robin_sibson1

<p>On a 1.6-crop-factor body the broken zoom and the lenses you are considering as a replacement are standard zooms not WA zooms. Go for an EF-S lens to get maximum VfM, and certainly do not waste money on L-series lenses optimized for FF. Look at the EF-S 18~55STM, 15~85, and 17~55/2.8 depending on how much you want to spend.</p>

<p>AS plates mounted by a single ¼" screw come loose and slew far too easily unless either they are shaped to the foot, or they have a video pin (which the Canon foot accepts), but in any case it is a clumsier solution than getting a foot that does the job.</p>

<p>http://www.lensrentals.com/blog/2015/02/canon-100-400-is-l-mk-ii-teardown-best-built-lens-ever</p> <p>Impressive piece of engineering. This saves ne the trouble of taking mine to bits :-)</p> <p>I still think it is a pity that the tripod ring is not removable for more convenient hand-held use, and that a replacement foot (from Kirk or RRS) is needed for Arca-Swiss mounting.</p>

<blockquote> <p>I think DPP should support every Canon camera that can shoot RAW, regardless of the camera's age. I know some people will always argue "nobody shoots with a 10D anymore, why does it need to be supported?". But to my thinking the question isn't "does anybody shoot with this camera anymore?" but rather "were there ever any important photos taken with this camera?". Some photographers do have important photos in their archives shot with a 10D, even if they haven't used that camera in ten years, and they will always need software that can read those files.</p> </blockquote> <p>That is exactly the point. Canon have been ruthless about withdrawing support for camera to computer connection of older bodies, even 1D series, but orphaning images taken a few years ago is a wholly different matter, and would be completely unacceptable.</p>

<p>There has always been some pretty neat stuff in each generation of XXXD/Rebel/Kiss cameras, but the continued used of a low-magnification pentamirror finder separates them firmly from the higher-end bodies.</p>

<p>In successive versions of DPP4, Canon have already started to do some back-filling by supporting bodies that are no longer current. Let us hope that they understand the need to do that over time for all CR2 files, even those from non-EOS bodies. Meanwhile, DPP3 is still available and being updated. Running two versions during a transitional period (if that is what it turns out to be) is not a big deal, especially if it reduces the risks associated with jumping to a completely new version.</p>

<p>Jim L, I agree with other posters that you should at least investigate having the 24~105 fixed. But here's some information for you.</p> <p>I use a dual-format kit with my main general-purpose camera being a 5DIII. Sometimes I want to be able to use my 7D on its own, but not often enough to buy an ideal combination of lenses for that purpose. So at the cost of a less-than-ideal changeover point, I use the 10~22 and 24~105 as a carry-round kit, and that works pretty well.</p> <p>Twelve months ago I added a 24~70/4 to my kit, for FF use when I am carrying a 70~200 (so am not bothered about the 70~105 range – the 70~200/4IS is better over that range than the 24~105 anyhow) and when I may want to take a few close-ups but not enough to carry my 100/2.8L as well, The 24~70/4 is a very neat lens and is optically as good as or (mostly) somewhat better than the 24~105 throughout its more limited range. It has a genuine close-up capability, but is not ideal for use at the extreme end of its close-up range because working distance is small enough to cause real lighting problems. Also, it has some focus shift at 70mm at the MFD end of its normal focus range. But it does what I bought it for, and I usually carry it in preference to the 24~105 with my FF kit. That said, I do really see it as a FF lens and would not be particularly keen on it for crop-factor use.</p>

<blockquote> <p>For those people who think the <a id="itxthook5" href="/canon-eos-digital-camera-forum/00czwo" rel="nofollow">image quality<img id="itxthook5icon" src="http://images.intellitxt.com/ast/adTypes/icon1.png" alt="" /></a>/high ISO performance of the 50D is worse than the 40D I urge you to resize the 50D files to match those on the 40D and then compare. I see no benefit to owning a 40D over a 50D except for a few extra coins left rolling around your pocket.</p> </blockquote> <p>I agree. I had each of these two bodies when they were introduced, the first replacing a 20D (never thought it worth bothering with the 30D) and the second being replaced with a 7D. The 40D introduced Live View but did not have contrast detect AF, which was, frustratingly, introduced only a few months later in an XXXD/Rebel body, and the sensor was scarcely any step forward from the 20D/30D sensor. The 50D was quite a big step up from the 40D but was quite noisy on a per-pixel basis at high ISO. But do not waste your time with it. The bargain to go for now is a s/h or close-out 7D, a big step up from the 50D with far better AF and, despite the slight increase in pixel count, very much better noise performance. Of course, that's assuming that the 7D Mark II is not within reach.</p>

<p>Not possible unless an extension tube is used as a spacer, which will probably lose infinity focus. The only Canon Extender that allows another Canon Extender to be stacked behind it is the 2× II, and you can stack any Canon Extender behind that – you have already checked this with the 1.4×. You are pushing the limits of optical quality with your present setup.</p>

<p>The rear barrel section of the 70~200/4L IS is plastic. I have never heard any reports of it failing in normal use, and my own copy has been fine, but IIRC I once saw a report that in a severe impact from a fall the plastic section broke cleanly leaving the lens repairable, an unlikely outcome had that section been metal. Personally I have no problem with appropriately used engineering plastic; some folks are upset by it.</p>

<p>My son has a 300/4L IS which I have used from time to time, most recently when he lent it to me for a wildlife trip to Costa Rica last Feb/Mar. On its own it is a pretty good lens, although it shows its age a bit, for example with the IS. It works acceptably with the Extender 1.4× (original, II) although AF is slowed. Performance with the Extender 2× II on a 5D Mark III is a bit marginal. AF technically works (slowly) at f/8 on that body at centre, fine centre, and centre+4 AF points, but focus racks through the range at the slightest provocation, and it is necessary to switch focus racking off to make it useable. IQ is not great with that combination, at best marginally preferable to using the 1.4× and cropping. It is important to carry out careful AF microadjustment for the lens+Extender combinations at the likely working distance. </p>

<blockquote> <p>(no, it's not that I'm failing to flip the switch to enable the dial</p> </blockquote> <p>Peter, I think Sean is on top of this issue.</p> <p>Sounds to me like an intermittent contact in the dial itself or the dial enabling switch. My guess is that a repairer could fix it quite easily, although I appreciate that it may not be worth spending the money. The saving grace is that the original EOS-1 (and the EOS-1N) was designed to have full functionality without the use of the QCD, because there was an alternative back that imprinted data on the film but did not have a QCD. The EOS-1V changed from sprocket to optical film advance control and did not accept the earlier backs, but the workround to avoid the need to use the QCD was retained but not documented.</p>

<blockquote> <p>Scan from the Canon F1 brochure published in November 1970:<br> <a href="/photo/17905233&size=md" rel="nofollow">http://www.photo.net/photo/17905233&size=md</a><br> From left to right: FD35mm f/2, Fish Eye 7.5mm f/5.6, FD28mm f/3.5, FD135mm f/3.5, FD35mm f/3.5, FD135mm f/2.5, FD50mm f/1.4 (mounted on F1), FD17mm f/4, FD55mm f/1.2, FD100mm f/2.8 and FD50mm f/1.8.<br> Chrome nose lenses not shown include the FD24mm f/2.8, FD55mm f/1.2 AL, FD85mm f/1.8, FD200mm f/4, FD300mm f/5.6 and FD100-200mmm f/5.6. The initial group of lenses listed in November 1970 included the TS35mm f/2.8 AL. However, the actual lens marketed did not have an aspherical element nor did it have a chrome nose.</p> </blockquote> <p>I am looking at this image in my copy of the F-1 brochure (Pub. No. 5367A) which I have had since buying my F-1 in 1972 along with 24/2.8, 50/1.4 and 100/2.8 chrome-nose lenses. The upper part of the image shows the front end of the 200/4 and 300/5.6 with a black (not chrome) knurled ring for gripping the built-in hood, whereas the 135/2 is illustrated with a chrome ring, as can be seen in GY's scan.</p>

<p>David, no, I am saying that cropping the digital image but keeping the print size constant changes DoF. Please do not put words in my mouth. Everyone is entitled to their own opinions, but not to their own facts. I am disappointed that you do not understand the elementary geometrical optics involved, but there seems to be nothing more that I can do about it.</p>

<p>David, I am sorry you do not understand this basic point. Let me make one more attempt. DoF is defined in terms of a "circle of confusion" based on how much out-of-focus blur you are prepared to tolerate in your final image, say, a 36cm×24cm print (or equally a 36cm×24cm display on your screen). That circle of confusion on the print corresponds to a circle of confusion on the sensor; if the sensor is 36mm×24mm it is one-tenth of the size, and if the sensor is 18mm×12mm (whether by design or cropping) it is one-twentieth of the size and thus the DoF is different in the two cases. It would be the same only if your print size was also reduced with the print viewing distance kept constant.</p>