the 1DX if you don't  ;)
Joking aside, my 7d is feeling older and older the more I shoot with the 5d3.  I like the combo (7d,5d3), but... that 1DX rental has me craving something new.

I'm very glad that I bought a 5D3 a year ago rather than waiting for the immanent (at that time) 7D2.

EOS Bodies / Re: EOS 7D Mark II Announcement in Q2 of 2014 [CR1]
« on: February 27, 2014, 05:33:26 PM »
So you're saying there's a chance...   ???

Animal Kingdom / Re: BIRD IN FLIGHT ONLY -- share your BIF photos here
« on: February 20, 2014, 12:14:28 AM »
Here are more Brants wintering along the RI coast.


EOS Bodies / Re: sotchi - canon prototypes
« on: February 15, 2014, 08:57:41 PM »
I perused the enormous panoramic shot of a World Series game just to see if anyone on the field level used the 34# Sigma 200-500mm f/2.8 zoom lens, and sure enough, some photographer had one. It is a distinctive lens in olive drab , looks a little like an overgrown RPG launcher.

i guess everyone here knows the hulkma. ;)

and yes i spoted one of them at sotchi too.

That's a pocket camera ;D. I've actually had the chance to work with a Sony XIS camera. It mostly a video camera but takes stills in a panorama mode to capture up to 270 degree view. And the specification is accurate when it says "less than 90 lb 6 oz", as I've had to move one of these suckers myself  :o .


Animal Kingdom / Re: BIRD IN FLIGHT ONLY -- share your BIF photos here
« on: February 15, 2014, 08:39:14 PM »
Here are a few recent ones of mine. I would have said that one was a flock of Canadian Geese, but their wing speed seemed too fast. Sure enough, it is a flock of Brants, which I had never heard of prior to researching that photo. CCC welcome (the lighting is not good on the first two - too close to the middle of the day...). All shots were with a 5DIII and a 400 f/5.6 with a Kenko 1.4x teleconverter.


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