In response to some other threads, I thought it appropriate to give a little guidance on the way you should set up a Windows machine for colour with Capture One and Photoshop.

First of all, you need to decide on a colour space you are going to work with (as a rule). I suggest one of three:

• AdobeRGB: my preferred everyday choice. This can handle a good range of colours and is ideally suited for printing - both offset litho and modern inkjets (which have driver options for AdobeRGB)

• ProPhoto: an astonishingly wide colour gamut. This can cover almost any colour you can see. However, because it is so wide you should always work in 16-bit per pixel mode, otherwise you risk posterisation. If you want to eek out every ounce of colour detail, or have absolutely precise adjustments in colour, then this is a great colour space.

• sRGB: if you don't want to get bogged down in colour stuff, then sRGB is the choice for you! It's the gamut that the web uses, as well as most high-street and internet printing services. It's pretty cramped colour wise, but generally it will do fine (but this one is last on my list when it comes to editing images!).

Calibrate your monitor
An absolutely essential step! Preferably you should use something like a Spyder/Huey etc which will physically measure your screen and produce a profile. Failing that there's the free WiziWYG from www.praxisoft.com - which is available for both Mac and PC (95,98,XP).

If you use WiziWYG, pick "Generic LCD" if you have an LCD monitor, and use D50 white point (but have very subdued lighting in the room), and 2.2 gamma.

Once your monitor is calibrated Windows will always display through that profile - you never need to reference the monitor profile again (it is used by the video driver, and once setup should always use it).

Setting up Capture One
Go into the colour management settings and set "Output destination (working space)" to your chosen colour space.
e.g. AdobeRGB

Never should this be your monitor profile or anything else. Capture One will translate the CCD information, using the "Camera Profile" you choose (e.g. Pentax istD generic v2) into that working space. This working space should be a standard - i.e. one of the three I listed above.

It's worth noting that you can try other "Camera Profiles" for your Pentax DSLR. Try any of the Nikon D100 profiles as they share the same sensor Capture One provides a "Portrait" profile that has much more muted colours. By changing the camera profile C1 is assuming the DSLR has a slightly different response - but still it will convert into the "Working space" - which should be AdobeRGB (or one of the others).

Setting up Photoshop
Go into the "Color Settings" dialog and, under "Working Spaces", set RGB to your chosen colour space.
e.g. AdobeRGB.

The "Conversion Options" can be set as follows:
Engine = Adobe (ACE)
Intent = Relative Colormetric
Use black point compression = checked
Use dither (8-bit/channel images) = checked

Under CS and CS2 there are "Soft Proof" options. For 99% of photographic work you should completely ignore this and not enable the Soft Proof! I'll can explain, but it's another huge chunk of info...

Saving for Web
If you are not using sRGB as your chosen colour space, then before you save for web you need to convert into the sRGB colour space.
Photoshop provides the option to do this under the Image menu (and annoyingly CS/CS2 puts it in a different place compared to PS7 and before).


I'll update this post with some more details later, but hopefully this should clear away some misunderstandings of colour!

Graham,

As I mentioned, all the genuine Pentax SMC-A, SMC-F, SMC-FA and newer SMC-DA will all work perfectly well on the *ist-D series.

Regarding 100mm vs 50mm - it depends on your needs! I find 100mm is just perfect for flowers, longer distance portraits, and the like. You see I do also have a non-macro 50mm/f1.4 which complements it nicely.

You are right, I have the (very) old SMC-F 100mm/f2.8. After the SMC-F came a redesigned body shape with a larger focus ring. Optics generally remained the same - these were the SMC-FA series. The new "D" 100mm/f2.8 is probably closely related to the older 100mm's, but is smaller, lighter, and does require a hood (which is supplied).

The point is - you can often find the older 100mm macros on ebay, and at second hand camera shops (I got mine from LCE Group for £200). I did ponder "upgrading" to the newer lens, but it's such a good lens already and I like the weight

The Tamron 90mm macro is well regarded... but I made a conscious decision to stick to Pentax only glass - it means I have consistency of colour, contrast, bokeh, and controls (like zooms all work the same way). I would rather go for a good condition second hand Pentax than a new other make... but that's only my decision As I said, many have been very happy with the Tamron.

Places to check for 2nd hand: www.ffordes.co.uk (can be expensive), www.mxv.co.uk, www.lcegroup.co.uk

Hope that helps!
Matt

Graham,
First off - if you have extension tubes, then any of the old K-mount 50mm f/1.7 lenses would work very well and should be a lot sharper than any zoom. Something like the SMC-A 50mm/f1.7, or SMC-F 50mm/f1.7 or SMC-FA 50mm/f1.7.
The F and FA are autofocus, while the A is manual focus. All three work great on the *ist-D.

If you want a dedicated macro lens, then these are some points to bear in mind:
* The SMC-F and SMC-FA 100mm/f2.8 lenses are superb. But heavy Built in lens hood. Astonishingly sharp, and superb for portraiture too (though sometimes it shows just too many skin blemishes!!). Will work fine on extension tubes as well for super close work.

* The new macro lenses (both 50mm and 100mm) don't have aperture rings. This is a problem for extension tubes, unless you have tubes which have electrical contacts.

If you want super, super close, then a 50mm/f1.7 prime reverse mounted will be astounding

Expect to pay around £200 for an SMC-F 100mm/f2.8. The 50mm/f1.7 prime in autofocus is around £70, while in manual should be around £30? (saw one go for £9.50 on ebay!)

You really do need to know a little more about your anticipated subject first. The longer macro lenses (like the 180mm) will be much easier for insects. A 50mm macro will be very difficult for insects - you have to get too close and they zip off!

Personally I love the SMC-F 100mm/f2.8, tho' it is a big brute. Works a dream on both my *ist-D and *ist-DS.

Generally any K-mount lens will work just fine on the *ist-D. Best to stick to the SMC-A (man focus), SMC-F (autofocus), SMC-FA (autofocus) and SMC-DA (new digital) series (the older SMC-M are manual everything and are a bit of a pain but will work).
That's the great thing about Pentax - superb backward compatibility!! If you are aiming for non-Pentax, then make sure the lens has an "A" setting on the aperture ring and you should be fine... though I'd strongly recommend trying to find Pentax SMC lenses

Hope that helps!
Matt

Philip,
As far as I'm aware it's just down to the aperture used. I can get loads of dust spots and specks when using f/22 on landscapes.

The worst is when using a pin hole! This showed up just how filthy my CCD was

However, it does also depend on having a smooth area to notice the dust spot. Skies are a good one. But macros are more susceptible in that you are much more likely to have smooth areas because of the extremely shallow DoF.

When you think about it there is absolutely no difference between the light hitting the sensor from a wide angle lens and that from a macro. And ideally for CCDs the light should hit the sensor at right angles.

Regarding cleaning - apart from the rocket blower, I've used the "homebrew" approach many times using PecPads and a drop of Eclipse cleaning fluid. This was good, but I've recently had the DSLRClean recommended (from http://www.intemos.com/ ) and found them extremely good. After nearly three years of solid use (and >14000 shots) the CCD still needed a reallly good clean. I went through 2 sticks using their cleaning solution, and 2 dry sticks. Now I'm pretty much dust free, save for extremely small stuff.

The surface of the CCD is tough - you just have to be careful not to drag dust across it. One of the worst things that can happen is the batteries fail while you're cleaning - because then the shutter gets damaged. (But the *ist-D starts bleeping furiously at you just before the batteries completely go!)

Matt

Phil,
Sounds strange. But maybe that's just Sigma.
I have used the SMC-F100 with full auto extension tubes too
http://www.ephotozine.com/gallery/showlargepic.cfm?photoid=261457
I did also try with the 1.7xAF converter too - but you're getting into microscope country then!
Matt

No
You're probably holding the camera already - so it'll be at the same potential anyway

I'm not saying anymore...
Matt

The problem with high levels of static and sensitive components is that a discharge may puncture a small hole in the substrate of the semiconductor. Worse still, it may just weaken the substrate so that it fails later on

If you've ever visited an electronics fabrication plant you'll know they have very strict static precautions (foot wear, wrist bands, etc). Yes, it's less of a problem once the kit is built, but you should still be cautious about the possibility of discharges!

Matt

Maybe... maybe not.
It may clean the dust, BUT, one thing a vacuum cleaner can produce is huge amounts of static electricity. Shifting all that air produces friction and can result in high static discharges.
Since all digital cameras contain electronic components (and very high density and sensitive ones), personally I would try anything other than a vacuum cleaner
(And yes, I know what I'm talking about - I've been in the electronics inducstry for many years)

Just my 2pence worth

Matt

Dust does get in.
Generally it doesn't affect the images, but if you try this you'll find out just how much dust you have (or haven't):

* Point the camera to a cloudless piece of sky (if you can find some )
* Put to manual focus and set to a close focus point
* Set the camera to f/22 (or smaller)
* Use the lowest ISO setting

If you've got dust you'll see little grey spots on the image.

The absolute best thing to use is a pin-hole (rather than a lens). That way the huge f-number really makes the dust visible. But that's being picky

Most large gunk can be blown off. No problem.
Smaller bits are easily cleaned with the above mentioned methods. There's no need to be paranoid about it - just careful (like you are when cleaning your most expensive lens).

And even when you've cleaned, the little bits get back again. It's a balance between how much you care about the spots, how much time you have to clone and heal in PS, and how many times you want to clean the CCD.

But either way it's no big deal
Matt

Peter,
If you want to try out a cleaning fluid - try it on a "Pro" filter. They're pretty tough and will show up any streaking problems (or the like).
Matt