Wait til the weather warms up a bit Stan.... BRRR!!!

The Jessop or Teleplus 1.7x's have all the contacts and work
well with the Sigma 150-500mm, which is the only Sigma lens
I have. It also works brilliantly with the Pentax 55-300mm.

I also have the rare Tamron 1.4x which doesn't give very good images
with the Pentax 55-300mm but works with the DA*300mm f/4 and probably
the Sigma 150-500mm.

See this thread.

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Bugger! the ICE is melting in my rum and coke
I'll have to go and sit outside!

All flights have been cancelled to and from
Wigan George Formby Airport due to the
snow and the Paddle Steamer service has
also been called off due to ice stopping them
docking at Wigan Pier

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I doubt if this will work properly with a tele-lens.

I've never met anyone who knows how to work it even with
a 50mm lens

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I did mention ISO 160 about 6 posts back
It seems that the Highlight protection underexposes by 1 stop
which isn't a bad idea anyway, you can easily lift it in PP and
if you do burn out the highlights they can't be recovered.

After a bit more research it does seem that the Highlight/Shadow
protection is applied to the in camera JPG's and that the
Pentax computer software can apply it to the RAW files.

As long as you underexpose any bright highlights shadow detail
can be recovered from RAW's in PP without shadow or highlight
protection. It's hardly worth bothering too much about dynamic
range because a monitor only shows about 8.5 stops anyway. Any
extra noise in the shadows at 200ISO won't be very visible.

This is a good but boring 3 video demonstration...

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The K-5 Manual doesn't explain this in detail. I'll have
to have a look around tomorrow to see why they restrict
the minimum speed to ISO 160-200 and if it applies to
JPG and RAW. If it's not needed in RAW why is it there?

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Are you sure about that? They definitely wouldn't be any
use for JPG's

The Nuthatch in my portfolio was rescued from a black DNG
file. I've still got the JPG as well I might see how much
I can rescue from that.

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I can't think of any downsides as long as the exposure is
correct. You would of course need good light and it would
work well with flash.

It does effect the highlight/shadow protection, but I think
you are restricted to ISO 200 with that anyway.

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Select the "Measurements" TAB

It's a TAB that says "Measurements"

Not the TAB that says "Specs"

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