Archive May 2012

Canon versus Tamron VC 24-70mm f2.8 lenses

Posted by on May 31, 2012 in Blog | 10 Comments

Canon 17-55mm f2.8 Lens

Canon versus Tamron VC 24-70mm f2.8

 

Before I went to a full frame camera my favorite lens was the Canon 17-55mm f2.8 IS lens.  I think that this lens is one of the best walk around lenses you can have for an APS DSLR.   I had a 1000d (Rebel XS), then 50D, then 7D.   Between the wide aperture and IS I felt that I could take stunning shots over a wide range of light conditions.

But APS was not good enough for me when you can have full frame.  So I saved my money and got the 5DMkII.  Nice camera.   But now I can’t use my favorite lens anymore.   The equivalent full frame lens is the Canon 24-70mm f2.8.

 

Another great lens but NO IS !!!!   What the heck!  The 5D full frame offers much more data for post processing and and better ISO performance.  If it only had IS…. It would be Great!!.   Yes there is a 24-105 f4 IS.   But many times I want to have a more wide aperture.   I want to have what I had with the 17-55mm f2.8.

Canon 24-70mm f2.8 lens

So when Canon Rumors picked up that there was going to be a new 24-70mm   I was sure it was going to be an IS version….but sadly it was just an improved optics version of the old 24-70.   The old lens was already pretty good.

Then the rumor of a Tamron VC 24-70mm or the full name Tamron SP 24-70mm f/2.8 Di VC USD Lens.   The important part of that was the VC (vibration compensation), Tamron’s version of  IS!  Then the official announcement.  I swore that i would wait till the reviews came in…. but I wanted one so much I went ahead and put in a preorder.

I had not received it yet and some preliminary reviews came in from early buyers.  The onion skin bokeh showed up.

Onion Bokeh take by Kerlu at Canon Digital Photography Forum

OMG what have I ordered!  Then others showed that all lenses do this, in varying degrees,  in similar conditions.   I wonder why I always buy stuff before it is well reviewed.

My main  concern that I still had was that, I know that, when canon makes an L class lens you get good image quality images. But I did not know anything about Tamron.

Tamron 24-70mm f2.8 VC Lens

Anyhow…. it came in the mail.   Oh boy oh boy.

By the way here are the comparative stats ( with prices on 31May12):

Make Canon Tamron
Model 24-70mm 1:2.8 SP 24-70mm F/2.8 Di VC USD
Construction 16 elements 13 groups 17 elements 12 groups
Angle of view 84 dg to 34 deg 84 dg 1m to 34 dg 21 m
Focus Front-Focusing method Front-Focusing method
Closest 1.25 ft 1.25 ft
Zoom Rotating Rotation
Drive USM USD
Stabilization No VC
Blades 8 9 rounded
Min Aperture f22 f22
Lens hood Round some petaling flower shaped
filter 77mm 82mm
Max Dia 3.3″ 3.5″
Length 4.9″ 4.6″
Weight 33.5 oz 29.1 oz
Amazon  price $1,811 $1,299

First impressions about the Tamron VC 24-70mm with comparisons to the Canon:

1.  It feels heavier, but its not .  I always thought the Canon was a big lens for such small focal lengths but the Tamron VC 24-70mm feels wider ( it is at 82 vs 77mm) and it feels denser.  Not sure what that means but I liked the feel of it.

2. The zoom is tight and its on a different ring.  Its closer to the lens in the opposite position from the Canon. I am still getting used to it.  By comparison it makes the canon feel like something is too loose.   One good thing is that you will never experience zoom creep on this.   Tamron included a zoom lock but its overkill and only works at 24mm.   I guess I would like it a little looser but not as loose as the Canon. On the canon if I extend it to 70mm and set it on the table it compresses on its own to nearly 24mm.  The Tamron VC 24-70mm just stays there.

3.  There’s that VC button….. mm-hhmmm,   nothing like that switch on the Canon.  With my old man hands I can take shots down to about 1/80 sec on the canon at 70mm….. not too bad eh.   But with the Tamron VC, on a good day, I can take shots down to about 1/15 sec.  And that my friends opens up a lot more lighting conditions without having to go to high ISO settings.  It is very enabling.

Canon and Tamron Lenses fully Extended

 

Canon and Tamron Lenses Compressed

 

 

 

 

 

 

 

 

Canon and Tamron 24-70 Hoods

4.  The lens is huge,  it is 82mm,  and its right there at the top of the body.   Its like begging for a scratch.   But I looked at the Canon and its just as close.  The hood is fairly shallow too compared to the canon.  The canon hood is huge. I needed the help of a reader to figure this one out.  Tamron’s VC 24-70mm lens hood is what you would expect in a wide lens but on the Canon you need to fully extend it to get to the 24mm.  So the hood has to provide glare protection as the lens moves through it.  The other downside of the 82mm is filters.  I have a Canon 24-70mm 2.8, 70-200mm 2.8, 17-40mm 4, Sigma 50mm 1.4.  They all use 77mm lenses.   So I have 1 polarizer, a 10 stop ND, 1 set cokin filters that all fit 77 mm.   They are useless for this new lens.  So I have already had to get another polarizing filer and I am thinking about getting some of the other filters in 82mm.   So now I have to carry a double set of filters….. ugh.

Note that one reader said that I could use a step down filter adapter.   Also the p series cokin set does have a 82mm glass holder but I have read that you will get some vignetting with that set-up with a wide angle.   So I think I will have to get the pro series cokin filters (more stuff and more $$)  Let me know if this is wrong.

5. General build quality.  It feels pretty good.  the AF and VC buttons are smaller but they are ok

As for performance I don’t see that big of a difference except the image stabilization is wonderful to have…..which is why I got it.   Here are some other things that I found out as I have played with it.

1.   Lens Sharpness is a little better on the Tamron VC 24-70mm at 70mm but a little better on the Canon at 24mm.  I ran Reikan’s Focal lens calibration software on it to see if I could quantify it and sure enough it verified what I thought I was seeing….but these are small differences.

2.  One thing that did surprise me with the FoCal test.   They have a AF consistency test.  You can run 10 or more shots and see how often the target is in focus.  Tamron VC 24-70mm lens was REALLY consistent like within .4 % over 10 points where the Canon came in at around 3.8 %.  Another reviewer found the same result….. So the Tamron has an edge on consistency.

3.  I have had no issues with bokeh.   Here is a quicky comparison of a couple of roughly 100% crops of the first image.   The first crop is the Tamron VC 24-70mm and the second is the Canon.  One reader suggested that I take a picture where there is bright points of light coming through a dark area.   I have included that and you can see the famous “onion skin” effect.   This does not bother me as I do not take many shots like this and its easy to repair with a little blur tool.

 

Tamron Bokeh

Canon Bokeh

 

 

 

 

 

 

 

 

 

 

 

I am not a BOKEH connoisseur but these both look ok to me.

 

4.  There is a small issue with vignetting on the Tamron VC 24-70mm.  You really only see it at 24mm and I don’t normally see it unless I am looking for it.  Here are a couple of shots I took.   Again the Tamron is on the left and the Canon is on the right.  Its there but its hardly noticable.

Minor Vignetting on Tamron at 24mm

Nearly no Vignetting of Canon at 24mm

 

 

 

 

 

 

 

So I would have to say that the Tamron is an equivalent lens to the Canon.  But add the VC image stabilization to it and for me it makes it a much superior lens for my kind of photography.  I did good buying it 😉

 

Reikan’s Focal System- DSLR Autofocus Microadjustment Calibration

Posted by on May 28, 2012 in Blog | 21 Comments

I need and want all of my images to be spot on tack sharp.  So I spend the necessary time to make sure I get that from my photography.

The higher end DSLR’s today come with some kind of lens microadjustment.   And there are lots of ways to calibrate your lenses using that capability.   I wrote about all of the ones that I knew of about a year ago HERE.

But I found a new one…. and its REALLY Cool.  In fact it’s the only method that I use now.  Its Reikan’s FoCal System.

It’s AUTOMATIC or at least that is one of the options.  There is some set-up required but no more than all of the other systems.  After that just sit back and relax while it snaps away.  You even get a data report at the end.

So let me tell you about the System and why I think its so great.   I will also show/tell you about some tips about how to run the calibration.

So what is the system.   Well there is no hardware….its all software.   You need to have a decent printer and a PC or a Mac (in a week or so a Mac version is coming out).  I think its better to have a laptop so that you can set it up close to the camera.  You will need a tripod.   Oh and your camera and lenses are necessary.

How does it work?   Well this is my understanding of how it works.   They have  a target that has a lot of sharp edges on it.   I think they somehow measure the total whiteness of the target.  If the lens is not focused there will be blurring of some of those sharp edges.  That will reduce the total whiteness.   The software controls the camera by taking several shots at each each AF MA (micro-adjustment) point.   A curve of the points of data is plotted of whiteness value (they call it Focus Quality) versus MA point.  They are very secretive on how this all works so this is only a guess on my part.   There is a peak whiteness point to the plot for a specific MA point…. And there is your final MA setting.

The software keeps track of any light changes that have nothing to do with the MA adjustment.   This is important in that if you are using sunlight or indirect sunlight or CLF lighting.   There can potentially be light shifting.   Also if there is not a good curve fit as it traverses the MA spectrum it will ask you to run more data points.  The program can also run focus points off center.  It can run wide and telescoped calibrations on zoom cameras.   It also has a tool that will run a lens through its different aperture values and tell you the sweet ( aperture) spot.

I am an engineer by profession and I gotta tell you that this software is REALLY Cool.

Can I trust it?

I think yes.  I went back to the Lens AlignPro system the I was previously in love with and reran the cal on that and got the same result.  But I realized then that there is a lot of quasi qualitative judgement going on.    In the visual systems you rely on some judgement on where the front focus area starts and where the back focus ends.  These are not hard lines because depth of field focus continuously improves to a focus point and then diminishes to the back end of the the dof.

The Reikan’s Focal System is taking digital measurements (I assume) and using statistics to determine where that peak focus is.  I suppose that a weakness of this compared to the others is that we do not all want our peak focus point in the center of the DOF field.   Some of us want a little front focus others a little back focus.  This is visualized better on a visual system like lens align.  But, you can get the same results by looking at the Reikan’s Focal System data and just picking an AF MA that will put the peak just forward or behind the optimum.  But you won’t get the visual confidence that you CAN see in lens align.

Another issue with Reikan’s Focal System is the lack of a target to camera alignment system.  Reikan’s Focal System does have a neat software system that verifies the target and makes sure that you have enough of the target in the view, that the center is under the cameras center focus sensor, and that the  target is not rotated too far.  But there is nothing that makes sure that the target plane is parallel to the camera sensor plane.  As I discussed in earlier blog LensAlign Pro has a system that ensures these planes are aligned.   I get around that by putting my target on a wall that is more or less perpendicular to the floor.

Another tip is the paper for the target.   Reikan’s Focal System recommends a thick good quality paper.   I ignored this at first and just used regular paper.   Bad idea.  I found that it is difficult to get regular paper to lay flat on a wall no matter how much you tape it down.   In addition I think the higher quality of the paper allows for sharper edges on the target and this,  I believe improves the test.  The paper that I found works best is Office Depot’s Premium Brochure & Flyer Paper.  Its 45 lb paper with a 96 brightness rating.

Its also important to have the target well lit.  I started with just using the indirect light from my windows and the overhead room light.   There were lots errors with added points needed.  Next I tried a couple of small LED lights that I use for reading sheet music.  FoCal instructions say to NOT use LED as it is a pulsing light.  I checked it out on the internet and LED’s do pulse, some as slow as 60 hz.   But they did work out fairly well with an occasional error.   Recently I have been using a large bright (high kelvin) CFL that I use with my lightbox set up.   FoCal also warns about this as it too pulses.   But my research showed that the frequency of these lights are between 1200 and 45000 hz.    All the tests that I have run with FoCal have been with a TCP spring light CLF (6500K), with a pulse frequency of 45K hz, work with this light.  Note that I have found that at 45000 cycles per second that, from internet postings, that the phosphorescence in these CFL’s stay bright between pulsing that is that fast and therefore they are a constant light source.    I think focal would like you to do this in direct sunlight, which I think is impractical,  or will some other non pulsing light.   I am guessing that there are studio lights that do that…. but I don’t have any so my set up will do.

Here is a video of the light discussion:

Positioning the target and camera are important as well.   I measure the height to the center of the target.   I then set up my camera on a tripod.  I have a ball head with a level and make sure that the head is more or less pointing at the target and level.

 

 

 

I then put my camera on the head and adjust the camera height so that the center of the lens is the same as the center of the target.  With that done I look into the viewfinder or the live view and move the tripod/camera left or right to put the center focus sensor on the target.  If the height is not right I will adjust the height again.    Sometimes I have to adjust the ball a tiny bit to make sure that the sensor is right in the middle of the target.  But no major adjustments.  And I deem that good enough.   I am tempted to build a target like the lensalign but with the Reikan’s Focal System target.   Note that I may have totally missed the technology associated with the Reikan’s Focal System and maybe target to camera sensor parellel-ness is not that necessary.

Here is how I do my final alignment of my camera to the target:

 

Finally I run the calibration.   Now there are a lot of presets or preferences that you can set depending on whether you want a very thorough and complete cal or a more cursory one that just gets you in the ballbark.  The camera settings need to be preset.   Although the software will do a lot of this.   The instructions that come with this system are long but very thorough and easy to understand.

When you start the software, with the USB connected it should recognize your camera as one of the cameras that you have registered to this software.  You then need to run the target program to make sure the target is set up correctly.   The software will provide a live view along with visual clues as to where you need to move the camera.  The start the program.   Get a cup of tea or coffee.  Relax.   But do it quickly because the calibration is relatively quick depending on your preferences.   You can also watch the readings as the program goes through the MA selections.

About half way through you will see a colored bar (green) that will indicate an initial guess at the correct MA point.   Then the program checks and validates the MA points near that point.  Then you are done.   The statistically optimum point is chosen and set.   You can even download a report, with lots of pages, detailing the findings for that lens.

There are some other goodies on the software as well.   It will tell you where the aperture sweet spot is on the lens.  It will tell you if you have dust on your sensor and where it is.  It will check to see how repeatable the camera lens combination is on AF.

I think this is just amazing.   Here is video of my running a calibration on a Canon 5D Mk II with a 24-70mm f2.8 lens.

Finally,  I did this cal with the 1.4 version of the software.  It is PC only.   They recently included both the Canon 5 D MK III and the new Nikon DSLR’s.  I know that with the 5D Mk III that it will only run in semi-automatic mode.  So everything is the same but I have to manually change the MA between each shot.   Its not the best but I still will use it over the lens align because I trust the results.   I think that Reikan is working on it.   The Canon software necessary to run the auto was only recently release.   And they are not sure if they will be able to make that camera automatic as of late May12.

The other cool thing is that there will be a MAC version coming out very soon.   Its in beta release now.    I do all my photo processing on the Mac side of my macbookpro so I would rather do the calibration on that side.

A final note.  As cool as ALL of these lens microadjustment systems are,  And again I think Reikan’s Focal System is the best,  this does not guarantee an in focus shot.  Could could be on a tripod looking at a stationary target.  You could have the most rigorous Reikan or LensAlign calibration going for you.   And the shot could still be a little out of focus with AF.   Because AF is not 100% repeatable.  The AF systems today are awfully good but not perfect yet.   So I say do these calibrations and then take lots of shots…. One will be perfect!!

One more thing…. please do not look at the little bits of food on my glasses and lower lip…… Its embarrassing.  I will know now to look in the mirror before my next video.   But its too much work to do these things and I just figured…. what the hell.

How to recover deleted files of my Aperture 3 library

Posted by on May 17, 2012 in Blog | 2 Comments

This post is about how to recover deleted files, in this case Aperture 3 library files.

First….  I am a fairly careful guy with my images.   I use them for personal use and for Microstock (helps pay for all this expensive gear).  I usually download my images to my laptop after a days shooting.  When I get home I process them.  Once a month take all the images on my laptop and move them to a hard drive with ALL of my images.  Every few months I back up that drive to another drive.

None of that helped me with this.

Just came back from a 30 day vacation and the desktop of my Macbook Pro was a mess and full of useless files.  And my hard drive was getting full so I figured I would do some spring cleaning.  15 minutes later my desktop is clean and then I empty the trash.

Now that I have a clean looking desktop I know it would be good to start processing those 400 images  ( took thousands but these were whittled down to the best).  Those images included some of the best I have ever taken like this one:

 

But…. I deleted my Aperture Library!

I opened Aperture and NOTHING was there…. NO Library of images.   OMG….. I trashed the library of images.

I went through the seven stages of bad news:

– Shock or Disbelief – Wait it had to be somewhere else….. Nope
– Denial – This is rediculous…..There is no way I deleted it…..Keep looking
– Anger – GD IT !!!!
– Bargaining —- Not sure I did this one
– Guilt –  I don’t deserve to be a Photographer
– Depression – This is so sad I can’t stand it
– Acceptance and Hope –    Wait maybe there is a way.

How I recover deleted files

So I did a bunch in internet research.  Now this is mostly MAC based but some of these programs have PC counterparts.   I checked out Disk Warrior, Data Rescue IIIDisk Drill,  and a few others.  I looked for reviews and they were all over the place.   Most of this software will allow  a free download that will discover the trashed files but then you have to pay to RECOVER the files.   I found Disk Drill to be one of the betters.   I found that they all found the same files.  And the recoveries were similar.  I picked Disk Drill because  it allow for some filtering of the results like, when deleted, file size,  chance of recover, type of file.  Make sure that you have an external drive connected or another partition.   You will want to cease and desist from any downloading to your main boot drive.   This is because every time you add more data, like a download,   you could be writing over one of those precious images.

 

So I ran the programs.   I recovered about 900 image files!!!  That was the good news.   The bad news is that about 50% of the files were corrupted with only part of the images showing.   The other issue is that many of files were images that I had rejected over the past year for lack of image quality.  So it took HOURS to go through all of the images and sort out the the images.

In the end I got about 300 of the 400 images back.  Most of my best ones were recovered.

Then I had another brilliant idea….. could many of the images still be on my CF data cards.   The problem there is that I erase and reformat them after every use.   I ran disk drill on them as well  and found a lot of earlier shots that were part of my laptop  yet-to-be-loaded microstock images.

Moral of the Story

1.  Don’t keep you library or folder of images on your desktop where it is easy to drag to the trash

2.  Do not go into depression…. you probably can recover many of those images.