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01-19-2010, 01:58 AM   #31
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Image quality wise I guess they are fairly equal, although it seems the Kx has more aggressive (and thus visible) nosie reduction at high ISO.

The D90 has pentaprism viewfinder, much better LCD screen, better AF, double thumb wheels (very important to me at least) and more direct control buttons. It is a clear winner (in my opinion).

01-19-2010, 02:24 AM   #32
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QuoteOriginally posted by Boris Quote
Consider this. You walk down your favorite street/forest/museum/etc and see the scene that you'd like to capture. You bring your camera to your eye and do whatever you think has to be done: focusing, exposure, actually composing the image. You click the button. Light goes all the way through all the glass pieces of your lens and strikes the sensor. The file is written on to the memory card. Later on you download it to your computer and spend your time tweaking, processing, editing, modifying the photograph until you're satisfied with what you see.

It seems to me that camera although important is not the most significant part of this process. It is just one of many components, so to say.

I humbly suggest that you consider what I wrote and think about it a little.

Given that both K-7 and D90 are modern DSLR of medium to high class, I suppose that they both will give you great many wonderful photographs. But you'll have to solve the above equation on your own the way you like it. Noone can really do it, but yourself.

I am sorry if you expected a technical answer, 'cause it is extremely difficult or almost impossible to provide one that would be objectice and unbiased.

Well said, Boris. I concur with you!
01-19-2010, 02:58 AM   #33
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It may seem like going against the tide - but perhaps you'd like to look at this thread:

Kx in Use

where I have been using the K-x in pretty challenging lighting conditions -

ISO5000, f/4, 1/30 would be about my average -
that's about 2 foot-candles = 22 lux = 22 lumens/sq metre

I only use the kit zoom lenses 18-55 and 50-200.

There are some who seem to poo-pooh the kit zooms, but the Pentax kit zooms are actually of very good quality as reviews (and hopefully my results) show.

Popular Photography tested both the original 18-55 (as the Samsung clone) and the more current 18-55 AL II versions -
this is the very useful SQF (Subjective Quality Factor) chart - from their review of the Pentax DA 18-55 AL II -


They also tested the 50-200 as the Samsung clone -


Both these lenses are of very good quality -
certainly nothing to be sneezed at.

The newer Pentax 55-300 zoom also seems to have tested well

The point I have tried to make is that with the better performance at higher ISO on the K-x - one can now use lenses with more modest maximum apertures because one can now use higher ISOs - hopefully that can be seen in my photo samples posted in the thread Kx in Use (for the "short version" look at Post #8)

Hope that gives you another perspective.
01-19-2010, 05:32 AM   #34
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ISO vs F-stop playoff....

QuoteOriginally posted by UnknownVT Quote
It may seem like going against the tide - but perhaps you'd like to look at this thread:

Kx in Use
...
The point I have tried to make is that with the better performance at higher ISO on the K-x - one can now use lenses with more modest maximum apertures because one can now use higher ISOs - hopefully that can be seen in my photo samples posted in the thread .....
There's an important playoff between ISO, f-stop, and display format underlying all the above comments.

As display size goes down, ISO and/or f-stop can go up for an acceptable quality display. It appears that the K-X camera's high ISO performance is something like twice as good as earlier similar cameras.

This implies you only need half as much light to make an equal quality display; hence, you can hand-hold the camera adequately with a one stop slower lens.

The examples Vincent shows in his link look superb to me. Based on those examples, the k-x and kit lenses will be sufficient for really good looking, out-of-the-camera, non-enlarged or shrunken, computer displayed photos.

My experience is that for low light shots with a K100D I can get away with an f:1.7 - f:2.0 lens.... Some say f:2.8 is sufficient for a school gym - that implies the kit lenses might be ok for the K-x (but I wouldn't bet a lot at the long ends of the zooms.)

Dave


PS lenses faster than f:1.7 or so are difficult to use because the portion of the subject in focus is very small.

01-19-2010, 11:37 AM   #35
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QuoteOriginally posted by newarts Quote
There's an important playoff between ISO, f-stop, and display format underlying all the above comments.

As display size goes down, ISO and/or f-stop can go up for an acceptable quality display. It appears that the K-X camera's high ISO performance is something like twice as good as earlier similar cameras.
Thanks for that nicely put input,
as well as your kind comments.

Yes, with the K-x high ISO performance I can "get away" with the humble kit lenses (which actually are of very good optical quality).

Also remember to take into account the effective SR of Pentax dSLRs - so with relatively stationary subjects one can also allow for slower shutter speeds.

I am currently still on Firmware version 1.01.05 (ie: the interim version before the rumored silent upgrade 1.01.07 - that's speculated of addressing some SR issues - note my caveats in italics). I have found for my shooting and conditions I can gain between 2.5 to 3.5 stops(!) depending on whether I support my arms or not (respectively) -
I know dpReview seemed to have found only about a marginal 1 stop gain -
but these are my own ad-hoc tests - and as always YMMV.

So for me the K-x really does allow me to shoot at much lower light levels with the kit lenses that most people would probably laugh at (me)

But as one can see from my sample photos eg: in Post #8 of Kx in Use - I get quite acceptable shots at as low as 1/4 sec quite consistently -
of course subject motion may become a problem - but then again sometimes it's the motion that makes the picture:

K-x - ISO3200, 1/13, f/4, 18-55 kit Zoom
01-20-2010, 02:52 AM   #36
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QuoteOriginally posted by pakuchn Quote
I don't have any lenses, I'm starting new. I have $1600 to get new equipment, and if I have to go over a little it's not a problem.
Thats good, don't get a K-x while you can afford K-7, here is my solution and I am very happy with it. First three lens with a K-7 will make you fly from happiness. This setup is even below from your budget, don't forget to get an extra battery too, or an AA battery grip. Then you are a top Pentaxian, in the gear sense of course..

https://www.pentaxforums.com/forums/881938-post11.html

Last edited by cbaytan; 01-20-2010 at 03:05 AM. Reason: add info
01-23-2010, 11:31 AM   #37
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Just wondering, which flash do you all own?

I was looking at the Pentax 540 and metz 48 and 58.

Thanks.
01-23-2010, 11:40 AM   #38
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QuoteOriginally posted by pakuchn Quote
Just wondering, which flash do you all own?

I was looking at the Pentax 540 and metz 48 and 58.

Thanks.
I have the 540 because I wanted to have 1 PTTL flash where I can shut off the auto-shutdown. Its my master flash when I shoot strobist.

01-23-2010, 02:04 PM   #39
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QuoteOriginally posted by pakuchn Quote
Just wondering, which flash do you all own?

I was looking at the Pentax 540 and metz 48 and 58.

Thanks.
Metz 48. Worked pretty well until my daughter pulled down cam&flash combo and broke the flash's foot. To me, the biggest con of the Metz is that it can't do full swivel 180 degrees on both sides (it can do about 135 deg on the right side).
01-23-2010, 05:11 PM   #40
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QuoteOriginally posted by Rondec Quote
I would get the Kx with the lens combo of the 55-300 and 18-55. If you decide you want to upgrade, you can always sell the 18-55, but it is an awfully light lens and if you buy those two lenses on their own, you will pay 300 dollars easily. I think I would really wait to buy anything "upscale" until you are familiar with the camera. As mentioned above, there are a lot of lenses out there that are "better" than the kit lens, but I would still start with that.

This is in my opinion the best advice in this topic, especially if this will be your first DSLR camera. The kit lens is the best value for money. If you really want to jump right in the deep you could buy an FA 50mm 1.4 as well, or a DA 40mm 2.8 if you like your camera to be as small and fast focusing as possible.
I wouldn't buy an external flash unit yet, 99% of the time it is not needed.


To answer your flash question, I own a metz 48, it is a really nice flash for the price but I use it much less than anticipated.
01-23-2010, 06:43 PM   #41
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A lot of good advice here and maybe someone mentioned this and I missed it, but if you are planning to take lots of photos of your child and take family vacation photos, you may not want to mess with multiple lenses. Your family will likely not want to wait around for you to change lenses between shots. I've never used the D90 (or anything other than a Pentax), but like others have said, you can get great photos with either. The K-x appears to be the high ISO king (I have one, but I don't take a lot of high ISO shots) and is smaller than the D90. I have looked at other Nikons and found the ergonomics to be inferior to the Pentax designs. So my advice is to start with the K-x and the 18-55mm kit (it's an excellent lens as others have noted). Let the extra money simmer in your pocket until you feel you are ready to expand your collection. I've found the Pentax/Tamron 18-250mm lens to be the only lens I need for the multiple trips I have taken to Europe, but on my next trip I'll also have my new 12-24mm lens which cost more than the camera!
01-23-2010, 06:55 PM   #42
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Thank you for the great info.
I do want to get one lens for indoor, such as family events and other events such as indoor autoshows and motorcycle shows.

I been looking at also getting a processing software. I know Nikon uses something called Capture NX, but I dont think Pentax has anything similar.
01-23-2010, 07:34 PM   #43
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Your Pentax will come with Pentax Digital Camera Utility 4 that is based on SilkyPix. A lot of people love it and say that it provides the best color rendition of photos from a Pentax DSLR, some find it not very user friendly. There are lots of postings about RAW processors here. I use Adobe Lightroom and love it.
01-23-2010, 07:36 PM   #44
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Thanks Rob.
01-23-2010, 09:25 PM   #45
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Is your computer a Windows PC or a Mac? I have a Mac and use Aperture with two plug-ins: Noise Ninja (for noise reduction) and LensFix (for correcting lens distortion - although the K-x features some of this in camera if you use Pentax DA lenses). By the way... I officially vote for your buying the K-x. The D90 is a great camera but the K-x is a better value, smaller and lighter, and has superior ISO performance when shooting jpgs.
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