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johnriley

Joined: 19th March 2002

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johnriley
Flash. The flash will be the dominant light source.

Having said that, I usually use AWB for flash.

Comment by johnriley posted on White Balance settings at 10/11/2007 - 21:56

johnriley
So far I've not found an LCD screen that I really like. We are about to look at flat screen TVs, but want to avoid the horrible excessive contrast that many exhibit.

Any tips for new and really good monitors and TV sets?

Comment by johnriley posted on whats the deal with the Shake reduction at 29/12/2007 - 17:40

johnriley
Quote:
Does anyone know what the downside is if you forget to turn off shake reduction?
I leave it on all the time unless the camera is on a tripod.

The only downside I can think of is perhaps a minute increase in battery useage.

Comment by johnriley posted on whats the deal with the Shake reduction at 11/11/2007 - 10:19

johnriley
OK, in addition to what I've just posted in another reply regarding DOF.

Shake reduction means perhaps 1-4 stops axtra speeds with sharp results, depending on the individual. An example could be a 50mm lens, which gives a 35mm-equivalent of 75mm.

This would normally mean that 1/75 sec was needed for a reasonable chance of getting a sharp image, call it 1/60 sec if we are steady handed. The SR feature means I might expect a sharp result at 1/15 sec for sure and I'd have a go at 1/8 sec anyway.

With a 300mm lens (450mm-equivalent) needing 1/450 sec, call it 1/500 sec, I'd probably be OK at 1/125 sec and would certainly try down to 1/30 sec in extremis.

Of course "sharp" is relative and also depends on how big the final enlargement is going to be. A 6"x4" print is less demanding than a 20"x16" one.

For ultimate sharpness, turn off SR and use a very solid tripod. With SR very long exposures will be an unrealistic expectation.

Comment by johnriley posted on whats the deal with the Shake reduction at 10/11/2007 - 14:44

johnriley
I think we were.

Comment by johnriley posted on aperture settings for detailed foreground and background at 10/11/2007 - 16:09

johnriley
There is no escaping that small apertures such as f11 or f16 need longer shutter speeds. The two are inter-related.

However, there are three additional options. The most effective is to use a tripod and eliminate the camera shake that way. No good for moving subjects though - even moving grass and trees on a windy day. However, perfect for still subjects.

You can also increase the ISO value on a digital camera, which will result in higher noise (grain) but will mean less shake. Better to have a sharp grainy picture than a blurred fine grain one.

Finally you can use Shake Reduction technology. This works very well with the Pentax DSLRs and enables much sharper pictures at speeds lower than was previously thought possible.

The final factor is the point of focus. If you want maximum depth of field (sharpness from front to back) then you focus on the hyperfocal distance. Without going into the technicalities of this, which could simply confuse the issue, what you do is follow a rule of thumb. Set a small aperture (say f11, f16) and focus on a point one third of the way in.

So, if you wanted everything in focus from say infinity to maybe around 10 feet away then you might focus on a point around 15-20 feet away.

Just approximate one third in and don't worry too much. It should be close enough.

Some older lenses have depth of field markings on them, but modern zooms don't.

Hope that helps!

Comment by johnriley posted on aperture settings for detailed foreground and background at 10/11/2007 - 14:36

johnriley
With a DSLR I think having just a 50mm would be a bit restrictive.

If you want better quality than the 18-55mm and yet want to keep the versatility of a zoom then the 16-45mm will not disappoint.

Comment by johnriley posted on how much better would a 50mm prime really be? at 27/11/2007 - 23:08

johnriley
Using a 50mm lens on a DSLR is equivalent to using a 75mm lens on 35mm, which makes it a fair enough portrait lens. Personally I would prefer something slightly longer, but that's quibbling!

A lens can be in focus but give a soft effect because of residual abberations and lower resolution. This is sometimes very advantageous for flattering portraiture.

If a lens behaves this way when at and near open aperture, then backgrounds can be noicely out of focus as well. Such lenses often become very sharp when stopped down, so are suitable for a wide variety of subjects.

Comment by johnriley posted on how much better would a 50mm prime really be? at 13/11/2007 - 15:56

johnriley
That's a tough one to answer, ChrisA. Maybe there is no easy answer.

However, probably you can be relatively sure now of the various qualities of many pentax, Tamron and Sigma lenses in particular that have been extensively discussed here.

I don't know if you are aware of www.photodo.com which is a sister site to this one and all about lenses. There are extensive tests there and also owner reviews as well.

See you there?

Comment by johnriley posted on how much better would a 50mm prime really be? at 11/11/2007 - 22:45

johnriley
Why not just try it and see what happens?

The flash compensation should reduce the output of the flash which would stop your foreground being over-exposed. You could also move your subject slightly further away.

Comment by johnriley posted on K100D flash compensato at 10/11/2007 - 14:52

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