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12-30-2011, 06:41 PM   #1
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What is FF?

Reading up on the Kr and there is a lot of talk about FF problems. What is this and how does it affect the picture?

12-30-2011, 06:42 PM   #2
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front focus. the picture would be out of focus, or the focus would be slightly off if this was happening.

FF can also mean full frame.
BF is back focus.
AF is auto focus.
12-30-2011, 07:51 PM   #3
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Front focus, or the autofocus has decided to focus in front of where you wanted it to. Many people have trouble with the K-r front-focusing in low incandescent-type light. Artificial light is rarely a broad spectrum like daylight; it has a color tint to it depending on how it's produced. Incandescent light is way towards the warm side of the scale, and the actual tungsten filament bulbs have a lot of output in the infrared region. The AF should take this into account because the focus point is different for different spectrums.

The focus point is more noticeable in low light because the lens is probably at or close to it's maximum aperture, therefore the depth of field is small. So you can see the point of focus better.

Autofocus is not perfect magic brain-reading technology so it can be confused in many ways besides incandescent light. If I had a K-r, I'd do some testing on my camera to see what it does and how I can adapt to using it.
12-30-2011, 08:12 PM   #4
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I thought FF was an excuse to have 600 posts on a thread ie Full Frame zeolites can't resist posting.

12-30-2011, 09:20 PM   #5
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QuoteOriginally posted by Bob from Aus Quote
I thought FF was an excuse to have 600 posts on a thread ie Full Frame zeolites can't resist posting.
Absolutely! Maybe more.
12-30-2011, 09:50 PM   #6
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FF:

front focus
full frame
Furry Freaks
Flying F*ckheads (I once worked for FFI)
(255 in hexadecimal)
Fantastic Four
Fan Fiction
Foo Fighters
Final Fantasy
fast forward
(large bra size)
femtofarad
formfeed

and a few others.
12-31-2011, 06:18 AM   #7
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QuoteOriginally posted by Bob from Aus Quote
I thought FF was an excuse to have 600 posts on a thread ie Full Frame zeolites can't resist posting.
Actually I thought it w 256 in hex code, or is that the number of posts you get when you start a thread with FF in the title

To return to some of the other posts in the thread, incandescent light is actually broad spectrum, unlike fluorescent, or sodium light that are quite different. Sodium has 2 frequencies quite close together in the yellow band of the spectrum, and fluorescent has the mercury spectrum plus some frequencies of phosphorus depending on the coating, but neither are broad spectrum. Incandescent looks "warm" in color because it does not run hot enough to produce the blues in the spectrum that you have in daylight.
12-31-2011, 10:31 AM   #8
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QuoteOriginally posted by Lowell Goudge Quote
Actually I thought it w 256 in hex code
FF (hex)= 255
100 (hex)= 256

12-31-2011, 01:44 PM - 1 Like   #9
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I see Pichur has 9 posts. This thread is getting sillier and more side tracked by the post. Sorry Pichur we on this forum stay sensible most of the time but writing FF quickly opens a can of worms. Most future threads should be OK.
12-31-2011, 04:16 PM   #10
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QuoteOriginally posted by RioRico Quote
(255 in hexadecimal)
How embarrassed should I be that this actually made me laugh out loud?

As for the context of the OP's (original poster's) message, reading up on the Kr and FF, it equates to "front focus" or as another poster mentioned, the tendency of the Kr to focus slightly in front of where you'd expect it to under low level incandescent lighting. So in other words, if you're using the AutoFocus to focus on the eyes of a dog and when you look at the image, the eyes are soft but the tip of his nose is in focus instead. Under brighter light, the aperture tends to be a little smaller (higher number) and therefore the DOF (depth of field) is a little longer and both the eyes and the nose wind up in focus.

There are many suggested workarounds which if you've been reading up I'm sure you've found but IMHO (in my humble opinion) part of the true magic of owning a Pentax DSLR is the ability to own cheap MF (manual focus) lenses and therefore, YOU handle the focus duties for indoor low light portraits. If you are or will be relying on a Kr for [AUTO] mode indoor low light snapshots, again IMHO, you might want to switch to a point-n-shoot or a higher-end DSLR or a different entry-level with less features but better indoor tungsten AF or whatever.

I feel the need to add that I LOVE MY Kr! Even though I'm convinced it could be shown to exhibit the FF issue if properly tested, I have just never experienced it with the kind of shooting I use it for. I cannot imagine a better entry level DSLR for someone that is even mildly interested in learning how to leave the [AUTO] snapshot world behind.
12-31-2011, 04:51 PM   #11
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QuoteOriginally posted by RioRico Quote
Originally posted by Lowell Goudge Quote Actually I thought it w 256 in hex code

FF (hex)= 255 100 (hex)= 256
F=15 in computer terminology because computers start their count from 0...
Like this...0 1 2 3 4 5 6 7 8 9 a b c d e f (16 digits)
So if F=15........15*15=225.

F is equivalent to 16 in normal counting....So 16*16=256.

FF = 255 if you follow the hexadecimal count and start from 0
12-31-2011, 06:21 PM   #12
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There are indeed 256 values inclusive between 00h-FFh but those values are 0-255.

So
E->F->10 (hex) = 14->15->16 (dec)
and
FE->FF->100 (hex) = 254->255->256 (dec)

F does not equal 16 any more than 9 equals 10. Unless I cut off a thumb. Sorry.
12-31-2011, 10:08 PM   #13
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QuoteOriginally posted by RioRico Quote
There are indeed 256 values inclusive between 00h-FFh but those values are 0-255.

So
E->F->10 (hex) = 14->15->16 (dec)
and
FE->FF->100 (hex) = 254->255->256 (dec)

F does not equal 16 any more than 9 equals 10. Unless I cut off a thumb. Sorry.
Yes I agree with you.
It's just how you look at at.
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