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Messages - neuroanatomist

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Lenses / Re: STEPUP / DOWN rings
« on: January 22, 2013, 02:34:09 PM »
Here's the B+W 67→77mm Step-up Ring that I use (I also have the 72→77mm ring).

As for filter wrenches, I use the Polaroid ones, ordered from Adorama (link).  B&H's, the Adorama-branded ones, and my local shop all have 62-77mm sets (and smaller) - the Polaroid ones are 62-86mm, which I need since I have 82mm filters.

The short answer is that they don't translate.  Guide number factors in distance and is affected by the zoom head on the flash (i.e. the 580 and 600 flashes have the same light output, but the GN of the 600 is rated higher because the head zooms to 200mm, while the 580's zoom only to 105mm.  Watt-seconds ignores distance, and furthermore, the actual useful output of a monolight is determined by modifiers (e.g. the angular coverage of the reflector).

But, for comparison purposes, most estimates put the output of a 580EX II as equivalent to about 60-80 watt-seconds.

Lenses / Re: STEPUP / DOWN rings
« on: January 22, 2013, 02:14:04 PM »
They're fine for what they are, IMO.  But, I'd pick the size(s) that I need to go in one step, rather than mulitple steps - i.e., to use my 77mm CPL on a 100L (67mm threads), I use a 67→77mm ring, as opposed to the two rings (67→72 + 72→77) you'd need with the set you linked.  Getting the filter as close to the front element as possible is preferable. 

Two 'problems' with step-up rings to be aware of - 1) they often (but not always) preclude the use of a lens hood, and 2) just like stacking filters, they can become stuck together.  I use B+W adapter rings - they're brass instead of aluminum, which makes them less likely to bind up, but I still carry a set of filter wrenches (if you use filters, that's a $5 accessory worth keeping in every camera bag!).

EOS Bodies - For Stills / Re: ISO 50
« on: January 22, 2013, 02:01:13 PM »
@TheSuede, agreed - and may I add, I'd love to see such performance (very low read noise at base ISO) from a Canon sensor!

EOS Bodies - For Stills / Re: ISO 50
« on: January 22, 2013, 11:50:06 AM »
This thread just shows how much of us could really use a "True" ISO 50 in DSLR's. I'd like one canon and perhaps they will be the first with the new 1Dxs.

The problem is that there's no free lunch.  A "true" ISO 50 would mean a lower base ISO, meaning that to achieve higher ISOs, even more amplification would be needed - meaning more high ISO noise.  Usually, if ISO 100 is not low enough, one stop more is insufficient, at least in terms of shutter speed.  The waterfall example posted earlier at ISO 50 and 5 s exposure required f/18 to get there - personally, I'd have preferred to shoot that at f/9 and ISO 100 with a 3-stop ND.

EOS Bodies / Re: EOS-1D X Firmware Specifcations
« on: January 22, 2013, 11:42:56 AM »
I am very happy with my 1Dx too (I got mine since August, one of the first units available in Europe) but I hate the Canon firmware update politics.

I hear you, but at the same time, they seem to have been getting better.  Previously, expecting Canon to add a meaningful feature via firmware update was a pretty hope - they had done so, but only rarely (e.g. 5DII video features).  But more recently, they added many nice features to the 7D (Auto ISO limits, etc.), added f/8 AF to the 1D X (although one could argue it should have been there from the start), etc.  So while not ideal, it seems to be better than before.

PowerShot / Re: Advice on P&S
« on: January 22, 2013, 11:19:52 AM »
I initially thought of the SX50 also, but that was outside of her price range.  She has found a used SX40 online that I think she wants to purchase.  It doesn't quite have the range of the SX50, but it also comes with an external flash and stays within her budget.

Makes sense.  Personally, shooting RAW is one of my criteria (the SX50 does, the SX40 does not, AFAIK), but it's certainly not important to everyone. 

I think if she really wants to shoot birds, an S100 or G-series won't be nearly long enough.

EOS Bodies / Re: EOS-1D X Firmware Specifcations
« on: January 22, 2013, 10:53:16 AM »
...the 1DX a 7000 bucks camera is the ugly sister...

Sorry to hear that you're dissatisfied with your 1D X.  You do have a 1D X, right?   ::)

Personally, I'm quite happy with mine...

EOS Bodies / Re: EOS-1D X Firmware Specifcations
« on: January 22, 2013, 10:36:13 AM »
Ok, well that clears up the mystery. 

Can't say I've ever accidentally changed the image size, but that may be because I have that button set to use the main LCD (not the small one), so the first press of the button goes to Record func and another press is needed to set image size, plus the large LCD display makes it immediately obvious that I've pressed the button. 

PowerShot / Re: Advice on P&S
« on: January 22, 2013, 10:20:05 AM »
I'd have a look at the SX50 HS (review).  It's a bit over the price stated, but meets the needs - long zoom, decent low light, manual controls, and shoots RAW (if your friend wants to put time into post processing).

Else, consider an S100 - large sensor for a P&S, decent in low light, pocketable (but only 120mm FF-equivalent).

Lighting / Re: Canon ST-E3-RT Mark II???
« on: January 22, 2013, 10:13:27 AM »
The ST-E3-RT is quite new.  Canon would have considered whether to include an AF assist lamp or not in the replacement for the ST-E2, and clearly they decided not to include that feature.  I would not expect them to change their minds any time soon.  If you need AF assist and RT control for remote flashes, you need to buy a 600EX-RT (and I'm sure that was part of Canon's motivation for leaving the AF assist out of the ST-E3).

EOS Bodies / Re: Yet Another 5D vs 7D Question
« on: January 22, 2013, 10:10:49 AM »
Quite a while back, I formally tested the 5DII vs. 7D, and came to the conclusion that there was no significant IQ difference between an image taken with the 7D and an image taken from the same distance with the same lens (100L) on the 5DII, then cropped to the FoV of the 7D.  The only difference was that the 7D image was 18 MP, and the 5DII image was just over 8 MP - so, if 8 MP is sufficient for the intended output, there's no advantage to the APS-C.

Note that I'm comparing in a 'focal length limited' scenario - if you fill the frame with the subject on both cameras, the FF is the clear winner (compare the 7D to 5DIII or 7D to 1D X with the frame filled, i.e. closer with the FF)

More recently, I tested my 1D X vs. 7D with the same motive as yours - use with a 600 II, considering teleconverters as well (and the ability to AF at f/8 vs. f/5.6 on the 7D).  Comparing at the same focal length (bare lens or 1.4xIII), at low ISOs the 7D has a very slight advantage in terms of IQ.  But that advantage is offset by the better AF of the 1D X (shared by the 5DIII).  As you raise the ISO, the 7D is the clear loser - to me, that's a key factor, because at f/4 or f/5.6 with fast subjects, you often need pretty high ISO.  I can shoot the 1D X at ISO 6400, and it looks better than ISO 1600 on the 7D. Again, the caveat is that you have fewer MP in the final image from the FF camera if you're cropping.  But 7-8 MP is enough for decently-sized prints (16x24"), so I'm fine with fewer MP.

When you factor in the 2x vs. 1.4x TC to maintain AF, you need to crop the FF only slightly to achieve the same FoV as the 7D.  In that case, the IQ advantage of the FF is even greater and evident at lower ISOs, and that's despite the bigger optical hit with the 2x vs. the 1.4x TC (note: this is on a MkII supertele - I expect the results would be different on a lesser lens, but the MkII superteles take the 2xIII very well).

Like you, I had the 7D and 5DII combo, the former used for birds/wildlife/sports, the latter for pretty much everything else.  After getting the 1D X, I have come to the conclusion that my 7D is superfluous.  Perhaps worth keeping as a backup camera, but else mainly a paperweight.

Hope that helps...

EOS Bodies - For Stills / Re: ISO 50
« on: January 22, 2013, 09:35:29 AM »
And where  is  my earlier  post?

The one where you made a derogatory remark directed at me?  No doubt it was deleted by a mod.

No it is about words, and what we mean.

HTP is nothing else than while the camera metering for 200iso  the gain is smaller (around 100iso gain) and thereby we get a head room.   ( I describe this as  an under exposure) because the camera  is metering after 200iso)
You get the same effect by under exposing 100iso 1 stop  and later correct the raw file  in the raw converter
In Jpg the camera lay a smoother contrast curve which make a smoother high light reproduction and also lift little bit in lower levels which make the noise little bit more visible.
I hope I have make this message readable so every one can understand

Yes, that's essentially (or maybe exactly) what you've posted previously, and it's clear that you understand the consequences of enabling HTP. 

But it is about words, and many times you used words describing a 'halving of light', 'shorter exposure', and 'the sensor collects less photons' as part of the HTP process, all of which are false.  When that was brought to your attention, you simply restated the same incorrect information.  So while you certainly understand the results of HTP, it's not at all clear that you understand the underlying mechanism, which has nothing to do with altering the amount of light hitting the sensor.  Looking at the responses above, it's evident that I'm not the only one who is aware that you made incorrect statements about the underlying mechanism by which HTP works (i.e., it does not change exposure per se, but only the gain applied).

Regardless, it's clear that you have not acknowledged that you provided wrong information about that mechanism, and I suspect you're unlikely to do so.  That's rather ironic, given that you earlier accused others of being unable to admit their mistakes.  But as I previously stated, I'm not at all surprised by that...

EOS Bodies - For Stills / Re: EOS-1D X Firmware 1.2.1 in the Wild
« on: January 22, 2013, 09:09:58 AM »
EG-S support? :)
Why can't people use Live View? 1Dx has the best AF system in the game, do people really want to compromise that over not wanting to use LV?

If the camera is on a tripod, Live View is definitely preferred.  But usually, when I'm manually focusing it's with a fast prime like the 85mm f/1.2L II.  That combo is pretty heavy - not easy to hold it away from one's body to manually focus in Live View then take a shot, not to mention that such a posture results in increased susceptibility to camera shake.  Manually focusing through the VF allows a 3rd point of contact for better camera support, but it's not optimal for MF since the stock screen doesn't show the true DoF.  Thus, the desire for Eg-S support with proper metering.

EOS Bodies - For Stills / Re: EOS-1D X Firmware 1.2.1 in the Wild
« on: January 22, 2013, 08:21:37 AM »

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