Using 200mm lens query

i am using a 28-200 mm lens when at full zoom is it nesesery to us a tripod as all my shots look terrible even with the anti shake on,thanks for any feedback

There's a rule of thumb that says your shutter speed should be 1/focal length to avoid shake. So for a 50mm lens you want a shutter speed of 1/50 or faster, for a 100mm lens it'll be 1/100 or faster, for a 200mm lens 1/200 or faster, etc.

A 200mm lens can usually be hand held in bright daylight but when the lights go low (or you're indoors) then you'll need to increase the ISO or open up the aperture to bring the shutter speed back up - or, use a tripod.

Looking at the other post , you will have a max aperture of 5.6 at 200mm. That is slow and in darker conditions you will need to use a slow shuter speed to get a correct exposure. Even with S/R you are going to get camera shake at 1/60th second and below.

What shutter speeds are you shooting at ?

assuming the lens is auto focus things to check
1/ is the camera set to AF.S
2/ is the prog. dial set to what you want Eg."green"
3/ what is the metering mode set to
4/ Try setting the Focus mode to centre
5/ is the flash symbol "blinking" in the viewfinder

A tripod will always help, but isn't necessary for 200mm @ f5.6 in average daylight if you're prepared to use medium to high sensitivity (ISO settings).

You need to understand aperture, shutter speed and sensitivity, and how they relate to each other. Any good general book on photography will help with that. It doesn't have to be written specifically for Pentax cameras, or even digital cameras.

Also remember to factor in the 1.5 crop which makes the 200mm lens a 300mm lens and therefore you would need a shutter speed of 1/300 sec or faster. This is what I do and results seem fine so far (subject matter is another thing entirely )
It starts to get complicated when you are a noob but is well worth sticking at it.
Harry

Is this really true? I believe a 200mm lens is 200mm no matter what sensor size you have. So the 1/focal length rule should still apply.

However, thinking as you do, Harry, will at least keep you on the safe side .

This is how I came up with the 1/60 minimum with S/R. Assuming 2 stops of gain with the S/R from 300mm.

The 200mm lens does not actually become a 300mm lens, but for handholding purposes you you treat it as such.

It is still a 200mm lens, but the crop sensor image needs more magnification/enlargement than a 35mm neg or full frame sensor, and thus any camera shake would be more noticeable.

Yes, and it's even in the instruction book. It is still a 200mm lens, but as stated already it has the field of view of a 300mm on 35mm, so 1/300 sec would be the minimum for reasonably sharp images.

Frankly I can't hold such a lens that steady though - it wavers all over the place - so I would go for as fast as possible, plus SR where available! Of course a sturdy tripod would be better....

The 300mm lens does not exist! Why stop at the equivalent on a 35mm camera? It might be a 2000mm equivalent on a 10x8 camera So use 1/2000th sec. in that case

shim

Actually it works the other way round, but always for a given magnification, not for a given focal length.

A standard lens on a Minox sub-miniature is a 15mm, but has the field of view of a standard lens, but because of the huge magnification needed is more in need of a tripod than a standard lens on your 10"x8" view camera. If you were making 10"x8" prints from both, in the case of the larger format it would be a contact print, in the case of the smaller one it would be an enormous enlargement.

Now don't get me started on depth of field again!

because at 35mm film size the rule of thumb works nicely for most people.

Technique plays a role here as well, here are some tips for whatever they may be worth, they work for me. I'm not the worlds best photographer, but I am disapointed if I get noticable camera shake at 1/60th and 300mm (450 equiv) with SR on.

0. Establish a stable base, Seems obvious, but if you aren't stable neither is your camera. Get a good footing with feet shoulder width apart. BTW this is zero because I thought of it half way through and didn't want to re-number everything.

1. Relax, don't grip the camera too tight since tense muscles tend to shake more

2. Breathe, take one or two deep breaths, then stop comfortably before you release the shot. By comfortably I mean simply stop breathing at a comfortable point in your breath cycle, not conciously holding your lungs full or empty. For me this is ~1/2 way.

3. Brace yourself, this can mean leaning on a convinient wall, or just tucking your elbows in against your chest will help some. Triangles are the key here.

4. Slouch, you'll look stupid and your mum will shout at you for bad posture, but you'll shake less. Same reason as 1. I usually go into a slouchy posture as I breath out before I release the shutter

5. Having framed your subject, gently gently depress the shutter. It should take you slightly by surprise when it goes off.

6. Follow Through, when the mirror blackout finishes and the viewfinder image returns, you should still be looking at your subject, beautifully framed. With practice you will have a pretty good idea at this point weather or not the shot came off.

7. Multiple exposures, as a last ditch, when the best shutter speed I can get is really too slow (say under 1/60th at 300mm), I start shooting in bursts of 3 frames. The middle one will often be the best of the three, since you didn't move to take it.


Obviously for fast action some of these become more difficult, but I reckon good technique is worth at least 2 stops.

Mongoose,

How long did you work as a sniper for special forces ?

Thanks Mongoose..... good tips...... my problem is that I always sneeze at the exact moment I press the shutter!

shim