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Old Dec 21, 2008, 9:36 AM   #1
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Hello mtngal!

I did the Gear Shoot Out yesterday. My buddies were over at my house yesterday so I set up my flash stand & shoot through umbrella and fired off some test shots with everyone's set-up.

Image Quality
------------------
In short, I am still amazed at the detail I am getting with my Pentax K100D. I'm just barely happy with my Nikon D70s (but with it's built-in light for focus-assist, it is turning into my point-and-shoot dSLR.) And as for the Canons (XT, XTi & XSi), they all gave great images, but I think I was most impressed with the XTi. It has noticeably more detail than the XT. As for the XSi, I guess I was expecting more from it's 12 mega-pixel sensor. I'm just thinking, I got to get my hands on a Pentax K200D to see how it would do in this test!

The images, they can be viewed on my Flickr Stream here . . .

http://www.flickr.com/photos/tacticdesigns/

Medium to Low-light Auto Focus Performance
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One of the other test I conducted was auto focus performance in medium to low-light. Just had one light on in my bedroom and no light on in our bathroom. Took each camera (with none of the cameras having any external flash hookedup) and while standing in my bedroom aimed them into the bathroom and saw how long each camera took to acquire focus and take the shot. My Pentax K100D seemed the slowest, with the Canons just noticeably better. The Nikon did the best with this test because of the built-in light that lights up the subject and helps the camera focus.

My buddy with the Canon XT watched me while I was doing the test because he was getting annoyed with the low-light focus problem with his XT. When he mentioned he was thinking about getting an external flash, I thought ok lets play with the gear. So . . . I grabbed my other buddies Canon 430EX ext. flash and hooked it up to his Canon XT and told him to try to get the camera to focus in really low light. The camera acquired focus in a split second. He looked at me and said, "well, that problem's solved. why?" So I told him about the IR focus beam in the flash. I then showed him how the 430EX with TTL really makes shooting with flash a "no need to think" proposition and bounced the flash around. Each image coming out nicely exposed.

As a further test I grabbed my buddies XTi with the Sigma 18-200 3.5-6.3 and zoomed out to 200mm (so the lens was at f6.3), we tossed on the 430EX and tried to focus in low light (shooting down an unlit hallway) and the camera acquired focus ASAP and fired. Problem with >f5.6 solved.

Later in the night, he was playing with the 430EX on his camera, snapping pictures of his kids, bouncing the flash off the ceiling with a big smile on his face. I'm pretty sure he's buying a 430EXII & Gary Fong Lightsphere II (frosted) in the new year. (Yeah. More gear to play with!) He was also looking at getting a super zoom. I told him price out the Sigma 18-200, Tamron 18-200, Tamron 18-250 or Tamron 18-270 [He's got a Canon so he can get that lens]. Get what he wants to pay & he'll be happy with any of them.

As for the XSi with it's live-view focus. I couldn't get the camera to focus at all. Even with amply light to focus by. My buddy says that he thinks its because he has a non-Canon lens. (Sigma 28-300). I didn't feel like playing around with that yesterday.

Metrix Metering with built-in flash
------------------------------------------
I did a little testing with metering with the built-in flash. I think the king is the Nikon D70s. The trick with the D70s is that you have to put it into auto-iso and then in a wide range of med to low light situations it just sorts everything out and takes a nice pictures. The trick with the Pentax K100D is that you have to put it on auto-iso + you have to have the camera in GREEN mode. It seems that the auto-iso only works on the GREEN mode on my Pentax K100D? The Canons I didn't do as much testing. (I didn't want to change all the settings on the cameras and not remember how to switch it back.)

Lenses
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As for the lenses (Canon 18-55, Sigma 18-200 Pentax mount, Sigma 18-200 Canon mount, Promaster 18-200 Nikon mount, Sigma 28-300 Canon mount), to me, they are all about the same calibre. They are not expensive lenses. They're cheap! But completely useful! The difference in image quality with my shots had more to do with the cameras than the lens.

My Conclusions
-------------------
I guess my conclusion is that . . . 1) I am still happiest with the image quality I am getting with the Pentax K100D. Not so happy about the med to low-light focus (but this can be tamed with a <f5.6 lens or external flash) and I'm not so sure if the Nikon D70s is a better point-and-shoot camera with its matrix metering. (still want to play around with it more.) Although I like the Canons and I think the 430EX flash unit is one of the best priced flashes, with a wide range of features & super easy interface to get to all the features, although I would seriously tell some to look at that platform if they don't have gear yet, I wouldn't jump ship to that platform from my Pentax platform.

Future Test
--------------
1) Try out a Pentax 540FGZ on my Pentax K100D to test out med to low-light autofocus performance & TTL performance.
2) Try out the Pentax K200D to make sure that image quality is still amazing! (And slate that as my, when I got time and patience to take the shot, use this camera!)
3) Try out the Nikon D80 or D90 to see if I am happier with image quality than my D70s. (If they've improved it, which I'm sure is the case, then I might look at getting a used D80 down the road as my point-and-shoot dSLR, which is how I am using my D70s.)
4) Learn more about the Metz 54 mz 4i external flash unit to see if I can get it to work on both my Pentax & Nikon with the feature set I want.

Take care,
Glen



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Old Dec 21, 2008, 10:12 AM   #2
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Very nice pictures! Interesting how the Canon's AF low light focusing without the flash - I would have thought it would be better (since Canon is supposed to have such a better AF system). Also interesting about the extra detail with the K100 vs. the D70 - I think the two cameras share the same sensor so the differences would be how the camera manufacturers chose to process the image. It would be interesting to take the pictures in raw and then open them in the same raw converter also.

The one thing I noticed with the pictures, the differences are small.
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Old Dec 21, 2008, 12:02 PM   #3
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Hello mtngal,

RE: low light auto focus test -- I created this test situation (ie. one light) because it is just a bit worse than a lot of the shooting I do. (ie. Bad lighting at a friends house while we get together. It's not that unlike shooting a child's Christmas assembly in a poorly lit gym. <grin>)

In situations like this, I think the degradation in auto focus performance probably has more to do with f-stop (ie. you run into trouble > f5.6) than how each manufacturer has their autofocus system designed. [Meaning, everyone has a fairly good autofocus system.] From my not-so-scientific-tests, the quickest way out of this problem with any system is be at less than f5.6 (the bigger the aperture the better) or get some focus assist lighting. (On my Nikon it is built-in, but most good flash units have the even better IR focus assist.) Problem solved!

Side note: Since figuring this out, I've gone back and now I notice that most of the Nikon and Canon lenses offered only go to 5.6. They don't go past that. For instance, the Canon 18-200 lens is f3.5-5.6. (Same as the Nikon.) That's why some people might think that Canon (with a Canon lens) might have a faster focus system. But me and my buddies all bought the cheaper Sigma or Tamron lenses. And . . . if you put the money you saved towards a good flash unit, I think you come out ahead with the capabilities of the external flash!

As for the Nikon D70s & Pentax K100D having the same sensor, I knew they were both Sony sensors when I picked up the Nikon D70s. I wasn't expecting such a difference in rendering. It really caught me off guard. When I picked up the Nikon D70s, I was figuring that with its built-in focus assist light, cheap high-speed sync capability, built-in commander flash, quick access button layout, etc. that I would abandon Pentax. Instead, I just really came to appreciate my Pentax K100D that much more. I just can't walk away from this camera.

That is why I want to get my hands on a Pentax K200D to make sure Pentax hasn't changed how it works with the CCD sensor. I think they really did a good job on that! I just want to see what it can do!

[NOTE: To really notice the difference in these images, you have to download the big version of the images, open them up in Photoshop and zoom into the eyes. I've noticed that the biggest difference between the camera bodies is how the eyes get captured and rendered. Other than that, there is little difference. But . . . to me, the eyes are really important, because that is the first thing in a portrait that you are drawn to.]

As for shooting RAW. I shot RAW on the Pentax and Nikon and then opened the RAW files in Photoshop the same way. I don't have the Nikon Capture software to see if it renders the Nikon RAW better than Photoshop, so I don't know if the odd pixelation I am seeing in the Nikon images is being caused by Photoshop. [But . . . when I shot in JPG on the Pentax and Nikon, I notice the same odd pixelation on the Nikon generated JPG files.]

Now that I've done this test, which I've been meaning to do for about a month now, I think I'm done comparing platforms.

End result.

Does platform matter?

Yes & No.

As you often read in magazines. Each platform has its strengths and weaknesses. The strengths may be in how the camera treats the particular subject that you shoot often, or easy access to more manual controls, or it could be the price / performance ratio of what is available in that platform. (I think Canon's 430EX/II has a great price / performance ratio! I also think Pentax's 10-17 fisheye has a really nice price / performance ratio! <grin> Can you tell this is on my want list as well!)

A friend's daughter asked me what camera to get. I told her some strengths and weaknesses. But then I just handed her my Pentax & Nikon and my buddy's Canon and told her try them out. [Then I told her, if she gets a Canon XS, then she could use her mother's big zoom & flash unit without incurring additional cost. <grin>]

Take care,
Glen



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Old Dec 21, 2008, 12:49 PM   #4
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You've had me head scratching there Glen ... I was searching the manual for "Green Mode" ... Thought I'd missed something for a while, I'm guessing you mean Auto Pic

mode, that's the way it's labelled on my K100D, you sure had me chasing rainbows. LOL :lol:... Jack
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Old Dec 21, 2008, 12:59 PM   #5
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Sorry jachol!

Using Nikon, Canon & Pentax, I just keep getting what each platform calls the same feature mixed up, so I just come up with my own terminology for the feature. <grin>

Take care,
Glen


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Old Dec 22, 2008, 3:33 AM   #6
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No Problem Glen !, in the end it was a giggle when the penny dropped. :-)
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Old Dec 22, 2008, 7:43 AM   #7
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mtngal wrote:
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Very nice pictures! Interesting how the Canon's AF low light focusing without the flash - I would have thought it would be better (since Canon is supposed to have such a better AF system).
A few notes on Autofucos performance.
  • As Glenn pointed out - most cameras suffer in low light focusing with slow lenses. Typically you want at least f2.8, preferably f2.0 lenses.[/*]
  • focusing methods vary by camera even within manufacturer. For instance in Canon, the ancient 10d focused well in low light - for a couple generations after that the low light focusing was actually WORSE. In the tests I've seen I think Sony's A700 is actually one of the best low light focusing cameras[/*]
  • Besides aperture, you have to remember Canon & Nikon focus systems are a combination of body and lens. The lens has the motor in it. In canon's system there are actually 3 different focus motors - 1. non-specified (i.e. poor) 2. Micro USM 3. Ring USM. So, you get better focus performance as you climb the lens food chain. To my knowledge I don't think Nikon has different categories - just AF-S or non AF-S (non AF-S means it relies on the camera's focus motor). All very confusing. Canon focus motors are always in the lens, Nikon's can be in either - the faster ones are in the lens. Sony is similar to Nikon. They have focus motors in the cameras but their newer performance lenses have built in focus motors. In third party lenses, only Sigma's HSM focus drive is really on par with the AF-S and ring USM lenses for Canon / Nikon. If you want to see the real focus performance boost, use Nikon or Canon's better lenses like th 70-200 2.8 AF-S and 70-200 2.8 L .[/*]
  • Again as Glenn pointed out, focus assist beams are a huge benefit to ANY camera in low light. Although an interesting point - at least in Canon - if you have focus tracking on, the assist beam doesn't work. I'm guessing that's because it's a continuous focus type of thing. I discovered that the hard way :G[/*]
  • Also, as to your comment about the focus systems being better in Canon - the real area where Canon and Nikon excel is in focus tracking. The lens-based focus motors become more advantageous because you have a LOT of little adjustments. you don't notice it as much on single shot but you do on continuous. Beyond that though are the focusing algorithms for what's called "predictive focus". In continuous focus the camera isn't just re-focusing every split second it actually calculates the vector of the subject and predicts where the subject will be. Having more sports and wildlife shooters as customers this is a critical success factor for Canon & Nikon. The other manufacturers not so much. So it's not worth the R&D to get up to the level of Canon & Nikon. Sony's A700 is very good though (although not so much the cameras below it).[/*]
  • Another aspect of the focus systems is the technology of the focus points involved. Which points in a given camera are "cross-type" ? I.E. can detect differences along both axis instead of just one. And which and how many focus points are "high precision" - i.e. have increased accuracy with wide aperture lenses (sometimes f4, more often 2.8).[/*]
  • Final aspect of focus systems is the number and placement of focus points. Nikon's prosumer and pro cameras have 51 points. Canon's pro cameras have 45. Now, people are tempted to say - I don't need that many points. But, what it allows is flexibility. In Nikon for instance you can select several different values for how many points to use in focus tracking. In Canon's you can select to enable or disable 'assist points' (only 19 of the 45 points are actually selectable for use the rest are assist points). For still work, being able to select 1 of 19 points with a joystick allows me the ability to not have to focus/recompose and still get the composition I want. Also, on the camera I use I have 19 high-precision , cross-type focus sensors. So when I'm shooting sports I can select a non-center point for better in-camera framing and still get the best possible focus performance out of the camera.
[/*]
All in all, auto-focus is a lot more complicated than people think - lots of variables. The key, as with anything else in photography is to understand your specific needs and find a solution that best fits your needs.

This is not to say Glen's test wasn't a great idea - it was, and very well executed. It's just to say at least with AF, it's a little more complicated than the test Glen performed.

Great job Glen and thanks for sharing your test results.
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Old Dec 22, 2008, 9:09 AM   #8
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Hey JohnG,

Yeah. My tests were specifically designed for where I was having the most trouble (friends and family shots in not so great lighting) & geared towards the subject matter that I am concentrating on right now (portraits of my daughters).

For me personally, if I get that resolved, that is 90% of my shooting.

As for when friends ask me what type of camera to get, I ask them what they are going to shoot, tell them some of the pros and cons of each platform I'm aware of and tell them to try out as many cameras as they can.

A camera choice really is dependent on what you want to use the camera for and how you want to use it.

Take care,
Glen


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Old Dec 22, 2008, 9:13 AM   #9
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tacticdesigns wrote:
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Hey JohnG,

Yeah. My tests were specifically designed for where I was having the most trouble (friends and family shots in not so great lighting) & geared towards the subject matter that I am concentrating on right now (portraits of my daughters).
You seem to like flash so focus assist is the way to go. But fast primes can help a lot too. Some flash/cameras will allow you to use the assist without firing the flash. Otherwise if you want the assist without the flash you can put elecric tape over the flash head so it's firing doesn't affect the shot. If you do that alot you could get an omnibounce and put the tape on that so you can add/remove the "flash cover" at will.
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Old Dec 22, 2008, 9:29 AM   #10
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Yeah. A good flash is the very next thing on my list.

Even before upgrading from 6 mega-pixels or getting some fast primes or getting the Pentax 10-17 fisheye. <grin>

[For what & how I'm shooting now, I think I'll get a really big bang for the buck by getting the good flash unit before anything else. Once I get the good flash unit, I can start looking again at upgrading the camera and lenses down the road. <grin>]

[Actually, that is whyI did this test series. For what and how I shoot, do I stick with Pentax, side step over to my Nikon or go with Canon. Once I made my mind up where I was going with the platform, then I'd know what flash unit to get. I've been looking at the Metz 54 mz 4i because it is supposed to be able to be used on both the Nikon and Pentax, but reading through the manual, I am more confused than before. I don't know how much I'd be giving up by not going OEM. And having played with a Nikon SB800, I don't know if I'd be comfortable with its menu system. At this point in time, I'm really swaying towards getting the Pentax 540FGZ. But whatever I get, I'll know that I've done a bunch of testing to make sure that, for me, it was the best compromise.]

As for using the focus-assist of the external flash, without using it as a flash source, I'm completely looking forward to that as well!

I'm going to try the electrical tape over the built-in flash! Thanks for the info!

Take care,
Glen



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