Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
10-23-2009, 05:10 PM   #1
Veteran Member

Join Date: Sep 2009
Location: Texas
Photos: Gallery
Posts: 3,499
Resolved. Problem was me, not K7


Last edited by r0ckstarr; 11-11-2011 at 11:06 AM.
10-23-2009, 07:00 PM   #2
Veteran Member
Pentaxor's Avatar

Join Date: May 2009
Location: Vancouver, B.C.
Photos: Gallery
Posts: 6,513
why is it that if someone can't get a good picture, they always blame the camera for it?

btw, since you can't get past 1/250 during daylight, you are definitely doing something wrong with the camera.
10-23-2009, 07:14 PM   #3
Site Supporter
Site Supporter

Join Date: Mar 2007
Location: Toronto (for now)
Posts: 1,748
a) welcome to DSLR's, larger sensor = less DOF ... that ain't gonna change.

b) Who the hell buys a Pentax for continuous AF, it's the one area Pentax is still miles behind in.

c) You should be using manual focus anyway

d) You should be using a shutter speed of about 1/60th anyway if you're panning

e) The light is the light, iso50 and 1/1000th is iso 100 and 1/500th
10-23-2009, 07:32 PM   #4
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 13,799
I was thinking his numbers don't add up, but what do I know?
I'd suggest practicing a bit more before you blame the equipment. It sounds like you are having trouble with basic settings, this won't change no matter what brand you buy.
BTW, in bright sunlight, you should be getting ~ f6.3 @ 1/1000 second with ISO 100.

10-23-2009, 08:29 PM   #5
Veteran Member

Join Date: Sep 2009
Location: Texas
Photos: Gallery
Posts: 3,499
Original Poster

Last edited by r0ckstarr; 11-11-2011 at 11:07 AM.
10-23-2009, 08:55 PM   #6
Loyal Site Supporter
Loyal Site Supporter
Canada_Rockies's Avatar

Join Date: Nov 2007
Location: Sparwood, BC, Canada
Photos: Gallery | Albums
Posts: 12,230
QuoteOriginally posted by r0ckstarr Quote
With 100mm I wasn't even coming close to that.
Sunny 16 rules. Doesn't matter what camera you are using, these are the numbers that work.

At ISO 100, bright sun behind you:
1/100 @ f/16
1/200 @ f/11
1/400 @ f/8
1/800 @ f/5.6
1/1600 @ f/4

I used those (and the other variations - look up the Sunny 16 rules) for 20 years before I got a metered camera. I found it much quicker than anything else out there, and still use it with the M lenses, and also at times with the rest.
10-23-2009, 08:59 PM   #7
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,948
It's easy to be frustrated when an expensive purchase doesn't give the results you were hoping for. Here's something to consider:

Are you looking at the K-7's images zoomed to a 1:1 pixel view, or are you downsizing them for screen (or printing them)? I'm looking at dpreview's samples (and numbers) for your previous Samsung 815 Pro and for the K-7, and it looks to me that the K-7's ISO 400 is easily as good as the Samsung's ISO 100 and that's without considering the increased resolution. If you sacrifice some detail by applying noise reduction, you should be able to get images from the K-7 at ISO 1600 that compare favorably to the Samsung's ISO 100 when viewed or printed similarly.

That said, with such a tiny sensor, you get a very large depth of field. When the lens on your old camera was zoomed out all the way and wide open at f/2.2, everything from about 5ft to infinity is in focus. No wonder the focus speed of that camera (often listed as a major "con" in the reviews I'm skimming) didn't seem like an issue: it wasn't.

To get a similar effect with the K-7, you'd want to stop down to f/5.6 or so less than 3 stops more than f/2.2, so you could get the same shutter speeds with the K-7 at ISO 320 as at ISO 50 with your old camera, and the same high depth of field.

But of course, you don't really need (or necessarily want) all of that depth of field. Having a large-sensor dSLR gives you the flexibility to stop down like that if you want or you can use a faster aperture and anticipate where you want to focus before the action gets there.

On the other end of the zoom range, it's not so pretty (for either camera), but if you focus at about 100 ft out at full zoom on the Samsung 815 and wide open at f/4.6, you get about 20' of in-focus depth. With the K-7 at the same equivalent focal length (280mm on the lens), you'll get similar DOF from f/13 -- again, about three stops.

Last edited by mattdm; 10-23-2009 at 09:12 PM.
10-23-2009, 09:20 PM   #8
Damn Brit

QuoteOriginally posted by r0ckstarr Quote
I always shoot in Manual Mode. Always have. I don't like the camera automatically choosing the best shutter speed, or ISO for me.
So why are you using AF?
10-23-2009, 09:30 PM   #9
Veteran Member

Join Date: Mar 2009
Location: Perth Australia
Photos: Albums
Posts: 1,514
are you shooting with a tripod? and if so have you turned off shake reduction?

are you doing panning shots? and if so have you turned off shake reduction.

Those are two areas where shake reduction will work against you.
10-23-2009, 09:46 PM   #10
Veteran Member
Pentaxor's Avatar

Join Date: May 2009
Location: Vancouver, B.C.
Photos: Gallery
Posts: 6,513
QuoteOriginally posted by r0ckstarr Quote
I guess it's because it's different than what I am used to, that's all. I wasn't really blaming the camera except for the sharpness and grain issue. Also the slow lens and lack of faster lenses.
RockStarr, I don't want to be mean, but before you blame anything else, whether if it's sharpness and grain issue, or slow lens and lack of faster lenses, please work on your photography skills first.

I suggest you take note of the misconceptions that you have regarding cameras.

cardinal rule, if your exposure is all mixed-up , it will affect your images sharpness and noise. it doesn't matter if you have a faster lens or not.

P&S and dSLR's are not the same. they behave differently because of sensor size.

lastly, dSLRs are not your casual point and shoot user-friendly camera. it requires skill and knowledge to produce outstanding motosports photos. the camera doesn't do that automatically for you.

p.s. for someone who always uses manual exposure mode, I find it odd why you can't shoot way above 1/250. why is that? are you sure that you are really shooting under manual exposure mode? btw, it doesn't matter if you had used a P&S cam or a dSLR. both cameras' shutterspeeds can be adjusted if you really know or really use manual exposure.
10-23-2009, 09:47 PM   #11
Veteran Member
Pentaxor's Avatar

Join Date: May 2009
Location: Vancouver, B.C.
Photos: Gallery
Posts: 6,513
QuoteOriginally posted by Damn Brit Quote
So why are you using AF?
probably he meant Manual exposure mode, not manual focus. as he was asking, how can we boost up shutterspeed?
10-23-2009, 10:29 PM   #12
johnmflores's Avatar

Join Date: Apr 2009
Location: Somerville, NJ
Photos: Gallery | Albums
Posts: 5,355
Hey Brian,

I took a look at one of your photos on Flickr:
on Flickr - Photo Sharing!

And here's the exposure data:

Exposure: 0.5
Aperture: f/5.6
Focal Length: 110 mm
ISO Speed: 200
Exposure Bias: 0 EV

First of all, it's surprisingly sharp for a half-second pan photo. Well done to you and also a little to the K7's shake reduction.

Any lack of sharpness in this shot is likely to do with the shutter speed more than anything else. Even this one - Flickr: More detail about - is surprisingly sharp considering the fact that you are shooting 85mm @ 1/6.

In case you didn't know, the general rule of thumb is that 1/Focal Length is the slowest shutter speed you can hand hold before you start getting blurriness or need a tripod. Shake Reduction can usually help you a stop or two. Coffee usually costs me a stop ;-)

If I were in your situation, I'd balance ISO and Aperture to get the shutter speed closer to 1/Focal Length or 1 stop slower. If it's a choice between sharpening a blurry photo or reducing noise, I'll take the noise reduction every day. It's easy to do with the right tools.

If you are shooting fast moving cars, consider your position. Coming right at your @ 100mph is much more challenging for the AF than catching them as they drive across the frame. If you are panning, the AF should be up to the task. If they are coming at you, consider using MF or catch-in-focus.

Finally, the focus issue. If you are having problems, don't let the camera pick the focus point. Pick it yourself and work accordingly.

Don't despair, there are people here doing quite alright with older Pentaxes, shooting cars and motorcycles and other moving objects. Give it some time to learn the camera. It's tougher to master than a point and shoot but so much more satisfying when you do.
10-23-2009, 11:01 PM   #13
Veteran Member
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
I'd suggest posting specific pictures - with EXIF intact, or at least with pointers to the image page in Flickr so we can see it there - from boht the K-7 and your old P&S, to demonstrate what you are talking about. Because as people have mentioned it, on the face of it, things don't really add up. Although to some extent, the things you are describing are just hard.

With the Samsung, I could run 1/1000 shutter speeds in sunlight with f/2 and ISO-50 and be perfectly fine...
With the K7, I barely get 1/250 at 100 ISO and f/3.5
Lighting that yields 1/1000, f/2, and ISO 50 should also yield 1/1000 at f/2.8 and ISO 100, or 1/750" at f/3.5 and ISO 100. If you're only getting 1/250", then you must be dealing with less light then you had before. Not all sunny days are equally bright. Also, if you're using any kind of filter on the DSLR lens, that could be reducing light levels some.

With the aperture wide open, I get a shallow depth of field.
Yes, that's how exposure works. Smaller sensor P&S cameras don't ever get *as* shallow a DOF, but all APS-C cameras will yield the same shallow DOF at a given focal length and aperture.

The camera likes to auto-focus on the nearest thing in the frame. Really annoying when you're trying to follow a car around a corner with continuous AF.
Have you chosen the focus point, or are you letting the camera do it?

If I turn up the ISO, the IQ suffers.
Maybe a tiny bit if you pixel peep and don't run any NR, but if you want fast shutter speeds at small aperture, you've got no choice but to raise ISO. And really, you should be able to get full-page-magazine-publishing-results up to, say, ISO 800.

im still getting horrible pics because of the slow lens
Obviously, then, a faster lens would help - so why blame the camera?

All of my pics look like they were shot with 100 speed film. They have what looks like film grain to them. This wasn't a problem with my previous Samsung. Everything was nice and clear.
Sure, if you shoot lower ISO, you get less noise. But at the same ISO levels, the K-7 should be wiping up the floor with any P&S. If not, that suggests the P&S might have been applying extremely heavy-handed, detail-killing NR. So do the same with the K-7 if you prefer that look. You might want to post some pictures to demonstrate what you are talking about here too.

If I cannot get quality images from this camera, I may be switching to a different brand that offers faster lenses and better ISO performance. I purchased a lens with f2.8. I hope that will help with a faster shutter speed when it arrives.
Well, of course f/2.8 is half a stop better than f/3.5. Not sure what focal lengths you are talking about, but Pentax *does* offer faster lenses at soem focal lengths. As has been pointed out several times so far, though, your numbers aren't adding up. There must be a difference in light levels explaining some of the difference in exposure.
10-23-2009, 11:43 PM   #14
Senior Member
chedoy's Avatar

Join Date: Dec 2006
Location: Chicago, IL
Posts: 143
I looked at your 24 hours of Lemons series. Always wanted to go see that. Must have been a riot. I would think you could go higher on ISO. The K-7 should be able to do 800 easily with minimal grain and let you get the shutter speeds back over 1/500 instead of the 1/80 you were using.

Did you perhaps have a polarizer on the end of the lens?

P.S. Your book on Hurricane Ike looks like it has some good shots.
10-23-2009, 11:57 PM   #15
Veteran Member

Join Date: Sep 2009
Location: Texas
Photos: Gallery
Posts: 3,499
Original Poster

Last edited by r0ckstarr; 11-11-2011 at 11:07 AM.

  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, pentax help, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
Machinery Motorsports with the DA* 50-135mm Gaelen Post Your Photos! 19 10-21-2010 08:51 AM
Got me a Hanimar lens I am liking! metroeloise Post Your Photos! 8 05-07-2009 09:20 PM
For My Next Trick: Motorsports Mike Cash Photographic Technique 3 02-14-2009 05:31 PM
I'm liking this 40/2.8 kb244 Pentax SLR Lens Discussion 1 12-12-2007 11:57 PM
Anyone else shoot motorsports? GirlsGoneRacin Pentax DSLR Discussion 11 02-02-2007 02:11 PM

All times are GMT -7. The time now is 02:20 AM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]