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Messages - comsense

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31
Lenses / Re: 100-400 f/4-5.6 or 200-400 f/4 "little brother"
« on: August 10, 2013, 01:05:09 PM »
You are comparing apple and oranges. 100-400 f/4-5.6 is the little brother you are talking about. The majority of cost of 200-400 f/4 is due to f/4 at 400 end. If you plan on keeping that, the brother won't be significantly littler. I would guess if it still zoom with IS, expect about $10K. You are expecting that to be priced like $1400 lens.  :o :o :o
It will benefit canon to have a cheap lens within reach of entry level hobbyist. And anything more than $2K (which means 400 end at f/5.6) is going to kill that goose.

32
EOS-M / Re: You Get What You Pay For - Warning for EOS M Adapter
« on: August 08, 2013, 12:20:06 PM »
This is specifically what I ordered:

Order Details
Order #105-9938622-8375460
Placed on Sunday, July 7, 2013
   Rainbowimag (AF Focus) Canon EOS EF & EFs lenses to Canon EOS M digital camera Adapter, replaces Canon Mount Adapter EF-EOS M
Electronics
Sold by SmithWebstore
   Facebook    Twitter    Pinterest
   $65.99
Item Subtotal:    $65.99
Shipping & Handling:    $4.65

Total Before Tax:    $70.64

Order Total:    $70.64

The top photo from Mount Spokane shows the one I bought, with the silver button which should release the lens.

I will try some more wiggling and forcing tonight.  If I don't succeed, I am going to take to Samy's repair counter tomorrow (I live in Los Angeles).

Thanks for the suggestions.
Save yourself some more pain. Return this and get Canon. I got Canon original last week for $85 + free shipping from Hong Kong like others. Why would you want to save $14 for a knockoff? You overpaid even for knockoff as I can get the same for $45 on eBay!!!!!
I buy knockoff's only when there in no risk to myself or my equipment and  they are cheap enough to write off after few uses, never at 80% of OEM. Make offer to several sellers on eBay. One of them accepted my $85 offer over price of $100.

33
Third Party Manufacturers / Re: Super fast exposure time - BBC News
« on: August 02, 2013, 08:42:26 PM »
Pretty sure you can use any light, since its quite literally capturing a photo of light. You just adjust the exposure to compensate for the amount of light like we already do.

Right, so at 1 billionth of the current max shutter speed of 1/8000 s, to 'just adjust the exposure to compensate for the amount of light like we already do,' you'd need to go 36 stops higher than ISO 100.  Know any cameras that can set ISO 6,871,947,673,600?   ::)
Actually you both are wrong. You cant use any light. You need femtosecond pulsed laser source to illuminate the scene.

Ok, but I was being facetious.   :)

FWIW, many years ago I used femtosecond laser time-resolved resonance Raman spectroscopy to study reaction intermediates of visual pigments (rhodopsin, etc.). Nd:YAG flashlamps, beamlines running across massive air tables decorated with mirrors and dichroics, fun times.  I currently use a femtosecond Ti:sapphire laser (pumped with a frequency-doubled Nd:YVO4 laser) in fluorescent imaging applications.
I could see your humor; just wanted to make it geeky accurate with hand holdable Ti:sapphire  ;D :'( ;D
Good to know you are spectroscopist and have used it; you can visualize very well what I mean.
Also, how many LP6 batteries would it take?
The around the corner image reconstruction from this group is pretty cool. Laser tech is developing so fast and people are already working on solid state femtosecond pulse lasers. If high pulse power is not required, its possible to have hand holdable version in near future. 

34
Third Party Manufacturers / Re: Super fast exposure time - BBC News
« on: August 02, 2013, 08:09:57 PM »


Interesting...sounds almost like a reverse ray-tracing rendering!
[/quote]
Final part is more like scanline rendering if you like computational graphics lingo. The maths for first part is quite old and solid, its just tech catching up. Google TCSPC (time correlated single photon counting). This is the principle behind extraction of time information.

35
Third Party Manufacturers / Re: Super fast exposure time - BBC News
« on: August 02, 2013, 07:03:59 PM »
Pretty sure you can use any light, since its quite literally capturing a photo of light. You just adjust the exposure to compensate for the amount of light like we already do.

Right, so at 1 billionth of the current max shutter speed of 1/8000 s, to 'just adjust the exposure to compensate for the amount of light like we already do,' you'd need to go 36 stops higher than ISO 100.  Know any cameras that can set ISO 6,871,947,673,600?   ::)
Actually you both are wrong. You cant use any light. You need femtosecond pulsed laser source to illuminate the scene. Then streak camera, PMT or other device is used to capture reflected pulses to create a probability distribution by acquiring millions of scans and calculate arrival time of photon (extract time information). Image is then calculated and integrated for whole scene using piezo-controlled mirrors. In short for people with non-technical background, repeated measurement of scene illuminated by femtosecond spaced pulses combined with maths is used to calculate the time information at a point/line. This is then calculated for all points/lines in scene to construct an image. So its takes quite a while to construct one super-fast timelapse (counterintuitive isnt it).

Small issues getting it into Canon 1DXXX:
1) You need at least two people to hold even simplest of femtosecond lasers
2) Its a two piece assembly with micrometer beam alinment on optical table; good luck with handholding
3) You need the scene to repeat millions of times. Like if you want a video of kid running, you will need the kid to run same path millions of times (this is only for time lapse imaging; does not apply to their around the corner imaging)
and many more but I am bored.
I am sure they will overcome these problems sometime in future!!!!
Source: I use the same camera at nanometer scale. So I collect images with nanometer spatial resolution and picosecond time resolution.

36
Lenses / Re: 24-70 II cracked focusing ring.
« on: July 25, 2013, 08:32:33 PM »
The thing is, the focus rubber is not glued at all. It can be easily pulled off. But it's your lens and you can decide what to do.
You are unnecessarily raking up an aggression. You are assuming that OP lacks DIY spirit or knowledge that rubber can be pulled off. If the item is still under warranty and canon would replace rubber for free, I see no reason to have either  band-aid fix of ugly glue or el-cheapo rubber. Esp if OP has time and patience.

37
“totally usable photosite count”

Which means the "75 MP" sensor is really a 25 MP sensor in terms of spatial resolution.
Its true only in terms of sensor architecture. In terms of image spacial resolution situation is far more complicated. While bayer and anti-aliasing filter leads to image spacial resolution loss in bayer sensors, its scattering of red photons in foveon. The reality is somewhere halfway for each. At the least, 25 MP foveon is going to be far superior to 25 MP bayer sensor in terms of spatial resolution of image.

38
Camera Body Gallery / Re: This sensor is holy
« on: July 17, 2013, 02:41:39 PM »
but i'm an atheist....

what should i do?

Keep up the good and level headed work.
I am an atheist myself. Spiritual though. I practise scotch and vodka - separately - unless it is a long island ;)
Are you sure you want to get into this huge and explosive religious dispute -
There is no whiskey in the most popular and widespread Long Island, New York version of LIIT (Long Island iced tea). A disputed origin 1920s LIIT from Long Island in Kingsport, Tennessee had Whiskey (TN whiskey though) and maple syrup.  You seems to favor TN over NY but snub it with Scotch :o

If it's Scotch then it isn't Whiskey, it's Whisky.   We put Whiskey in our cooking sauces.  We drink Whisky.
Oxford English Dictionary, Second Edition: "In modern trade usage, Scotch whisky and Irish whiskey are thus distinguished in spelling; whisky is the usual spelling in Britain and whiskey that in the U.S.
Aye, You are quite right. But -ey is usual spelling this side of Atlantic and auto-corrected so!!!
And I did not anticipate another religious war i.e. over whisky/ey

39
Camera Body Gallery / Re: This sensor is holy
« on: July 16, 2013, 06:38:43 PM »
but i'm an atheist....

what should i do?

Keep up the good and level headed work.
I am an atheist myself. Spiritual though. I practise scotch and vodka - separately - unless it is a long island ;)
Are you sure you want to get into this huge and explosive religious dispute -
There is no whiskey in the most popular and widespread Long Island, New York version of LIIT (Long Island iced tea). A disputed origin 1920s LIIT from Long Island in Kingsport, Tennessee had Whiskey (TN whiskey though) and maple syrup.  You seems to favor TN over NY but snub it with Scotch :o

40
EOS-M / Re: Digital Rev quick 2.0.2 autofocus speed test
« on: July 15, 2013, 03:14:23 PM »
Why I bought M:
1. $299 - for crop sensor + 22mm f2 prime. Can't beat that
2. Will be used for still shooting

Don't expect too much from $299 camera. Faster focus will be in next version(s). Start your saving NOW, you looking @ $1300-$1500ish.
I expect EOS M II to catch up with the competition and not beat it. If they price at 1300-1500, it would be awesome. So, all one need to do is just sit tight and wait retailers to offload their unsold stock for $300 again.
Fortunately, Fan boys don't generate profits for Canon, otherwise all their products would be priced 5X higher.

41
EOS-M / Re: How do you carry your EOS-M?
« on: July 15, 2013, 03:03:05 PM »
Fits perfectly in my Lowepro Dashpoint 20, which is how I carry it when I'm on the go.
Thanks neuro, got one myself and it is indeed the best for M+22

42
EOS-M / Re: My Eos M at work...
« on: July 15, 2013, 02:55:35 PM »
It gets bad press because people still think something in that price range is supposed to perform as good or better than something that sells for up to 5x more. I actually want one. Eos m plus adapter is the best backup camera for field work that you can buy right now ^^

Not really..i never expected it to match something 5x more expensive. The fact i had so much trouble with it not because it couldn't keep with with the 5D..the fact is, it couldn't even keep up with the Nex5N or the FujiX100s. I have friends shooting the same event using those cameras while i was using the M...they has alot more luck than i did and that's what got me disappointed in it. So i borrowed their cameras and true enough..they were way better.
the only reason why i bought it is because i could use my canon glass and also because it was cheap....but if given a choice, i would've gone with a nex anyday after that weekend of shooting and deleting over 80% of my photos because of wrong exposure or bad focusing...
I had the same experience. It is really a great camera for prepared stills and studios. If you want to shoot something unexpectedly or something moving, it sucks. The time to capture shots (including time to AF) and time between shots is unacceptable for camera of this 'class'. I wonder how bad it was before firmware update??? Its poor sales are completely justified. I believe at $300 its still a good deal but not the 'deal of the year' some people are claiming. 
Fan boys on other thread were not happy...... ;D ;D ;D

43
EOS-M / Re: Just got my EOS-M! First impressions...
« on: July 14, 2013, 03:03:49 PM »
Oh boy, people do like to argue here tirelessly and most of the time pointlessly...
Despite my clarifying that M is good (esp for 300 bucks) and I am NOT comparing it with iphone the debate still rages on. Let me try one last time:
M is a good camera and can take good photos. However, it does not meet MY reasonable expectations of a product in this class. And neuro thanks for your useful post but I am not expecting M to perform like 1DX.
Rather, you gave me a good clue. I was confused between 5DIII and 1DX (I can easily afford 1DX so money is not the factor). But after comparing the specs, I came to conclusion that for me extra cash spent on 1DX is not getting me anything that is important for what I shoot. And I am really happy with 5DIII. It met all my reasonable expectations 100%. I have no complains about it being overpriced or I should have got 1DX functions with it or GPS/WiFi etc etc.
Even though M was sold at $4-500 range, my $4-500 expectations were not met.
So all I was saying is that my 'Camry' is guzzling gas like 'Hummer' not that I expect it to be 'Prius'!!!!
And before someone else comes and says that is is a great camera and can take good pictures, I am saying in advance, I agree. 

44
EOS-M / Re: Just got my EOS-M! First impressions...
« on: July 13, 2013, 03:35:13 AM »
Both of you need to read my post again.  For sake of time and sanity I am not going to explain to you that 4fps does not compensate for long lag time between the shots and enable capture something at the very exact moment you want.

I spent 3 hours shooting street the first night I got my M. Capturing the moment I wanted just involved pre-focusing and holding the shutter half way until the moment came. No different from capturing the moment with an all manual camera. If you're focused there's hardly any release lag.

You might miss a true surprise moment due to AF. But then again, you will with most cameras. I had one such moment that night (a kid running by me) and I would have needed my 7D to nail it.

I do wish Canon would make this easier on us with some additional options. Let me AF off the record button. And touch to focus (instead of touch to shoot). Make manual focusing useful (peaking + much shorter throw). And give me a DoF distance scale on screen. Give us that and the "moment" argument is completely moot.

Even without that, you can work with the camera and be ready.

Quote
1) Your kid doing something cute which you want to capture almost instantly.

I'm not going to lie and claim that the M is ideal for tracking kids running around. Neither is the iPhone, most P&S bodies, or a lot of mirrorless bodies. Kids can be as challenging as sports so grab a sports orientated DSLR for kids.

When kids are sitting down and being cute, I see no reason why you can't anticipate and capture the peak moment with the M. If I can do it with a street drummer....

Quote
2) Some event/occurance you saw while driving or stopped at light (as a passenger of course) that you want to record instantly.

You have a lot of those that are over and done with in the time it takes the M to AF? I know there's a lag, but come on....

Quote
Don't get fixated on pixel density and fps and all and swear that you would never touch iPhone. There will be time when it will be faster (note faster is not equal to better) for you to whip iPhone to take a shot while accessing M, switching on and fumbling with its quirks will actually miss the moment.

Playing right now at my desk...my iPhone has more AF/release lag then my M. On the M I'm using single point AF with the 22mm f/2. Haven't even really tried the others. Perhaps you're seeing more lag with the other modes?
Its good that it works for your personal style and photography needs. No one can argue with that. But that does not make the camera responsive/faster if others need it that way.
I like to watch my frame constantly and click at right moment. Sometime I want to click again after a sec because scene changed for better, but I find M unresponsive. (esp when shooting RAW). My kid changes the face expression by the time this focuses and captures the shot (not always but annoyingly more than I want). I like the camera otherwise. Since, I am not a fanatic fanboy, I am open to reasonable criticism.

45
I did these tests this evening. I was as careful as possible to keep room lighting the same for each shot.

See the thread about "50mm lenses that don't suck wide-open", which made me get off my butt and do these tests.

Note that the aim for these tests was only to compare lens brightnesses (T-stop) and bokeh, with all lenses wide-open.
The scene is too dark to determine relative sharpnesses.

I tested the Canon 50mm f/1.4 wide-open, both connected and NOT CONNECTED electronically, by rotating lens in body while holding the lens-release button down. Mechanically it is still completely mounted, but the camera cannot communicate with the lens, so does not know what it is, so it cannot "decide" to sneakily increase the ISO.

Canon 5D Mark 3
Manual
t=1/15s, ISO400 (nominal)

Focus was on the same point on the lantern, using live view, magnified x10.


RESULTS:

Dude was right. The "CONNECTED" Canon 50mm f/1.4 image is noticeably brighter, and I took the picture both ways, several times, and the results were completely repeatable. So it seems that the 5D3 DOES sneakily SEEM TO boost ISO without telling you, if it detects that the 50mm f/1.4 lens is connected. When I review the images on the camera, they all say ISO400.

Dude was also right that the Olympus 50mm f/1.2 is significantly brighter than the Canon 50mm f/1.4 wide-open, EVEN brighter than the "CONNECTED" image. That makes me feel slightly better about having dropped just shy of £400 on this (perfect, mint, unmarked) example of this lens, back in Jan. 2010!


Here's the album on FB:

https://www.facebook.com/media/set/?set=a.4505135767033.1073741834.1849695638&type=1&l=7e5db91bd2

Here are the files on Dropbox, including raw files:

https://www.dropbox.com/sh/rhtr3k0ru902sbr/yMKl0KWANf?lst

The tests I did were:

Zuiko (Olympus) 50mm f/1.8 - Dimmest, as expected

Zuiko 50mm f/1.4 Silvernose

Zuiko 50mm f/1.4 Non-Silvernose (later model) VERY SLIGHTLY brighter than Silvernose

Zuiko 55mm f/1.2 - Has the "biggest" bokeh / OOF blur. NOTE! This is a 55mm lens, not a 50mm one.

Zuiko 50mm f/1.2 This is the brightest of them all

Canon 50mm f/1.4 NOT CONNECTED, because lens was rotated to disengage electronic contacts

Canon 50mm f/1.4 CONNECTED - Should be same, but IS BRIGHTER
Curb your enthusiasm!!!!
You need to care of these things:
1) Put the metering off and shoot in M mode
2) Put the tape (super thin one) over contacts and click it all the way. Rotating changes lens light entry and image plane to sensor angles and could effect light reaching sensor and hence brightness (not a perfect control - you are comparing apple with oranges)
3) Capture 5-10 photos with each condition and take an average

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