I just wanted to point out something here - there is nothing unique about Lightroom in respect of its edits being non-destructive. This is simply the case because it acts (when using RAW files) as a 'Raw Converter', as opposed to a image editor (which Photoshop is). All RAW converter programs work 'non-destructively', that is the nature of the beast. The changes made to the sliders are just recorded as settings data, and applied through processing when requested by the user (such as ticking a preview box).

You can happily and non-destructively change settings back and forwards in any order in a RAW converter, and it will not affect the final output at all. You only commit to that output when 'Saving As' - to a Tiff or Jpeg. Most converters will store the settings you made as metadata, either written into the RAW file itself, or as seperate 'Side Car' files that will open when you reopen the RAW again, and return all the sliders to the same settings.

One of the questions from the Original Poster was about whether some settings would affect the RAW file. We've had a thread about this a while back when I first joined when I asked about applying chromatic abberation corrections in camera.

What I learned from all that and further experimenting, is that (as mentioned just above) settings that would be applied as 'processing parameters' to a JPEG will not affect the basic look or quality of the RAW file. This applies to settings such as : Noise reduction, Chromatic Abberation, Distortion Correction, Custom Image settings such as Saturation, Hue, Lanscape, Vibrant, sharpness etc etc. They would be applied to any outputted JPEG.

Be aware though, that even if not outputting JPEGs, having some of these settings activated will slow down the camera shooting speed - the processor carries out the calculations and stores the data in the RAW file.

This brings up the second point - all of these settings will be recorded in the RAW file. If this file is then opened in a program that can read and apply all of these settings, then you will see their affects on the preview when you open up the file. The only program I am aware of that can read and interpret all of these settings is Pentax Digital Camera Utility.

If the file is opened in another program, (eg Lightroom, Sagelight etc), you would not see the affect of many of these settings, just the standard preview of the base image.

I am looking for any thoughts or advice, regarding the use of system backup programs for photos.

It seems that all the popular backup programs, eg acronis, O & O etc, all use compression techniques for their backup data. This makes sense in general, because the space needed on external drives is reduced. For full system backups this is a good idea it seems.

But I was concerned about allowing this compression to occur with my photos, both original DNGs and TIFFs & JPEGs also. In the back of my mind was the worry, if I lost my laptop or the drive failed, I'd have to restore from the backup, and would the de-compressed photo files have suffered in any way after being restored?

In the end, I have created entirely separate full copies of my photo folders, both on DL DVDs and USB drives, with no compression, just full copies, as I felt worried about this. Is this a good idea, or is it OK to just let the backup software do its thing and expect the photos will be just the same when restored?

In defence of the lowly K7's capabilities, here are a couple of shots I took recently - iso 1600, no flash, lens was an 'A' 28mm f2.8. I did remove some shadow noise, but the edge detail was easily bought back.

I was getting workable shutter speeds in the region of 60th-90th sec, and I feel the quality was great.

As I understand it (I've always assumed), if you stuck a DA APS-C lens on a FF camera, then you'd have black space around the edges, because the image projected is a smaller circle than the sensor is recording. Pentax may be the only brand that this could be tested on I think, because the other brands have different mounts for the two types (Eg Canon Ef / EF-S).

Sorry, that last sentence should be ' a uniform feel' !

Dave, if at all possible try and get an original new Pentax grip - I am sure it will be worth it, and complement the K5 beautifully. I looked at the various copies available before getting my BG-4, and there were plenty of little moans about them on the various review sites.

I paid £179 (I think it was from fotosense), well worth it. As well as the weather sealing it also has nice little touches like a groove to put the little plastic & rubber caps that come off the bottom of the camera protecting the connectors. The controls also are exactly the same as the equivalents on the camera, keeping a unfifrom fels when switching quickly from landscape to portrait and back.

I agree that more DOF would have been ideal here, if possible with the lighting available. Maybe you could have got away with a stop or more on the ISO David?

But I am impressed with the quality and depth of the colours. I posted a few days ago on some other butterfly shots, suggesting that a half stop or so less exposure would have given more saturation, and this is exactly the kind of result I was thinking of. Did you dial in any minus exposure compensation?

I've checked my BG-4 grip and I think you could get the film cartridge into one of the slots on that.

With a ball head you can instantly adjust the camera on every plane in one go - for my uses, mainly landscapes or portraits, I think this will help me get set up ready to shoot more efficiently. For studio and more controlled situations the finer adjustments on individual planes offered by a lever type head is more ideal I guess.

As for finer control, well lets see. I think John, you're right, what we see as a natural horizon is not always actually a perfectly level line with the earths surface. I'm thinking this is what the auto horizon correction will be detecting, and may explain the problems David referred to?